The Claim
In studies where total energy intake was not matched between groups, protein supplementation is associated with moderate improvements in endurance performance, with a standardized mean difference (SMD) of 0.37 compared to placebo, and larger improvements when combined with carbohydrates (SMD: 0.57); these effects are observed across various athletic disciplines, though the lack of energy matching introduces confounding that may attribute benefits to additional caloric intake rather than protein per se.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
Protein supplements might give athletes a small boost in endurance, especially when taken with carbs—but it could just be because they're eating more calories overall.
See the scientific wording
In studies where total energy intake was not matched between groups, protein supplementation is associated with moderate improvements in endurance performance, with a standardized mean difference (SMD) of 0.37 compared to placebo, and larger improvements when combined with carbohydrates (SMD: 0.57). These benefits are observed in athletes across various disciplines, but the lack of energy matching introduces significant confounding, meaning the effects may reflect additional caloric intake rather than protein itself.
What the research says
1 studyThe study found that protein supplements seem to help endurance, especially with carbs, but the boost might just be from extra calories, not the protein itself—exactly what the claim says.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.