Correlations

Statistics within and between groups  
Call: statsBy(data = subset(df, select = c(opplev0, wbgt, tdist, tpace, 
    hit_distrun, veryhigh_distrun)), group = df$idg, cors = FALSE, 
    method = "pearson", use = "pairwise", alpha = 0.05)
Intraclass Correlation 1 (Percentage of variance due to groups) 
         opplev0             wbgt            tdist            tpace 
            0.66             0.96             0.07             0.12 
     hit_distrun veryhigh_distrun            group 
            0.13             0.40             1.00 
Intraclass Correlation 2 (Reliability of group differences) 
         opplev0             wbgt            tdist            tpace 
            0.95             0.99             0.39             0.55 
     hit_distrun veryhigh_distrun            group 
            0.56             0.86             1.00 
eta^2 between groups  
         opplev0.bg             wbgt.bg            tdist.bg            tpace.bg 
               0.69                0.96                0.17                0.22 
     hit_distrun.bg veryhigh_distrun.bg 
               0.22                0.46 
Correlation between groups 
                    opp0. wbgt. tdst. tpc.b ht_d. vry_.
opplev0.bg           1.00                              
wbgt.bg              0.18  1.00                        
tdist.bg             0.10 -0.37  1.00                  
tpace.bg             0.10 -0.48  0.86  1.00            
hit_distrun.bg       0.15 -0.14  0.58  0.51  1.00      
veryhigh_distrun.bg  0.11  0.03  0.11  0.11  0.82  1.00
Correlation within groups 
                    opp0. wbgt. tdst. tpc.w ht_d. vry_.
opplev0.wg           1.00                              
wbgt.wg              0.16  1.00                        
tdist.wg             0.07 -0.03  1.00                  
tpace.wg             0.02  0.04  0.64  1.00            
hit_distrun.wg       0.07 -0.02  0.74  0.63  1.00      
veryhigh_distrun.wg  0.09 -0.02  0.40  0.37  0.78  1.00

Many results are not shown directly. To see specific objects select from the following list:
 mean sd n F ICC1 ICC2 ci1 ci2 raw rbg ci.bg pbg rwg nw ci.wg pwg etabg etawg nwg nG Call
                    opp0. wbgt. tdst. tpc.b ht_d. vry_.
opplev0.bg          0.00                               
wbgt.bg             0.19  0.00                         
tdist.bg            0.48  0.01  0.00                   
tpace.bg            0.50  0.00  0.00  0.00             
hit_distrun.bg      0.28  0.31  0.00  0.00  0.00       
veryhigh_distrun.bg 0.42  0.84  0.42  0.45  0.00  0.00 
                    opp0. wbgt. tdst. tpc.w ht_d. vry_.
opplev0.wg          0.00                               
wbgt.wg             0.00  0.00                         
tdist.wg            0.11  0.55  0.00                   
tpace.wg            0.63  0.41  0.00  0.00             
hit_distrun.wg      0.15  0.64  0.00  0.00  0.00       
veryhigh_distrun.wg 0.06  0.69  0.00  0.00  0.00  0.00 


Regression Models


DV: Total distance

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: tdist ~ grand.cent.wbgt + opplev0 + pos + grand.cent.wbgt * pos +  
    (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   8384.9    8438.9   -4179.4    8358.9       457 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-3.7246 -0.4061  0.1499  0.5796  2.5631 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept)  207037   455    
 Residual             2936741  1714    
Number of obs: 470, groups:  idg, 52

Fixed effects:
                               Estimate Std. Error        df t value Pr(>|t|)
(Intercept)                    8470.795    226.399   278.806  37.415  < 2e-16
grand.cent.wbgt                   3.473     23.853   356.163   0.146 0.884318
opplev0                         209.267    113.244   151.276   1.848 0.066564
posforward                     -556.564    297.122   427.163  -1.873 0.061726
posmidfielder                   808.526    234.123   434.600   3.453 0.000608
poswide_midf                  -1306.937    267.808   432.678  -4.880 1.49e-06
poswing_back                    350.678    237.553   434.135   1.476 0.140612
grand.cent.wbgt:posforward      -32.851     37.882   427.969  -0.867 0.386327
grand.cent.wbgt:posmidfielder   -51.658     30.130   433.589  -1.714 0.087154
grand.cent.wbgt:poswide_midf    -99.392     34.503   436.308  -2.881 0.004164
grand.cent.wbgt:poswing_back    -53.281     29.842   433.263  -1.785 0.074894
                                 
