Abstract

Obesity significantly impacts musculoskeletal health and alters walking biomechanics. This study aimed to quantify the influence of obesity on knee angle changes during various walking tasks and identify associated anthropometric predictors. We analyzed motion sensor data from 35 participants (12 normal-weight, 23 obese) performing six distinct walking tasks (e.g., preferred speed, obstacle negotiation). Knee angle difference (InitialPeak) was the primary outcome. Exploratory data analysis (EDA), including correlation analysis and Variance Inflation Factor (VIF) assessment, guided variable selection. Linear Mixed-Effects Models (LMM), Generalized Additive Mixed Models (GAMM), and Bayesian Mixed Models were developed, incorporating fixed effects for group, demographics, and selected body measurements, with random intercepts for participant and task. Model performance was compared using ANOVA and 5-fold cross-validation (RMSE, R²). Two-sample t-tests compared knee angle differences between groups for each task. EDA and t-tests revealed significantly reduced knee angle differences in the obese group across most tasks (p < 0.05), suggesting less knee flexion. The final LMM demonstrated the best fit and predictive performance (Avg CV RMSE \(\approx\) 2.59, Avg CV R² \(\approx\) 0.68), identifying significant associations between knee angle difference and Shoulder Breadth (positive), Chest Breadth (negative), Lower Thigh Circumference (negative), Shank Circumference (negative), and A Body Shape Index (ABSI, negative). Significant variability was attributed to both participant and task random effects. In conclusion, obesity is associated with reduced knee flexion during walking, and specific body dimensions beyond BMI contribute significantly to these biomechanical alterations.

Introduction

Obesity is a growing public health concern worldwide, with well-documented impacts on musculoskeletal health and mobility. Excess body weight alters biomechanical loading patterns during everyday activities, increasing the risk of joint degeneration and chronic musculoskeletal conditions. In particular, deviations in walking mechanics—such as reduced knee flexion and altered foot–ground contact—have been observed in individuals with obesity, suggesting a potential pathway by which obesity contributes to long-term joint dysfunction and osteoarthritis.

Knee angle during gait is a critical marker of walking stance and limb mechanics. This project aims to quantify how obesity influences knee-angle trajectories across a series of controlled walking conditions. Thirty-five participants (12 normal-weight, 23 obese) underwent six distinct walking tasks—ranging from preferred and fast speeds to obstacle approaches and crossings at two heights—while equipped with motion sensors on the upper leg, lower leg, and shoes. By comparing knee-angle profiles between obese and non-obese groups, we seek to identify the association between knee angles and people’s body measurements.

In this report, we will mainly talk about the EDA of the dataset, the models used to assess the relationship and interpret our models’ results to reach a final conclusion.

Data Description

## 'data.frame':    2025 obs. of  52 variables:
##  $ Subject      : int  1 1 1 1 1 1 1 1 1 1 ...
##  $ studyid      : int  1 1 1 1 1 1 1 1 1 1 ...
##  $ age          : int  36 36 36 36 36 36 36 36 36 36 ...
##  $ Group        : int  0 0 0 0 0 0 0 0 0 0 ...
##  $ Class        : int  0 0 0 0 0 0 0 0 0 0 ...
##  $ BS           : int  0 0 0 0 0 0 0 0 0 0 ...
##  $ Sex          : int  0 0 0 0 0 0 0 0 0 0 ...
##  $ BMI          : num  20.1 20.1 20.1 20.1 20.1 ...
##  $ Race         : int  0 0 0 0 0 0 0 0 0 0 ...
##  $ height_m     : num  1.66 1.66 1.66 1.66 1.66 1.66 1.66 1.66 1.66 1.66 ...
##  $ weight_kg    : num  55.3 55.3 55.3 55.3 55.3 ...
##  $ leg_l_l      : num  92 92 92 92 92 92 92 92 92 92 ...
##  $ leg_l_r      : num  93 93 93 93 93 93 93 93 93 93 ...
##  $ leg_l        : num  92.5 92.5 92.5 92.5 92.5 92.5 92.5 92.5 92.5 92.5 ...
##  $ DST          : int  22 22 22 22 22 22 22 22 22 22 ...
##  $ Stroop       : int  119 119 119 119 119 119 119 119 119 119 ...
##  $ Stroop_Effect: num  483 483 483 483 483 ...
##  $ PA           : num  7.12 7.12 7.12 7.12 7.12 ...
##  $ Task         : chr  "PRF" "PRF" "PRF" "PRF" ...
##  $ Trial        : int  1 2 3 4 1 2 3 4 1 2 ...
##  $ Speed        : num  1.29 1.32 1.32 1.32 1.55 1.51 1.57 1.53 1.4 1.35 ...
##  $ Initial      : num  4.5 3.63 3.22 3.95 6.88 ...
##  $ Peak         : num  10.4 11.8 10.1 12.8 16.3 ...
##  $ InitialPeak  : num  5.9 8.21 6.93 8.83 9.47 ...
##  $ Min          : num  1.4 1.51 1.59 2.34 1.5 ...
##  $ MinPeak      : num  9 10.33 8.56 10.44 14.84 ...
##  $ Stiffness    : num  0.1153 0.1114 0.0969 0.0902 0.1088 ...
##  $ MomentPeak   : num  0.518 0.738 0.553 0.705 0.748 ...
##  $ kneeMrange   : num  0.75 0.925 0.647 0.771 0.992 ...
##  $ head_cir     : num  56.5 56.5 56.5 56.5 56.5 56.5 56.5 56.5 56.5 56.5 ...
##  $ neck_cir     : num  36 36 36 36 36 36 36 36 36 36 ...
##  $ SH_B         : num  34.6 34.6 34.6 34.6 34.6 34.6 34.6 34.6 34.6 34.6 ...
##  $ SH_D         : num  19 19 19 19 19 19 19 19 19 19 ...
##  $ CH_B         : num  26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 ...
##  $ CH_D         : num  18 18 18 18 18 18 18 18 18 18 ...
##  $ WA_B         : num  23 23 23 23 23 23 23 23 23 23 ...
##  $ WA_D         : num  19 19 19 19 19 19 19 19 19 19 ...
##  $ HIP_B        : num  29.4 29.4 29.4 29.4 29.4 29.4 29.4 29.4 29.4 29.4 ...
##  $ HIP_D        : num  20.5 20.5 20.5 20.5 20.5 20.5 20.5 20.5 20.5 20.5 ...
##  $ ASIS         : num  21.3 21.3 21.3 21.3 21.3 21.3 21.3 21.3 21.3 21.3 ...
##  $ waist_cir    : num  76 76 76 76 76 76 76 76 76 76 ...
##  $ hip_cir      : num  90 90 90 90 90 90 90 90 90 90 ...
##  $ thigh_cir    : num  49 49 49 49 49 49 49 49 49 49 ...
##  $ L_thigh_cir  : num  35 35 35 35 35 35 35 35 35 35 ...
##  $ shank_cir    : num  29 29 29 29 29 29 29 29 29 29 ...
##  $ ankle_cir    : num  21 21 21 21 21 21 21 21 21 21 ...
##  $ W.H.ratio    : num  0.844 0.844 0.844 0.844 0.844 ...
##  $ ABSI         : num  79.8 79.8 79.8 79.8 79.8 ...
##  $ Hip.Index    : num  50.2 50.2 50.2 50.2 50.2 ...
##  $ biceps_cir   : num  26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 26.5 ...
##  $ forearm_cir  : num  23.5 23.5 23.5 23.5 23.5 23.5 23.5 23.5 23.5 23.5 ...
##  $ wrist_cir    : num  15 15 15 15 15 15 15 15 15 15 ...

The main dataset used is “BodyShape.csv”. It contains the body shape measures, such as BMI, hip circumference, waist hip ratio, cognitive test scores, physical activity scores and the knee angle before and after conducting the task and the difference between those two measures for all 38 participants. However, there are many repeated measures for each participants, which means that linear mixed effect model would be a good baseline model to start with. Next, we will perform EDA to select the important variables related to knee angles.

EDA

Based on the histogram, for normal people, the knee angle difference is mostly centered around 10 degrees, for obese people, the knee angle difference is more right tailed, there are more observations distributed around 0 to 5 degrees; for boxplot, the median of obese people is slightly lower than normal people. Both plots have showed that the knee angle difference is smaller for obese group, meaning they tend to bend less their knees during the six walking stances. From the correlation plot above, InitialPeak does not have high correlation with any of the body measurements, also, many of the body measurements are highly correlated with each other, and they are also tend to correlate with Group, Body Shape, BMI and weight. We could further use VIF value to test for the multicollinearity.

## Warning in summary.lm(object, ...): essentially perfect fit: summary may be
## unreliable
##           age         Group         Class            BS           Sex 
##      6.847906     71.981158     99.320093     39.180965     41.588461 
##           BMI          Race      height_m     weight_kg         leg_l 
##   1722.631669      8.040939    146.804583     60.103351     30.476475 
##           DST        Stroop Stroop_Effect            PA         Speed 
##      6.176927      6.628922      8.074536      6.408408      3.649911 
##       Initial          Peak           Min       MinPeak     Stiffness 
##      2.962855    397.294243    191.851953    309.612294      1.528218 
##    MomentPeak    kneeMrange      neck_cir          SH_B          SH_D 
##     31.754977     24.552982     19.213967      9.284384     34.179679 
##          CH_B          CH_D          WA_B          WA_D         HIP_B 
##     16.135450     36.112680     36.035933     46.457726     27.415390 
##         HIP_D          ASIS     waist_cir       hip_cir     thigh_cir 
##     44.179809     10.930804   8221.128851   4914.450223     37.235729 
##   L_thigh_cir     shank_cir     ankle_cir     W.H.ratio          ABSI 
##     16.264640     36.981547     24.051762   2683.961251     47.511878 
##     Hip.Index 
##     17.390758

The values above are the values of VIF, and it is clear that most of the body measurement are high correlated with each other since many of the VIF values are far exceeding 10. We will try to remove some of the variables to see if VIF values change.

## Warning in summary.lm(object, ...): essentially perfect fit: summary may be
## unreliable
##           age         Group           Sex          Race         leg_l 
##      1.778794      9.995250      4.502893      2.044137      1.990723 
##           DST        Stroop Stroop_Effect            PA         Speed 
##      1.840140      2.299483      1.970921      2.141428      2.775249 
##       Initial          Peak           Min       MinPeak     Stiffness 
##      2.066236    376.571767    183.235431    293.522531      1.382954 
##    MomentPeak    kneeMrange      neck_cir          SH_B          CH_B 
##     15.834178     13.863525      6.013996      3.475902      4.883854 
##          WA_B         HIP_D          ASIS     shank_cir     ankle_cir 
##      6.438265      8.361000      4.826496      6.084880      5.056890 
##          ABSI 
##      2.166755

As the results shown above, after removing leg_l_l, leg_l_r, BMI, waist_cir, hip_cir, thigh_cir, height_m, weight_kg, W.H.ratio, Hip.Index, WA_B, WA_D, BS, SH_D and CH_D, most of the VIF become lower than 10, thus, we will try include those variables in the later modeling part.

## Warning: Removed 6 rows containing non-finite outside the scale range
## (`stat_boxplot()`).
## Warning: Removed 6 rows containing missing values or values outside the scale range
## (`geom_point()`).

## Warning: Removed 6 rows containing non-finite outside the scale range
## (`stat_boxplot()`).
## Warning: Removed 6 rows containing missing values or values outside the scale range
## (`geom_point()`).


Based on the boxplot shown above, both groups bent their knees the most when they walk fast, and for all six tasks, people in normal group tend to have greater knee angle difference than the obese group.

