The response of muscle protein synthesis following whole‐body resistance exercise is greater following 40 g than 20 g of ingested whey protein

Abstract

The currently accepted amount of protein required to achieve maximal stimulation of myofibrillar protein synthesis (MPS) following resistance exercise is 20–25 g. However, the influence of lean body mass (LBM) on the response of MPS to protein ingestion is unclear. Our aim was to assess the influence of LBM, both total and the amount activated during exercise, on the maximal response of MPS to ingestion of 20 or 40 g of whey protein following a bout of whole‐body resistance exercise. Resistance‐trained males were assigned to a group with lower LBM (≤65 kg; LLBM n = 15) or higher LBM (≥70 kg; HLBM n = 15) and participated in two trials in random order. MPS was measured with the infusion of 13C6‐phenylalanine tracer and collection of muscle biopsies following ingestion of either 20 or 40 g protein during recovery from a single bout of whole‐body resistance exercise. A similar response of MPS during exercise recovery was observed between LBM groups following protein ingestion (20 g – LLBM: 0.048 ± 0.018%·h−1; HLBM: 0.051 ± 0.014%·h−1; 40 g – LLBM: 0.059 ± 0.021%·h−1; HLBM: 0.059 ± 0.012%·h−1). Overall (groups combined), MPS was stimulated to a greater extent following ingestion of 40 g (0.059 ± 0.020%·h−1) compared with 20 g (0.049 ± 0.020%·h−1; P = 0.005) of protein. Our data indicate that ingestion of 40 g whey protein following whole‐body resistance exercise stimulates a greater MPS response than 20 g in young resistance‐trained men. However, with the current doses, the total amount of LBM does not seem to influence the response.

Native whey induces higher and faster leucinemia than other whey protein supplements and milk: a randomized controlled trial

“…Nevertheless, the lighter participants did to some extent reach higher leucine levels with native whey than heavier participants. This observation is in line with a recent study finding no differences in the time dependent changes in blood leucine concentrations after intake of 20 g of whey protein in a group with low lean mass (<65 kg) to a group with high lean mass (>70 kg) [29]. Combined these findings might suggest that a certain amount of leucine is needed on order for leucine kinetics to be affected by body mass.…”

Pre-Sleep Protein Ingestion to Improve the Skeletal Muscle Adaptive Response to Exercise Training

“…Ingestion of 20 g egg or whey protein has been shown sufficient to maximize muscle protein synthesis rates during recovery from lower-body resistance-type exercise in young males [4,5]. More recent evidence indicates that this dose-response relationship may depend on the amount of muscle tissue that was recruited during exercise, with the ingestion of 40 g protein further increasing muscle protein synthesis rates during recovery from whole-body resistance-type exercise [13]. …”

Protein timing during the day and its relevance for muscle strength and lean mass

“…Specifically, the amount and distribution of protein throughout the day is associated with positive changes in body composition (Houston et al, 2008;Loenneke et al, 2010Loenneke et al, , 2016Adechian et al, 2012), bone health (Loenneke et al, 2010) and muscle function (Deutz et al, 2014). It has been demonstrated that there is a dose-response in muscle protein synthesis (MPS) with regard to protein ingestion , with the synthetic response plateauing around 20-40 g depending on the age group (Cuthbertson et al, 2005), amount of exercise (Macnaughton et al, 2016) and quality of protein Norton et al, 2009;Yang et al, 2012). Interestingly, the literature with regard to protein timing has primarily focused on increased MPS in response to an exercise stimulus (Burd et al, 2009).…”