Research
Mixed
Concurrent endurance and resistance training attenuates gains in muscle hypertrophy and strength compared to resistance training alone, a phenomenon termed the 'interference effect'.
If your primary goal is maximizing muscle size or strength, be aware that adding significant endurance training (especially running) can blunt those gains. To minimize this interference, separate your endurance and resistance sessions by at least 6-8 hours, or prioritize resistance training first in the same session.
GoodSupportsHIGH confidence
During concurrent training muscle is repeatedly subjected to divergent contractile stimuli and the specificity of adaptive response is altered to such an extent that gains in hypertrophy, strength and power are typically attenuated compared to when resistance training is undertaken in isolation (Wilson et al., 2012).
Why this rating
Supported by meta-analysis (Wilson et al., 2012) and multiple chronic studies cited.
Source
Concurrent exercise training: do opposites distract?
Vernon G. Coffey et al. · The Journal of Physiology · 2016
narrative_reviewCited 338×
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