# Heat Acclimatization Timing **URL:** \ **Category:** Training\ **Created:** [June 30, 2025, 9:08pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230 "2025-06-30T21:08:11Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![stucknnola](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/stucknnola/32/157965_2.png) [@stucknnola](https://www.trainerroad.com/forum/u/stucknnola)\ **Post date:** [June 30, 2025, 9:08pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/1 "2025-06-30T21:08:11Z")
Hello everyone, As I approach my A event I wonder how to fit in heat Acclimatization to my training. A race is 60k MTB race with a bunch of climbing and tech. Last year it was hot and sticky and about 8 hours. As much as nailing VO2 max and threshold workouts the last two weeks before the race may help sharpen the proverbial edge of my blade, I wonder if heat acclimatization would give me more benefit in the last two weeks. I’m curious what others think. Thanks, Gary ---
**Author:** ![Samus](https://avatars.discourse-cdn.com/v4/letter/s/8edcca/32.png) [@Samus](https://www.trainerroad.com/forum/u/Samus)\ **Post date:** [June 30, 2025, 9:16pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/2 "2025-06-30T21:16:28Z")
Dylan Johnson dropped a [good video](https://www.youtube.com/watch?v=7rW6qDp9cSw) last week. I am of the strong opinion to do heat training off the bike, immediately _following_ high intensity sessions. It doesn’t have to be an either/or, as long as you’re not attempting them at the same time. Also, various TR podcasts have suggested water restriction going to sauna sessions but there’s nothing in the literature to suggest this is helpful (and there are good reasons to consider it dangerous). ---
**Author:** ![stucknnola](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/stucknnola/32/157965_2.png) [@stucknnola](https://www.trainerroad.com/forum/u/stucknnola)\ **Post date:** [June 30, 2025, 10:42pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/3 "2025-06-30T22:42:33Z")
Thanks. Listen to some more podcasts, which helped a bit. For immediately following high intensity training, hot tub at 104 for how long to get benefit and not harm? ---
**Author:** ![BCM](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/bcm/32/137631_2.png) [@BCM](https://www.trainerroad.com/forum/u/BCM)\ **Post date:** [June 30, 2025, 10:58pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/4 "2025-06-30T22:58:53Z")
> [@stucknnola](#): > > As much as nailing VO2 max and threshold workouts the last two weeks before the race may help sharpen the proverbial edge of my blade Not about heat acclimation - but the last two weeks should be a taper, not nailing VO2 and threshold workouts. heat acclimation - roughly 5 days of every day will do it according to the research. Then 2-3x a week maintenance. You could start in the first of two taper weeks, or go earlier and maintain for longer. Unsure on how long with a tub, but anecdotally 45 minutes in a cheap infrared sauna has been making a difference for me, I’d bet 30 minutes with an already elevated core temp would be fine. I am going to be taking some “core temp measurements” (don’t ask) to see what my body temp is actually doing when I’m feeling a certain way. I’ll also say that just passive heat like the sauna has been way less stress for me than the time I tried intra-workout. Even though that was just endurance, 30 minutes was pretty miserable. ---
**Author:** ![Samus](https://avatars.discourse-cdn.com/v4/letter/s/8edcca/32.png) [@Samus](https://www.trainerroad.com/forum/u/Samus)\ **Post date:** [June 30, 2025, 11:22pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/5 "2025-06-30T23:22:28Z")
> [@stucknnola](#): > > For immediately following high intensity training, hot tub at 104 for how long to get benefit and not harm? This is going to be subjective and I’m not sure what the recs are with hot tub. Look up “Rhonda Patrick” – might have some tips. Monitor your HR and make sure it’s not going nuts. Normally I’d say stay in the hot tub until it’s uncomfortable (not unbearable, just uncomfortable), then add X mins. But given that you’re so close to your race, I’d aim err on the side of being cautious. You have more to lose by overdoing it. So maybe stay in the hot tub until it’s uncomfortable. Once you’re uncomfortable, set a timer for 1 min and then call it. Repeat the next session until you’re at 20+ mins. The “uncomfortable” threshold will vary depending on a lot of factors, including your starting core temp. ---
**Author:** ![webdev511](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/webdev511/32/135558_2.png) [@webdev511](https://www.trainerroad.com/forum/u/webdev511)\ **Post date:** [July 1, 2025, 5:23am UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/6 "2025-07-01T05:23:04Z")
I think that the Core protocol is 4x a week x4 weeks then you can back off to 2x to maintain. ---
