Research
Mixed
Protein supplementation alone does not increase muscle strength; resistance training is an absolute prerequisite for protein to exert a synergistic effect on strength gains.
Do not expect muscle strength gains from protein supplements alone. If you are not lifting weights, increasing your protein intake will not make you stronger. Protein only amplifies the strength gains generated by resistance training.
GoodRefutesHIGH confidence
Muscle strength increase was significantly augmented only with resistance training (MD 2.01%, 95% CI 1.09–2.93) and was not augmented if resistance training was absent (MD 0.13%, 95% CI −1.53 to 1.79).
Why this rating
High-quality evidence based on a meta-analysis of 82 RCTs with GRADE assessment rated as 'High' for the resistance training subgroup.
Source
Synergistic Effect of Increased Total Protein Intake and Strength Training on Muscle Strength: A Dose-Response Meta-analysis of Randomized Controlled Trials
Ryoichi Tagawa et al. · Sports Medicine - Open · 2022
Meta-analysis · 82 studiesCited 39×
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