RESTORATION OF FLUID BALANCE AFTER EXERCISE-INDUCED DEHYDRATION - EFFECTS OF ALCOHOL-CONSUMPTION

The effect of alcohol consumption on the restoration of fluid and elec trolyte balance after exercise-induced dehydration [2.01 +/- 0.10% (SD ) of body mass] was investigated. Drinks containing 0, 1, 2, and 4% al cohol were consumed over 60 min beginning 30 min after the end of exer cise; a different beverage was consumed in each of four trials. The vo lume consumed (2,212 +/- 153 ml) was equivalent to 150% of body mass l oss. Peak urine flow rate occurred later (P = 0.024) with the 4% bever age. The total volume of urine produced over the 6 h after rehydration , although not different between trials (P = 0.307), tended to increas e as the quantity of alcohol ingested increased. The increase in blood (P = 0.013) and plasma (P = 0.050) volume with rehydration was slower when the 4% beverage was consumed and did not increase to values sign ificantly greater than the dehydrated level (P = 0.013 and P = 0.050 f or blood volume and plasma volume, respectively); generally, the incre ase was an inverse function of the quantity of alcohol consumed. These results suggest that alcohol has a negligible diuretic effect when co nsumed in dilute solution after a moderate level of hypohydration indu ced by exercise in the heat. There appears to be no difference in reco very from dehydration whether the rehydration beverage is alcohol free or contains up to 2% alcohol, but drinks containing 4% alcohol tend t o delay the recovery process.