Carbonfiberboy 

Although HSP production seems to be a side effect of raising body temperature whether by exercise or other means. Thus riding in the Seattle winter rain might not produce the effect, bummer. I did a lot of that. OTOH, build a sauna in your basement! I would have loved that post-ride.
https://www.sciencedirect.com/scienc...31556521002916

MoAlpha

Love me a sauna, but I’m pretty sure vigorous exercise at any temp gives you all the HSPs you need.

Hermes

I take my climbing temperatures as I find them but I have to derate the engine as temperature increases. I go to the gym most days and use the steam room / or sauna. There is a sauna protocol for altitude adaptation. It is not pretty. After a cycling workout, immediately, one goes into the sauna for at least 20 minutes, sitting and no water and no water for at least an hour afterword. Have a nice day.

MoAlpha

To get the full effect, you need to follow the heat with ice water immersion, right? It would send me into V-fib arrest, but you hard guys should do it. The Finns I've sauna'd with drank beer in there.

Calsun

Heat is fine unless you are on pavement. I used to run cross country in the California southern deserts and no issues in 100 plus degree weather. I made the mistake of doing a 100 mile bike ride from Altadena to Cabezon to see friends during the summer. The heat coming up from the pavement was intense and I came close to having heat stroke.

I came close when riding in the Dallas area where the high humidity made sweating far less effective in maintaining a good core temperature. A local who was participating in the Olympic marathon trials in Texas did experience heat stroke and died as a result.

Kabuki12

Last year during a heat wave I decided to ride to the coast. My original plan was to do a round trip of about 35 miles. As I left my house I could feel the heat from the road so I detoured up one of our canyons which is shady. It is about 5 miles of steady , gentle climbing. Usually the trip out cools you down . By the time I got out of the canyon I was not feeling that good and it was about 9:30 in the morning . The temp was 106 and I could not cool down , even pouring water on my head. I called my wife to come and get me. It wasn’t something I care to ever do again.

rumrunn6

I had an episode that I think was heat related. had to lay down on the ground in some shade, until I could get up again, about 20 minutes. I was lucky that there was a nearby body of water to jump in that was a downhill roll from that spot. that saved me. then I was able to find my way back to my car. it would have been tough if I couldn't get underwater

Calsun

Many people monitor their heart rate while riding and it may be worthwhile to also monitor body core temperature on very hot days while bicycling. The smartwatches may not be completely accurate but seeing a core temp reading go over 100 degrees would be a good warning to get off the road and out of the sun.

Usually my legs tire or I get out of breath and my heart is being overworked but bicycling in the Dallas area in the summer I could tell that my body core was getting too hot and I needed to slow down. First time in my life where I experienced this. In the summer months people would go to an air conditioned gym to exercise and get a good workout.

With more and more heat islands in urban areas the likelihood of getting heat stroke is increasing each year and something to keep in mind.

Carbonfiberboy 

HR is by far the best way to monitor dehydration. One sees a definite rise in HR for the effort. When you stop, your HR will remain abnormally high. Of course one has to have some experience with HR to notice that. The other good tell is that your forearms become dry. That's a very serious tell because your body temperature will rise rapidly once you stop sweating! Unfortunately sun sleeves hide that tell. If it's that latter problem, one needs to get in the shade stat and drink water until urine is passed.

MoAlpha

Just a few informational points here.

You can't read skin, let alone core, temp from a smartwatch. The gold standard for core temp measurement is a catheter in the pulmonary artery, but most people in sports science settle for a rectal probe or a swallowed capsule with a wireless transducer. A core temp of 100º during exercise is of no concern: you can get to that temperature easily during hard exercise in the cold. Elite athletes in hot distance events routinely get up in the 103-104º range and are fine, although this is not necessarily safe for the rest of us. 104º happens to be the core temperature threshold for diagnosing heatstroke.

OldsCOOL

Being on levothyroxin for thyroid multiplies heat effect to me. The other day (my previous post) I overheated on the hills. I love hot weather and humidity as well but when doing hills, it came on quick. Water wont help, brief rest doesnt help and pulse rate tops out. Heat is NOT part of my training. Let’s talk winter. I’ll ride when it’s near blizzard conditions as well as icefishing all winter. I’m not in hot weather southern climates. That also has a factor in it.

rsbob 

In my 30s I loved riding on hot days. I would sweat like crazy which had a nice cooling effect - except for sweat in the eyes.

