Research

Mixed

Untrained individuals may experience greater improvements in maximal oxygen uptake (VO2max) from protein supplementation during endurance training compared to trained individuals.

If you are new to endurance training, adding protein supplements might help slightly improve your maximum oxygen uptake (VO2max). This benefit is likely not present if you are already a trained endurance athlete.

GoodQualifiesMEDIUM confidence
While the overall impact on maximal oxygen uptake (VO2max) was not significant, subgroup analysis revealed that untrained individuals may experience greater improvements in VO2max with protein supplementation (SMD = 0.21).
Yang Xiao et al. · Frontiers in Nutrition · 2025

Why this rating

Derived from subgroup analysis of a high-quality meta-analysis.

Source

Effects of protein supplementation on body composition, physiological adaptations, and performance during endurance training: a systematic review and meta-analysis

Yang Xiao et al. · Frontiers in Nutrition · 2025

DOI 10.3389/fnut.2025.1663860

Meta-analysis · 23 studiesCited 2×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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