Effectiveness of whey protein supplementation on muscle strength and physical performance of older adults: A systematic review and meta-analysis of randomized clinical trials.
Study Goal
The researchers aimed to determine the impact of whey protein supplement (WPS) compared to a placebo, with or without training, on muscle strength, physical function, and body composition in older adults.
Results Summary
The meta-analysis found that WPS combined with resistance training (RT) improved lower body strength but showed no significant benefit for handgrip strength, physical performance, or body composition.
Population
Older adults aged 60 and above.
Effective Dosage
Not specified in the abstract.
Duration
Not specified in the abstract.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
whey protein supplement (WPS) | no change | handgrip strength (HS) | older adults | SMD: 0.18; 95% CI: -0.13, 0.49 | no significant positive effect | #1 |
whey protein supplement (WPS) | no change | leg press | older adults | SMD: 0.19; 95% CI: -0.02, 0.40 | no significant positive effect | #2 |
whey protein supplement (WPS) | no change | knee extension | older adults | SMD: 0.15; 95% CI: -0.04, 0.34 | no significant positive effect | #3 |
whey protein supplement (WPS) | no change | gait speed (GS) | older adults | SMD: 0.08; 95% CI: -0.08, 0.24 | no significant positive effect | #4 |
whey protein supplement (WPS) | no change | 6-min walking test (6MWT) | older adults | SMD: 0.10; 95% CI: -0.10, 0.30 | no significant positive effect | #5 |
whey protein supplement (WPS) | no change | Timed-up and go test (TUG) | older adults | SMD: -0.04; 95% CI: -0.21, 0.13 | no significant positive effect | #6 |
whey protein supplement (WPS) | no change | lean body mass (LBM) | older adults | SMD: 0.12; 95% CI: -0.02, 0.26 | no significant positive effect | #7 |
whey protein supplement (WPS) | no change | fat mass (FM) | older adults | SMD: -0.04; 95% CI: -0.18, 0.10 | no significant positive effect | #8 |
whey protein supplement (WPS) | no change | appendicular skeletal muscle mass (ASM) | older adults | SMD: 0.10; 95% CI: -0.04, 0.24 | no significant positive effect | #9 |
whey protein supplement (WPS) combined with resistance training (RT) | increase | lower body strength | older adults | - | can enhance | #10 |
whey protein supplement (WPS) | no change | handgrip strength | older adults | - | does not seem to have a significant beneficial effect | #11 |
whey protein supplement (WPS) | no change | physical performance | older adults | - | does not seem to have a significant beneficial effect | #12 |
whey protein supplement (WPS) | no change | body composition | older adults | - | does not seem to have a significant beneficial effect | #13 |
BACKGROUND: The efficacy of whey protein supplement (WPS) in improving muscle strength, physical performance, and body composition in older adults has been widely promoted. However, the results of randomized clinical trials in this regard have been inconsistent. We aimed to determine the impact of WPS, compared to a placebo, during or without training on muscle strength, physical function, and body composition in older adults. METHODS: Randomized controlled trials were thoroughly searched using PubMed, EMBASE, the Cochrane Library Database, and Scopus databases up to June 2024. The analysis focused on key parameters such as handgrip strength (HS), leg press, knee extension, gait speed (GS), 6-min walking test (6MWT), Timed-up and go test (TUG), lean body mass (LBM), fat mass (FM), and appendicular skeletal muscle mass (ASM). A pooled effect size was calculated using a random-effects model based on standardized mean differences (SMD). RESULTS: Thirty studies involving 2105 participants aged 60 and older met the inclusion criteria. The meta-analysis of 26 RCTs showed no significant positive effect of WPS on HS (n = 11, SMD: 0.18; 95% CI: -0.13, 0.49; I CONCLUSION: The present meta-analysis indicates that WPS, when combined with resistance training (RT), can enhance lower body strength but does not seem to have a significant beneficial effect on handgrip strength, physical performance, or body composition. Further large-scale studies are necessary to confirm these findings and elucidate the potential benefits of WPS in this population.