Join Date: Apr 2006
Location: Brazos River valley, south central TX
Bikes: 2005 Surly LHT; 2006 Surly CrossCheck with Extracycle; 1987 Schwinn World Sport as urban cruiser
Here in central Tx, heat is an incredible impediment to exercising outdoors for many of us. As a kid, I suffered a serious heat stroke (eventually put into a bathtub of ice cubes to lower body temp) and ever since have to watch my participation/activity in hot weather. My physical therapist wife tells me my hypothalomus has been permanently 're-set' due to the heat stroke. My sweat response to exercise or heat is INSTANTANEOUS and for me to re-hydrate means that I drink before, during and after rides. At this time of year I can only ride between 6 - 8 am otherwise the heat makes me sick for hours or even days.
About a decade ago, my backpacking partners & I got lost in an Arizona wilderness for 48 hrs. past when we were to have finished a 5-day hike in rugged backcountry. Search & rescue teams, media helicopters, the whole circus was out looking for us. We hiked out eventually on our own but one partner worried when we left the creekbeds for higher ground that we would run out of water. So he stopped drinking with the thought that when we had emptied our canteens, he would have some to offer us. About three hours before we were found/rescued/made the main trail, he almost fell out because of back pain. We were transferring weight out of his pack into ours and he could barely walk. Turns out his kidneys were starting to shut down from dehydration. That's when we found out he hadn't had anything to drink for over 4 hours in the blazing AZ sun! His doctor later said that the backache was the 1st sign that his hours were numbered...
From that experience I can imagine that kidney tests could reflect dehydration stress but don't know any of the physiological specifics, sorry. (See? I'm trying to return to the original thread topic at the end of my ramblings...)
They're beautiful handsome machines that translate energy into joy.