Macro partitioning
Timing of protein ingestion (before vs. after resistance training) does not significantly affect total body lean mass gains.
You do not need to rush to drink protein immediately after your workout. As long as you consume your protein within a few hours before or after training, your muscle growth will be the same. Focus on getting enough total protein throughout the day rather than stressing about the exact timing.
Lean body mass was not differently modulated by protein supplementation timing (SMD: −0.08; 95% CI: −0.398 to 0.244; I2 = 0%, p = 0.641).
Why this rating
The evidence is rated low/very low by the authors themselves due to risk of bias and imprecision (few studies, small sample sizes for specific outcomes).
Source
Does Protein Ingestion Timing Affect Exercise-Induced Adaptations? A Systematic Review with Meta-Analysis
Rafael A. Casuso et al. · Nutrients · 2025
DOI 10.3390/nu17132070
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