Modeling

Model 1: Stiffness

library(lmerTest)
## 
## Attaching package: 'lmerTest'
## The following object is masked from 'package:lme4':
## 
##     lmer
## The following object is masked from 'package:stats':
## 
##     step
m1 <- lmer(Stiffness
 ~ factor(BS)+age+leg_l+factor(Race)+Speed+(1|Subject), data=df_ocha)
summary(m1)
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Stiffness ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocha
## 
## REML criterion at convergence: -593.5
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -2.6900 -0.3168 -0.0515  0.2125  6.8678 
## 
## Random effects:
##  Groups   Name        Variance  Std.Dev.
##  Subject  (Intercept) 0.0008254 0.02873 
##  Residual             0.0027145 0.05210 
## Number of obs: 225, groups:  Subject, 30
## 
## Fixed effects:
##                Estimate Std. Error        df t value Pr(>|t|)   
## (Intercept)    0.075306   0.126874 18.308566   0.594  0.56008   
## factor(BS)1   -0.043521   0.021287 19.691852  -2.045  0.05450 . 
## factor(BS)2   -0.060763   0.016466 19.445403  -3.690  0.00151 **
## age            0.000289   0.001689 18.426326   0.171  0.86599   
## leg_l         -0.001685   0.001563 23.019037  -1.078  0.29210   
## factor(Race)1  0.002302   0.025337 18.649465   0.091  0.92859   
## factor(Race)2 -0.001789   0.025430 20.572824  -0.070  0.94461   
## factor(Race)3  0.064453   0.027126 18.681403   2.376  0.02836 * 
## factor(Race)4 -0.012498   0.029953 20.846463  -0.417  0.68077   
## Speed          0.118924   0.046888 60.491145   2.536  0.01380 * 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.141                                                        
## factor(BS)2  0.000  0.472                                                 
## age         -0.182 -0.546 -0.119                                          
## leg_l       -0.847  0.153 -0.161 -0.113                                   
## factor(Rc)1 -0.166  0.319  0.089 -0.073  0.114                            
## factor(Rc)2 -0.128  0.140  0.024 -0.103  0.144  0.749                     
## factor(Rc)3 -0.151  0.234  0.060 -0.048  0.111  0.742  0.696              
## factor(Rc)4 -0.177 -0.048 -0.057  0.188  0.180  0.653  0.658  0.617       
## Speed        0.017  0.111  0.282  0.003 -0.437 -0.218 -0.306 -0.226 -0.430
r2 <- r.squaredGLMM(m1)
print(r2)
##            R2m       R2c
## [1,] 0.3543964 0.5049386
# 95% Confidence Intervals for fixed effects (beta coefficients)
ci <- confint(m1, level = 0.95, method = "Wald")  # Or method = "profile"
print(ci)
##                      2.5 %       97.5 %
## .sig01                  NA           NA
## .sigma                  NA           NA
## (Intercept)   -0.173362427  0.323973593
## factor(BS)1   -0.085242627 -0.001800058
## factor(BS)2   -0.093035933 -0.028489441
## age           -0.003020904  0.003598884
## leg_l         -0.004748523  0.001378079
## factor(Race)1 -0.047357474  0.051960808
## factor(Race)2 -0.051629758  0.048052539
## factor(Race)3  0.011287693  0.117617831
## factor(Race)4 -0.071204718  0.046209445
## Speed          0.027025529  0.210822001

Model 2: Peak Knee Angle

m2 <- lmer(Peak ~ factor(BS)+age+leg_l+factor(Race)+Speed+(1|Subject), data=df_ocha)
summary(m2)
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Peak ~ factor(BS) + age + leg_l + factor(Race) + Speed + (1 |  
##     Subject)
##    Data: df_ocha
## 
## REML criterion at convergence: 1209.4
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.2792 -0.5176 -0.0294  0.5801  3.3780 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 44.520   6.672   
##  Residual              8.727   2.954   
## Number of obs: 228, groups:  Subject, 30
## 
## Fixed effects:
##               Estimate Std. Error       df t value Pr(>|t|)    
## (Intercept)    21.6647    24.6589  20.9291   0.879 0.389607    
## factor(BS)1    -9.6998     4.0482  21.1049  -2.396 0.025915 *  
## factor(BS)2   -13.3625     3.1062  21.3460  -4.302 0.000306 ***
## age             0.3798     0.3276  20.9418   1.159 0.259420    
## leg_l          -0.3173     0.2757  22.5107  -1.151 0.261797    
## factor(Race)1   2.0431     4.8469  21.2178   0.422 0.677614    
## factor(Race)2   1.7259     4.7125  21.6080   0.366 0.717748    
## factor(Race)3   4.7502     5.1871  21.2374   0.916 0.370076    
## factor(Race)4   3.6106     5.4094  22.2288   0.667 0.511340    
## Speed          11.7757     3.6313 217.7806   3.243 0.001370 ** 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.098                                                        
## factor(BS)2  0.011  0.462                                                 
## age         -0.228 -0.534 -0.104                                          
## leg_l       -0.917  0.163 -0.087 -0.076                                   
## factor(Rc)1 -0.140  0.352  0.153 -0.084  0.014                            
## factor(Rc)2 -0.097  0.176  0.112 -0.116  0.006  0.742                     
## factor(Rc)3 -0.124  0.258  0.109 -0.050  0.006  0.727  0.682              
## factor(Rc)4 -0.179 -0.002  0.057  0.192  0.025  0.629  0.620  0.587       
## Speed        0.008  0.036  0.109  0.007 -0.193 -0.092 -0.128 -0.095 -0.187
r2 <- r.squaredGLMM(m2)
print(r2)
##            R2m       R2c
## [1,] 0.4482139 0.9095632
# 95% Confidence Intervals for fixed effects (beta coefficients)
ci <- confint(m2, level = 0.95, method = "Wald")  # Or method = "profile"
print(ci)
##                     2.5 %     97.5 %
## .sig01                 NA         NA
## .sigma                 NA         NA
## (Intercept)   -26.6658830 69.9953302
## factor(BS)1   -17.6340629 -1.7654624
## factor(BS)2   -19.4504242 -7.2745101
## age            -0.2623566  1.0219505
## leg_l          -0.8576983  0.2230198
## factor(Race)1  -7.4567002 11.5428567
## factor(Race)2  -7.5104088 10.9622114
## factor(Race)3  -5.4164534 14.9167714
## factor(Race)4  -6.9915969 14.2128672
## Speed           4.6584134 18.8929001

Model 3: Initial_Peak Knee Angle Difference

m3 <- lmer(InitialPeak ~ factor(BS)+age+leg_l+factor(Race)+Speed+(1|Subject), data=df_ocha)
summary(m3)
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: InitialPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocha
## 
## REML criterion at convergence: 1154.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.5716 -0.5119  0.0265  0.5108  3.2914 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 23.996   4.899   
##  Residual              7.055   2.656   
## Number of obs: 228, groups:  Subject, 30
## 
## Fixed effects:
##               Estimate Std. Error       df t value Pr(>|t|)  
## (Intercept)    28.6316    18.2266  20.8257   1.571   0.1313  
## factor(BS)1    -5.9192     2.9952  21.0774  -1.976   0.0614 .
## factor(BS)2    -6.3489     2.3011  21.3908  -2.759   0.0116 *
## age             0.1713     0.2422  20.8440   0.707   0.4871  
## leg_l          -0.3647     0.2055  22.9906  -1.775   0.0891 .
## factor(Race)1  -1.0532     3.5882  21.2099  -0.294   0.7720  
## factor(Race)2   1.1469     3.4960  21.7536   0.328   0.7460  
## factor(Race)3   1.1039     3.8404  21.2379   0.287   0.7766  
## factor(Race)4   5.7272     4.0255  22.5793   1.423   0.1685  
## Speed           3.9267     3.1991 216.1422   1.227   0.2210  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.099                                                        
## factor(BS)2  0.011  0.462                                                 
## age         -0.226 -0.535 -0.104                                          
## leg_l       -0.911  0.161 -0.094 -0.078                                   
## factor(Rc)1 -0.141  0.349  0.148 -0.084  0.022                            
## factor(Rc)2 -0.099  0.173  0.105 -0.116  0.018  0.743                     
## factor(Rc)3 -0.125  0.256  0.105 -0.051  0.015  0.728  0.684              
## factor(Rc)4 -0.179 -0.005  0.048  0.190  0.040  0.631  0.624  0.589       
## Speed        0.010  0.043  0.130  0.008 -0.228 -0.109 -0.152 -0.113 -0.221
r2 <- r.squaredGLMM(m3)
print(r2)
##            R2m       R2c
## [1,] 0.3177622 0.8449954
# 95% Confidence Intervals for fixed effects (beta coefficients)
ci <- confint(m3, level = 0.95, method = "Wald")  # Or method = "profile"
print(ci)
##                     2.5 %      97.5 %
## .sig01                 NA          NA
## .sigma                 NA          NA
## (Intercept)    -7.0918682 64.35510008
## factor(BS)1   -11.7896486 -0.04883345
## factor(BS)2   -10.8589798 -1.83887138
## age            -0.3033504  0.64601132
## leg_l          -0.7674139  0.03798025
## factor(Race)1  -8.0859176  5.97942185
## factor(Race)2  -5.7050410  7.99883291
## factor(Race)3  -6.4231926  8.63108304
## factor(Race)4  -2.1626765 13.61706818
## Speed          -2.3434518 10.19690687
# Calculate marginal and conditional R²
r2 <- r.squaredGLMM(m3)
print(r2)
##            R2m       R2c
## [1,] 0.3177622 0.8449954

Since SH_B(Shoulder Breadth), CH_B(Chest Breadth), L_thigh_cir(lower thigh circumference), shank_cir(shank circumference) and ABSI(a body shape index) are the only statistically significant variables based on the model output above. We can try only including those variables as fixed effects and check the performance using ANOVA later.

Model 4: Moment Peak

## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: MomentPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocha
## 
## REML criterion at convergence: -162.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.0445 -0.5343  0.0231  0.4568  3.7881 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.05631  0.2373  
##  Residual             0.01648  0.1284  
## Number of obs: 225, groups:  Subject, 30
## 
## Fixed effects:
##                Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)     1.05077    0.88296  20.86307   1.190 0.247391    
## factor(BS)1    -0.43776    0.14521  21.17799  -3.015 0.006555 ** 
## factor(BS)2    -0.46792    0.11158  21.50135  -4.194 0.000392 ***
## age             0.01443    0.01173  20.88662   1.230 0.232324    
## leg_l          -0.01657    0.00996  23.07367  -1.664 0.109606    
## factor(Race)1   0.06631    0.17389  21.27186   0.381 0.706711    
## factor(Race)2   0.10023    0.16949  21.84945   0.591 0.560345    
## factor(Race)3   0.16783    0.18606  21.27891   0.902 0.377152    
## factor(Race)4   0.28019    0.19522  22.69371   1.435 0.164846    
## Speed           0.52236    0.15849 212.90505   3.296 0.001150 ** 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.100                                                        
## factor(BS)2  0.010  0.463                                                 
## age         -0.226 -0.535 -0.105                                          
## leg_l       -0.910  0.160 -0.095 -0.078                                   
## factor(Rc)1 -0.141  0.348  0.147 -0.083  0.023                            
## factor(Rc)2 -0.099  0.172  0.104 -0.115  0.019  0.743                     
## factor(Rc)3 -0.125  0.256  0.104 -0.050  0.015  0.728  0.684              
## factor(Rc)4 -0.178 -0.007  0.046  0.191  0.042  0.631  0.624  0.589       
## Speed        0.008  0.050  0.136  0.004 -0.231 -0.113 -0.156 -0.115 -0.226
##            R2m       R2c
## [1,] 0.4748231 0.8811105
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   1.995822  2        1.188586
## age          1.648239  1        1.283838
## leg_l        1.138110  1        1.066822
## factor(Race) 1.571311  4        1.058115
## Speed        1.140020  1        1.067717
##                      2.5 %       97.5 %
## .sig01                  NA           NA
## .sigma                  NA           NA
## (Intercept)   -0.679796138  2.781333479
## factor(BS)1   -0.722367270 -0.153159230
## factor(BS)2   -0.686606058 -0.249226485
## age           -0.008563237  0.037429848
## leg_l         -0.036095713  0.002946269
## factor(Race)1 -0.274494396  0.407123758
## factor(Race)2 -0.231962747  0.432422607
## factor(Race)3 -0.196844285  0.532498556
## factor(Race)4 -0.102426962  0.662814218
## Speed          0.211713955  0.833004753