(Intercept)                   ***
grand.cent.wbgt                  
opplev0                       .  
posforward                    .  
posmidfielder                 ***
poswide_midf                  ***
poswing_back                     
grand.cent.wbgt:posforward       
grand.cent.wbgt:posmidfielder .  
grand.cent.wbgt:poswide_midf  ** 
grand.cent.wbgt:poswing_back  .  
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
                    (Intr) grnd.. opplv0 psfrwr psmdfl pswd_m pswng_
grnd.cnt.wb          0.105                                          
opplev0             -0.552 -0.110                                   
posforward          -0.480 -0.033  0.019                            
posmidfildr         -0.611 -0.043  0.026  0.454                     
poswide_mdf         -0.543 -0.038  0.042  0.397  0.505              
poswing_bck         -0.596 -0.041  0.014  0.447  0.570  0.497       
grnd.cnt.wbgt:psf   -0.033 -0.557  0.014  0.017  0.025  0.022  0.024
grnd.cnt.wbgt:psm   -0.053 -0.698  0.039  0.025  0.009  0.028  0.031
grnd.cnt.wbgt:pswd_ -0.037 -0.608  0.017  0.022  0.027  0.081  0.027
grnd.cnt.wbgt:pswn_ -0.035 -0.701  0.006  0.024  0.031  0.027  0.014
                    grnd.cnt.wbgt:psf grnd.cnt.wbgt:psm grnd.cnt.wbgt:pswd_
grnd.cnt.wb                                                                
opplev0                                                                    
posforward                                                                 
posmidfildr                                                                
poswide_mdf                                                                
poswing_bck                                                                
grnd.cnt.wbgt:psf                                                          
grnd.cnt.wbgt:psm    0.435                                                 
grnd.cnt.wbgt:pswd_  0.378             0.483                               
grnd.cnt.wbgt:pswn_  0.440             0.557             0.487             


DV: Total pace

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: tpace ~ grand.cent.wbgt + opplev0 + (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   4072.8    4093.5   -2031.4    4062.8       465 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-4.2311 -0.4074  0.0955  0.6545  2.7495 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept)  23.77    4.875  
 Residual             313.89   17.717  
Number of obs: 470, groups:  idg, 52

Fixed effects:
                Estimate Std. Error       df t value Pr(>|t|)    
(Intercept)      99.8685     1.6424 100.2824  60.807  < 2e-16 ***
grand.cent.wbgt  -0.4803     0.1375  66.8954  -3.492 0.000855 ***
opplev0           1.5534     1.1781 164.6799   1.319 0.189148    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd..
grnd.cnt.wb  0.134       
opplev0     -0.760 -0.161


DV: Stand and Walk

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: stand_walk ~ grand.cent.wbgt + opplev0 + (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   7119.3    7140.1   -3554.7    7109.3       465 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-3.2159 -0.6878  0.1522  0.7271  2.6447 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept)   8053    89.74  
 Residual             210149   458.42  
Number of obs: 470, groups:  idg, 52

Fixed effects:
                Estimate Std. Error       df t value Pr(>|t|)    
(Intercept)     1677.938     38.943   93.928  43.087   <2e-16 ***
grand.cent.wbgt   -2.851      3.198   64.894  -0.892   0.3758    
opplev0           68.413     28.489  140.436   2.401   0.0176 *  
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd..
grnd.cnt.wb  0.135       
opplev0     -0.774 -0.164

 

DV: High Distance Running

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: hit_distrun ~ grand.cent.wbgt + opplev0 + (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   7354.6    7375.4   -3672.3    7344.6       465 

