Has anyone seen a reliable guide for handling heat on the run or bike? I’ve got questions and I’ve heard a few answers but I’ve never seen any research or anyone authoritatively answering these questions. I’m not talking about the tips like ice in pantyhose and in all your pockets and slow your pace, etc.
For example:
Long sleeves or no sleeves?Does clothing color matter?Hat or no hat?Do fabrics like SkinCooler work in high humidity?
I do have one answer to share. This pace calculator seems to work well. Of course, Dr. Harrison has already shared the answers for nutrition and hydration.
Putting ice on very small parts of your body does next to nothing to really cool you down. Not enough surface area covered for not enough time. You might briefly “feel” better and cooler but it’s doing nothing to cool your core temp and more placebo than anything.
SkinCooler fabric doesn’t work well in very humid conditions. I’ve spent the last 20-something years living in the Gulf Coast of Texas and Florida. Some of the most humid places in the US. I have thousands of hours running and cycling wearing SkinCooler stuff in these conditions. I’ve also worn SkinCooler stuff in low humidity places like Colorado, Vegas, Phoenix, and Whistler and always go “Oh! This is what it’s supposed to feel like.” You don’t get much of an evaporative cooling effect in humid environments because you’re always wet and only get wetter.
Putting anything over your skin and head is likely to make you hotter as far as trapping heat and breathability. So long sleeves and hats will be “hotter.” The other part of the battle is getting beatdown by the sun. I always wear a hat and mostly wear long sleeves because a) the sun is soul crushingly hot and b) it’s not good for you. Covering up causes less skin cancer and sunburns.
The most important thing you can do in the heat and humidity is stay hydrated and slow down, especially if you’re not used to it.
Nope, not in my experience anyway. I’ve had the desoto and other brands, but they do nothing. In all fairness, the dew point in Houston is in the high 70’s when I have tried them.
The TrainerRoad guys have a number of podcasts dedicated to heat.
Granted since those podcasts have come out I think there’s been some new evidence that would make one reconsider some of their ideas. Like they were promoting the idea that heat acclimitization training can benefit you even if the race isn’t hot. E.g. that we should all jump in saunas after our trainer workouts as a general performance enhancement technique.
I believe the paper that initially made that claim has been pushed back on. Though I don’t have definitive references to link to, nor am I 100% sure.
Overall the podcasts are good instruction, though.
Nope, not in my experience anyway. I’ve had the desoto and other brands, but they do nothing. In all fairness, the dew point in Houston is in the high 70’s when I have tried them.
I tried them (arms and legs) in the Anza Borrego desert for a race and had the worst heat exhaustion I’ve ever had. At one point realized I was a danger to myself on the bike and had to stop and sit under a tree for 20 minutes. I tore them off and continued, and was fine after that.
I’m usually pretty good in heat. And that wasn’t very humid. I wasn’t wetting them regularly, being more focused on racing.
Unscientific anecdote. Could have been totally unrelated to the SkinCoolers. Just my one experience with them.
Just ran at heat index of 102. Gulf coast 3 hours after rain.
Wear a hat with ice, it’ll slow release water to cool you (Headsweats brand is good). Ice will last 25 minutes. Then take hat off so you don’t have boiling water caught under the hat. Then head home. You’ll be overheating soon.
One cannot buy a Skin Cooler product, go out to Anza Borrego Desert (my testing ground) and expect to be perfectly comfortable and stay cool. Just like any other product you buy for endurance sports, there is a certain “getting-use-to” that is required. Such as wearing it on shorter, cooler rides and runs, sweating in it, wetting it, just determining the best personal approach to achieve the ultimate in cooling. This also applies to wearing Skin Cool in high humidity. When there is high humitidy, there is no evaporation. At that point what is important is not whether you are wet or dry, but whether you are cooler and more comfortable than you would be if you did not have the Skin Cooler piece.
I may or may not have done extensive research on this (and many other conditions) while leading innovation for a major cycling apparel manufacturer…
These results are for “average cyclists, riding at 175w, with representative wind speeds, radiant load, in both hot / dry and hot / humid conditions” unless otherwise noted
The quick and dirty
Color - theoretically lighter colors are cooler than darker, yet darker tends to block more radiant heating of the skin directly. I did not see a statistical different between color options including a light outer and dark inner face (which is why that blue is kinda a funky color)
Baselayers - Because they increase the distance from the skin of the evaporation, the evaporative power is significantly lower, cooling is less and riders are warmer.
Sleeves - In general sleeves are warmer for the same reason as above - you are not evaporating from the skin you are evaporating from a layer above the skin which removes less heat. Now, if you are constantly wetting the material, then you can likely improve cooling over dry skin. However, the sleeves need to be constantly wet or the effect is lost. Personally, I will wear sleeves on some longer rides purely for sun-protection, not to maximize cooling.
Material - In hot-dry conditions both “stretch-wovens” and “meshes” work well. However, in hot-humid conditions the more “meshy” the material the better. I think this is because evaporation is compromised in high-humid conditions, so it is important to evaporate as much from the skin as possible.
During the first “commercials” portion of his podcast on Saturday, in the midst of reading his prepared ad copy for LMNT, Lance went off-script and used the term “projectile sweating” - which I would imagine a scenario in which sweat is pouring out of you in such volume as if you’re a sprinkler, to the dismay of people behind you on a run or bike (George, in this case)
This phrase has been welcomed and fully adopted by the MartHousehold
Considering the variety you see at Badwater - long shorts, short shorts, tight shorts, baggy shorts, Keith Straw’s pink tutu - there may not be one definitive answer there
.
I honestly think that temperature calculator is one of the best resources out there. You can’t overcome bad pacing in bad weather. It’s tough to put in a ton of training & have to put your ego aside & make a pace adjustment in bad conditions but if you don’t do that you’ll go backwards much quicker than if you made the adjustment.
I think everything else you asked is just about using common sense/trying to stay as cool as possible. If it’s a scorcher & a short distance race then why not go sleeveless. Sleeves are still going to be faster for longer races & a lot of the higher end suits are designed to cool you down so that’s not going to have much of an impact. Wear lighter colors, if possible. Hats are good/bad – they can trap heat so that’s why you see more & more of the cooling headbands or visors or no hats.
Fueling is my addition when talking about racing in the heat. Important to fuel early & calculate additional losses.
Hats are good/bad – they can trap heat so that’s why you see more & more of the cooling headbands or visors or no hats.
I’m at an age where the snow on the roof is getting a little thin, so whenever I’m outdoors for an extended period of time, I gotta cover the noggin or risk some sunburn up there - which is never pleasant
I know that there exist sunscreens specifically formulated for such an application, but I’ve never had much success with that
Was there any difference in tight running shorts versus baggy, in regards to heat dissipation?
Not something that I’ve personally tested, however, I can extrapolate my knowledge to say that if moving heat is important then direct contact of skin and air is beneficial.
Therefore, I’d go baggies for cooling purposes over longer “spandex” shorts. Convective, evaporative, and radiant losses should all be higher.
I had extrapolated that same conclusion from your original post.
I suppose it’s a trade off on “coolness”, actual cooling and weight (when baggy shorts get wet they feel a lot heavier than the tight shorts - which probably can’t hold as much sweat).
If you use enough sun screen, it looks like running naked would be the coolest - although none of my neighbors want to see me naked and I don’t want to see any of my neighbors naked
Check out “The Real Science of Sport” podcast. Hosted by renowned Professor Ross Tucker. The last few episodes (maybe before that) address this issue and provide a ton of insight.
The podcasts are always well referenced with links and studies etc etc
