
Fig.1
Body Mass and Total Body Composition. Changes between baseline and subsequent time points are displayed for body mass (A – B), fat mass (C – D), and lean body mass (E – F). Linear mixed model coefficients (b) and their 95% confidence intervals are displayed in panels A, C, and E. For all models, the reference groups were control (i.e., no water consumption) for condition and the baseline assessment for time. * indicates p ≤ 0.05; ** indicates p ≤ 0.01; *** indicates p ≤ 0.001.
Table 1
Participant characteristics. Data presented as mean ± SD.
| All (n=20) | Females (n=10) | Males (n=10) | |
|---|---|---|---|
| Age (y) | 22.2 ± 2.7 | 21.1 ± 1.6 | 23.2 ± 3.3 |
| Height (cm) | 172.9 ± 10.4 | 166.2 ± 6.1 | 179.6 ± 9.5 |
| Weight (kg) | 73.3 ± 20.4 | 59.0 ± 8.4 | 87.6 ± 18.8 |
| BMI (kg/m2) | 24.1 ± 4.3 | 21.3 ± 2.3 | 27.0 ± 4.1 |
| Body fat (%) | 21.8 ± 5.5 | 23.0 ± 4.0 | 20.5 ± 6.6 |

Fig.2
Raw Bioimpedance at 50 kHz. Changes between baseline and subsequent time points are displayed for right arm impedance at the 50 kHz measurement frequency (A – B), trunk impedance at the 50 kHz measurement frequency (C – D), right leg impedance at the 50 kHz measurement frequency (E – F), and whole body phase angle at the 50 kHz frequency (G – H). Linear mixed model coefficients (b) and their 95% confidence intervals are displayed in panels A, C, E, and G. For all models, the reference groups were control (i.e., no water consumption) for condition and the baseline assessment for time. * indicates p ≤ 0.05; ** indicates p ≤ 0.01; *** indicates p ≤ 0.001.

Fig.3
Body Fluids. Changes between baseline and subsequent time points are displayed for total body water (A – B), intracellular water (C – D), and extracellular water (E – F). Linear mixed model coefficients (b) and their 95% confidence intervals are displayed in panels A, C, and E. For all models, the reference groups were control (i.e., no water consumption) for condition and the baseline assessment for time. * indicates p ≤ 0.05; ** indicates p ≤ 0.01; *** indicates p ≤ 0.001.
| Condition | Time | Condition*Time | |
|---|---|---|---|
| Body mass | 0.0003 | <0.0001 | <0.0001 |
| Total body water | 0.06 | 0.0003 | 0.63 |
| Intracellular water | 0.08 | <0.0001 | 0.36 |
| Extracellular water | 0.06 | 0.26 | 0.90 |
| Dry lean mass | 0.24 | <0.0001 | 0.11 |
| Fat mass | <0.0001 | <0.0001 | <0.0001 |
| Lean body mass | 0.09 | 0.0001 | 0.45 |
| Skeletal muscle mass | 0.07 | <0.0001 | 0.42 |
| Body fat percentage | <0.0001 | <0.0001 | 0.0001 |
| Right arm lean body mass | 0.0003 | 0.002 | 0.49 |
| Left arm lean body mass | 0.02 | 0.01 | 0.54 |
| Trunk lean body mass | 0.01 | 0.002 | 0.55 |
| Right leg lean body mass | 0.76 | 0.0001 | 0.29 |
| Left leg lean body mass | 0.98 | <0.0001 | 0.86 |
| Right arm total body water | 0.0003 | 0.001 | 0.37 |
| Left arm total body water | 0.02 | 0.01 | 0.43 |
| Trunk total body water | 0.01 | 0.002 | 0.63 |
| Right leg total body water | 0.76 | <0.0001 | 0.18 |
| Left leg total body water | 0.95 | <0.0001 | 0.92 |
| Right arm intracellular water | 0.001 | 0.003 | 0.49 |
| Left arm intracellular water | 0.02 | 0.02 | 0.60 |
| Trunk intracellular water | 0.01 | <0.0001 | 0.72 |