Model 5: Moment Range

## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: kneeMrange ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocha
## 
## REML criterion at convergence: -133.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -2.6250 -0.4440 -0.0591  0.5449  3.6850 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.02721  0.1649  
##  Residual             0.02060  0.1435  
## Number of obs: 225, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)     0.644426   0.633055  20.494570   1.018 0.320563    
## factor(BS)1    -0.413719   0.104634  21.167222  -3.954 0.000716 ***
## factor(BS)2    -0.457539   0.080722  21.588858  -5.668 1.14e-05 ***
## age             0.011283   0.008416  20.546939   1.341 0.194629    
## leg_l          -0.009949   0.007353  24.356264  -1.353 0.188508    
## factor(Race)1  -0.017367   0.125365  21.123383  -0.139 0.891134    
## factor(Race)2   0.005427   0.123214  22.230830   0.044 0.965258    
## factor(Race)3   0.014412   0.134160  21.142097   0.107 0.915466    
## factor(Race)4   0.227688   0.143365  23.482062   1.588 0.125625    
## Speed           0.628287   0.163080 163.804191   3.853 0.000167 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.109                                                        
## factor(BS)2  0.008  0.466                                                 
## age         -0.217 -0.537 -0.107                                          
## leg_l       -0.887  0.153 -0.120 -0.085                                   
## factor(Rc)1 -0.146  0.339  0.128 -0.082  0.053                            
## factor(Rc)2 -0.105  0.162  0.078 -0.113  0.061  0.746                     
## factor(Rc)3 -0.130  0.248  0.088 -0.050  0.047  0.733  0.688              
## factor(Rc)4 -0.177 -0.020  0.012  0.188  0.092  0.638  0.636  0.598       
## Speed        0.012  0.073  0.194  0.005 -0.322 -0.159 -0.220 -0.163 -0.316
##            R2m       R2c
## [1,] 0.5761764 0.8173572
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.046464  2        1.196055
## age          1.653760  1        1.285986
## leg_l        1.206084  1        1.098219
## factor(Race) 1.664657  4        1.065775
## Speed        1.289762  1        1.135677
##                      2.5 %       97.5 %
## .sig01                  NA           NA
## .sigma                  NA           NA
## (Intercept)   -0.596339452  1.885191838
## factor(BS)1   -0.618797726 -0.208639357
## factor(BS)2   -0.615751951 -0.299325803
## age           -0.005210833  0.027777736
## leg_l         -0.024361171  0.004463902
## factor(Race)1 -0.263078553  0.228344841
## factor(Race)2 -0.236067208  0.246922146
## factor(Race)3 -0.248536582  0.277360331
## factor(Race)4 -0.053303536  0.508678771
## Speed          0.308655233  0.947918753
## Residual analysis for Stiffness

## 
## 
## Residual analysis for Peak

## 
## 
## Residual analysis for InitialPeak

## 
## 
## Residual analysis for PeakMoment

## 
## 
## Residual analysis for kneeRange

## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Stiffness ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocma
## 
## REML criterion at convergence: -402.6
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -1.5780 -0.1687 -0.0396  0.0881 13.3630 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.001999 0.04471 
##  Residual             0.007487 0.08653 
## Number of obs: 238, groups:  Subject, 30
## 
## Fixed effects:
##                Estimate Std. Error        df t value Pr(>|t|)
## (Intercept)    0.259214   0.196080 17.952438   1.322    0.203
## factor(BS)1    0.009513   0.033957 20.753437   0.280    0.782
## factor(BS)2   -0.027236   0.027144 20.865841  -1.003    0.327
## age           -0.002472   0.002666 19.613698  -0.927    0.365
## leg_l         -0.003475   0.002521 21.976076  -1.378    0.182
## factor(Race)1  0.022579   0.040634 20.463141   0.556    0.584
## factor(Race)2  0.016806   0.041476 22.950912   0.405    0.689
## factor(Race)3  0.073138   0.044218 21.157487   1.654    0.113
## factor(Race)4 -0.016071   0.047503 21.317920  -0.338    0.738
## Speed          0.125155   0.081937 37.905511   1.527    0.135
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.101                                                        
## factor(BS)2  0.024  0.509                                                 
## age         -0.206 -0.527 -0.107                                          
## leg_l       -0.817  0.056 -0.253 -0.110                                   
## factor(Rc)1 -0.142  0.267  0.046 -0.091  0.124                            
## factor(Rc)2 -0.110  0.081 -0.035 -0.124  0.178  0.766                     
## factor(Rc)3 -0.142  0.168 -0.007 -0.068  0.150  0.745  0.710              
## factor(Rc)4 -0.172 -0.094 -0.105  0.154  0.202  0.675  0.685  0.636       
## Speed        0.035  0.208  0.401  0.046 -0.512 -0.264 -0.372 -0.290 -0.431
##            R2m       R2c
## [1,] 0.1316237 0.3146344
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.345072  2        1.237482
## age          1.662664  1        1.289443
## leg_l        1.474573  1        1.214320
## factor(Race) 1.863030  4        1.080880
## Speed        1.910343  1        1.382152
##                      2.5 %      97.5 %
## .sig01                  NA          NA
## .sigma                  NA          NA
## (Intercept)   -0.125094906 0.643523360
## factor(BS)1   -0.057041295 0.076067256
## factor(BS)2   -0.080436451 0.025964990
## age           -0.007697637 0.002753231
## leg_l         -0.008415494 0.001465964
## factor(Race)1 -0.057063479 0.102220811
## factor(Race)2 -0.064484601 0.098096461
## factor(Race)3 -0.013528316 0.159804990
## factor(Race)4 -0.109175585 0.077033126
## Speed         -0.035438836 0.285748285
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Peak ~ factor(BS) + age + leg_l + factor(Race) + Speed + (1 |  
##     Subject)
##    Data: df_ocma
## 
## REML criterion at convergence: 1278.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -5.2526 -0.4295 -0.0235  0.4249  3.7690 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 46.711   6.835   
##  Residual              9.039   3.006   
## Number of obs: 240, groups:  Subject, 30
## 
## Fixed effects:
##               Estimate Std. Error       df t value Pr(>|t|)    
## (Intercept)    30.8178    25.2027  20.7003   1.223 0.235146    
## factor(BS)1    -7.3740     4.1611  21.2843  -1.772 0.090691 .  
## factor(BS)2    -9.9505     3.2246  22.2193  -3.086 0.005360 ** 
## age             0.2467     0.3354  20.8470   0.736 0.470183    
## leg_l          -0.4680     0.2868  23.4682  -1.632 0.116079    
## factor(Race)1   1.4443     4.9790  21.3461   0.290 0.774560    
## factor(Race)2   0.1026     4.8649  22.0820   0.021 0.983368    
## factor(Race)3   2.5832     5.3448  21.5903   0.483 0.633736    
## factor(Race)4   1.7485     5.5742  22.5009   0.314 0.756661    
## Speed          16.8159     4.8864 216.6442   3.441 0.000694 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.093                                                        
## factor(BS)2  0.014  0.471                                                 
## age         -0.230 -0.529 -0.099                                          
## leg_l       -0.903  0.136 -0.118 -0.078                                   
## factor(Rc)1 -0.138  0.339  0.136 -0.087  0.027                            
## factor(Rc)2 -0.096  0.159  0.088 -0.119  0.028  0.745                     
## factor(Rc)3 -0.123  0.243  0.087 -0.054  0.025  0.729  0.687              
## factor(Rc)4 -0.179 -0.018  0.033  0.185  0.047  0.633  0.628  0.593       
## Speed        0.015  0.103  0.199  0.022 -0.267 -0.125 -0.181 -0.143 -0.219
##           R2m      R2c
## [1,] 0.378309 0.899203
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.033846  2        1.194207
## age          1.645912  1        1.282931
## leg_l        1.158645  1        1.076404
## factor(Race) 1.569484  4        1.057961
## Speed        1.197344  1        1.094232
##                     2.5 %      97.5 %
## .sig01                 NA          NA
## .sigma                 NA          NA
## (Intercept)   -18.5786417 80.21425361
## factor(BS)1   -15.5295564  0.78164662
## factor(BS)2   -16.2706019 -3.63036277
## age            -0.4106695  0.90410847
## leg_l          -1.0301388  0.09413347
## factor(Race)1  -8.3144032 11.20294969
## factor(Race)2  -9.4325245  9.63767306
## factor(Race)3  -7.8924019 13.05888456
## factor(Race)4  -9.1768429 12.67379817
## Speed           7.2386942 26.39313968
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: InitialPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocma
