Date of Award
Master of Science (MS)
Nutrition and Food Sciences
The purpose of this study was to investigate the effect of a hypocaloric diet on the serum HDL levels and body composition of endurance athletes. Sixteen male athletes, 20 - 45 years of age, volunteered to run 10 miles daily during this 18 day study. For the first 7 days of the study, the subjects consumed a baseline diet and a supplement (muffin) to maintain body weight. The experimental period included a hypocaloric diet which the runner consumed from days 8 - 18. Phlebotomy occurred on days 1, 8, 10, 12, 15, and 18. The blood samples were analyzed for serum HDL, HDL-2, HDL-3, and APO A-I levels. Changes in body composition were determined prior to and after the hypocaloric period. Percent body fat was determined by skinfold thickness, and from this measurement lean body weight was calculated. Serum CPK, BUN, UUN, and urinary creatinine were used to indicate changes in lean muscle mass.
A significant loss of body weight, lean body weight, and percent body fat resulted from caloric restriction and exercise. Total HDL and HDL-2 increased significantly with weight loss and were determined to be predictive of one another. CPK levels increased and were significantly related to weight loss. BUN and UUN levels decreased and were not significantly correlated with a change in body weight or HDL.
The findings of this study indicate that in endurance athletes, HDL levels are elevated with exercise and are further elevated if exercise is accompanied by weight loss. As a result .of exercise and caloric restriction, percent body fat also decreased. Lean body weight decreased as a result of a loss of lean muscle mass and possibly other components of lean body tissue. The change in body composition of these male athletes suggests a possible mechanism for the increase in HDL levels.
Alina, Ellen Carol, "The Effect of a Hypocaloric Diet on the Body Weight, Body Composition and Serum HDL Levels of Male Endurance Athletes" (1983). Open Access Master's Theses. Paper 1030.