**Author:** ![eddie](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/eddie/32/129850_2.png) [@eddie](https://www.trainerroad.com/forum/u/eddie)\ **Post date:** [July 1, 2025, 12:47pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/7 "2025-07-01T12:47:02Z")
I’d definitely follow someone like [CORE’s recommendations](https://help.corebodytemp.com/en/collections/11455763-heat-training-protocols). This is something that can be dangerous, so you really want to make sure you’re using good advice. ---
**Author:** ![webdev511](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/webdev511/32/135558_2.png) [@webdev511](https://www.trainerroad.com/forum/u/webdev511)\ **Post date:** [July 1, 2025, 2:14pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/8 "2025-07-01T14:14:50Z")
This is actually a lot easier plan than what I recalled. One only needs to put the painter suit on for part of the workout until you hit week 3. Easy enough to do in TR by either adding some extra time in Z2 via the workout editor, or selecting a short z2 workout and doing it directly after your regular workout. This is very much setup for one to peak somewhere after the 5 week mark. Reading it myself I don’t think it’s sustainable for more than 8-10 weeks as it’s a LOT of work. Definitely READ THE WHOLE PLAN. > **[5-Week Introductory Heat Training Plan | CORE Help Center](https://help.corebodytemp.com/en/articles/10447172-5-week-introductory-heat-training-plan)** > > by the CORE Team ---
**Author:** ![John\_Koch](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/john_koch/32/20045_2.png) [@John\_Koch](https://www.trainerroad.com/forum/u/John_Koch)\ **Post date:** [July 1, 2025, 2:19pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/9 "2025-07-01T14:19:55Z")
> [@BCM](#): > > Not about heat acclimation - but the last two weeks should be a taper, not nailing VO2 and threshold workouts. I don’t need a 2 week taper 🤷‍♂️ ---
**Author:** ![BCM](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/bcm/32/137631_2.png) [@BCM](https://www.trainerroad.com/forum/u/BCM)\ **Post date:** [July 1, 2025, 2:37pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/10 "2025-07-01T14:37:12Z")
Need, no. But you’ll probably be better off if you do. I’ll maintain - Openers and staying fresh, certainly, but the last two weeks before a target event isn’t the time to be hitting threshold and VO2 hard. Too much fatigue for too little benefit without time to absorb and realize any gains from progressive overload. ---
**Author:** ![stucknnola](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/stucknnola/32/157965_2.png) [@stucknnola](https://www.trainerroad.com/forum/u/stucknnola)\ **Post date:** [July 1, 2025, 8:13pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/11 "2025-07-01T20:13:49Z")
The prescribed workouts are short VO2 max and Threshold workouts (30-45 minutes). Not much gain to be had. It is rather hot outside, I could just ride outside in the heat this week and some of next to get traditional heat acclimatization. Formal structured heat acclimatization training after the race when the risk is low. ---
**Author:** ![Samus](https://avatars.discourse-cdn.com/v4/letter/s/8edcca/32.png) [@Samus](https://www.trainerroad.com/forum/u/Samus)\ **Post date:** [July 1, 2025, 8:34pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/12 "2025-07-01T20:34:14Z")
> [@webdev511](#): > > One only needs to put the painter suit on for part of the workout until you hit week 3 This is way more hassle than just passive heat acclimation. Don’t mess with workouts. Hot tub & chill afterwards. > [@stucknnola](#): > > The prescribed workouts are short VO2 max and Threshold workouts (30-45 minutes). Not much gain to be had. Yeah, my understanding is that is the appropriate taper. Cut the TSS down but keep the intensity. ---
**Author:** ![webdev511](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/webdev511/32/135558_2.png) [@webdev511](https://www.trainerroad.com/forum/u/webdev511)\ **Post date:** [July 1, 2025, 9:00pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/13 "2025-07-01T21:00:04Z")
> [@Samus](#): > > This is way more hassle than just passive heat acclimation. Don’t mess with workouts. Hot tub & chill afterwards. Painter’s suit is WAY cheaper than a Hot Tub or Sauna, not to mention the water bill if you just mean a hot bath tub 4x a week for 5 weeks. Still really gross, but exceptionally cheap. ---
**Author:** ![stucknnola](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/stucknnola/32/157965_2.png) [@stucknnola](https://www.trainerroad.com/forum/u/stucknnola)\ **Post date:** [July 1, 2025, 9:19pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/14 "2025-07-01T21:19:25Z")
I have access to a proper hot tub where I train. I can easily get off the bike, change shorts, and hop in the tub. “No sweat”… Well a lot of sweat, but not much hassle. 🤣 ---