## 
## REML criterion at convergence: 1205.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -4.1712 -0.5701  0.0326  0.5264  3.6932 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 20.488   4.526   
##  Residual              6.894   2.626   
## Number of obs: 240, groups:  Subject, 30
## 
## Fixed effects:
##                Estimate Std. Error        df t value Pr(>|t|)  
## (Intercept)    34.63678   16.83172  20.18115   2.058   0.0528 .
## factor(BS)1    -4.29280    2.79167  21.03059  -1.538   0.1390  
## factor(BS)2    -5.07396    2.17749  22.24728  -2.330   0.0293 *
## age             0.09442    0.22428  20.42259   0.421   0.6781  
## leg_l          -0.42532    0.19525  23.90934  -2.178   0.0395 *
## factor(Race)1   0.65003    3.34170  21.08859   0.195   0.8476  
## factor(Race)2   1.29077    3.28259  22.12878   0.393   0.6979  
## factor(Race)3   1.62470    3.59368  21.43276   0.452   0.6557  
## factor(Race)4   6.63053    3.77119  22.61646   1.758   0.0922 .
## Speed           4.41487    4.04269 175.81807   1.092   0.2763  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.093                                                        
## factor(BS)2  0.016  0.476                                                 
## age         -0.228 -0.528 -0.098                                          
## leg_l       -0.888  0.120 -0.142 -0.081                                   
## factor(Rc)1 -0.138  0.329  0.121 -0.088  0.044                            
## factor(Rc)2 -0.097  0.148  0.068 -0.121  0.053  0.748                     
## factor(Rc)3 -0.124  0.232  0.071 -0.056  0.046  0.731  0.690              
## factor(Rc)4 -0.178 -0.030  0.010  0.180  0.075  0.638  0.636  0.599       
## Speed        0.019  0.127  0.243  0.027 -0.325 -0.155 -0.223 -0.177 -0.268
##            R2m       R2c
## [1,] 0.3428894 0.8345491
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.077662  2        1.200587
## age          1.646845  1        1.283295
## leg_l        1.203498  1        1.097040
## factor(Race) 1.615001  4        1.061748
## Speed        1.302817  1        1.141410
##                    2.5 %      97.5 %
## .sig01                NA          NA
## .sigma                NA          NA
## (Intercept)    1.6472172 67.62633799
## factor(BS)1   -9.7643795  1.17878107
## factor(BS)2   -9.3417553 -0.80616007
## age           -0.3451593  0.53400789
## leg_l         -0.8079922 -0.04264462
## factor(Race)1 -5.8995790  7.19964318
## factor(Race)2 -5.1429898  7.72452028
## factor(Race)3 -5.4187842  8.66818640
## factor(Race)4 -0.7608625 14.02193152
## Speed         -3.5086526 12.33838710
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: MomentPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocma
## 
## REML criterion at convergence: -182.9
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.8305 -0.5319  0.0567  0.4540  3.1528 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.06926  0.2632  
##  Residual             0.01586  0.1260  
## Number of obs: 239, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)     1.344732   0.972519  20.487492   1.383 0.181635    
## factor(BS)1    -0.349821   0.160794  21.160429  -2.176 0.041061 *  
## factor(BS)2    -0.370858   0.124850  22.196168  -2.970 0.007018 ** 
## age             0.006448   0.012947  20.660576   0.498 0.623748    
## leg_l          -0.019946   0.011127  23.547824  -1.793 0.085889 .  
## factor(Race)1   0.050559   0.192401  21.213844   0.263 0.795257    
## factor(Race)2   0.066557   0.188256  22.032288   0.354 0.727040    
## factor(Race)3   0.158225   0.206623  21.481237   0.766 0.452148    
## factor(Race)4   0.202765   0.215884  22.484973   0.939 0.357594    
## Speed           0.680171   0.202215 206.545771   3.364 0.000917 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.093                                                        
## factor(BS)2  0.014  0.473                                                 
## age         -0.230 -0.529 -0.099                                          
## leg_l       -0.899  0.131 -0.125 -0.078                                   
## factor(Rc)1 -0.138  0.336  0.132 -0.087  0.032                            
## factor(Rc)2 -0.096  0.156  0.082 -0.120  0.035  0.746                     
## factor(Rc)3 -0.123  0.240  0.083 -0.054  0.031  0.729  0.688              
## factor(Rc)4 -0.178 -0.022  0.026  0.184  0.055  0.634  0.630  0.594       
## Speed        0.016  0.111  0.213  0.023 -0.285 -0.134 -0.193 -0.153 -0.234
##            R2m       R2c
## [1,] 0.4090695 0.8898725
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.046819  2        1.196107
## age          1.646257  1        1.283066
## leg_l        1.170973  1        1.082115
## factor(Race) 1.581932  4        1.059006
## Speed        1.227068  1        1.107731
##                     2.5 %       97.5 %
## .sig01                 NA           NA
## .sigma                 NA           NA
## (Intercept)   -0.56137045  3.250834321
## factor(BS)1   -0.66497180 -0.034670511
## factor(BS)2   -0.61555901 -0.126156270
## age           -0.01892833  0.031823503
## leg_l         -0.04175337  0.001861782
## factor(Race)1 -0.32653994  0.427656993
## factor(Race)2 -0.30241705  0.435531038
## factor(Race)3 -0.24674938  0.563199790
## factor(Race)4 -0.22036086  0.625890183
## Speed          0.28383688  1.076504433
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: kneeMrange ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocma
## 
## REML criterion at convergence: -143.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.2938 -0.5617  0.0128  0.5080  3.5606 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.04213  0.2053  
##  Residual             0.02009  0.1417  
## Number of obs: 239, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)    1.096e+00  7.695e-01  2.010e+01   1.424  0.16986    
## factor(BS)1   -3.004e-01  1.282e-01  2.118e+01  -2.344  0.02891 *  
## factor(BS)2   -3.261e-01  1.005e-01  2.255e+01  -3.246  0.00363 ** 
## age           -7.318e-04  1.027e-02  2.043e+01  -0.071  0.94387    
## leg_l         -1.609e-02  9.057e-03  2.439e+01  -1.777  0.08808 .  
## factor(Race)1 -7.779e-02  1.534e-01  2.120e+01  -0.507  0.61733    
## factor(Race)2 -6.729e-02  1.513e-01  2.245e+01  -0.445  0.66082    
## factor(Race)3 -4.557e-02  1.652e-01  2.161e+01  -0.276  0.78526    
## factor(Race)4  6.643e-02  1.742e-01  2.293e+01   0.381  0.70639    
## Speed          9.537e-01  2.088e-01  1.415e+02   4.568 1.06e-05 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.093                                                        
## factor(BS)2  0.017  0.481                                                 
## age         -0.227 -0.526 -0.098                                          
## leg_l       -0.877  0.108 -0.160 -0.083                                   
## factor(Rc)1 -0.139  0.321  0.110 -0.089  0.057                            
## factor(Rc)2 -0.098  0.138  0.052 -0.121  0.072  0.750                     
## factor(Rc)3 -0.126  0.224  0.059 -0.057  0.061  0.733  0.693              
## factor(Rc)4 -0.177 -0.039 -0.009  0.176  0.096  0.642  0.642  0.603       
## Speed        0.021  0.144  0.274  0.030 -0.361 -0.175 -0.250 -0.198 -0.300
##            R2m       R2c
## [1,] 0.4938239 0.8365632
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.113744  2        1.205766
## age          1.647880  1        1.283698
## leg_l        1.238722  1        1.112979
## factor(Race) 1.650431  4        1.064632
## Speed        1.386599  1        1.177539
##                     2.5 %       97.5 %
## .sig01                 NA           NA
## .sigma                 NA           NA
## (Intercept)   -0.41262052  2.603836255
## factor(BS)1   -0.55159333 -0.049203897
## factor(BS)2   -0.52304063 -0.129216342
## age           -0.02085329  0.019389781
## leg_l         -0.03384468  0.001658975
## factor(Race)1 -0.37846485  0.222883334
## factor(Race)2 -0.36386957  0.229295382
## factor(Race)3 -0.36934447  0.278198213
## factor(Race)4 -0.27491489  0.407776099
## Speed          0.54444966  1.362876635
## Residual analysis for Stiffness

