
Cardio doesn't cost you muscle or max strength. It can blunt explosive power (jumps, dynos, freestyle), mostly when it's in the same session. So keep the power and skill work fresh and first, and put runs or long swims at least 3 hours away, or on another day.
S Evidence: strong. Large trials or many studies, pointing the same way.
Across 43 studies, adding aerobic training to strength training didn't reduce muscle growth (SMD -0.01) or max strength (-0.06), but did reduce explosive strength (-0.28), only when done in the same session; with 3+ hours between, the effect disappeared (Schumann et al. 2022, meta-analysis, 🟢) · "cardio kills gains is overstated": Chris Heria (🟠).
Not medical, legal or financial advice.
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