Picking up from the https://www.bikeforums.net/commuting/...e-curious.html thread...

I was at a conference with a bunch of doctors last week so was able to talk to a few about this.

About 1-3% of the population experiences hyper-sweating. EG, they sweat more than normal, it is somewhat uncontrollable, and the cause is not well understood. (The OP and [MENTION=21724]cyccommute[/MENTION] perhaps in this group?) They believe that for the vast majority of these it is food related such as too much sodium, fat, processed foods, etc. With these, once understood, it should be controllable through diet. For a few of these, roughly 1/10 of 1% of the population, it is likely genetic and uncontrollable without meds or other intervention. For another similar size 1 in 1,000 group it is thought to be mostly stress/psychological.

For the rest of the population, sweat is normal and largely controllable. The top causes of consistent sweating are being overweight, poor physical fitness, and poor diet. They all noted that sweating is a much greater problem in the US than Europe and Asia due to our food supply (high sodium & preservatives), lower daily activity, and being overweight.

Beyond fitness, diet, and weight they said that moderating activity to stay at or below the heavy sweat threshold, dressing appropriately, and staying hydrated were the keys. They distinguished between light sweat and heavy sweat and noted that even heavy sweat did not necessarily produce any odor in many circumstances. Odor comes from bacteria, not sweat. It is when sweat is trapped and cannot evaporate as it develops that the bacteria and odor develop. Bicycling examples are sweat trapped in helmet hair or folds of belly skin.

Specific to bicycle riding... They confirmed that helmets and gloves will cause considerable sweating, bacteria, and odor. One also mentioned tight fitting shoes. I'll leave their thoughts on helmets to another discussion but they were evenly split 3:3. Any leaning forward will increase sweat, particularly for people who are even slightly overweight. Efficient geometry that allows progress with as little effort as possible was mentioned as were e-bikes.

In theory at least, someone should in most cases be able to ride any distance on a bicycle with less sweat than walking that same distance in the same conditions. The thought being that someone on a bicycle will experience greater cooling per kilojoule of effort. They noted that ambient temp has almost nothing to do with sweating but the dew point does. Their example was playing golf in 95f Arizona can be sweatless while in 80f Hilton Head can be a sweatfest.

The human body...a marvel of engineering, except for when it isn't.

My personal thoughts. I travel a fair bit and ride bicycles in a number of different cities. Most often Twin Cities MN, Marco Island FL, NYC NY, Birmingham AL, Amsterdam NL, and London UK.

It is easier to prevent sweat in Amsterdam than the others. Taking off from the doctors above; Bicycling in The Netherlands is much less stressful than elsewhere, food is healthier and not as high in sodium or chemicals, nobody wears helmets or gloves, efficient upright bicycles are plentiful, there is never a feeling that you must ride faster due to motor traffic, and there are lots of great places to stop for a hydrating beer. Even on hot humid days I think these all play a role.

The other cities aren't usually impossible though. For me anyway.

Sweat is relative. I'll sweat less riding a Citibike at a moderate pace down the Hudson River Greenway on a hot humid day than if I walk the same way. I might still sweat, but less than if I'd walked.

I think bicycling would often be less sweat inducing than taking the subway depending on how long you have to spend in what sweltering station. One day last summer I was fine going in to the subway and on the air conditioned journey but I was drenched walking from the train up to the sidewalk. I don't think this caused much odor though (and I asked my wife, son, and DIL) and that is perhaps due to no opportunity for bacteria since I was not wearing a walking helmet nor was I hunched forward while walking.

How much is the issue sweat vs odor? One goal is to prevent or lessen sweating but odor itself may be a somewhat different goal. In addition to reducing sweating, reduce opportunities for odor producing bacteria to develop?

For the people who say that they are abnormally heavy sweaters, does sweat always produce odor?

As someone who grew up in Arizona and played golf in 95+, it is not sweatless. You sweat A LOT, it just evaporates nearly instantly. It still can cause odors and at a minimum you're left with a light salt crusting.

It's why AZ has major issues with heat stroke and dehydration. People don't hydrate because they don't realize they're sweating.

What is different is your body's cooling rate. Sweating in low humidity is vastly more efficient cooling than high humidity, therefore you need to sweat less for the same effect.

Hurray for the south east - we have hot temps and high humidity! I don't tend to sweat heavily until I've been off the bike for a minute or two, than it's hard to stop for a little while. Just easier to shower at work and change into dry clothes. I may get away with not smelling too bad, but that feeling of being grimy and salty all day sucks

[MENTION=341677]gsa103[/MENTION], great points.

Agree. If I've warmed up I'll go extra slow the last .5 to 1 mile to cool down. Worst though can be below freezing winter days. Same cool down for last bit applies but I'll often take my jacket and hat off outside and stand for a few seconds to a minute before going in to the much warmer and more humid indoor air.

I wonder if sodium intake has any impact on how salty our skin feels after sweating?

I started a thread a few weeks ago about how my bike gloves get disgustingly smelly. I've decided I'll wash them frequently now, every day, if possible. Same with my helmet. I may have to have two pairs of gloves and two helmets and alternate them.

I'm pretty thin so I don't sweat for long after I exert myself. I can shorten the time even further if I wash my face, head, and neck upon arrival at work. The water cools me which cools my blood, which cools my body. Washing clears my pores, allowing me (and my pores?) to breath more easily.

I suppose it is easier to ride gently on an upright bike. I ride Citi Bike (the NYC bike share) at least once a week. Those klunkers put the rider very upright. Now that I think of it, yup, I don't sweat as much on those bikes as I do on my bikes. Not that I want my bike to have upright bars.

