Sauna vs cold exposure — which recovery method has stronger evidence?

These solve different problems and come with different trade-offs. Sauna's strongest evidence is cardiovascular: the Finnish KIHD cohort found frequent sauna bathing (4-7x/week) linked to substantially lower cardiovascular and all-cause mortality, later replicated in a separate large cohort. Cold water immersion's evidence is more mixed — it reliably reduces muscle soreness and perceived recovery after hard training, but a randomized trial found it also blunts long-term strength and muscle growth from resistance training, likely by dampening the same signaling pathways that drive adaptation. If your goal is cardiovascular health, sauna has the stronger case. If you're doing cold plunges for recovery, doing them right after a strength session may work against your gains.