title: Whey protein hydrolysate augments tendon and muscle hypertrophy independent of resistance exercise contraction mode.
abstract: In a comparative study, we investigated the effects of maximal eccentric or concentric resistance training combined with whey protein or placebo on muscle and tendon hypertrophy. 22 subjects were allocated into either a high-leucine whey protein hydrolysate + carbohydrate group (WHD) or a carbohydrate group (PLA). Subjects completed 12 weeks maximal knee extensor training with one leg using eccentric contractions and the other using concentric contractions. Before and after training cross-sectional area (CSA) of m. quadriceps and patellar tendon CSA was quantified with magnetic resonance imaging and a isometric strength test was used to assess maximal voluntary contraction (MVC) and rate of force development (RFD). Quadriceps CSA increased by 7.3 ± 1.0% (P < 0.001) in WHD and 3.4 ± 0.8% (P < 0.01) in PLA, with a greater increase in WHD compared to PLA (P < 0.01). Proximal patellar tendon CSA increased by 14.9 ± 3.1% (P < 0.001) and 8.1 ± 3.2% (P = 0.054) for WHD and PLA, respectively, with a greater increase in WHD compared to PLA (P < 0.05), with no effect of contraction mode. MVC and RFD increased by 15.6 ± 3.5% (P < 0.001) and 12-63% (P < 0.05), respectively, with no group or contraction mode effects. In conclusion, high-leucine whey protein hydrolysate augments muscle and tendon hypertrophy following 12 weeks of resistance training - irrespective of contraction mode.
authors: Section of Sport Science, Department of Public Health, Aarhus University, Aarhus, Denmark.
authors: J
authors: J
authors: Farup
authors: S K
authors: SK
authors: Rahbek
authors: M H
authors: MH
authors: Vendelbo
authors: A
authors: A
authors: Matzon
authors: J
authors: J
authors: Hindhede
authors: A
authors: A
authors: Bejder
authors: S
authors: S
authors: Ringgard
authors: K
authors: K
authors: Vissing
mesh_terms: D004040:Dietary Carbohydrates; D019587:Dietary Supplements; D004311:Double-Blind Method; D004576:Electromyography; D015444:Exercise / Q000502:physiology; D006801:Humans; D006984:Hypertrophy; D007930:Leucine / Q000008:administration & dosage; D008279:Magnetic Resonance Imaging; D008297:Male; D008894:Milk Proteins; D009119:Muscle Contraction / Q000502:physiology; D053580:Muscle Strength; D017847:Patellar Ligament / Q000033:anatomy & histology*; D011492:Protein Hydrolysates; D052097:Quadriceps Muscle / Q000033:anatomy & histology* / Q000502:physiology; D055070:Resistance Training / Q000379:methods*; D000067816:Whey Proteins; D055815:Young Adult
chemical_list: D004040:Dietary Carbohydrates; D008894:Milk Proteins; D011492:Protein Hydrolysates; D000067816:Whey Proteins; D007930:Leucine
keywords: concentric training; eccentric training; isotonic; patellar tendon; rate of force development; strength training