The effects of prophylactic protease supplementation on markers of muscle damage prior to and following intense eccentric exercise: preliminary findings

Methods 20 aerobically-active (50.15 ± 6.16 ml/kg/min) male participants (22.05 ± 4.72 yr, 71.63 ± 2.51 in, 182.40 ± 26.89 lbs) consumed either a proteolytic enzyme combination (N = 10) or cellulose placebo (N = 10) for a total of 24 days. Supplement compliance was monitored via supplement logs indicating how many capsules were consumed each day during the period. During the supplement period, participants also agreed to limit consumption of antioxidant containing foods. Dietary compliance was monitored by the collection of food records for each day of the supplement period. After 21 days of supplementation, participants completed a 45-minute downhill run (60% VO2max, -17.5% grade). Participants donated blood prior to, and for 48 hours following the run (total of 6 samples). Inflammation and muscle damage were assessed by whole blood analysis, serum creatine kinase (CK), ratings of perceived muscle soreness, and via muscle strength testing of the quadriceps. Whole blood and muscle strength data were analyzed using multivariate analyses of variance (MANOVA) with repeated measures, while CK and muscle soreness were analyzed using separate one-way analyses of variance (ANOVA) with repeated measures. An alpha level of ≤ 0.05 was adopted for significance throughout.