in a dry sauna the temp can get somewhere near 160 or greater in some cases,,this is damaging to the skin and causes massive free radical damage to your body,,not to mention nuke your testicles and greatly increase your risk of lower sperm count, motility, and abnormally shaped sperm,,,a much better option is a lower temperature 110-120 and higher humidity tobreak a sweat..once in a while after a workout i will use the gym sauna if i can get there early in the morning when they first open before the sauna had time to heat up to "oven" temperature(i hate it when they set the dial to 10) i always try to put it back down to 5,,some gyms have a lock box covering the dial,,one time i cracked open the plexiglass cage it was encosed in and turned it down to 5, one time i opened up a paperclip to change the dial through a small opening when i could not rip the cage off the wall(i feel like macgyver sometimes), i always throw warm water on the rocks to create maximum humidity..
there are several articles on sauna and its acute effect on hormonal profile,,there is some evidence that there is a GH burst but with a concurrent rise in cortisol levels...does have a way of increasing appetite through some mechanism,,..i would love to have a low temp hot tub like 99-100