Scaled residuals: 
     Min       1Q   Median       3Q      Max 
-2.68454 -0.74244  0.03125  0.65197  3.15622 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept)  41519   203.8   
 Residual             329578   574.1   
Number of obs: 470, groups:  idg, 52

Fixed effects:
                Estimate Std. Error       df t value Pr(>|t|)    
(Intercept)     1677.538     58.177   95.847  28.835   <2e-16 ***
grand.cent.wbgt   -5.626      4.981   61.909  -1.130   0.2630    
opplev0           75.098     40.712  181.788   1.845   0.0667 .  
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd..
grnd.cnt.wb  0.131       
opplev0     -0.743 -0.158


DV: Very high Distance Run

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: veryhigh_distrun ~ grand.cent.wbgt + opplev0 + grand.cent.wbgt *  
    opplev0 + (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   6859.1    6884.0   -3423.5    6847.1       464 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-4.2793 -0.6508 -0.0322  0.5832  4.3169 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept)  63093   251.2   
 Residual             100974   317.8   
Number of obs: 470, groups:  idg, 52

Fixed effects:
                        Estimate Std. Error      df t value Pr(>|t|)    
(Intercept)              602.995     48.265 100.832  12.494   <2e-16 ***
grand.cent.wbgt           -4.199      6.067 192.332  -0.692   0.4897    
opplev0                   54.378     27.756 396.694   1.959   0.0508 .  
grand.cent.wbgt:opplev0    3.581      3.868 332.510   0.926   0.3553    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd.. opplv0
grnd.cnt.wb  0.141              
opplev0     -0.613 -0.111       
grnd.cnt.:0 -0.089 -0.675  0.003

 

DV: Thr < 80

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: thr_less_80 ~ grand.cent.wbgt + opplev0 + (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   3841.6    3862.4   -1915.8    3831.6       465 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-1.9493 -0.7845 -0.1305  0.6456  3.5969 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept)  10.47    3.235  
 Residual             194.61   13.950  
Number of obs: 470, groups:  idg, 52

Fixed effects:
                Estimate Std. Error       df t value Pr(>|t|)    
(Intercept)      24.0940     1.2323  78.9504  19.553  < 2e-16 ***
grand.cent.wbgt  -0.4056     0.1020  52.8270  -3.974 0.000215 ***
opplev0           0.7571     0.8940 126.1001   0.847 0.398712    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd..
grnd.cnt.wb  0.134       
opplev0     -0.769 -0.163


DV: Thr > 80

boundary (singular) fit: see help('isSingular')
Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: thr_over_80 ~ grand.cent.wbgt + opplev0 + (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   4058.8    4079.5   -2024.4    4048.8       465 

Scaled residuals: 
     Min       1Q   Median       3Q      Max 
-3.02990 -0.65020  0.08811  0.71160  2.27362 

Random effects:
 Groups   Name        Variance  Std.Dev. 
 idg      (Intercept) 5.920e-16 2.433e-08
 Residual             3.226e+02 1.796e+01
Number of obs: 470, groups:  idg, 52

Fixed effects:
                 Estimate Std. Error        df t value Pr(>|t|)    
(Intercept)      54.67647    1.34854 470.00000   40.55  < 2e-16 ***
grand.cent.wbgt   0.08539    0.10808 470.00000    0.79 0.429917    
opplev0           3.38762    1.00823 470.00000    3.36 0.000843 ***
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd..
grnd.cnt.wb  0.132       
opplev0     -0.789 -0.168
optimizer (bobyqa) convergence code: 0 (OK)
boundary (singular) fit: see help('isSingular')


DV: Sprints

boundary (singular) fit: see help('isSingular')
Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: sprints ~ grand.cent.wbgt + opplev0 + grand.cent.wbgt * opplev0 +  
    (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   3066.5    3091.4   -1527.2    3054.5       464 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-1.8759 -0.8397 -0.2059  0.6376  2.8907 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept)  0.0     0.000   
 Residual             38.9     6.237   
Number of obs: 470, groups:  idg, 52

