I have been asked about how to structure a sauna routine twice in a single week, so I guess here is the generalized answer on this topic.

Most people figure out their routine over time, and it usually boils down to listening to your own body, but if you mimick the wrong people you just might stumble into a style that does not suit you, leading you to think that sauna is not for you. But I think "listening to the body" can be operationalized a bit better, so you know what to look out for and maybe have a better preselection at a style that suits you.

Finally I conclude with a overgeneralized tl;dr, because much of it is also kind of obvious.

Factors involved

People have been wondering what is so healthy about it and proposed very complex models, but in the end it seems to boil down to:

• the change between heat and cold is stimulating the immune system andk helping the lymphatic system
• it is relaxing and kind of meditative
• it is social

Consequently we have validation that we can just do what we enjoy and feel is good for us, because there are no magic buttons to push.

Temperature

The first difference that comes to mind is whether your sit up or lie down, and how hot you like it. I feel like lying down is more for people with a bit of weaker cardiovascular system and it makes overall for a more relaxing, less intense experience. Temperature is similar to that, hotter sauna are harder on the body and some people just like it hotter, others like it not so hot. Sometimes you have no choice in sauna temperature, and the only way to modulate temperature is by sitting higher up or lower down in the sauna.

Costs

My sauna routine happens in the context of a somewhat active lifestyle and lifting heavy weights around four times a week. So there are three major costs for me to consider

• the heat stress
• the anti-inflammatory effect of cold on muscles I just trained
• the time commitment

Heat stress is an important factor, as systemically, all stress is stress and will interfere with your gainz. It is suggested that cooling muscles which have been trained reduces the effect of the training, because some of the processes set in motion by the training will inhibited. This seems to be mostly mediated via inflammatory pathways and with NSAIDs we have some evidence of them interfering with muscle gains, which is good enough for me; it lines up with what we observe in the field.

Practically speaking, cooling down a muscle or just taking cold showers even without the context of lifting, seems to make the muscle less sore the next day. So this is a good idea if one needs to perform the next day, but there is a possibility of it interfering with tissue accretion.

Time cost is pretty obvious. Going to the sauna takes some time and you possibly need to get there as well, and anything you get out of sauna should be worth that.

Mass

Heating up a 90kg body to the core takes longer than heating up a 70kg body or even a 50kg body. Think about microwaving a large meal; if you only put it in for a few minutes on the highest setting, you often get the outside very hot, but inside it is pretty cold. To circumvent this, you can mix the meal inbetween heating, or you can just put it into the microwave for a few minutes, wait a few minutes so the heat has a chance to dissipate towards the core, and then reheat again. Or you just use a lower setting and let it inside the microwave for longer.

My own routine

I go to the sauna one or maybe two times a week, after training, because the sauna is at the gym and I am just not going to the gym only for sauna.

Since I like it hot and am on the heavy side of things, I do two or three shorter bouts of eight to 15 minutes in the hottest sauna, sitting in the hotter spots, upright. The duration is mostly dependent on the actual temperature in the sauna and then I basically wait until breathing becomes moderately uncomfortable; a bit more than slightly uncomfortable.

Usually that's a good point to leave; up until then being in the sauna is pretty relaxing, but I do not think it's necessary or wise to push things, so when I would need to push myself to stay inside the sauna, well, I leave.

I then follow up with a cold shower and then some rest. Usually after the second round the cold shower feels very nice and refreshing instead of just cold, but if not and time permits it, I go for a third round, just to get a bit more warmth.

The tl;dr

I think the tl;dr is

• the fitter you are, the hotter and more upright you can sauna, if you want to
• the more concerned with muscle growth you are, the less you want to cool down trained areas
• don't push yourself, but find a good level of slight discomfort before leaving the sauna
• remember that heat stress is stress and adds to your total systemic stress
• the heavier you are, the longer and more intermittent you need to sauna
• if you tried a few different styles and still don't like it, well, you do not like it and you definitely do not have to push yourself to sauna