I am a heavy sweater (4 pounds water per hour on a hot day) and am always fighting sweat in my eyes. I've tried about everything out there and can deal with it, but on a long ride on a hot day there will almost always be an occasional problem.

When I watch coverage of the TdF, Giro, etc. these guys are often riding in very hot weather but I NEVER see them obviously fighting sweat in their eyes. What is their magic secret? Is it simply that their faster pace and stronger 'artificial breeze' mitigates that (plus some serious drafting)? When I go out for a solo 2'ish hour ride with a serious, but not maximal effort, I will probably average at least 19 mph. So I'm not lazing around (but not climbing at 19 mph either).

But I almost never see these guys wiping sweat from their eyes (that I remember) and I don't recall seeing all kinds of headband, skull cap, sweat gutter, etc. crap under their helmets.

dave

Bike position. A bigger drop to the bars tends to channel the sweat down your nose instead of in your eyes. Keep in mind that when you are mostly skin and bones, you can get chilled at 85(f) degrees. I have noticed some riders fighting the sweat on climbs, Greipel for one (not entirely skin and bones), but those are also the riders who tend to get very little camera time outside of sprints.

I live in an area that is very hot and on group rides I see others drenched in sweat but I am not. I think genetics has a lot of influence here.

I'm mostly skin and bones, and I have a hard time getting chilled when it's in the 70s. I'm miserable and sweaty sitting still at 85+. As @robabeatle said, genetics has a lot to do with how much one sweats; especially when things like being overweight aren't a factor.

I have often noticed that immediately after the race, there would be the interviews with microphone and camera right near the finish line. I cannot remember any time that the rider did not take off his helmet. Its always on. To me it would be counter intuitive. I would get off the bike and take the helmet off.

May have more to do with contractual agreements with the equipment sponsors. I'd want to be out of the helmet, shoes and clothes instantly.

Pro riders are less prone to having problems with salt in their eyes because they're careful to stay hydrated. If your sweat is salty enough to burn in your eyes, increase the amount of water you drink per hour.

Depends on many factors but your location isn't known for low humidity. A lot of the tough finishes in the tour happen on mountain tops where temps areen't as high. On the flatter finishes where it might be hotter they're not working as hard. Being close to 2lb per inch of height also helps significantly. Lighter riders have a disproportionately high surface area to weight ratio compared to heavier riders so managing heat is easier for lighter riders. And genetics clearly play a role as well. At 165lbs I'm not a lightweight but never have a problem with sweat in my eyes while riding. I might notice it when I stop but not when riding.

I've never seen that discussed. FWIW, here is a study (and I have no way of knowing if it is of value or not) that shows a 'heavy sweater' exercising for two hours with no fluid replacement, and his basic sodium balance changes by around 3.5%. But maybe the quoted statement is correct. I've simply never heard of it being a significant factor before.

dave

ps. Oops - left out the link https://sportsscientists.com/2007/11/...-electrolytes/

I doubt that. Putting aside my disbelief about the percentage of sodium in your sweat based on hydration, after hours of sweating and drying in the wind there is going to be some salt build up on the skin, and thus the potential for concentrated salt to end up somewhere. I still think it comes down to bike position. I'm a profuse sweater with a fairly large drop to the bars, and 2-3 liters an hour on a hot day is not at all unusual. I don't ever remember the sweat getting in my eyes on the bike unless I stop and sit up. It drips off the front of my helmet (the liner wicks it up and releases it at the lowest point), any remainder drips of my nose. When doing anything else in hot weather I'm constantly using my finger as a squeegee to clear my forehead, else it would most definitely end up in my eyes.

I agree with the comments about position on the bike. Back when I was racing and also doing endurance events, I don't recall having to wipe sweat out of my eyes or face that much. Perhaps somewhat on a long climb on a hot day, but other than that it wasn't a huge issue.

I'm also a competitive horse rider and am almost always in a very upright position. With horse riding, I do find that I'm constantly wiping sweat off my face because otherwise it goes into my eyes.

I read somewhere that they put vaseoline on their eyebrows. It channels the sweat around the eyes, it makes a dam that the sweat can't go over.

Another factor is humidity, note current dew points:

Pinehurst, NC 69 °F
Paris, France 57 °F
Alpe D'Huez, France 52 °F
Salt Lake City, UT 45 °F

Living in the mid-Atlantic myself I know that 69 is about as good as it gets in the summer, 75 is typical. So this year in the TDF when riders were complaining about the heat, it was a little warm, but for someone from this area, 90 degrees with a 57 degree dew point would feel more like late October.

I've thought about this a lot as a huge sweater who's thinking about quitting cycling outdoors due to sweat (chamois chafing, spraying sweat on others, etc.). I'm a sprightly 75kg in pretty good fitness but have a really high normal body temperature.

I think the extra airflow from their speed has something to due with it, but that doesn't explain on climbs. I'm amazed how their hair is completely dry during/right after rides while mine is soaked.

Agree with everyone regarding genetics , maybe pros got more into cycling partly due to their low sweat genes?

Bird bones, as evidenced by the absurdly low body weights and many broken bones every time they touch the ground.

I've always suspected that the pros have very little in the way of anaerobic metabolism. Being nearly 100% dependent on the anaerobic side myself, I sweat like a pig, even if it's cold. Most everyone I've known who is exceptional at endurance stuff seems to hardly sweat. Maybe aerobic energy produces less heat? Sweat gene theory would fail if everyone produces the same amount of heat from the same amount of energy output. You have to keep cool somehow, and I don't see any other heat dissipation mechanism that is unique to birds, err pros.

I am definitely an aerobic kind of guy. At age 66 cycling results are harder to evaluate but in my 30's I was running 2:40'ish marathons and couldn't sprint my way out of a wet paper bag. And I sweat 4 pounds/hour on a routine basis and can go higher on occasion.

Alberto Salazar (definitely an endurance kind of guy) had a documented sweat rate max (while training for the 1984 Summer Olympics) of 7.8 pounds per hour.

I think the aerobic guys can be the same kind of sweat hogs as the anaerobic guys.

dave

Guess that blows the metabolism theory, unless it's related to metabolic rate and not dominant metabolic mechanism. Most studies suggest that it's linear relationship to body surface area...

Sweat Rates and Fluid Turnover in Professional Football Players: A Comparison of National Football League Linemen and Backs

But if it's not a linear relationship between surface area and sweat rate, wouldn't too much sweat result in a lower body temperature for the heavy sweaters? Or at least they should have an advantage at lower humidity compared to light sweaters (personally, high heat is trivial to me compared to high dew points). Absent in all the studies I can find is a consideration of relative humidity, which may affect different body types and metabolism's in different ways depending on the conditions.

Tie a bandanna over your head, pirate style, but fold the lower section over twice or so, so that there is an outer lip around your forehead. Put your helmet over this, or don't wear a helmet so the sweat will evaporate faster. This works fine for me; I sweat a *lot*.

(If you can wet the bandanna with cold water before putting it on - it's really nice.)

I've always wondered the same thing. I've tried everything out there, with the SweatHawg skull cap being the only thing to end up working well. Regardless, it just delays the inevitable. And while I'm out searching for new ideas to try to keep the sweat out, my riding buddies ride along peacefully. Anyway, the point is, I'm right there with you!

I noticed it more when mountain bike racing, so the position argument could hold some weight there. But I also spent more hours racing off-road, so naturally I'd deal with more sweat there.

I just try to deal with it!