## 
## 
## Residual analysis for Peak

## 
## 
## Residual analysis for InitialPeak

## 
## 
## Residual analysis for PeakMoment

## 
## 
## Residual analysis for kneeRange

## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Stiffness ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ochb
## 
## REML criterion at convergence: -1057.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.0449 -0.4633 -0.0451  0.2852  4.1364 
## 
## Random effects:
##  Groups   Name        Variance  Std.Dev.
##  Subject  (Intercept) 0.0011660 0.03415 
##  Residual             0.0004871 0.02207 
## Number of obs: 253, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)   
## (Intercept)    7.126e-03  1.277e-01  2.093e+01   0.056  0.95602   
## factor(BS)1    2.135e-02  2.132e-02  2.227e+01   1.001  0.32743   
## factor(BS)2    5.850e-03  1.667e-02  2.373e+01   0.351  0.72873   
## age           -2.743e-03  1.700e-03  2.112e+01  -1.614  0.12140   
## leg_l          7.079e-04  1.470e-03  2.432e+01   0.482  0.63432   
## factor(Race)1 -4.025e-03  2.516e-02  2.137e+01  -0.160  0.87442   
## factor(Race)2  6.203e-03  2.458e-02  2.205e+01   0.252  0.80306   
## factor(Race)3  9.719e-03  2.697e-02  2.155e+01   0.360  0.72209   
## factor(Race)4 -8.979e-03  2.823e-02  2.261e+01  -0.318  0.75338   
## Speed          6.949e-02  2.652e-02  1.932e+02   2.621  0.00947 **
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.086                                                        
## factor(BS)2  0.021  0.488                                                 
## age         -0.226 -0.523 -0.097                                          
## leg_l       -0.902  0.105 -0.147 -0.081                                   
## factor(Rc)1 -0.140  0.325  0.124 -0.086  0.028                            
## factor(Rc)2 -0.101  0.145  0.074 -0.120  0.032  0.745                     
## factor(Rc)3 -0.126  0.236  0.086 -0.055  0.022  0.727  0.684              
## factor(Rc)4 -0.183 -0.038  0.011  0.185  0.054  0.632  0.627  0.587       
## Speed        0.045  0.186  0.286  0.020 -0.303 -0.116 -0.171 -0.113 -0.221
##           R2m       R2c
## [1,] 0.153847 0.7506696
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.131945  2        1.208353
## age          1.647853  1        1.283687
## leg_l        1.183640  1        1.087952
## factor(Race) 1.567707  4        1.057811
## Speed        1.295325  1        1.138123
##                      2.5 %       97.5 %
## .sig01                  NA           NA
## .sigma                  NA           NA
## (Intercept)   -0.243085187 0.2573364060
## factor(BS)1   -0.020439885 0.0631384874
## factor(BS)2   -0.026821888 0.0385217482
## age           -0.006073736 0.0005882379
## leg_l         -0.002172267 0.0035879839
## factor(Race)1 -0.053336642 0.0452875951
## factor(Race)2 -0.041964878 0.0543713137
## factor(Race)3 -0.043143524 0.0625817463
## factor(Race)4 -0.064316896 0.0463580309
## Speed          0.017521683 0.1214595858
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Peak ~ factor(BS) + age + leg_l + factor(Race) + Speed + (1 |  
##     Subject)
##    Data: df_ochb
## 
## REML criterion at convergence: 1034.6
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.1431 -0.6256 -0.0559  0.5943  3.3581 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 22.581   4.752   
##  Residual              2.337   1.529   
## Number of obs: 254, groups:  Subject, 30
## 
## Fixed effects:
##                Estimate Std. Error        df t value Pr(>|t|)   
## (Intercept)    26.16203   17.43275  20.74503   1.501  0.14849   
## factor(BS)1    -3.35476    2.87234  21.20203  -1.168  0.25579   
## factor(BS)2    -8.08628    2.21279  21.77568  -3.654  0.00141 **
## age            -0.02952    0.23170  20.78580  -0.127  0.89985   
## leg_l          -0.12353    0.19408  21.98725  -0.636  0.53103   
## factor(Race)1   4.25999    3.42010  20.89736   1.246  0.22671   
## factor(Race)2   0.34625    3.31868  21.12727   0.104  0.91789   
## factor(Race)3   2.90366    3.66112  20.93997   0.793  0.43661   
## factor(Race)4   1.70953    3.79020  21.35302   0.451  0.65651   
## Speed           2.92508    2.01366 243.23897   1.453  0.14762   
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.091                                                        
## factor(BS)2  0.015  0.469                                                 
## age         -0.231 -0.530 -0.101                                          
## leg_l       -0.923  0.148 -0.095 -0.075                                   
## factor(Rc)1 -0.138  0.347  0.152 -0.085  0.005                            
## factor(Rc)2 -0.096  0.170  0.111 -0.118 -0.005  0.742                     
## factor(Rc)3 -0.122  0.254  0.108 -0.052 -0.003  0.725  0.681              
## factor(Rc)4 -0.181 -0.009  0.058  0.192  0.010  0.627  0.617  0.583       
## Speed        0.025  0.104  0.164  0.011 -0.175 -0.065 -0.096 -0.063 -0.125
##            R2m       R2c
## [1,] 0.4186347 0.9454745
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.007523  2        1.190324
## age          1.645217  1        1.282660
## leg_l        1.108842  1        1.053016
## factor(Race) 1.510351  4        1.052894
## Speed        1.090995  1        1.044507
##                     2.5 %     97.5 %
## .sig01                 NA         NA
## .sigma                 NA         NA
## (Intercept)    -8.0055445 60.3295993
## factor(BS)1    -8.9844470  2.2749278
## factor(BS)2   -12.4232715 -3.7492857
## age            -0.4836367  0.4245991
## leg_l          -0.5039144  0.2568569
## factor(Race)1  -2.4432800 10.9632516
## factor(Race)2  -6.1582415  6.8507506
## factor(Race)3  -4.2719937 10.0793148
## factor(Race)4  -5.7191231  9.1381857
## Speed          -1.0216141  6.8717815
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: InitialPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ochb
## 
## REML criterion at convergence: 1104.9
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -2.65482 -0.57197  0.00578  0.53647  2.34678 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 16.479   4.059   
##  Residual              3.295   1.815   
## Number of obs: 254, groups:  Subject, 30
## 
## Fixed effects:
##               Estimate Std. Error       df t value Pr(>|t|)  
## (Intercept)    23.4752    14.9805  20.9875   1.567   0.1321  
## factor(BS)1    -4.1866     2.4798  21.7809  -1.688   0.1056  
## factor(BS)2    -4.5258     1.9209  22.7443  -2.356   0.0275 *
## age             0.1318     0.1992  21.0704   0.662   0.5152  
## leg_l          -0.1568     0.1688  23.1187  -0.929   0.3626  
## factor(Race)1   1.2701     2.9436  21.2526   0.431   0.6705  
## factor(Race)2   0.3990     2.8630  21.6568   0.139   0.8905  
## factor(Race)3   1.6541     3.1525  21.3373   0.525   0.6052  
## factor(Race)4   3.8983     3.2770  22.0327   1.190   0.2469  
## Speed          -0.9929     2.3182 238.9786  -0.428   0.6688  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.089                                                        
## factor(BS)2  0.017  0.476                                                 
## age         -0.229 -0.527 -0.099                                          
## leg_l       -0.915  0.132 -0.114 -0.077                                   
## factor(Rc)1 -0.139  0.339  0.142 -0.085  0.013                            
## factor(Rc)2 -0.098  0.161  0.097 -0.119  0.008  0.743                     
## factor(Rc)3 -0.124  0.248  0.100 -0.053  0.006  0.726  0.682              
## factor(Rc)4 -0.182 -0.019  0.041  0.190  0.026  0.629  0.620  0.585       
## Speed        0.034  0.139  0.217  0.015 -0.231 -0.086 -0.128 -0.084 -0.166
##            R2m       R2c
## [1,] 0.2088503 0.8681542
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.051554  2        1.196798
## age          1.645926  1        1.282937
## leg_l        1.135587  1        1.065639
## factor(Race) 1.530993  4        1.054682
## Speed        1.163478  1        1.078646
##                    2.5 %     97.5 %
## .sig01                NA         NA
## .sigma                NA         NA
## (Intercept)   -5.8860385 52.8363479
## factor(BS)1   -9.0469034  0.6736646
## factor(BS)2   -8.2905788 -0.7609267
## age           -0.2585804  0.5222506
## leg_l         -0.4876683  0.1740594
## factor(Race)1 -4.4993229  7.0394328
## factor(Race)2 -5.2124525  6.0104122
## factor(Race)3 -4.5247618  7.8329045
## factor(Race)4 -2.5244654 10.3211009
## Speed         -5.5365510  3.5507181
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: MomentPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ochb
## 
## REML criterion at convergence: -354.1
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -2.4930 -0.5532  0.0234  0.4766  3.9640 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.056079 0.23681 
##  Residual             0.008049 0.08972 
## Number of obs: 253, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)     1.111843   0.870902  20.719788   1.277 0.215847    
## factor(BS)1    -0.142997   0.143806  21.334661  -0.994 0.331185    
## factor(BS)2    -0.229233   0.111056  22.084269  -2.064 0.050949 .  
## age            -0.004521   0.011578  20.780864  -0.390 0.700160    
## leg_l          -0.008993   0.009747  22.348778  -0.923 0.366048    
## factor(Race)1   0.154275   0.170980  20.922331   0.902 0.377168    
## factor(Race)2   0.089568   0.166072  21.224497   0.539 0.595273    
## factor(Race)3   0.271577   0.183059  20.979464   1.484 0.152797    
## factor(Race)4   0.236509   0.189853  21.517890   1.246 0.226251    
## Speed           0.404309   0.116680 242.780073   3.465 0.000627 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.091                                                        
## factor(BS)2  0.016  0.472                                                 
## age         -0.230 -0.529 -0.100                                          
## leg_l       -0.919  0.141 -0.104 -0.075                                   
## factor(Rc)1 -0.139  0.343  0.147 -0.085  0.008                            
## factor(Rc)2 -0.097  0.167  0.105 -0.118  0.001  0.742                     
## factor(Rc)3 -0.123  0.251  0.105 -0.052  0.001  0.726  0.681              
## factor(Rc)4 -0.182 -0.013  0.050  0.191  0.017  0.628  0.618  0.584       
## Speed        0.029  0.121  0.189  0.013 -0.201 -0.075 -0.111 -0.073 -0.144
##            R2m       R2c
## [1,] 0.3535708 0.9188654
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.026960  2        1.193195
## age          1.645670  1        1.282837
## leg_l        1.120396  1        1.058488
## factor(Race) 1.519102  4        1.053655
## Speed        1.122572  1        1.059515
##                     2.5 %      97.5 %
## .sig01                 NA          NA
## .sigma                 NA          NA
## (Intercept)   -0.59509252  2.81877949
## factor(BS)1   -0.42485224  0.13885745
## factor(BS)2   -0.44689823 -0.01156680
## age           -0.02721278  0.01817116
## leg_l         -0.02809663  0.01011074
## factor(Race)1 -0.18083917  0.48938939
## factor(Race)2 -0.23592831  0.41506339
## factor(Race)3 -0.08721198  0.63036601
## factor(Race)4 -0.13559561  0.60861316
## Speed          0.17562073  0.63299704
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: kneeMrange ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ochb
## 
## REML criterion at convergence: -313.7
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -2.6606 -0.4766 -0.0319  0.4868  4.9085 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.055950 0.23654 
##  Residual             0.009654 0.09826 
## Number of obs: 253, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)     0.776894   0.871444  20.617410   0.892   0.3829    
## factor(BS)1    -0.149490   0.144099  21.328240  -1.037   0.3112    
## factor(BS)2    -0.241206   0.111464  22.185824  -2.164   0.0415 *  
## age            -0.003854   0.011587  20.691317  -0.333   0.7427    
## leg_l          -0.005607   0.009788  22.492884  -0.573   0.5724    
## factor(Race)1   0.116251   0.171167  20.851652   0.679   0.5045    
## factor(Race)2   0.075698   0.166369  21.202099   0.455   0.6537    
## factor(Race)3   0.237526   0.183284  20.920454   1.296   0.2091    
## factor(Race)4   0.185624   0.190316  21.536860   0.975   0.3402    
## Speed           0.602181   0.126609 241.032361   4.756  3.4e-06 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.090                                                        
## factor(BS)2  0.016  0.474                                                 
## age         -0.229 -0.528 -0.100                                          
## leg_l       -0.917  0.136 -0.109 -0.076                                   
## factor(Rc)1 -0.139  0.341  0.144 -0.085  0.011                            
## factor(Rc)2 -0.098  0.164  0.101 -0.118  0.005  0.743                     
## factor(Rc)3 -0.124  0.250  0.102 -0.053  0.003  0.726  0.682              
## factor(Rc)4 -0.182 -0.016  0.045  0.190  0.022  0.628  0.619  0.584       
## Speed        0.032  0.131  0.205  0.014 -0.217 -0.081 -0.120 -0.079 -0.156
##            R2m       R2c
## [1,] 0.4020639 0.9120083
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.040128  2        1.195128
## age          1.645913  1        1.282931
## leg_l        1.128348  1        1.062237
## factor(Race) 1.525207  4        1.054183
## Speed        1.144184  1        1.069665
##                     2.5 %      97.5 %
## .sig01                 NA          NA
## .sigma                 NA          NA
## (Intercept)   -0.93110389  2.48489193
## factor(BS)1   -0.43191830  0.13293910
## factor(BS)2   -0.45967081 -0.02274171
## age           -0.02656364  0.01885519
## leg_l         -0.02479160  0.01357741
## factor(Race)1 -0.21922985  0.45173255
## factor(Race)2 -0.25037984  0.40177612
## factor(Race)3 -0.12170371  0.59675670
## factor(Race)4 -0.18738877  0.55863762
## Speed          0.35403203  0.85032981
## Residual analysis for Stiffness

