In the midst of a heat wave, should you wipe away your sweat, or does that just keep you from cooling off?
Don’t wipe unless you’re drenched. Sweat releases heat by evaporative cooling. As each gram of sweat transitions from liquid to gas phase, it absorbs 2,427 joules of energy from the body and dissipates the heat into the environment.
But if you wipe away the perspiration before it evaporates, that process will get cut short, and you’ll need to sweat more just to achieve the same degree of cooling.