Fixed effects:
                         Estimate Std. Error        df t value Pr(>|t|)    
(Intercept)              10.93843    0.46918 470.00000  23.314   <2e-16 ***
grand.cent.wbgt           0.04235    0.06457 470.00000   0.656    0.512    
opplev0                   0.38179    0.35062 470.00000   1.089    0.277    
grand.cent.wbgt:opplev0  -0.04002    0.04555 470.00000  -0.878    0.380    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd.. opplv0
grnd.cnt.wb  0.128              
opplev0     -0.783 -0.053       
grnd.cnt.:0 -0.063 -0.814 -0.054
optimizer (bobyqa) convergence code: 0 (OK)
boundary (singular) fit: see help('isSingular')


DV: Deccelaration hit

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: decel_hit ~ grand.cent.wbgt + opplev0 + grand.cent.wbgt * opplev0 +  
    (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   3963.7    3988.6   -1975.8    3951.7       464 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-2.9368 -0.6036 -0.1132  0.5090  3.6527 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept) 160.4    12.67   
 Residual             209.1    14.46   
Number of obs: 470, groups:  idg, 52

Fixed effects:
                        Estimate Std. Error       df t value Pr(>|t|)    
(Intercept)              34.1631     2.3401  92.4406  14.599  < 2e-16 ***
grand.cent.wbgt          -0.8971     0.2879 198.7958  -3.116  0.00211 ** 
opplev0                   3.7520     1.2889 420.4462   2.911  0.00379 ** 
grand.cent.wbgt:opplev0   0.1636     0.1807 359.9103   0.905  0.36590    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd.. opplv0
grnd.cnt.wb  0.137              
opplev0     -0.587 -0.115       
grnd.cnt.:0 -0.087 -0.654  0.006


DV: Acceleration hit

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: accel_hit ~ grand.cent.wbgt + opplev0 + (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   3941.0    3961.8   -1965.5    3931.0       465 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-3.8540 -0.4743 -0.1056  0.3634  3.5265 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept) 280.3    16.74   
 Residual             187.2    13.68   
Number of obs: 470, groups:  idg, 52

Fixed effects:
                Estimate Std. Error       df t value Pr(>|t|)    
(Intercept)      26.9460     2.7718  80.7073   9.722  3.1e-15 ***
grand.cent.wbgt  -0.8276     0.2538 125.3967  -3.261  0.00143 ** 
opplev0           4.2819     1.2838 467.8990   3.335  0.00092 ***
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd..
grnd.cnt.wb  0.092       
opplev0     -0.494 -0.146


Dv: Distance Zone 3

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: distzone3 ~ grand.cent.wbgt + opplev0 + grand.cent.wbgt * opplev0 +  
    (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   6955.1    6980.0   -3471.5    6943.1       464 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-2.3150 -0.7051 -0.1342  0.6042  3.9554 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept)   9464    97.28  
 Residual             144873   380.62  
Number of obs: 470, groups:  idg, 52

Fixed effects:
                         Estimate Std. Error        df t value Pr(>|t|)    
(Intercept)             1063.9974    34.6287   80.6146  30.726   <2e-16 ***
grand.cent.wbgt           -5.3762     4.7309   89.8009  -1.136    0.259    
opplev0                   25.8979    24.9043  135.0412   1.040    0.300    
grand.cent.wbgt:opplev0   -0.7761     3.2926  108.9282  -0.236    0.814    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd.. opplv0
grnd.cnt.wb  0.145              
opplev0     -0.759 -0.074       
grnd.cnt.:0 -0.080 -0.794 -0.031

 

DV: Distance Zone 4

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: distzone4 ~ grand.cent.wbgt + opplev0 + grand.cent.wbgt * opplev0 +  
    (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   6445.6    6470.5   -3216.8    6433.6       463 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-4.1183 -0.6423 -0.0195  0.5144  4.7247 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept) 25290    159.0   
 Residual             43402    208.3   
Number of obs: 469, groups:  idg, 52

Fixed effects:
                        Estimate Std. Error      df t value Pr(>|t|)    
(Intercept)              442.637     30.988 101.785  14.284   <2e-16 ***
grand.cent.wbgt           -2.693      3.920 187.691  -0.687   0.4930    
opplev0                   31.531     18.065 386.452   1.745   0.0817 .  
grand.cent.wbgt:opplev0    2.096      2.513 321.213   0.834   0.4049    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd.. opplv0
grnd.cnt.wb  0.142              
opplev0     -0.621 -0.110       
grnd.cnt.:0 -0.090 -0.682  0.002

