Variable
Hyponatremia Status
p-value2
0
N = 426
1
1
N = 62
1
Sex

<0.001
    Male 297 (70%) 25 (40%)
    Female 129 (30%) 37 (60%)
Previous Marathons 9.0 ± 11.9 7.7 ± 13.9 0.5
    Unknown 3 0
Age (years) 39.0 ± 9.4 38.1 ± 9.5 0.5
    Unknown 2 0
NSAID Use 222 (53%) 37 (61%) 0.3
    Unknown 10 1
Water Loading 304 (73%) 50 (82%) 0.2
    Unknown 11 1
Pre-Race Weight (kg) 69.7 ± 10.9 66.4 ± 14.5 0.10
    Unknown 17 2
Pre-Race Height (m) 1.7 ± 0.1 1.7 ± 0.1 0.007
    Unknown 18 0
Frequent Voiding

0.011
    <3 times 402 (95%) 51 (86%)
    ≥3 times 19 (4.5%) 8 (14%)
    Unknown 5 3
Fluid Frequency

<0.001
    Every mile 230 (54%) 46 (75%)
    Every other mile 153 (36%) 15 (25%)
    Every third mile 40 (9.5%) 0 (0%)
    Unknown 3 1
Post-Race Weight (kg) 68.7 ± 10.8 67.8 ± 14.4 0.6
    Unknown 15 5
Weight Change (kg) -0.9 ± 1.5 0.7 ± 1.4 <0.001
    Unknown 28 5
Race Time (min) 221.7 ± 39.4 252.2 ± 47.1 <0.001
    Unknown 9 2
Training Pace (sec/mile) 482.2 ± 61.2 531.6 ± 71.5 <0.001
    Unknown 54 5
BMI (kg/m²) 23.0 ± 2.5 22.8 ± 3.7 0.7
    Unknown 21 2
1 n (%); Mean ± SD
2 Fisher’s exact test; Welch Two Sample t-test