## 
## 
## Residual analysis for Peak

## 
## 
## Residual analysis for InitialPeak

## 
## 
## Residual analysis for PeakMoment

## 
## 
## Residual analysis for kneeRange

## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Stiffness ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocmb
## 
## REML criterion at convergence: -1063.3
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -2.5518 -0.4703 -0.0899  0.3095  5.7021 
## 
## Random effects:
##  Groups   Name        Variance  Std.Dev.
##  Subject  (Intercept) 0.0010909 0.03303 
##  Residual             0.0004975 0.02230 
## Number of obs: 255, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)
## (Intercept)    -0.076914   0.123366  20.177355  -0.623    0.540
## factor(BS)1     0.019653   0.020414  20.832557   0.963    0.347
## factor(BS)2     0.002102   0.016242  23.133262   0.129    0.898
## age            -0.002499   0.001648  20.556769  -1.517    0.145
## leg_l           0.001852   0.001445  24.098449   1.281    0.212
## factor(Race)1   0.003720   0.024608  21.357058   0.151    0.881
## factor(Race)2   0.024487   0.024197  22.356228   1.012    0.322
## factor(Race)3   0.024488   0.026391  21.481218   0.928    0.364
## factor(Race)4  -0.002521   0.027474  22.113905  -0.092    0.928
## Speed           0.043781   0.030796 144.732930   1.422    0.157
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.090                                                        
## factor(BS)2  0.020  0.473                                                 
## age         -0.229 -0.520 -0.079                                          
## leg_l       -0.884  0.115 -0.169 -0.092                                   
## factor(Rc)1 -0.139  0.325  0.103 -0.093  0.052                            
## factor(Rc)2 -0.098  0.146  0.048 -0.130  0.063  0.750                     
## factor(Rc)3 -0.124  0.230  0.056 -0.060  0.050  0.734  0.694              
## factor(Rc)4 -0.182 -0.025  0.004  0.173  0.072  0.641  0.636  0.601       
## Speed        0.032  0.121  0.303  0.066 -0.353 -0.171 -0.239 -0.186 -0.237
##            R2m       R2c
## [1,] 0.1989545 0.7490954
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.143717  2        1.210018
## age          1.649766  1        1.284432
## leg_l        1.229303  1        1.108739
## factor(Race) 1.594393  4        1.060045
## Speed        1.360464  1        1.166389
##                       2.5 %      97.5 %
## .sig01                   NA          NA
## .sigma                   NA          NA
## (Intercept)   -0.3187078530 0.164879301
## factor(BS)1   -0.0203584733 0.059664791
## factor(BS)2   -0.0297317365 0.033935705
## age           -0.0057280385 0.000730059
## leg_l         -0.0009808461 0.004684377
## factor(Race)1 -0.0445116282 0.051951168
## factor(Race)2 -0.0229376117 0.071912268
## factor(Race)3 -0.0272380644 0.076214084
## factor(Race)4 -0.0563690250 0.051327923
## Speed         -0.0165780589 0.104140697
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Peak ~ factor(BS) + age + leg_l + factor(Race) + Speed + (1 |  
##     Subject)
##    Data: df_ocmb
## 
## REML criterion at convergence: 989.7
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.7277 -0.6065  0.0954  0.6488  2.5681 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 18.18    4.264   
##  Residual              1.89    1.375   
## Number of obs: 256, groups:  Subject, 30
## 
## Fixed effects:
##                Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)    16.06212   15.63131  20.59674   1.028  0.31607    
## factor(BS)1    -2.94769    2.56776  20.81084  -1.148  0.26401    
## factor(BS)2    -8.32595    1.98923  21.79323  -4.186  0.00039 ***
## age            -0.01286    0.20794  20.70372  -0.062  0.95126    
## leg_l          -0.04811    0.17510  22.27333  -0.275  0.78605    
## factor(Race)1   2.50345    3.07748  21.01623   0.813  0.42507    
## factor(Race)2  -2.25097    2.99286  21.41059  -0.752  0.46017    
## factor(Race)3   1.79382    3.29542  21.07785   0.544  0.59192    
## factor(Race)4  -0.11367    3.40553  21.34578  -0.033  0.97368    
## Speed           6.28376    2.17643 245.41041   2.887  0.00423 ** 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.092                                                        
## factor(BS)2  0.014  0.464                                                 
## age         -0.231 -0.529 -0.095                                          
## leg_l       -0.917  0.151 -0.103 -0.079                                   
## factor(Rc)1 -0.138  0.347  0.145 -0.088  0.013                            
## factor(Rc)2 -0.096  0.171  0.102 -0.121  0.006  0.743                     
## factor(Rc)3 -0.122  0.253  0.099 -0.053  0.007  0.727  0.684              
## factor(Rc)4 -0.181 -0.005  0.055  0.188  0.016  0.630  0.620  0.587       
## Speed        0.019  0.067  0.174  0.038 -0.207 -0.096 -0.136 -0.105 -0.135
##           R2m       R2c
## [1,] 0.496924 0.9526259
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.012205  2        1.191017
## age          1.646150  1        1.283024
## leg_l        1.123332  1        1.059874
## factor(Race) 1.519289  4        1.053671
## Speed        1.112332  1        1.054672
##                     2.5 %     97.5 %
## .sig01                 NA         NA
## .sigma                 NA         NA
## (Intercept)   -14.5746827 46.6989155
## factor(BS)1    -7.9804021  2.0850201
## factor(BS)2   -12.2247631 -4.4271340
## age            -0.4204126  0.3946839
## leg_l          -0.3912876  0.2950753
## factor(Race)1  -3.5283082  8.5352032
## factor(Race)2  -8.1168569  3.6149245
## factor(Race)3  -4.6650923  8.2527285
## factor(Race)4  -6.7883930  6.5610472
## Speed           2.0180414 10.5494859
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: InitialPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocmb
## 
## REML criterion at convergence: 1084.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -2.5972 -0.5670  0.0362  0.5327  2.5230 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 14.947   3.866   
##  Residual              2.934   1.713   
## Number of obs: 256, groups:  Subject, 30
## 
## Fixed effects:
##               Estimate Std. Error       df t value Pr(>|t|)  
## (Intercept)    22.2678    14.2436  20.8356   1.563   0.1330  
## factor(BS)1    -3.0655     2.3447  21.1962  -1.307   0.2051  
## factor(BS)2    -3.8673     1.8328  22.7666  -2.110   0.0461 *
## age             0.1466     0.1897  21.0254   0.773   0.4483  
## leg_l          -0.2042     0.1620  23.5217  -1.261   0.2198  
## factor(Race)1   0.1840     2.8157  21.5365   0.065   0.9485  
## factor(Race)2  -1.6826     2.7483  22.1815  -0.612   0.5466  
## factor(Race)3   0.4781     3.0168  21.6333   0.158   0.8755  
## factor(Race)4   3.0568     3.1253  22.0625   0.978   0.3386  
## Speed           3.1960     2.6028 225.2509   1.228   0.2208  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.091                                                        
## factor(BS)2  0.016  0.467                                                 
## age         -0.231 -0.526 -0.089                                          
## leg_l       -0.905  0.138 -0.126 -0.083                                   
## factor(Rc)1 -0.138  0.340  0.131 -0.090  0.026                            
## factor(Rc)2 -0.097  0.162  0.083 -0.124  0.026  0.746                     
## factor(Rc)3 -0.123  0.245  0.084 -0.056  0.021  0.729  0.687              
## factor(Rc)4 -0.181 -0.011  0.038  0.183  0.035  0.633  0.625  0.592       
## Speed        0.024  0.088  0.226  0.049 -0.267 -0.126 -0.178 -0.138 -0.176
##            R2m       R2c
## [1,] 0.2577701 0.8781971
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.055292  2        1.197342
## age          1.647285  1        1.283466
## leg_l        1.158086  1        1.076144
## factor(Race) 1.544345  4        1.055828
## Speed        1.193374  1        1.092416
##                    2.5 %     97.5 %
## .sig01                NA         NA
## .sigma                NA         NA
## (Intercept)   -5.6490401 50.1847077
## factor(BS)1   -7.6610421  1.5301358
## factor(BS)2   -7.4594955 -0.2751288
## age           -0.2251896  0.5183505
## leg_l         -0.5216693  0.1132972
## factor(Race)1 -5.3347031  5.7027227
## factor(Race)2 -7.0692333  3.7040013
## factor(Race)3 -5.4347929  6.3910031
## factor(Race)4 -3.0687366  9.1823002
## Speed         -1.9053838  8.2974431
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: MomentPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocmb
## 
## REML criterion at convergence: -402.1
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.3575 -0.4845 -0.0198  0.5388  3.0980 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.063481 0.25195 
##  Residual             0.006541 0.08088 
## Number of obs: 255, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)  
## (Intercept)     0.802525   0.923578  20.125927   0.869   0.3951  
## factor(BS)1    -0.162758   0.151732  20.344325  -1.073   0.2960  
## factor(BS)2    -0.291152   0.117540  21.304140  -2.477   0.0217 *
## age            -0.002277   0.012286  20.232908  -0.185   0.8548  
## leg_l          -0.003386   0.010344  21.755496  -0.327   0.7465  
## factor(Race)1   0.163252   0.181830  20.535480   0.898   0.3797  
## factor(Race)2   0.035068   0.176817  20.916149   0.198   0.8447  
## factor(Race)3   0.295881   0.194699  20.592677   1.520   0.1438  
## factor(Race)4   0.283771   0.201200  20.853826   1.410   0.1732  
## Speed           0.225882   0.128133 244.496234   1.763   0.0792 .
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.092                                                        
## factor(BS)2  0.014  0.465                                                 
## age         -0.231 -0.529 -0.095                                          
## leg_l       -0.917  0.151 -0.103 -0.079                                   
## factor(Rc)1 -0.138  0.347  0.145 -0.087  0.013                            
## factor(Rc)2 -0.096  0.171  0.102 -0.121  0.006  0.743                     
## factor(Rc)3 -0.122  0.253  0.099 -0.053  0.006  0.727  0.684              
## factor(Rc)4 -0.181 -0.004  0.055  0.188  0.016  0.629  0.620  0.587       
## Speed        0.018  0.068  0.174  0.037 -0.206 -0.096 -0.136 -0.105 -0.134
##            R2m      R2c
## [1,] 0.3445915 0.938773
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.011984  2        1.190985
## age          1.646282  1        1.283075
## leg_l        1.122923  1        1.059681
## factor(Race) 1.518792  4        1.053628
## Speed        1.111583  1        1.054316
##                     2.5 %      97.5 %
## .sig01                 NA          NA
## .sigma                 NA          NA
## (Intercept)   -1.00765349  2.61270393
## factor(BS)1   -0.46014845  0.13463173
## factor(BS)2   -0.52152743 -0.06077726
## age           -0.02635810  0.02180326
## leg_l         -0.02365921  0.01688744
## factor(Race)1 -0.19312798  0.51963111
## factor(Race)2 -0.31148552  0.38162246
## factor(Race)3 -0.08572143  0.67748267
## factor(Race)4 -0.11057377  0.67811584
## Speed         -0.02525464  0.47701894
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: kneeMrange ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ocmb
## 
## REML criterion at convergence: -371.1
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.7381 -0.5278 -0.0364  0.5639  2.8682 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.059798 0.24454 
##  Residual             0.007549 0.08689 
## Number of obs: 255, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)   
## (Intercept)     0.341305   0.897523  19.986719   0.380  0.70775   
## factor(BS)1    -0.161016   0.147538  20.244209  -1.091  0.28794   
## factor(BS)2    -0.298530   0.114572  21.360933  -2.606  0.01637 * 
## age            -0.000621   0.011943  20.114474  -0.052  0.95905   
## leg_l           0.000766   0.010094  21.883651   0.076  0.94019   
## factor(Race)1   0.118978   0.176893  20.468200   0.673  0.50872   
## factor(Race)2   0.023727   0.172185  20.913391   0.138  0.89172   
## factor(Race)3   0.257380   0.189441  20.534320   1.359  0.18900   
## factor(Race)4   0.213126   0.195898  20.838261   1.088  0.28904   
## Speed           0.437096   0.136185 241.755775   3.210  0.00151 **
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.092                                                        
## factor(BS)2  0.015  0.465                                                 
## age         -0.231 -0.529 -0.094                                          
## leg_l       -0.914  0.148 -0.109 -0.080                                   
## factor(Rc)1 -0.138  0.345  0.141 -0.088  0.016                            
## factor(Rc)2 -0.096  0.168  0.097 -0.122  0.011  0.744                     
## factor(Rc)3 -0.122  0.251  0.095 -0.054  0.010  0.728  0.685              
## factor(Rc)4 -0.181 -0.006  0.050  0.187  0.021  0.630  0.621  0.588       
## Speed        0.020  0.074  0.190  0.041 -0.224 -0.105 -0.148 -0.114 -0.147
##            R2m       R2c
## [1,] 0.3814397 0.9306615
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.023672  2        1.192710
## age          1.646630  1        1.283211
## leg_l        1.132286  1        1.064089
## factor(Race) 1.525510  4        1.054209
## Speed        1.133453  1        1.064638
##                     2.5 %      97.5 %
## .sig01                 NA          NA
## .sigma                 NA          NA
## (Intercept)   -1.41780792  2.10041847
## factor(BS)1   -0.45018600  0.12815449
## factor(BS)2   -0.52308671 -0.07397324
## age           -0.02402913  0.02278719
## leg_l         -0.01901683  0.02054889
## factor(Race)1 -0.22772569  0.46568201
## factor(Race)2 -0.31374915  0.36120245
## factor(Race)3 -0.11391631  0.62867694
## factor(Race)4 -0.17082658  0.59707918
## Speed          0.17017730  0.70401424
## Residual analysis for Stiffness

