Research

Mixed

Performing intense aerobic exercise prior to resistance training does not compromise muscle hypertrophy or strength gains and may actually enhance muscle volume increases compared to resistance training alone.

If you want to build muscle and improve cardiovascular health, you can do cardio before your weight training without worrying about losing muscle gains. In fact, this study suggests you might actually build more muscle volume by doing so. Just make sure to wait about 6 hours between your cardio and weight sessions, and perform the cardio intensely enough to challenge yourself.

GoodRefutesHIGH confidence
The results suggest that the increased aerobic capacity shown with AE+RE, was accompanied by a more robust increase in muscle size compared with RE. While this response was not carried over to greater improvement in muscle function, it remains that intense AE can be executed prior to RE without compromising performance outcome.
Tommy R. Lundberg et al. · Journal of Applied Physiology · 2012

Why this rating

Randomized controlled trial with unilateral limb comparison, MRI-verified hypertrophy, and molecular analysis, though short duration (5 weeks) and small sample size (n=10) limit generalizability.

Source

Aerobic exercise does not compromise muscle hypertrophy response to short-term resistance training

Tommy R. Lundberg et al. · Journal of Applied Physiology · 2012

DOI 10.1152/japplphysiol.01013.2012

rct · n=10Cited 166×
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DOI resolved against Crossref · corpus check 2026-06-10

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