Mixed
Concurrent resistance and endurance training combined with high protein availability (2 g/kg/day) does not impair maximal strength or muscle hypertrophy compared to resistance training alone, but it does attenuate anaerobic power gains.
If you want to train for both strength and endurance, do them on separate days (e.g., Monday/Wednesday/Friday for weights, Tuesday/Thursday/Saturday for cardio). Eat 2 grams of protein per kilogram of body weight daily. You will likely gain strength and muscle just as well as if you only lifted weights, but you might not get as fast or powerful as if you only lifted weights.
Despite high protein availability, select measures of anaerobic power-based adaptations, but not muscle strength or hypertrophy, appear susceptible to ‘interference effects’ with CET and should be closely monitored throughout training macro-cycles.
Why this rating
Randomized controlled trial with adequate sample size (n=32), clear protocols, and statistically significant results for primary outcomes.
Source
Adaptations to Concurrent Training in Combination with High Protein Availability: A Comparative Trial in Healthy, Recreationally Active Men
Baubak Shamim et al. · Sports Medicine · 2018
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