Macro partitioning
Whey protein is the only protein source shown to have statistically significant effects on both endurance performance and muscle strength in this meta-analysis.
If you use protein supplements for performance, whey protein is the only source with demonstrated significant benefits for both endurance and strength in this analysis. Other sources (soy, casein, etc.) did not show significant effects.
Only one protein source (whey protein) showed statistically significant effects for both endurance performance [μ(SMD): 0.28, 95% CI: 0.07 to 0.49... ] and muscle strength [μ(SMD): 0.53, 95% CI: 0.01 to 1.05... ]. No statistically significant effects were observed in other types of protein sources.
Why this rating
Based on subgroup analysis; other protein types had non-significant results, but sample sizes for specific types may vary.
Source
The effectiveness of protein supplements on athletic performance and post-exercise recovery − a Bayesian multilevel meta-analysis of randomized controlled trials
Shiao Zhao et al. · Journal of the International Society of Sports Nutrition · 2025
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