Piñero et al. 2024, Cold water immersion and resistance training-induced hypertrophy

This 8-RCT meta-analysis found that post-exercise cold water immersion attenuates resistance training-induced hypertrophy: resistance training alone produced a standardised mean difference of 0.36 for muscle growth versus 0.14 for CWI combined with resistance training, a comparative attenuation of approximately −0.22. CWI does not prevent muscle gain entirely but likely produces at least a small reduction in hypertrophic adaptation. Strong.