Nutrition
B · Reasonable confidenceExtra protein and its timing: effect on muscle mass and strength
Subject: The role of protein intake and its timing
What this means
Extra protein added 0.62 kg of lean body mass in adults and 0.46 kg in older adults. Hand and leg strength did not clearly improve. The timing of intake made no difference.
Wirth J, Hillesheim E, Brennan L · 2020 · Journal of Nutrition 150(6):1443-1460
What does this rating mean?
A solid systematic review with caveats, or consistent indications with a limited scope.
Findings
An analysis of both the amount and the timing of protein intake in relation to body composition and muscle function.
Who this applies to
Healthy adults aged 18 to 55 and older adults over 55; roughly equal numbers of men and women.
Size of the research
65 studies with 2907 participants in total: 1514 men and 1380 women.
What to keep in mind
Data on muscle protein synthesis were scarce and inconclusive. The effect on muscle strength remains unclear and needs further research.
Practical conclusion for REZA
Timing gets attention once total intake is on point, and not before. The order of importance is total, then spread, then timing.
View method and source
Methodology
Systematic review with meta-analysis of RCTs
Original source
DOI: 10.1093/jn/nxaa049 · PMID: 32232404
View on PubMed →This information is general education about scientific research. It is not personal medical advice and does not replace diagnosis or treatment by a doctor or other healthcare professional. If you have symptoms, a medical condition or take medication, consult your GP or treating professional before changing your training or nutrition.