Air conditioned subway cars came in the 1980s if I remember right. It made the overall subway riding experience better, but the downside is that the station platforms are intensely hot. The trains spew a lot of heat, and that heats the tunnels as well as the stations. The platforms are hot for weeks after the summer heat is gone because the bedrock retains the heat so well.

I have very often wondered why they don't do a better job of venting the platforms. Besides heat the staleness of the air is not too pleasant. Subways in Europe (and Wash DC?) aren't nearly as bad as NYC even on the hottest and most humid days.

Then there's the issue of walking by or over the vents in the sidewalks. Ugh. Rather fascinating though is 58 Joralemon Street in Brooklyn that looks like a townhouse but is actually a vent and tube access. Seems there are a few of these around NYC.

[MENTION=179437]CrankyOne[/MENTION], do you live in NYC now? Your profile doesn't say.

I'm only guessing but perhaps the problem is harder to solve because the system is so much older than other subway systems. I've been using the subway a lot in the last couple of years, and I've been thinking about how dirty the air feels to my lungs and sinuses. I was thinking they ought to plunge the tunnels with water or steam, because the brake dust just accumulates. Then lo and behold, they just announced that they're going to start cleaning the tunnels more frequently than ever, though I don't know how. So here's hoping. I'm sure this air pollution has an appreciable effect on many people's healths.

Ventilation is a technology, so I imagine it improves over the years, but only if planners pay attention to it. It was one of the major technologies that enabled the Holland Tunnel (under the Hudson River between NJ and NYC) to be built. Without it, the tunnel would have been unusable. It's about 1.6 miles long.

Sounds to me like Male Answer Syndrome, orated by presumably male doctor(s) who haven't ridden a bicycle since, maybe, the summer after their first year in med school. How many of these expert M.D.s have ridden a bike in, say, 80 F in the last 10 years?


Not to mention the cure-all of "eliminate overweight." Somebody stuff a twinkie in that expert's mouth, fast!

Meh. I think that the cure-all might just be that, a cure-most, for Americans at least. Unhealthy response to exercise reflects an unhealthy body for most of the population. Doesn't it?


We're having a "health fair" at my employer at this very moment. Interesting. Lots of things on dental health (super, super important) and diet (equally important), as well as screenings, stress management, exercise, and even cosmetic things. Cool.


Standing back and looking at the crowd, I took away that the average "low hanging fruit" weight loss among my co-workers might be 18-25 easy pounds. With little effort at all. Think of the savings on medications, if we did that across the population! It's mind boggling. Just sayin'...

I took part in the discussion mentioned too and I maintain that the average person doesn't have to sweat commuting.

- It might require a little training, but in Copenhagen the speed of the green wave (synchronized traffic lights) is 20 km/h or 12 mp/h and that is aimed at commuters in their regular clothes.
- It requires attention, if you start sweating you're too late with slowing down. It possible not to heat up too much while averiging 12 mp/h, it not possible to cool down averiging 12 mp/h, or 11, or 10.
- Adjust your clothes to manage body heat while riding, and you can dress for the destination but it's okay to be a bit cold the first 2 minutes of your commute. You don't need to dress for the cold like you're going to sit still in it if you'r going to ride in it.
- Keep momentum, don't do bursts, don't use your opper body and keep a straight line.

In my experience if you're fit you sweat less, if you sweat a lot at other exercise and rehydrate properly your sweat won't be a smelly. Fresh sweat does smell but not bad, old sweat smells bad, and old deoderant that has been 'worked' smells even worse.

Shrug. Doctors, schmockters...what do they know about the real world?

Here's my guide:

On a hot day, I'll drink two liters of water over a 50 mile ride and never pee once. On a day like today, I'll drink one liter and pee like a race horse. Conclusion, very little sweating.

The rest? Who cares? Some people sweat more than others. Wearing gloves and a hat will lead to more sweat. Yeah, that was worth the million dollars spent on the study.

I sweat therefore I am.

I gave up years ago. I don't think I sweat excessively. But in the winters, mild here, I've been cold and still sweating where my backpack lays on my back. I don't see that as a problem. It's just sweat. Wipe down with a damp wash rag, towel off and put on my work clothes.

Trying to ride slower doesn't work here in Phx in the summer. Not for me anyway.

Anytime I see someone commenting about sweating during a commute I have to laugh. Especially if they're from somewhere where they don't have hot or humid weather. Even more so if they're only experienced with flat commuting. Throw in any sort of decent hill and it all falls apart.

Easy to see for yourself, look at the grade for a local hill and then run the numbers through a power calculator to see what the power needed to go a certain speed is. Regardless of weather or attire anytime a hill gets steeper than 1-2% it is impossible to ride up at a pace available on the most common gearing without sweating. Or really a pace faster than walking without sweating. I sweat a lot but I certainly don't think it's excessive. I've never been riding around in the sun sweating and then been like "man I'm am chilled to the bone by all this sweat."

To equate walking with cycling is also disingenuous as they are obviously completely different activities and require different physical inputs to achieve a reasonable moving speed.

What's been your experience with testing this out yourself? Did any of the commentators at the conference have any experience themselves? "In theory" is hilarious when it's something so easy to test for oneself.

Can you elaborate ?

What is the difference between males and females with respect to sweat ? Do females sweat more ? or is it a matter of social acceptance of sweat when dripping from a female vs male forehead ?

Easy there, no need to call in the political correctness police.


Male Answer Syndrome, as far as I know, was discovered by the late Tom Magliazzi on the NPR Car Talk show. It describes the way (some) men, when asked a question they know little to nothing about, come up with a detailed answer which is arbritrarily close to (or far away from) the facts. You really should take a few hours this winter and listen to some of their podcasts that are still online.


Besides, horses sweat, men perspire, and ladies glow!