A new study shows that skipping sleep can impair your body’s ability to cool itself during intense exercise in the heat—especially if you’re over 50.
Researchers from the University of Ottawa had 10 older male participants (average age 61) preform three 30-minute bouts of cycling in a hot, dry environment (40C and 13 per cent humidity). Each participant did the test twice: once after a normal night of sleep and once after 24 hours without sleep.
After the sleepless night, participants had significantly lower peak heat loss during the most intense stage of the workout—about 12 watts per square metre less than when they were well rested. That difference led to increased heat storage in the body, raising the risk of overheating.
While sweat-based cooling wasn’t significantly affected, the study highlights that even one night of sleep deprivation can impair thermoregulation in older adults. Planning a hot-weather workout after a rough night? Consider moving it indoors, lowering the intensity, or better yet, getting some rest first.
Source: Medicine & Science in Sports & Exercise
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