The effect of prolonged exercise on lipid peroxidation in eumenorrheic female runners.

Abstract

Recently a protective role has been demonstrated for estrogens as free radical scavengers. In this study, lipid peroxidation was evaluated in eumenorrheic runners before and after participation in a half-marathon. Seven female runners who participated in regular training (average 25 miles x wk(-1) and reported regular menses (12/yr) served as subjects. Subjects were all in a low estrogen phase of their menstrual cycle as confirmed by menstrual record and plasma estradiol level (42.71 +/- 21.65 pg x mL(-1). Low density lipoprotein oxidation (formation of conjugated dienes) was determined 2 h prerace and 5 min after subject's completion of the race. Results showed a significant increase in lag phase time of conjugated dienes after prolonged exercise (28.43 +/- 4.89 min vs postrace 35.21 +/- 4.32 min, P < 0.05). No correlation between mean levels of estradiol and mean lipid peroxidation levels at rest, 5 min after exercise, or difference (prepost) was observed. Prolonged endurance exercise does not appear to increase potential for lipid peroxidation in trained eumenorrheic runners during a low estrogen phase of the menstrual cycle.