Health claim
“Doing steady‑state cardio for more than 45 minutes per session can impair muscle protein synthesis and hinder fat loss.”
Claim checked — mixed / earlyMedium riskexercise
Evidence Summary
Some evidence supports this, but findings are inconsistent or limited in scope.
Research shows very long cardio sessions can increase cortisol and modestly reduce muscle protein synthesis, but the impact on overall fat loss is small and depends on total energy balance.
Extracted from
The Worst Cardio Mistakes Everyone Makes For Fat Loss (Avoid These)Jeff Nippard
Jeff Nippard outlines common cardio mistakes that can hinder fat loss and offers evidence‑based alternatives.
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