EFFECTS OF EXERCISE CESSATION ON LIPIDS AND LIPOPROTEINS IN DISTANCE RUNNERS AND POWER ATHLETES

The purpose of this study was to determine the effects of short-term e xercise cessation on lipid and lipoprotein profile and insulin sensiti vity in highly trained runners (n=12; mean age 19.9 years) and power a thletes (n=12; mean age 24.4 years). Following 14 days of exercise ces sation, running time to exhaustion and maximal oxygen uptake decreased by 9.2% and 4.8% (P<0.05) in the runners, while in the power athletes one repetition maximum squat and bench press did not change (P>0.05). No changes occurred in body composition. Data from a 2-h oral glucose tolerance test revealed an impairment of the glycemic state in all at hletes (P<0.05). In contrast, exercise cessation did not significantly (P>0.05) alter plasma levels of cholesterol, triglycerides, and low d ensity (LDL) and high density lipoprotein (HDL). No changes were obser ved in HDL2, HDL2b, and HDL3 subfractions, LDL diameter, and qualitati ve LDL pattern (P>0.05). These data thus suggest that despite a decrea se in insulin sensitivity, short-term exercise cessation, independent of exercise mode, was insufficient to alter plasma lipid and lipoprote in profiles in well-trained athletes.