Sauna: the heat that science learned to take seriously

What the studies suggest

Long-term research, especially in populations that use saunas frequently, links the regular habit to lower cardiovascular risk and broad health benefits. There's also evidence of improved relaxation, sleep quality and relief of muscle and joint aches. It's no standalone miracle — it's a habit that adds up within an active lifestyle.

How to use it

• Frequency: the biggest benefits in studies appear in people who use it several times a week.
• Duration: 15 to 20 minute sessions, respecting your limit.
• Hydrate: you lose plenty of fluid and electrolytes in sweat. Replace water and, if you sweat heavily, salt.
• Timing: after training, the sauna pairs well with relaxation — and unlike ice, heat doesn't appear to hurt hypertrophy.

The cautions

Intense heat stresses the cardiovascular system. Pregnant women, cardiac patients, people with unstable blood pressure and anyone who has been drinking should be cautious or avoid it. Never use it alone if you tend to feel faint, and step out at the first sign of dizziness.

A word from the Lair: this content is informational and does not replace medical care. People with cardiovascular conditions or who are pregnant should consult a doctor before regular sauna use.