Contraction-induced muscle damage is unaffected by vitamin E supplementation

• Published in: Medicine and science in sports and exercise Vol. 34; no. 5; p. 798
• Main Authors: Beaton, Louise J, Allan, Damon A, Tarnopolsky, Mark A, Tiidus, Peter M, Phillips, Stuart M
• Format: Journal Article
• Language: English
• Published: United States 01.05.2002
• Subjects: Biopsy, Needle; Creatine Kinase - blood; Humans; Immunohistochemistry; Male; Muscle Contraction - physiology; Muscle Fatigue - physiology; Muscle, Skeletal - pathology; Muscle, Skeletal - physiology; Nutritional Requirements; Torque; Vitamin E - administration & dosage; Vitamin E - pharmacology
• ISSN: 0195-9131
• DOI: 10.1097/00005768-200205000-00012

Vitamin E supplementation may confer a protective effect against eccentrically biased exercise-induced muscle damage through stabilization of the cell membrane and possibly via inhibition of free radical formation. Evidence supporting a protective role of vitamin E after contraction-induced muscle injury in humans is, however, inconsistent. The present study sought to determine the effect of vitamin E supplementation on indices of exercise-induced muscle damage and the postexercise inflammatory response after performance of repeated eccentric muscle contractions. Young healthy men performed a bout of 240 maximal isokinetic eccentric muscle contractions (0.52 rad.s-1) after being supplemented for 30 d with either vitamin E (N = 9; 1200 IU.d-1) or placebo (N = 7; safflower oil). Measurements of torque (isometric and concentric) decreased (P < 0.05) below preexercise values immediately post- and at 48 h post-exercise. Biopsies taken 24 h postexercise showed a significant increase in the amount of extensive Z-band disruption (P < 0.01); however, neither the torque deficit nor the extent of Z-band disruption were affected by vitamin E. Exercise resulted in increased macrophage cell infiltration (P = 0.05) into muscle, which was also unaffected by vitamin E. Serum CK also increased as a result of the exercise (P < 0.05) with no effect of vitamin E. We conclude that vitamin E supplementation (30 d at 1200 IU.d-1), which resulted in a 2.8-fold higher serum vitamin E concentration (P < 0.01), had no affect on indices of contraction-induced muscle damage nor inflammation (macrophage infiltration) as a result of eccentrically biased muscle contractions.