Relationship of exercise, oral contraceptive use, and body fat to concentrations of plasma lipids and lipoprotein cholesterol in young women.

To investigate the relationship of exercise and oral contraceptive use to plasma lipids and lipoproteins, a cross-sectional study was designed to compare lipid levels in 96 exercising and non-exercising women who used or did not use oral contraceptives. Exercisers had significantly lower plasma triglyceride concentrations and low-density/high-density lipoprotein ratios than non-exercisers after adjustment for differences in pill type distribution between groups. Women using progestin-dominant pills had significantly lower plasma triglyceride and high-density lipoprotein concentrations and significantly higher low-density/high-density lipoprotein ratios compared with women using estrogen/progestin-balanced pills. As body fat was significantly associated with both pill type and physical activity, it is unclear how much of these lipoprotein differences were due to body fat, exercise, or pill use. Regular physical activity together with reduced body fat partially compensated for plasma lipoprotein differences associated with oral contraceptive use.