Protein supplementation and resistance training-induced strength gains in young adults: a meta-analysis.

IF 5.5 2区农林科学 Q2 NUTRITION & DIETETICS

Frontiers in Nutrition Pub Date : 2026-10-13 eCollection Date: 2026-01-01 DOI:10.3389/fnut.2026.1946052

Chenkun Zhang, Yahai Wang, Wenying Huang

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引用次数: 0

Abstract

Background: This study aimed to determine whether protein supplementation confers additional benefits for muscle strength gains beyond those induced by resistance training (RT) alone in healthy young adults.

Methods: A systematic literature search was performed in PubMed, Web of Science, Cochrane Library, and SPORTDiscus through April 1, 2026. Twenty-three randomized controlled trials involving 611 healthy young adults were included. Pooled estimates were calculated as weighted mean differences (WMD) with 95% confidence intervals (CIs) using a random-effects model. Subgroup analysis, meta-regression, and leave-one-out and leave-one-category-out sensitivity analysis were performed to explore heterogeneity.

Results: Compared with RT alone, combined RT and protein supplementation produced significant improvements in both bench press (WMD: 2.63 kg, 95% CI: 0.77-4.49, p = 0.006) and squat strength (WMD: 7.40 kg, 95% CI: 2.15-12.66, p = 0.006). Subgroup analysis revealed that the ergogenic effect on squat strength was predominantly observed when the intervention lasted ≤12 weeks, or when protein was ingested both around exercise (pre- and/or post-exercise) and before sleep. Meta-regression identified intervention duration as a significant moderator (p = 0.037) and protein timing as a borderline moderator (p = 0.073) of squat strength heterogeneity. Sensitivity analysis showed that the pooled effects remained significant and consistent in direction.

Conclusion: Protein supplementation combined with resistance training enhances muscle strength in young healthy adults, but its incremental benefit appears conditional on intervention duration, nutrient timing, training background, and baseline protein status rather than universally applicable. Future well-powered trials with standardized protein dose and source reporting, repeated measures of habitual protein intake, and stratified designs are needed to clarify these interactions and support more personalized, mechanism-informed exercise and nutrition guidance.

Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/# myprospero, PROSPERO, identifier: CRD42024534481.

查看原文本刊更多论文

蛋白质补充和阻力训练诱导的年轻人力量增加：一项荟萃分析。

背景：本研究旨在确定在健康的年轻人中，蛋白质补充是否比单纯的阻力训练（RT）更能增加肌肉力量。方法：系统检索PubMed、Web of Science、Cochrane Library和SPORTDiscus的文献，检索时间截止到2026年4月1日。纳入了23项随机对照试验，涉及611名健康年轻人。采用随机效应模型，以加权平均差（WMD）和95%置信区间（ci）计算合并估计。采用亚组分析、meta回归、遗漏一个和遗漏一个类别的敏感性分析来探索异质性。结果：与单独RT相比，联合RT和蛋白质补充显著改善了卧推（WMD: 2.63 kg, 95% CI: 0.77-4.49, p = 0.006）和深蹲力量（WMD: 7.40 kg, 95% CI: 2.15-12.66, p = 0.006）。亚组分析显示，当干预持续≤12 周时，或在运动前后（运动前和/或运动后）和睡觉前摄入蛋白质时，对深蹲强度的有氧作用主要被观察到。meta回归发现干预时间是深蹲力量异质性的显著调节因子（p = 0.037），蛋白质时间是一个临界调节因子（p = 0.073）。敏感性分析显示，合并效应在方向上保持显著和一致。结论：蛋白质补充结合抗阻训练可以增强年轻健康成人的肌肉力量，但其增量效益似乎取决于干预时间、营养时间、训练背景和基线蛋白质状态，而不是普遍适用的。未来需要标准化蛋白质剂量和来源报告、重复测量习惯性蛋白质摄入和分层设计的有力试验来澄清这些相互作用，并支持更个性化、机制知情的运动和营养指导。系统评价注册：https://www.crd.york.ac.uk/PROSPERO/# myprospero， PROSPERO，标识符：CRD42024534481。

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来源期刊

Frontiers in Nutrition Agricultural and Biological Sciences-Food Science

CiteScore

5.20

自引率

8.00%

发文量

2891

审稿时长

12 weeks

期刊介绍： No subject pertains more to human life than nutrition. The aim of Frontiers in Nutrition is to integrate major scientific disciplines in this vast field in order to address the most relevant and pertinent questions and developments. Our ambition is to create an integrated podium based on original research, clinical trials, and contemporary reviews to build a reputable knowledge forum in the domains of human health, dietary behaviors, agronomy & 21st century food science. Through the recognized open-access Frontiers platform we welcome manuscripts to our dedicated sections relating to different areas in the field of nutrition with a focus on human health. Specialty sections in Frontiers in Nutrition include, for example, Clinical Nutrition, Nutrition & Sustainable Diets, Nutrition and Food Science Technology, Nutrition Methodology, Sport & Exercise Nutrition, Food Chemistry, and Nutritional Immunology. Based on the publication of rigorous scientific research, we thrive to achieve a visible impact on the global nutrition agenda addressing the grand challenges of our time, including obesity, malnutrition, hunger, food waste, sustainability and consumer health.