Markers of hydration status for entire cohort (n=318) and subdivided into females and males
| Variable | Combined mean±SD (min–max) | Females mean±SD n=193 | Males mean±SD n=125 | Normal range |
| Serum [Na+] (mmol/L) | 139.9±2.1 (134–145) | 139.7±2.0 | 140.1±2.2 | 135–145 |
| Serum [K+] (mmol/L) | 4.4±0.3 (3.6–6.4) | 4.4±0.3 | 4.4±0.4 | 3.5–5 |
| Serum osmolality (mOsmol/kgH2O) | 280.6±8.7 (261–307) | 280.8±8.9 | 280.2±8.3 | 275–295 |
| Urine osmolality (mOsmol/kgH2O) | 682.7±302 (110–1298) | 671.6±298.2 | 699.7±308.3 | 300–900 |
| Urine specific gravity | 1.014±0.006 (1.005–1.030) | 1.014±0.006 | 1.015±0.006* | 1.005–1.030 |
| Thirst rating (0–10) | 4.4±1.8 (0–10) | 4.5±1.8 | 4.2±1.9 |
*P<0.05 between females versus males.
The normal physiological range for each biochemical variable is listed in the last column.
serum [K+], potassium concentration; serum [Na+], sodium concentration.