Originally Posted by
erig007
True we usually need to get rid of the excess heat and sweat but it depends among others things on the weather and the kind of activity we are doing.
Around freezing temps i usually like my breathable garments which allow a wider comfortable temperature range but the more the temperature goes down the more I switch to less breathable layers as long as i'm able to protect my insulation layers from moisture. The lower the temperature the closer my system is from a
VB or vacuum-bottle like system as it allows my body to be isolated from the outer environment. At around -30F/-40F for instance even the smallest cold wind burst which goes right through the layers can remove too much heat and lead to hypothermia so most if not all the heat generated by the body (latent heat, sensible heat, no conductive and no convective heat transfer etc..) must be kept inside the system.
That's true. The colder it is, the easier it is to evaporate sweat, so we can use ever thicker and more windproof garments. Fairbanks is a bit of a special case, because it's never windy there in the winter. Biking is a special case, too.
For years I've been using a HRM for all my activities - XC skiing, downhill skiing, cycling, hiking, climbing, weight lifting, etc. It's pretty simple. The higher the HR, the more the need to get rid of heat and moisture. Back in the day, I raced XC at 15° in just a jockstrap, thin cotton knickers and a thin cotton jersey. My privates got cold, but the rest of me was fine. Yes, it was cold on the descents, but it got warm quickly on the flat or climbs. The cotton was OK because it never got wet.
Cycling is next most intense. Then climbing or hiking - I normally don't climb at a HR over 115, while I climb cycling at 140-150 (I'm old). Cold weather climbers dress for the expected conditions, then moderate or increase their effort to stay just below the sweating level. Downhill skiing can get intense, but only for 2 minutes at a time, and those minutes are in high wind conditions, so sweating is never a problem. I've downhill skied at -50 F.
Walking is never a problem, because we never sweat unless we are way overdressed. Delivering papers on foot in Fairbanks, I used to underdress and then jog a bit if I got cold, sort of the same thing as climbing. Wet is the enemy in cold weather. OTOH, riding in the rain, wet is assumed and one dresses for that. One has to experiment to figure out how to dress for conditions. I keep records of what I wore for what conditions. Since I do so many different things, it's easy to get confused or forget.