| Right leg intracellular water | 0.91 | 0.54 | 0.04 |
| Left leg intracellular water | 0.95 | 0.11 | 0.28 |
| Right arm extracellular water | 0.0002 | 0.001 | 0.20 |
| Left arm extracellular water | 0.03 | 0.01 | 0.10 |
| Trunk extracellular water | 0.00 | 0.25 | 0.37 |
| Right leg extracellular water | 0.67 | <0.0001 | 0.19 |
| Left leg extracellular water | 0.87 | <0.0001 | 0.80 |
| Right arm fat mass | 0.00 | <0.0001 | 0.01 |
| Left arm fat mass | 0.00 | <0.0001 | 0.001 |
| Trunk fat mass | <0.0001 | <0.0001 | <0.0001 |
| Right leg fat mass | <0.0001 | <0.0001 | 0.0003 |
| Left leg fat mass | <0.0001 | <0.0001 | 0.04 |
| Visceral adipose tissue area | 0.0001 | <0.0001 | <0.0001 |
| Right arm Z at 1 kHz | 0.0002 | <0.0001 | <0.0001 |
| Left arm Z at 1 kHz | 0.001 | <0.0001 | <0.0001 |
| Trunk Z at 1 kHz | 0.50 | 0.22 | 0.08 |
| Right leg Z at 1 kHz | 0.24 | <0.0001 | 0.01 |
| Left leg Z at 1 kHz | 0.36 | <0.0001 | 0.08 |
| Right arm Z at 5 kHz | 0.00 | <0.0001 | <0.0001 |
| Left arm Z at 5 kHz | 0.00 | <0.0001 | <0.0001 |
| Trunk Z at 5 kHz | 0.34 | 0.09 | 0.12 |
| Right leg Z at 5 kHz | 0.25 | <0.0001 | 0.03 |
| Left leg Z at 5 kHz | 0.34 | <0.0001 | 0.02 |
| Right arm Z at 50 kHz | 0.0002 | 0.0002 | <0.0001 |
| Left arm Z at 50 kHz | 0.002 | 0.001 | 0.0001 |
| Trunk Z at 50 kHz | 0.24 | 0.16 | 0.12 |
| Right leg Z at 50 kHz | 0.25 | <0.0001 | 0.05 |
| Left leg Z at 50 kHz | 0.36 | <0.0001 | 0.01 |
| Right arm Z at 250 kHz | 0.0001 | 0.001 | 0.0004 |
| Left arm Z at 250 kHz | 0.001 | 0.0004 | 0.001 |
| Trunk Z at 250 kHz | 0.30 | 0.47 | 0.13 |
| Right leg Z at 250 kHz | 0.24 | <0.0001 | 0.08 |
| Left leg Z at 250 kHz | 0.33 | <0.0001 | 0.002 |
| Right arm Z at 500 kHz | 0.0001 | 0.0008 | 0.001 |
| Left arm Z at 500 kHz | 0.002 | 0.0001 | 0.002 |
| Trunk Z at 500 kHz | 0.22 | 0.67 | 0.11 |
| Right leg Z at 500 kHz | 0.22 | <0.0001 | 0.08 |
| Left leg Z at 500 kHz | 0.25 | <0.0001 | 0.001 |
| Right arm Z at 1000 kHz | 0.0001 | 0.001 | 0.001 |
| Left arm Z at 1000 kHz | 0.00 | <0.0001 | 0.01 |
| Trunk Z at 1000 kHz | 0.39 | 0.89 | 0.09 |
| Right leg Z at 1000 kHz | 0.18 | <0.0001 | 0.05 |
| Left leg Z at 1000 kHz | 0.33 | <0.0001 | 0.004 |
| Right arm Xc at 5 kHz | 0.0004 | <0.0001 | <0.0001 |
| Left arm Xc at 5 kHz | 0.001 | <0.0001 | 0.0002 |
| Trunk Xc at 5 kHz | 0.51 | 0.0004 | 0.21 |
| Right leg Xc at 5 kHz | 0.22 | <0.0001 | 0.05 |
| Left leg Xc at 5 kHz | 0.28 | <0.0001 | 0.29 |
| Right arm Xc at 50 kHz | 0.00 | <0.0001 | <0.0001 |
| Left arm Xc at 50 kHz | 0.01 | <0.0001 | 0.001 |
| Trunk Xc at 50 kHz | 0.77 | 0.03 | 0.18 |
| Right leg Xc at 50 kHz | 0.29 | <0.0001 | 0.01 |
| Left leg Xc at 50 kHz | 0.33 | <0.0001 | 0.01 |
| Right arm Xc at 250 kHz | 0.07 | 0.71 | 0.005 |
| Left arm Xc at 250 kHz | 0.001 | 0.02 | 0.0001 |
| Trunk Xc at 250 kHz | 0.30 | 0.46 | 0.14 |
| Right leg Xc at 250 kHz | 0.25 | <0.0001 | 0.01 |
| Left leg Xc at 250 kHz | 0.17 | <0.0001 | 0.01 |
| Right arm ϕ | 0.29 | 0.01 | 0.002 |
| Left arm ϕ | 0.45 | 0.002 | 0.17 |
| Trunk ϕ | 0.62 | 0.12 | 0.13 |
| Right leg ϕ | 0.41 | <0.0001 | 0.02 |
| Left leg ϕ | 0.41 | <0.0001 | 0.01 |
| Whole body ϕ | 0.33 | 0.01 | 0.0004 |
| Urine specific gravity | 0.03 | 0.004 | 0.0004 |