**Author:** ![BCM](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/bcm/32/137631_2.png) [@BCM](https://www.trainerroad.com/forum/u/BCM)\ **Post date:** [July 2, 2025, 12:15am UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/15 "2025-07-02T00:15:25Z")
Been doing the Amazon Sauna. Cost me about $200 and Way less stress and much prefer it to intra-workout. Disadvantage is the extra time it takes. ---
**Author:** ![AJS914](https://avatars.discourse-cdn.com/v4/letter/a/919ad9/32.png) [@AJS914](https://www.trainerroad.com/forum/u/AJS914)\ **Post date:** [July 2, 2025, 2:23am UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/16 "2025-07-02T02:23:23Z")
> [@stucknnola](#): > > For immediately following high intensity training, hot tub at 104 for how long to get benefit and not harm? I’d be careful in a hot tub. I feinted one time in a hot shower after a long hard bike ride. Most of the protocols take weeks/months. I don’t think a few sessions two weeks out from an A event is going to move the needle much. ---
**Author:** ![BCM](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/bcm/32/137631_2.png) [@BCM](https://www.trainerroad.com/forum/u/BCM)\ **Post date:** [July 2, 2025, 10:35pm UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/17 "2025-07-02T22:35:30Z")
> [@AJS914](#): > > Most of the protocols take weeks/months. I don’t think a few sessions two weeks out from an A event is going to move the needle much. Actually, not what the research says. 5 Consecutive days is what it takes according to the study I saw (at least for significant or the bulk of the adaptations), and according to multiple other discussions a similar timetable, some around a week. Multiple discussions on this, podcasts, etc. that the last two weeks before the event are the important ones. ---
**Author:** ![AJS914](https://avatars.discourse-cdn.com/v4/letter/a/919ad9/32.png) [@AJS914](https://www.trainerroad.com/forum/u/AJS914)\ **Post date:** [July 3, 2025, 4:36am UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/18 "2025-07-03T04:36:03Z")
I’ve read the Ronnestad study and it was 5 weeks long. Power at 4 mmol (threshold) increased 10 watts. After the loading phase, one usually gets to a maintenance phase of 2-3x per week. Two weeks before an event I wouldn’t be busting out the 5 days a week heat training. It sounds a bit stressful. The OP should of started 2+ months ago if they really wanted those extra watts. ---
**Author:** ![IL.Grillo](https://avatars.discourse-cdn.com/v4/letter/i/e0b2c6/32.png) [@IL.Grillo](https://www.trainerroad.com/forum/u/IL.Grillo)\ **Post date:** [July 3, 2025, 6:28am UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/19 "2025-07-03T06:28:54Z")
You are missing that the op is racing in hot and sticky conditions. Heat acclimatising now, no matter how late is the single most important thing in your training. You will be surprised how little amount of sessions, but also the stress in the sessions is required for good gains here. If you can get 4-5 20-40min sessions at a point where this feels really hot and youre sweating close to your max but not awful then that would be super beneficial, think of it like your sweetspot of heat training. If you went much hotter than this is would suck quite bad but you are are in an uncomfortable, comfortable. Most people push it way too far and also go for too long. This close to event stay well hydrated and let body cool off after, even if you eat an iceblock after your shower, the stress has already been created no need to prolong it. ---
**Author:** ![BCM](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/bcm/32/137631_2.png) [@BCM](https://www.trainerroad.com/forum/u/BCM)\ **Post date:** [July 3, 2025, 9:52am UTC](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230/20 "2025-07-03T09:52:57Z")
There are many more studies than just one. Almost every one I looked at was 2 weeks or less and while there are longer term gains, The impacts are absolutely real from shorter term too. Here’s one that’s less than 2 weeks that shows differences in cool conditions, not just hot, and looked at both VO2, LT and TT Performance: [Heat acclimation improves exercise performance - PMC](https://pmc.ncbi.nlm.nih.gov/articles/PMC2963322/#:~:text=Eight%20matched%20control%20subjects%20completed,hot%20)(55.1%20%C2%B1%202.5%20vs. It doesn’t have to be that stressful either. Passive like a Sauna aren’t bad at all and make a difference. (Honestly, so much easier than active on the bike at similar core temperature gains) Might not be your thing, But Dylan Johnson’s latest video on this is pretty good. [Next page](https://www.trainerroad.com/forum/t/heat-acclimatization-timing/104230.md?page=2)