Department of Dietetics, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Department of Dietetics, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Department of Dietetics, Hospital Sultan Abdul Aziz Shah, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia.
Clin Nutr. 2024 Oct;43(10):2412-2426. doi: 10.1016/j.clnu.2024.08.033. Epub 2024 Sep 5.
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.
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).
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 = 69%), 6MWT (n = 5, SMD: -0.08; 95%CI: -0.31, 0.16; I = 0%), GS test (n = 4, SMD: -0.08; 95%CI: -0.43, 0.28; I = 36%), TUG test (n = 9, SMD: 0.0, 95% CI -0.15, 0.14; I = 0%), LBM (n = 11, SMD: 0.02; 95%CI: -0.13, 0.17; I = 0%), FM (n = 15, SMD: -0.04; 95%CI: -0.18, 0.10; I = 0%). However, ASM significantly improved after WPS consumption but with high heterogeneity (n = 2, SMD: 0.39; 95%CI: 0.28, 0.51; I = 69%). In interventions incorporating RE, statistically significant positive effects of WPS on lower body strength were observed (n = 11, SMD: 0.25; 95%CI: 0.05, 0.45; I = 0%).
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.
乳清蛋白补充剂（WPS）在改善老年人肌肉力量、身体机能和身体成分方面的功效已被广泛宣传。然而，这方面的随机临床试验结果并不一致。我们旨在确定 WPS 在训练期间或不训练期间与安慰剂相比，对老年人肌肉力量、身体功能和身体成分的影响。
我们使用 PubMed、EMBASE、Cochrane 图书馆数据库和 Scopus 数据库彻底搜索了随机对照试验，截至 2024 年 6 月。分析重点关注关键参数，如握力（HS）、腿推、膝关节伸展、步行速度（GS）、6 分钟步行测试（6MWT）、起立-行走测试（TUG）、瘦体重（LBM）、体脂肪（FM）和四肢骨骼肌质量（ASM）。使用基于标准化均数差（SMD）的随机效应模型计算合并效应大小。
符合纳入标准的 30 项研究共纳入 2105 名 60 岁及以上的参与者。对 26 项 RCT 的荟萃分析显示，WPS 对 HS（n=11，SMD：0.18；95%CI：-0.13，0.49；I²=69%）、6MWT（n=5，SMD：-0.08；95%CI：-0.31，0.16；I²=0%）、GS 测试（n=4，SMD：-0.08；95%CI：-0.43，0.28；I²=36%）、TUG 测试（n=9，SMD：0.0，95%CI：-0.15，0.14；I²=0%）、LBM（n=11，SMD：0.02；95%CI：-0.13，0.17；I²=0%）和 FM（n=15，SMD：-0.04；95%CI：-0.18，0.10；I²=0%）没有显著的积极影响。然而，在 WPS 摄入后，ASM 显著改善，但存在高度异质性（n=2，SMD：0.39；95%CI：0.28，0.51；I²=69%）。在包含 RE 的干预中，WPS 对下肢力量有统计学上显著的积极影响（n=11，SMD：0.25；95%CI：0.05，0.45；I²=0%）。
本荟萃分析表明，WPS 结合抗阻训练（RT）可以增强下肢力量，但似乎对手握力、身体机能或身体成分没有显著的有益影响。需要进一步的大规模研究来证实这些发现，并阐明 WPS 在这一人群中的潜在益处。