## 
## 
## Residual analysis for Peak

## 
## 
## Residual analysis for InitialPeak

## 
## 
## Residual analysis for PeakMoment

## 
## 
## Residual analysis for kneeRange

## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Stiffness ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ff
## 
## REML criterion at convergence: -1077
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -5.3581 -0.3891 -0.0303  0.3658  5.2558 
## 
## Random effects:
##  Groups   Name        Variance  Std.Dev.
##  Subject  (Intercept) 0.0008831 0.02972 
##  Residual             0.0002859 0.01691 
## Number of obs: 233, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)   -1.022e-01  1.120e-01  2.193e+01  -0.913 0.371254    
## factor(BS)1   -9.017e-03  1.814e-02  2.106e+01  -0.497 0.624211    
## factor(BS)2    6.537e-03  1.409e-02  2.227e+01   0.464 0.647284    
## age            4.599e-04  1.470e-03  2.102e+01   0.313 0.757482    
## leg_l          8.704e-04  1.219e-03  2.138e+01   0.714 0.482792    
## factor(Race)1  2.208e-02  2.179e-02  2.147e+01   1.013 0.322234    
## factor(Race)2  1.270e-02  2.112e-02  2.161e+01   0.601 0.554070    
## factor(Race)3  9.654e-03  2.332e-02  2.148e+01   0.414 0.682993    
## factor(Race)4  1.218e-03  2.434e-02  2.252e+01   0.050 0.960522    
## Speed          5.906e-02  1.659e-02  2.221e+02   3.559 0.000455 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.100                                                        
## factor(BS)2 -0.018  0.460                                                 
## age         -0.232 -0.533 -0.099                                          
## leg_l       -0.901  0.165 -0.086 -0.075                                   
## factor(Rc)1 -0.122  0.348  0.143 -0.083  0.003                            
## factor(Rc)2 -0.078  0.176  0.106 -0.117 -0.010  0.744                     
## factor(Rc)3 -0.106  0.255  0.099 -0.050 -0.005  0.728  0.684              
## factor(Rc)4 -0.148 -0.003  0.044  0.189  0.008  0.630  0.620  0.588       
## Speed       -0.155  0.041  0.185  0.021 -0.102 -0.092 -0.108 -0.095 -0.184
##            R2m       R2c
## [1,] 0.1642074 0.7955816
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.024033  2        1.192764
## age          1.647461  1        1.283534
## leg_l        1.087239  1        1.042708
## factor(Race) 1.534826  4        1.055012
## Speed        1.091415  1        1.044708
##                      2.5 %      97.5 %
## .sig01                  NA          NA
## .sigma                  NA          NA
## (Intercept)   -0.321709695 0.117262030
## factor(BS)1   -0.044564965 0.026530264
## factor(BS)2   -0.021087149 0.034161339
## age           -0.002421200 0.003340937
## leg_l         -0.001518024 0.003258844
## factor(Race)1 -0.020630205 0.064789049
## factor(Race)2 -0.028704116 0.054094989
## factor(Race)3 -0.036050949 0.055358272
## factor(Race)4 -0.046484019 0.048920388
## Speed          0.026534330 0.091585077
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Peak ~ factor(BS) + age + leg_l + factor(Race) + Speed + (1 |  
##     Subject)
##    Data: df_ff
## 
## REML criterion at convergence: 1003.9
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -2.6455 -0.5885 -0.0515  0.5158  3.2445 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 29.206   5.404   
##  Residual              2.896   1.702   
## Number of obs: 233, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)   
## (Intercept)    16.609077  19.910746  20.971078   0.834  0.41358   
## factor(BS)1    -2.440743   3.248935  20.657541  -0.751  0.46098   
## factor(BS)2    -8.870354   2.498627  21.102437  -3.550  0.00188 **
## age            -0.002559   0.263421  20.641086  -0.010  0.99234   
## leg_l           0.029956   0.217690  20.772969   0.138  0.89187   
## factor(Race)1   3.191576   3.890137  20.796418   0.820  0.42128   
## factor(Race)2  -1.869161   3.766243  20.847201  -0.496  0.62488   
## factor(Race)3   2.320141   4.162467  20.801381   0.557  0.58321   
## factor(Race)4   4.588738   4.306483  21.178056   1.066  0.29863   
## Speed           2.667695   1.737896 214.948721   1.535  0.12625   
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.096                                                        
## factor(BS)2  0.001  0.460                                                 
## age         -0.232 -0.533 -0.102                                          
## leg_l       -0.922  0.167 -0.075 -0.073                                   
## factor(Rc)1 -0.132  0.354  0.157 -0.084 -0.003                            
## factor(Rc)2 -0.088  0.180  0.121 -0.117 -0.018  0.742                     
## factor(Rc)3 -0.116  0.260  0.112 -0.050 -0.012  0.725  0.681              
## factor(Rc)4 -0.169  0.002  0.067  0.193 -0.004  0.627  0.615  0.583       
## Speed       -0.091  0.024  0.110  0.012 -0.060 -0.054 -0.063 -0.056 -0.109
##           R2m       R2c
## [1,] 0.405887 0.9463985
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   1.976834  2        1.185748
## age          1.645400  1        1.282732
## leg_l        1.079248  1        1.038869
## factor(Race) 1.501778  4        1.052145
## Speed        1.031311  1        1.015535
##                     2.5 %     97.5 %
## .sig01                 NA         NA
## .sigma                 NA         NA
## (Intercept)   -22.4152686 55.6334223
## factor(BS)1    -8.8085380  3.9270524
## factor(BS)2   -13.7675732 -3.9731353
## age            -0.5188539  0.5137368
## leg_l          -0.3967094  0.4566216
## factor(Race)1  -4.4329528 10.8161058
## factor(Race)2  -9.2508630  5.5125402
## factor(Race)3  -5.8381445 10.4784262
## factor(Race)4  -3.8518134 13.0292897
## Speed          -0.7385181  6.0739091
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: InitialPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ff
## 
## REML criterion at convergence: 997.3
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -2.34604 -0.58005 -0.00842  0.60925  2.60915 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 13.450   3.667   
##  Residual              3.032   1.741   
## Number of obs: 233, groups:  Subject, 30
## 
## Fixed effects:
##                Estimate Std. Error        df t value Pr(>|t|)  
## (Intercept)    24.20954   13.68787  21.41645   1.769   0.0912 .
## factor(BS)1    -2.45341    2.22368  20.76922  -1.103   0.2825  
## factor(BS)2    -4.00556    1.72074  21.67485  -2.328   0.0297 *
## age             0.23296    0.18025  20.73714   1.292   0.2104  
## leg_l          -0.16688    0.14924  21.00575  -1.118   0.2761  
## factor(Race)1   0.45634    2.66788  21.06415   0.171   0.8658  
## factor(Race)2  -1.86519    2.58476  21.16921  -0.722   0.4784  
## factor(Race)3   1.34890    2.85483  21.07367   0.472   0.6414  
## factor(Race)4   4.11304    2.96900  21.84926   1.385   0.1799  
## Speed          -0.06028    1.73782 222.59319  -0.035   0.9724  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.098                                                        
## factor(BS)2 -0.011  0.460                                                 
## age         -0.232 -0.533 -0.100                                          
## leg_l       -0.910  0.166 -0.082 -0.074                                   
## factor(Rc)1 -0.126  0.350  0.149 -0.083  0.000                            
## factor(Rc)2 -0.082  0.177  0.112 -0.117 -0.013  0.743                     
## factor(Rc)3 -0.110  0.257  0.104 -0.050 -0.008  0.727  0.683              
## factor(Rc)4 -0.157 -0.001  0.053  0.191  0.003  0.629  0.618  0.586       
## Speed       -0.133  0.035  0.159  0.017 -0.087 -0.079 -0.092 -0.081 -0.158
##            R2m       R2c
## [1,] 0.2844185 0.8683504
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.004708  2        1.189906
## age          1.646585  1        1.283193
## leg_l        1.083947  1        1.041128
## factor(Race) 1.521333  4        1.053848
## Speed        1.066753  1        1.032837
##                    2.5 %     97.5 %
## .sig01                NA         NA
## .sigma                NA         NA
## (Intercept)   -2.6181938 51.0372782
## factor(BS)1   -6.8117495  1.9049353
## factor(BS)2   -7.3781598 -0.6329663
## age           -0.1203318  0.5862474
## leg_l         -0.4593814  0.1256243
## factor(Race)1 -4.7726004  5.6852827
## factor(Race)2 -6.9312152  3.2008402
## factor(Race)3 -4.2464667  6.9442767
## factor(Race)4 -1.7060832  9.9321715
## Speed         -3.4663409  3.3457743
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: MomentPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ff
## 
## REML criterion at convergence: -283.8
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -1.96545 -0.63923 -0.02816  0.61231  3.03251 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.048368 0.21993 
##  Residual             0.009588 0.09792 
## Number of obs: 233, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)     0.530190   0.818606  21.110129   0.648 0.524178    
## factor(BS)1    -0.103009   0.133108  20.534638  -0.774 0.447824    
## factor(BS)2    -0.285120   0.102873  21.342422  -2.772 0.011327 *  
## age             0.004643   0.010790  20.505744   0.430 0.671500    
## leg_l          -0.004340   0.008930  20.745255  -0.486 0.632111    
## factor(Race)1   0.245047   0.159631  20.795269   1.535 0.139838    
## factor(Race)2   0.028482   0.154635  20.888639   0.184 0.855640    
## factor(Race)3   0.327794   0.170815  20.803869   1.919 0.068808 .  
## factor(Race)4   0.403101   0.177458  21.493998   2.272 0.033496 *  
## Speed           0.388262   0.098193 221.782014   3.954 0.000103 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.098                                                        
## factor(BS)2 -0.008  0.460                                                 
## age         -0.232 -0.533 -0.100                                          
## leg_l       -0.912  0.166 -0.080 -0.074                                   
## factor(Rc)1 -0.127  0.351  0.151 -0.083 -0.001                            
## factor(Rc)2 -0.083  0.178  0.114 -0.117 -0.014  0.743                     
## factor(Rc)3 -0.111  0.258  0.106 -0.050 -0.008  0.727  0.682              
## factor(Rc)4 -0.159  0.000  0.056  0.191  0.002  0.628  0.617  0.585       
## Speed       -0.126  0.033  0.150  0.017 -0.083 -0.074 -0.087 -0.077 -0.149
##            R2m       R2c
## [1,] 0.4604656 0.9107384
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   1.999008  2        1.189060
## age          1.646336  1        1.283096
## leg_l        1.082982  1        1.040664
## factor(Race) 1.517343  4        1.053502
## Speed        1.059495  1        1.029318
##                      2.5 %      97.5 %
## .sig01                  NA          NA
## .sigma                  NA          NA
## (Intercept)   -1.074248158  2.13462760
## factor(BS)1   -0.363895938  0.15787822
## factor(BS)2   -0.486747402 -0.08349186
## age           -0.016506063  0.02579119
## leg_l         -0.021842637  0.01316364
## factor(Race)1 -0.067823660  0.55791749
## factor(Race)2 -0.274595992  0.33156073
## factor(Race)3 -0.006997252  0.66258518
## factor(Race)4  0.055289599  0.75091219
## Speed          0.195806455  0.58071709
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: kneeMrange ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_ff
## 
## REML criterion at convergence: -191.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.3346 -0.6056 -0.0013  0.6360  3.0438 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.02825  0.1681  
##  Residual             0.01590  0.1261  
## Number of obs: 233, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)     0.053594   0.647326  20.498944   0.083 0.934820    
## factor(BS)1    -0.167998   0.104171  19.311654  -1.613 0.123027    
## factor(BS)2    -0.350719   0.081652  20.903296  -4.295 0.000324 ***
## age             0.007012   0.008440  19.262651   0.831 0.416301    
## leg_l          -0.001753   0.007016  19.738941  -0.250 0.805327    
## factor(Race)1   0.157210   0.125550  19.894966   1.252 0.225027    
## factor(Race)2  -0.088044   0.121825  20.088523  -0.723 0.478189    
## factor(Race)3   0.241394   0.134365  19.909024   1.797 0.087596 .  
## factor(Race)4   0.252941   0.141265  21.312744   1.791 0.087584 .  
## Speed           0.739337   0.119245 204.934048   6.200 3.06e-09 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.104                                                        
## factor(BS)2 -0.035  0.459                                                 
## age         -0.232 -0.532 -0.097                                          
## leg_l       -0.883  0.164 -0.094 -0.076                                   
## factor(Rc)1 -0.113  0.343  0.131 -0.081  0.008                            
## factor(Rc)2 -0.069  0.172  0.093 -0.117 -0.003  0.747                     
## factor(Rc)3 -0.098  0.251  0.088 -0.050  0.001  0.730  0.687              
## factor(Rc)4 -0.131 -0.008  0.024  0.186  0.019  0.634  0.624  0.592       
## Speed       -0.193  0.051  0.229  0.026 -0.127 -0.115 -0.134 -0.119 -0.227
##            R2m       R2c
## [1,] 0.6188809 0.8627328
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.064034  2        1.198614
## age          1.649438  1        1.284305
## leg_l        1.094161  1        1.046022
## factor(Race) 1.562565  4        1.057377
## Speed        1.142736  1        1.068988
##                      2.5 %      97.5 %
## .sig01                  NA          NA
## .sigma                  NA          NA
## (Intercept)   -1.215141588  1.32232869
## factor(BS)1   -0.372168738  0.03617239
## factor(BS)2   -0.510754138 -0.19068368
## age           -0.009531064  0.02355446
## leg_l         -0.015503238  0.01199822
## factor(Race)1 -0.088862687  0.40328309
## factor(Race)2 -0.326816543  0.15072852
## factor(Race)3 -0.021956008  0.50474461
## factor(Race)4 -0.023934235  0.52981586
## Speed          0.505622085  0.97305208
## Residual analysis for Stiffness

