What it is
Deliberate heat exposure (sauna) and cold exposure (cold immersion, cold showers) are stress practices used for recovery and general health. Both have long cultural histories and growing research literatures.
What is currently understood
Regular sauna use is associated with cardiovascular and mortality benefits in large observational cohorts, particularly from Finland. Cold exposure has documented acute effects on alertness and some evidence for mood.
What is not established
Observational sauna data cannot fully separate the practice from the lifestyle around it. Many cold-exposure claims — fat loss, immunity, hormone effects — are extrapolated well beyond the human evidence, and cold immersion immediately after strength training may blunt adaptation.
Regulatory status
Not applicable — this is a lifestyle and behaviour topic, not a regulated product.
How it comes up in coaching
Both are tools, sequenced around training rather than stacked blindly. Coaching decides where they fit your week and your actual recovery data. Nothing here is a recommendation.
This page is educational. It is not medical advice, not a recommendation, and not an offer to supply anything. Whether any intervention is appropriate for you is a decision for a licensed provider.