Research
Mixed
Performing high-intensity interval training (HIIT) before resistance training (HIIT+RT) does not attenuate lower-body maximal strength or lean mass gains compared to resistance-only training, making it a viable strategy for concurrent training.
If you must do cardio and weights on the same day, doing cardio first won't hurt your strength or muscle growth, provided you wait about 3 hours between sessions. You can still get strong and build muscle.
GoodRefutesHIGH confidence
After 9 weeks, all training groups increased leg press 1-RM (~24–28%) and total lean mass (~3-4%), with no clear differences between groups.
Why this rating
Same study design as N1, robust findings for strength/lean mass.
Source
Order of same-day concurrent training influences some indices of power development, but not strength, lean mass, or aerobic fitness in healthy, moderately-active men after 9 weeks of training
Matthew J-C Lee et al. · PLoS ONE · 2020
rct · n=29Cited 44×
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