Lipid and lipoprotein levels were prospectively studied in previously sedentary men (mean age, 33 years) and women (mean age, 27 years) undergoing 16 weeks of weight-training exercise. Women demonstrated a 9.5% reduction of cholesterol, 17.9% decrease in low-density lipoprotein (LDL) cholesterol and 28.3% lowering of triglycerides. The ratios of total cholesterol-high-density lipoprotein (HDL) cholesterol and LDL cholesterol-HDL cholesterol were reduced 14.3% and 20.3%, respectively. Among men, LDL cholesterol was reduced 16.2%, while the ratios of total cholesterol-HDL cholesterol and LDL cholesterol-HDL cholesterol were lowered 21.6% and 28.9%, respectively. Weight-training exercise appears to result in favorable changes in lipid and lipoprotein levels in previously sedentary men and women.