Favorable and prolonged changes in blood lipid profile after muscle-damaging exercise

Abstract

Purpose: To examine the effect of repeated muscle-damaging exercise on the time-course changes in blood lipid and lipoprotein profile and compare them with changes in indices of muscle function and damage. Methods: Twelve women underwent an isokinetic exercise session consisting of 75 eccentric knee flexions, which was repeated after 3 wk. Triacylglycerols (TG), total cholesterol (TC), and high-density lipoprotein cholesterol (HDLC) in plasma were measured before, immediately, 1, 2, 3, 4, and 7 d after muscle-damaging exercise. Low-density lipoprotein cholesterol (LDLC) and TC/HDLC were also calculated. Results: The largest changes in TG and lipoproteins appeared 3 d after exercise, returning toward baseline thereafter. The magnitudes of these changes at 3 d compared with rest were -18% and -8% for TG, -14% and -10% for TC, 8% and 7% for HDLC, -25% and -18% for LDLC, and -20% and -15% for TC/HDLC after sessions I and 2, respectively. In addition, the incremental or decremental area under the curve for the TG and lipoproteins measured after the first session was higher than that after the second session-except for HDLC concentration. Conclusion: These findings reveal that lipid and lipoprotein profile was favorably affected by both sessions of muscle-damaging exercise but relatively less so after a repeated session of muscle-damaging exercise.