 

Dv: Distance Zone 5

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: distzone5 ~ grand.cent.wbgt + opplev0 + grand.cent.wbgt * opplev0 +  
    (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   6051.6    6076.5   -3019.8    6039.6       464 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-3.4987 -0.6107 -0.2089  0.4658  5.8319 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept)  8311     91.16  
 Residual             18685    136.69  
Number of obs: 470, groups:  idg, 52

Fixed effects:
                        Estimate Std. Error       df t value Pr(>|t|)    
(Intercept)             161.6388    18.8064 104.2133   8.595 8.95e-14 ***
grand.cent.wbgt          -0.9496     2.4304 170.6504  -0.391   0.6965    
opplev0                  21.8546    11.4924 344.3103   1.902   0.0581 .  
grand.cent.wbgt:opplev0   1.1670     1.5862 277.9183   0.736   0.4625    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd.. opplv0
grnd.cnt.wb  0.146              
opplev0     -0.650 -0.105       
grnd.cnt.:0 -0.091 -0.706 -0.001


DV: Training Load

boundary (singular) fit: see help('isSingular')
Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: tload ~ grand.cent.wbgt + opplev0 + grand.cent.wbgt * opplev0 +  
    (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   5276.2    5301.1   -2632.1    5264.2       464 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-3.2915 -0.6351  0.0484  0.6534  2.3178 

Random effects:
 Groups   Name        Variance  Std.Dev. 
 idg      (Intercept) 6.082e-14 2.466e-07
 Residual             4.283e+03 6.545e+01
Number of obs: 470, groups:  idg, 52

Fixed effects:
                        Estimate Std. Error       df t value Pr(>|t|)    
(Intercept)             228.8387     4.9231 470.0000  46.482  < 2e-16 ***
grand.cent.wbgt           0.7990     0.6776 470.0000   1.179 0.238910    
opplev0                  13.1613     3.6790 470.0000   3.577 0.000383 ***
grand.cent.wbgt:opplev0  -0.5488     0.4780 470.0000  -1.148 0.251490    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd.. opplv0
grnd.cnt.wb  0.128              
opplev0     -0.783 -0.053       
grnd.cnt.:0 -0.063 -0.814 -0.054
optimizer (bobyqa) convergence code: 0 (OK)
boundary (singular) fit: see help('isSingular')


DV: Cardio Load

Linear mixed model fit by maximum likelihood . t-tests use Satterthwaite's
  method [lmerModLmerTest]
Formula: cload ~ grand.cent.wbgt + opplev0 + grand.cent.wbgt * opplev0 +  
    (1 | idg)
   Data: df
Control: lmerControl(optimizer = "bobyqa")

      AIC       BIC    logLik -2*log(L)  df.resid 
   5072.4    5097.3   -2530.2    5060.4       464 

Scaled residuals: 
    Min      1Q  Median      3Q     Max 
-3.2284 -0.5074  0.1248  0.7031  2.5012 

Random effects:
 Groups   Name        Variance Std.Dev.
 idg      (Intercept)    1.305  1.143  
 Residual             2775.191 52.680  
Number of obs: 470, groups:  idg, 52

Fixed effects:
                        Estimate Std. Error       df t value Pr(>|t|)    
(Intercept)             175.4663     3.9702  74.5172  44.196  < 2e-16 ***
grand.cent.wbgt           0.8382     0.5464  78.5689   1.534  0.12904    
opplev0                   8.6924     2.9660 105.6633   2.931  0.00415 ** 
grand.cent.wbgt:opplev0  -0.4064     0.3854  87.2580  -1.054  0.29458    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Correlation of Fixed Effects:
            (Intr) grnd.. opplv0
grnd.cnt.wb  0.128              
opplev0     -0.783 -0.053       
grnd.cnt.:0 -0.063 -0.814 -0.054