Variable | Dehydrated mean±SD n=85 | Hydrated mean±SD n=233 |
Serum [Na+] (mmol/L) | 139.9±2.2 | 139.9±2.1 |
Serum [K+] (mmol/L) | 4.4±0.4 | 4.4±0.3 |
Serum osmolality (mOsmol/kgH2O) | 280.6±8.3 | 280.6±8.8 |
Urine osmolality (mOsmol/kgH2O) | 893.4±189.7 | 605.8±299.0*** |
Urine specific gravity | 1.022±0.003 | 1.011±0.004*** |
Thirst rating (0–10) | 4.3±1.8 | 4.4±1.8 |
By this definition, 27% of the athletes were dehydrated.
*P<0.05; **P<0.01; ***P<0.001 between dehydrated versus hydrated.
serum [K+], potassium concentration; serum [Na+], sodium concentration.