Abstract
Bed rest and limb immobilization are models of muscle disuse associated with skeletal
muscle atrophy and reduced strength. The purpose of this systematic review was
to examine the impact of protein or amino acid provision before and/or during a
period of muscle disuse on muscle atrophy (primary outcome), strength and muscle
protein synthesis (secondary outcomes) following a disuse period. We performed a
systematic review of Embase, MEDLINE, Web of Science, PubMed and Clinical Trials
in December 2022. Eligible studies were randomized controlled trials that combined
a dietary protein or amino acid intervention versus control during an experimental
model of disuse (bed rest or unilateral limb immobilization) in healthy individuals
aged ≥18 years. Nine articles from eight independent trials were identified and rated
for risk of bias by two authors. A meta-analysis of muscle mass data revealed no
effect (standardized mean difference: 0.2; 95% confidence interval: −0.18 to 0.57,
P = 0.31) of protein/amino acid intervention in preventing disuse-induced muscle
atrophy. Although the meta-analysis was not conducted on strength or muscle protein
synthesis data, there was insufficient evidence in the reviewed articles to support
the use of protein/amino acid provision in mitigating the disuse-induced decline in
either outcome measurement. Additional high-quality studies, including the reporting
of randomization procedures and blinding procedures and the provision of statistical
analysis plans, might be required to determine whether protein or amino acid provision
serves as an effective strategy to attenuate muscle atrophy during periods of disuse.
muscle atrophy and reduced strength. The purpose of this systematic review was
to examine the impact of protein or amino acid provision before and/or during a
period of muscle disuse on muscle atrophy (primary outcome), strength and muscle
protein synthesis (secondary outcomes) following a disuse period. We performed a
systematic review of Embase, MEDLINE, Web of Science, PubMed and Clinical Trials
in December 2022. Eligible studies were randomized controlled trials that combined
a dietary protein or amino acid intervention versus control during an experimental
model of disuse (bed rest or unilateral limb immobilization) in healthy individuals
aged ≥18 years. Nine articles from eight independent trials were identified and rated
for risk of bias by two authors. A meta-analysis of muscle mass data revealed no
effect (standardized mean difference: 0.2; 95% confidence interval: −0.18 to 0.57,
P = 0.31) of protein/amino acid intervention in preventing disuse-induced muscle
atrophy. Although the meta-analysis was not conducted on strength or muscle protein
synthesis data, there was insufficient evidence in the reviewed articles to support
the use of protein/amino acid provision in mitigating the disuse-induced decline in
either outcome measurement. Additional high-quality studies, including the reporting
of randomization procedures and blinding procedures and the provision of statistical
analysis plans, might be required to determine whether protein or amino acid provision
serves as an effective strategy to attenuate muscle atrophy during periods of disuse.
| Original language | English |
|---|---|
| Pages (from-to) | 873-888 |
| Number of pages | 16 |
| Journal | Experimental Physiology |
| Volume | 109 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - 25 Jan 2024 |