The Effects Of A Protease Enzyme Blend On The Amino Acid Response To Resistance Exercise

Abstract

PURPOSE: The aim of the current study was to examine the efficacy of whey protein ingestion with or without a protease enzyme complex on amino acid (AA) availability following acute lower-body resistance exercise. METHODS: Ten resistance trained men (24.4±4.1yr, 179.1±8.6cm, 92.6±10.4kg) with at least one year of resistance training experience volunteered to participate in this placebo-controlled, randomized, cross-over designed study. Following an overnight fast, participants performed lower-body acute resistance exercises consisting of four sets each of the leg press and leg extension exercises (8-10 repetitions at 75% of 1RM) followed by consumption of one of three drinks of equivalent volume, taste, and appearance which consisted of either: (a) 26g whey protein + 250 mg protease supplement + whey (PW) (b) 26g whey protein (W), or (c) a non-caloric flavored water drink (PL). Blood samples were collected before exercise, immediately-post (0min), 30-, 60-, 90-, 120-, and 180-minutes post-exercise (30min, 60min, 90min, 120min, 180min respectively). Plasma amino acid samples were analyzed for essential (EAA), branched-chained (BCAA), and leucine concentrations via liquid chromatography-mass spectrometry (LC-MS). A 2-way repeated measures analysis of variance (ANOVA) was used to identify differences between treatments over time. Area under the curve was calculated via the trapezoidal technique and analyzed via a one-way ANOVA. RESULTS: Significant main effects for time (p<0.001) and time x group interactions (p<0.001) were found for leucine, BCAA, and EAA. PW drink resulted in significantly greater plasma leucine, BCAA and EAA concentrations at 30 min compared to PL (p<0.001) while not different than W. Leucine was significantly elevated at 30min (p=0.007) and EAAs at 180min (p=0.004) compared to 0min for PW. The AUC for PW and W were both significantly elevated for leucine, BCAAs and EAAs compared to PL (p<0.001). CONCLUSION: While no significant differences were found between the W and PW supplementation groups during the 3-hr period after resistance training; the PW group produced significantly greater leucine concentrations at 30min and for EAAs at 180min than PL compared to 0min. Results indicate that PW may provide a modest improvement of AA appearance in blood following acute resistance exercise.