ALCOHOL-CONSUMPTION AND PHYSICAL-FITNESS AMONG YOUNG-ADULTS

The relationship between alcohol consumption and physical fitness was analyzed using data from the baseline examination of the Coronary Artery Disease Risk Development In Young Adults study (CARDIA), a longitudinal study of the evolution of risk factors for cardiovascular disease in Black and White men and women aged 18-30 years. Two parameters of submaximal exercise treadmill testing were evaluated: time to heart rate 130 and duration of the treadmill test. In men and women qualified for treadmill testing, time to reach heart rate 130 was positively associated with ethanol intake, The relationship between fitness and ethanol intake persisted in sex-specific analysis after adjustment for age, ethnicity, systolic blood pressure, sum of subscapular and triceps skinfolds, and physical activity level. The magnitude and strength of the relationship were greater in women than in men. A negative interaction between ethanol intake and smoking status was evident. Linear regression co-efficients in men were 0.29 sec to heart rate 130/ml ethanol/day in nonsmokers and -0.06 sec to heart rate 130/ml ethanol/day in smokers. Linear regression coefficients in women were 1.07 sec to heart rate 130/ml ethanol/day in nonsmokers and 0.23 sec to heart rate 130/ml ethanol/day in smokers. Men and women who smoked showed 31 sec longer time to heart rate 130, regardless of ethanol intake, Mean daily ethanol intake was positively associated with duration of treadmill testing in women, but weakly associated with duration in men, These results show increased physical fitness as ethanol intake increased in women and nonsmoking men and mildly decreased physical fitness as ethanol consumption increases among men who smoke. The positive association of physical activity with ethanol intake among nonsmokers combined with downregulation of beta-adrenergic receptors in smokers may partially explain these results. Physical activity levels increase as ethanol consumption increases in nonsmokers, whereas smokers have a constant physical activity level. This alcohol-fitness relationship may change as physical activity levels decline with age or as the association of ethanol with physical activity changes.