RELATIONSHIP BETWEEN PHYSICAL-ACTIVITY AND HDL-CHOLESTEROL IN HEALTHYOLDER MEN AND WOMEN - A CROSS-SECTIONAL AND EXERCISE INTERVENTION STUDY

We used cross sectional and exercise intervention studies to examine w hether physical activity levels or increases in peak aerobic capacity (peak VO2) explain variation in high density lipoprotein cholesterol ( HDL-C) levels in older men and women. In the cross-sectional study, 30 7 older individuals (169 men; 138 women; 67 +/- 7 years) were characte rized for HDL-C, leisure time physical activity, peak VO2, body compos ition, body fat distribution and dietary intake. HDL-C was 19% higher (P < 0.001) in women (57 +/- 14 mg/dl) versus men (48 +/- 14 mg/dl). T hirty-two percent of the variation in HDL-C in older men was explained by the waist circumference (r(2) = 16%): percent dietary intake of al cohol (r(2) = 11%), and carbohydrate (r(2) = 6%). Waist circumference was also the best predictor of HDL-C in older women, (r(2) = 7%); with percent dietary intake of carbohydrate adding an additional 6% to the model. Neither peak VO2 nor leisure time physical activity were indep endent predictors of HDL-C. Statistical control for the aforementioned variables diminished, but did not abolish gender differences in HDL-C . Thirty-seven older individuals (23 men; 14 women) participated in a 2-month exercise program in which individuals by week eight were expen ding approximately 900 kcal per week in exercise energy expenditure. S ubjects were maintained in energy balance throughout the exercise prog ram. Endurance training significantly increased peak VO2 by 15% in bot h men and women, and by design, body composition and body fat distribu tion did not change. No changes in HDL-C levels were noted. In conclus ion, variations in leisure time physical activity or increases in peak VO2 are not independent predictors of HDL-C levels in healthy older m en and women. Instead, central adiposity, as estimated by the waist ci rcumference, and to a lesser extent, dietary Intake of carbohydrate an d alcohol, are significant predictors of variation in plasma HDL-C lev els. Furthermore, short-term exercise training, generating less than 9 00 kcal per week in exercise energy expenditure, in the absence of wei ght loss, fails to influence HDL-C levels.