EFFECTS OF ACUTE SMOKING AND EXERCISE ON HIGH-DENSITY LIPOPROTEIN-CHOLESTEROL AND SUBFRACTIONS IN BLACK FEMALE SMOKERS

This study investigated the effects of acute bouts of both exercise and smoking on high-density lipoprotein-cholesterol subfractions, HDL2-C and HDL3-C in black females. During two testing trials, seven subjects were exposed to either acute exercise or smoking. Treadmill exercise was performed at 70% of heart rate reserve for 15 minutes. Blood samples were taken before, immediately after, and 10 minutes after exercise. The smoking trial consisted of subjects smoking two cigarettes followed by 30 minutes of nonsmoking. Blood samples were taken before smoking, after each cigarette, and after two 15-minute intervals of nonsmoking. The exercise protocol resulted in a 10.8% increase in total HDL-C, primarily through an increase in the HDL2-C subfraction. The values returned to baseline within 10 minutes after exercise. Smoking one cigarette decreased total HDL-C by 10%. Neither subfraction was significantly effected by smoking; however, the HDL3-C subfraction was decreased 11% and HDL2-C subfraction was decreased 14.7% from resting values. The maximum reduction in HDL3-C subfraction occurred after the smoking of the first cigarette, while the maximum reduction in the HDL3-C subfraction occurred after the first 15-minute nonsmoking period. Acute cigarette smoking was associated with a decrease in total HDL-C that was maintained through 15 minutes of nonsmoking. It is suggested that the adverse effect on HDL-C by acute smoking is a significant contributor to coronary heart disease (CHD) risk in black females. Results further indicate that low-intensity exercise is capable of transiently increasing the total HDL-C via an increase in the anti-atherogenic HDL2-C subfraction. It is suggested that frequent low-intensity exercise may favorably alter the CHD risk factor profile of black females smokers. © 1990.