筋トレ時の蛋白投与：メタ解析

蛋白投与は筋トレによる筋肉量・筋力増加を改善させるというメタ解析を紹介します。

Cermak NM, Res PT, de Groot LC, Saris WH, van Loon LJ. Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis. Am J Clin Nutr. 2012 Dec;96(6):1454-64.

22のランダム化比較試験のメタ解析の結果、若年者でも高齢者でも、6週間以上の筋トレ時の蛋白投与によって除脂肪体重が0.69kg、レッグプレスの1RMが13.5kgが増加しました。これより筋トレ時の蛋白投与は筋肉量・筋力増加に有効という結論です。

抄録しか読めていないので詳細不明ですが、高齢者でも筋トレに蛋白投与併用で筋肉量・筋力がより増加するというメタ解析でのエビデンスは意味があります。リハ栄養的には、身体機能改善まで検証されてほしいところですが。それでもリハの現場でもっと蛋白投与を取り入れるべきだと思います。

Abstract

BACKGROUND:

Protein ingestion after a single bout of resistance-type exercise stimulates net muscle protein accretion during acute postexercise recovery. Consequently, it is generally accepted that protein supplementation is required to maximize the adaptive response of the skeletal muscle to prolonged resistance-type exercise training. However, there is much discrepancy in the literature regarding the proposed benefits of protein supplementation during prolonged resistance-type exercise training in younger and older populations.

OBJECTIVE:

The objective of the study was to define the efficacy of protein supplementation to augment the adaptive response of the skeletal muscle to prolonged resistance-type exercise training in younger and older populations.

DESIGN:

A systematic review of interventional evidence was performed through the use of a random-effects meta-analysis model. Data from the outcome variables fat-free mass (FFM), fat mass, type I and II muscle fiber cross-sectional area, and 1 repetition maximum (1-RM) leg press strength were collected from randomized controlled trials (RCTs) investigating the effect of dietary protein supplementation during prolonged (>6 wk) resistance-type exercise training.

RESULTS:

Data were included from 22 RCTs that included 680 subjects. Protein supplementation showed a positive effect for FFM (weighted mean difference: 0.69 kg; 95% CI: 0.47, 0.91 kg; P < 0.00001) and 1-RM leg press strength (weighted mean difference: 13.5 kg; 95% CI: 6.4, 20.7 kg; P < 0.005) compared with a placebo after prolonged resistance-type exercise training in younger and older subjects.

CONCLUSION:

Protein supplementation increases muscle mass and strength gains during prolonged resistance-type exercise training in both younger and older subjects.