stacy sims, once the chief scientist at osmo nutrition, worked on a sauna protocol for heat and altitude adaptation.
could not find her proper protocol online but you find a summary below and its described here: https://bikerumor.com/...aling-with-the-heat/
seems pretty simple to me if you have access to a sauna after your workouts for 7 days in a row.
here a summary of the basics:
Within 30 minutes of finishing training, you want to be in the sauna. In these 30 minutes, you wonâ€™t rehydrate, (your protein recovery drink is okay, but no other fluid). The strong stimulus of some dehydration is key to the adaptations of this protocol. The MOA: with dehydration, there is reduced blood flow (due to less blood volume). When you head into the sauna, the hot environments signals blood to come to the skin for thermoregulation. With this, there is decreased blood flow to other organs, in particular the kidneys. With reduced blood flow, there is reduced oxygen- registered as a drop in the partial pressure of oxygen at the level of the kidney stimulates EPO and plasma volume production. The other aspect is the strong heat stress â€śresetsâ€ť your thermoregulation thresholds- eg you will start sweating sooner, and your sweat will be more dilute (thus racing, 100â€™F will *feel* like 65â€™F).
Do this seven (7) days in a row. The first day you may only tolerate 5-10 minutes, by the 7the day, 25-30 minutes is attainable. SLOWLY REHYDRATE OVER THE COURSE OF 3-4 HOURS; otherwise, you â€śkillâ€ť the stress response to increase blood volume and reset thermoregulation set-points. The best way to monitor hydration is to use pee sticks. You may find your USg post sauna is>1.035. Slowly rehydrate to reach 1.010-1.015 (this should be your morning urine status!).
This protocol works for both heat and altitude. The connection between the two environments is the blood volume expansion- increased red cell for oxygen uptake and delivery plus increased plasma volume for circulation and sweating.
Sauna bathing is similar to hard exercise in terms of the responses of your cardiovascular system and hormones involved with controlling your blood and body fluid volumes. Therefore, sauna bathing should be maintained only for as long or as hot as you feel comfortable. Above all, it should not be undertaken in a competitive manner!
do not drink (alcohol) and sauna, etc, etc.