Abstract
The purpose of this investigation was to determine if creatine supplementation assisted with reducing the amount of exercise induced muscle damage and if creatine supplementation aided in recovery from exercise induced muscle damage. Two groups of subjects (group I = creatine; group 2 = placebo) participated in an eccentric exercise protocol following 7 and 30 days of creatine or placebo supplementation (20 gd-l for 7 d followed by 6gd-1 for 23 d = 30 d). Prior to the supplementation period, measurements were obtained for maximal dynamic strength, maximal isometric force, knee range of motion, muscle soreness, and serum levels of creatine kinase (CK) and lactate dehydrogenase(LDH). Following 7 days of creatine supplementation,
on day 8, subjects began consuming 6 gd-l of creatine for 23 days. Additionally on days 8 and 31, subjects perfonned an eccentric exercise protocol using the knee extensors to induce muscle damage. Indirect markers of muscle damage, including maximal isometric force, knee range of motion, muscle soreness, and serum levels ofCK and LDH, were collected at 12,24, and 48 hours following each exercise bout. The results indicated that acute bouts of creatine have no effect on indirect markers of muscle damage for the acute (7 days) bout. However, maximal isometric force was greater for the creatine group versus placebo for the chronic (30 days) bout. This suggests that the ergogenic effect of creatine following 30 days of supplementation may have a positive impact on exercise induced muscle damage.