## 
## 
## Residual analysis for Peak

## 
## 
## Residual analysis for InitialPeak

## 
## 
## Residual analysis for PeakMoment

## 
## 
## Residual analysis for kneeRange

## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Stiffness ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_prf
## 
## REML criterion at convergence: -1049.4
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -5.9823 -0.4093 -0.0156  0.3092  6.2498 
## 
## Random effects:
##  Groups   Name        Variance  Std.Dev.
##  Subject  (Intercept) 0.0010319 0.03212 
##  Residual             0.0003758 0.01938 
## Number of obs: 239, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)  
## (Intercept)    7.676e-02  1.200e-01  2.025e+01   0.640   0.5295  
## factor(BS)1    1.096e-02  1.972e-02  2.046e+01   0.556   0.5843  
## factor(BS)2   -9.234e-03  1.569e-02  2.289e+01  -0.588   0.5621  
## age           -2.711e-03  1.592e-03  2.016e+01  -1.703   0.1040  
## leg_l         -4.888e-05  1.380e-03  2.319e+01  -0.035   0.9720  
## factor(Race)1 -1.212e-02  2.396e-02  2.145e+01  -0.506   0.6181  
## factor(Race)2  2.036e-02  2.339e-02  2.200e+01   0.870   0.3934  
## factor(Race)3  5.015e-03  2.600e-02  2.233e+01   0.193   0.8488  
## factor(Race)4  1.430e-03  2.668e-02  2.208e+01   0.054   0.9577  
## Speed          5.294e-02  3.009e-02  1.639e+02   1.759   0.0804 .
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.091                                                        
## factor(BS)2  0.011  0.461                                                 
## age         -0.235 -0.534 -0.107                                          
## leg_l       -0.888  0.138 -0.152 -0.060                                   
## factor(Rc)1 -0.134  0.337  0.100 -0.078  0.053                            
## factor(Rc)2 -0.092  0.160  0.050 -0.108  0.053  0.752                     
## factor(Rc)3 -0.114  0.236  0.035 -0.044  0.062  0.736  0.699              
## factor(Rc)4 -0.175 -0.011  0.003  0.194  0.066  0.643  0.636  0.608       
## Speed       -0.003  0.064  0.287 -0.017 -0.306 -0.195 -0.239 -0.255 -0.248
##            R2m       R2c
## [1,] 0.2162569 0.7907845
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.144012  2        1.210060
## age          1.646752  1        1.283258
## leg_l        1.185985  1        1.089029
## factor(Race) 1.621027  4        1.062243
## Speed        1.296800  1        1.138771
##                      2.5 %       97.5 %
## .sig01                  NA           NA
## .sigma                  NA           NA
## (Intercept)   -0.158391608 0.3119164240
## factor(BS)1   -0.027684985 0.0496049250
## factor(BS)2   -0.039994984 0.0215269118
## age           -0.005831471 0.0004095251
## leg_l         -0.002752861 0.0026551101
## factor(Race)1 -0.059081881 0.0348385941
## factor(Race)2 -0.025480997 0.0661976409
## factor(Race)3 -0.045944448 0.0559751594
## factor(Race)4 -0.050863676 0.0537235861
## Speed         -0.006038418 0.1119262171
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: Peak ~ factor(BS) + age + leg_l + factor(Race) + Speed + (1 |  
##     Subject)
##    Data: df_prf
## 
## REML criterion at convergence: 975.1
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -3.1723 -0.5589 -0.0071  0.5172  3.0697 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 21.852   4.675   
##  Residual              2.167   1.472   
## Number of obs: 243, groups:  Subject, 30
## 
## Fixed effects:
##               Estimate Std. Error       df t value Pr(>|t|)    
## (Intercept)    14.2941    17.1531  20.9467   0.833  0.41407    
## factor(BS)1    -2.4423     2.8131  21.0352  -0.868  0.39510    
## factor(BS)2    -6.8299     2.1827  22.1515  -3.129  0.00485 ** 
## age            -0.0463     0.2278  20.9055  -0.203  0.84088    
## leg_l          -0.1614     0.1913  22.3100  -0.844  0.40776    
## factor(Race)1   0.6942     3.3822  21.4832   0.205  0.83931    
## factor(Race)2  -4.3834     3.2831  21.7360  -1.335  0.19564    
## factor(Race)3   0.4416     3.6376  21.8886   0.121  0.90449    
## factor(Race)4  -0.8768     3.7414  21.7901  -0.234  0.81690    
## Speed          16.1276     2.5425 232.9483   6.343 1.16e-09 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.093                                                        
## factor(BS)2  0.011  0.461                                                 
## age         -0.233 -0.534 -0.105                                          
## leg_l       -0.917  0.158 -0.100 -0.068                                   
## factor(Rc)1 -0.136  0.350  0.141 -0.083  0.015                            
## factor(Rc)2 -0.093  0.174  0.100 -0.114  0.005  0.745                     
## factor(Rc)3 -0.119  0.253  0.088 -0.048  0.013  0.729  0.686              
## factor(Rc)4 -0.178 -0.001  0.051  0.194  0.017  0.631  0.621  0.591       
## Speed       -0.001  0.039  0.175 -0.011 -0.187 -0.117 -0.143 -0.154 -0.149
##            R2m       R2c
## [1,] 0.4756612 0.9526852
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.019036  2        1.192027
## age          1.644668  1        1.282446
## leg_l        1.114104  1        1.055511
## factor(Race) 1.531999  4        1.054769
## Speed        1.104165  1        1.050792
##                     2.5 %     97.5 %
## .sig01                 NA         NA
## .sigma                 NA         NA
## (Intercept)   -19.3254846 47.9135904
## factor(BS)1    -7.9558321  3.0713237
## factor(BS)2   -11.1078715 -2.5518674
## age            -0.4927071  0.4001043
## leg_l          -0.5364305  0.2135587
## factor(Race)1  -5.9348834  7.3232935
## factor(Race)2 -10.8181117  2.0512493
## factor(Race)3  -6.6879739  7.5711271
## factor(Race)4  -8.2098079  6.4562110
## Speed          11.1444206 21.1107864
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: InitialPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_prf
## 
## REML criterion at convergence: 1031
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -2.84777 -0.50469 -0.03149  0.57533  2.72548 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 15.084   3.884   
##  Residual              2.922   1.709   
## Number of obs: 243, groups:  Subject, 30
## 
## Fixed effects:
##                Estimate Std. Error        df t value Pr(>|t|)    
## (Intercept)    19.12458   14.34150  21.08176   1.334 0.196594    
## factor(BS)1    -2.11913    2.35415  21.23335  -0.900 0.378128    
## factor(BS)2    -2.66646    1.84623  23.04294  -1.444 0.162121    
## age             0.09444    0.19034  21.00016   0.496 0.624928    
## leg_l          -0.23964    0.16207  23.30206  -1.479 0.152629    
## factor(Race)1  -1.55310    2.84300  21.96298  -0.546 0.590375    
## factor(Race)2  -4.07044    2.76635  22.37960  -1.471 0.155102    
## factor(Race)3  -0.25031    3.06948  22.62806  -0.082 0.935724    
## factor(Race)4   0.04007    3.15407  22.45740   0.013 0.989977    
## Speed          10.28814    2.83099 217.31943   3.634 0.000348 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.093                                                        
## factor(BS)2  0.012  0.461                                                 
## age         -0.234 -0.534 -0.106                                          
## leg_l       -0.904  0.149 -0.123 -0.065                                   
## factor(Rc)1 -0.135  0.344  0.123 -0.081  0.031                            
## factor(Rc)2 -0.093  0.168  0.079 -0.112  0.026  0.748                     
## factor(Rc)3 -0.117  0.246  0.066 -0.046  0.034  0.732  0.691              
## factor(Rc)4 -0.177 -0.005  0.030  0.194  0.038  0.636  0.627  0.598       
## Speed       -0.001  0.051  0.230 -0.014 -0.245 -0.155 -0.189 -0.203 -0.197
##            R2m      R2c
## [1,] 0.2644345 0.880645
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.070649  2        1.199573
## age          1.644863  1        1.282522
## leg_l        1.144150  1        1.069650
## factor(Race) 1.568934  4        1.057915
## Speed        1.184352  1        1.088279
##                    2.5 %     97.5 %
## .sig01                NA         NA
## .sigma                NA         NA
## (Intercept)   -8.9842473 47.2333975
## factor(BS)1   -6.7331865  2.4949253
## factor(BS)2   -6.2849994  0.9520696
## age           -0.2786194  0.4675022
## leg_l         -0.5572849  0.0780073
## factor(Race)1 -7.1252687  4.0190778
## factor(Race)2 -9.4923843  1.3515006
## factor(Race)3 -6.2663861  5.7657718
## factor(Race)4 -6.1418049  6.2219374
## Speed          4.7395046 15.8367717
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: MomentPeak ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_prf
## 
## REML criterion at convergence: -396.8
## 
## Scaled residuals: 
##     Min      1Q  Median      3Q     Max 
## -2.6371 -0.5458  0.0000  0.6401  3.5590 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.033274 0.18241 
##  Residual             0.006367 0.07979 
## Number of obs: 243, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)    8.455e-01  6.735e-01  2.047e+01   1.255   0.2235    
## factor(BS)1   -7.234e-02  1.105e-01  2.062e+01  -0.654   0.5201    
## factor(BS)2   -1.104e-01  8.668e-02  2.237e+01  -1.274   0.2157    
## age           -4.877e-04  8.938e-03  2.039e+01  -0.055   0.9570    
## leg_l         -1.572e-02  7.608e-03  2.262e+01  -2.065   0.0505 .  
## factor(Race)1 -6.390e-03  1.335e-01  2.132e+01  -0.048   0.9623    
## factor(Race)2 -1.592e-01  1.299e-01  2.173e+01  -1.226   0.2335    
## factor(Race)3  1.430e-01  1.441e-01  2.197e+01   0.992   0.3318    
## factor(Race)4  2.065e-01  1.481e-01  2.180e+01   1.395   0.1772    
## Speed          9.202e-01  1.323e-01  2.175e+02   6.956 4.05e-11 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.093                                                        
## factor(BS)2  0.012  0.461                                                 
## age         -0.234 -0.534 -0.106                                          
## leg_l       -0.905  0.150 -0.122 -0.065                                   
## factor(Rc)1 -0.135  0.344  0.124 -0.081  0.031                            
## factor(Rc)2 -0.093  0.168  0.079 -0.112  0.025  0.748                     
## factor(Rc)3 -0.117  0.246  0.066 -0.046  0.034  0.732  0.691              
## factor(Rc)4 -0.177 -0.005  0.031  0.194  0.038  0.636  0.627  0.598       
## Speed       -0.001  0.051  0.229 -0.014 -0.244 -0.154 -0.189 -0.202 -0.196
##            R2m       R2c
## [1,] 0.5129273 0.9217663
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.069490  2        1.199405
## age          1.644859  1        1.282520
## leg_l        1.143476  1        1.069334
## factor(Race) 1.568102  4        1.057844
## Speed        1.182552  1        1.087452
##                     2.5 %        97.5 %
## .sig01                 NA            NA
## .sigma                 NA            NA
## (Intercept)   -0.47447497  2.1654775784
## factor(BS)1   -0.28900772  0.1443306782
## factor(BS)2   -0.28031237  0.0594494043
## age           -0.01800669  0.0170312100
## leg_l         -0.03062725 -0.0008028644
## factor(Race)1 -0.26802522  0.2552451390
## factor(Race)2 -0.41374769  0.0953872570
## factor(Race)3 -0.13944571  0.4254623806
## factor(Race)4 -0.08371166  0.4967768306
## Speed          0.66089518  1.1794535641
## Linear mixed model fit by REML. t-tests use Satterthwaite's method [
## lmerModLmerTest]
## Formula: kneeMrange ~ factor(BS) + age + leg_l + factor(Race) + Speed +  
##     (1 | Subject)
##    Data: df_prf
## 
## REML criterion at convergence: -375.8
## 
## Scaled residuals: 
##      Min       1Q   Median       3Q      Max 
## -2.60807 -0.61281 -0.00528  0.60741  2.25768 
## 
## Random effects:
##  Groups   Name        Variance Std.Dev.
##  Subject  (Intercept) 0.025351 0.1592  
##  Residual             0.007208 0.0849  
## Number of obs: 243, groups:  Subject, 30
## 
## Fixed effects:
##                 Estimate Std. Error         df t value Pr(>|t|)    
## (Intercept)    4.997e-01  5.915e-01  2.092e+01   0.845   0.4077    
## factor(BS)1   -8.523e-02  9.716e-02  2.112e+01  -0.877   0.3902    
## factor(BS)2   -1.213e-01  7.683e-02  2.334e+01  -1.579   0.1279    
## age            1.065e-04  7.846e-03  2.080e+01   0.014   0.9893    
## leg_l         -1.404e-02  6.752e-03  2.366e+01  -2.079   0.0486 *  
## factor(Race)1 -1.042e-01  1.177e-01  2.202e+01  -0.885   0.3859    
## factor(Race)2 -2.138e-01  1.148e-01  2.254e+01  -1.862   0.0757 .  
## factor(Race)3  5.007e-02  1.275e-01  2.285e+01   0.393   0.6982    
## factor(Race)4  6.781e-02  1.309e-01  2.262e+01   0.518   0.6095    
## Speed          1.257e+00  1.356e-01  1.904e+02   9.271   <2e-16 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Correlation of Fixed Effects:
##             (Intr) f(BS)1 f(BS)2 age    leg_l  fc(R)1 fc(R)2 fc(R)3 fc(R)4
## factor(BS)1 -0.092                                                        
## factor(BS)2  0.012  0.462                                                 
## age         -0.234 -0.534 -0.107                                          
## leg_l       -0.895  0.143 -0.140 -0.062                                   
## factor(Rc)1 -0.134  0.340  0.110 -0.080  0.043                            
## factor(Rc)2 -0.092  0.164  0.062 -0.110  0.041  0.750                     
## factor(Rc)3 -0.115  0.240  0.048 -0.045  0.050  0.735  0.695              
## factor(Rc)4 -0.176 -0.008  0.014  0.194  0.054  0.640  0.633  0.604       
## Speed       -0.002  0.059  0.264 -0.016 -0.282 -0.179 -0.219 -0.234 -0.228
##            R2m       R2c
## [1,] 0.6022749 0.9119508
##                  GVIF Df GVIF^(1/(2*Df))
## factor(BS)   2.111867  2        1.205498
## age          1.645019  1        1.282583
## leg_l        1.168124  1        1.080798
## factor(Race) 1.598579  4        1.060393
## Speed        1.248252  1        1.117252
##                     2.5 %        97.5 %
## .sig01                 NA            NA
## .sigma                 NA            NA
## (Intercept)   -0.65952266  1.6589290757
## factor(BS)1   -0.27566316  0.1052011176
## factor(BS)2   -0.27186703  0.0293005936
## age           -0.01527200  0.0154849460
## leg_l         -0.02727009 -0.0008035685
## factor(Race)1 -0.33493075  0.1266217883
## factor(Race)2 -0.43874392  0.0112234364
## factor(Race)3 -0.19984354  0.2999831636
## factor(Race)4 -0.18879207  0.3244087740
## Speed          0.99155029  1.5231605147
## Residual analysis for Stiffness

## 
## 
## Residual analysis for Peak

## 
## 
## Residual analysis for InitialPeak

## 
## 
## Residual analysis for PeakMoment

## 
## 
## Residual analysis for kneeRange