In my sunset 60s, the heat is no longer my friend. I cannot put out the same amount of effort (this is compared to cool days - not aging) and just don’t feel as snappy. Last year it was 95 and I was doing a quick 30 miles. This ride was after doing several acclimation rides, where my Garmin dutifully kept telling me how acclimated I should be. I stopped in the sun to take a picture and All of a sudden I had a tremendous feeling of vertigo and had to sit down as everything was spinning. Drank the last 1/2 a bottle of water and sat for about 10 minutes until the vertigo was pretty much resolved. I was a bit nervous getting back on the bike for last two miles, but made it fine. When home, I drank lots of water and some electrolytes.

In the future I will drink far more, not push for PRs, and take shady breaks.

50PlusCycling

My hottest rides were in the Everglades in August. No hills, but lots of heat and ridiculous humidity. I sweated so much that I had salt crystals forming on my shins, and my black shorts turned grey with salt. So long as I kept moving, all was good, but whenever I attempted to stop, and the air stopped moving over my body, I would get a little dizzy from heat exhaustion. Having been a medic in the Army, I have seen lots of people collapse from heat exhaustion the moment they stop running, marching, or whatever, so I had to keep going. I don’t recommend riding alone in hot and humid conditions.

Hermes

Pre pandemic, I belonged to a gym that had a sauna and next to the gym was a cryotherapy lab. I did the cryotherapy for about a year with the idea of getting better recovery. The protocol was 3 minutes in the tank with nitrogen at minus 200 degrees F. A number of pro athletes were using this technique at the time - LeBron James and the AG2R pro cycling team to name a couple. It seemed to stop inflammation and felt great after if was over. However, inflammation is needed to get stronger so therapy like most other strategies have to be used when appropriate. I tried going right from the sauna to the cold tank. it was okay but I did not see any difference per se.

I worked for a Finnish company and was in Helsinki a lot. The Finns are capable of many interesting things and sauna behaviors are unique.

terrymorse 

Yeah, about that cryotherapy thing. Other than feeling good, there's very little scientific evidence that cryotherapy does anything at all:

"In 2016, the FDA put out a consumer warning that there is very little evidence about cryotherapy’s supposed benefits or its effectiveness in treating the conditions for which it is being promoted, which include not just exercise recovery, but also arthritis, multiple sclerosis, fibromyalgia, Alzheimer’s, and chronic pain. The FDA also made clear that the safety of using cryotherapy has not yet been established. “ A 2015 Cochrane review examined the science on whole body cryotherapy and found that the existing studies were all of low quality, because there’s no convincing placebo, and some of the claimed benefits, like soreness, lack an objective measure and are susceptible to the placebo effect."

Excerpt From Good to Go: What the Athlete in All of Us Can Learn from the Strange Science of Recovery, Christie Aschwanden,

MoAlpha

My daughter is at a meeting in Norway and literally just texted me pics from someone's house where she went for dinner and a dip in the fjord. She said the water was 38º F and five of six people went in. Nope nope nope nope nope.

Calsun

Some of the body's sweat glands shut down when not needed for cooling and there is a period of days to acclimate and get them back to 100%. But as with the OP if one is going up a hill the rider is exerting more than on a flat section and getting less cooling with the much slower speed of the bike. On long trips I would plan to hit a step grade as early in the day as possible and before the pavement had soaked a lot of solar radiation.

In really hot situations I do not rely on sweating alone and will pour water over my head to help cool down. An old trick of pro racers was to soak a piece of cabbage and then put it under their hats. But I rely on getting my hair soaked and then putting my helmet back on. At least helmets have come a very long way in allowing air flow. With the original Bell helmet I quickly stopped wearing it as it made my head a lot hotter on uphill climbs with the loss of airflow over my head.

terrymorse 

It’s the first hot day of the year, and it feels like all my fitness is gone. I abandoned the climbing route and am sticking to a flat course.

Taking a break at Starbucks. The Garmin on the table, in the shade, reads 89.9 F.

Do. Not. Like.