I’m A PT – Sweating During Exercise Doesn’t Mean What You Think

Yesterday, I left my weekly spin class ― with its lovely dim lighting ― only to feel a hand on my bicep seconds after facing the bright lights of the gym.

A fellow cycle class member wanted to know if I was alright, which confused me until I spotted my scarlet, sweat-drenched face and slicked hair in a mirror.

Still, I told myself, my embarrassing appearance was worth it. After all, the more you sweat, the better the workout ― right?

Well, according to Nuffield Health’s personal training lead, Sam Quinn, apparently not.

“There is a common myth around sweating being an indicator of intensity, but this isn’t always the case,” he told HuffPost UK.

So what does sweating during a workout really mean?

Sam explains that all sweat really means is that your body needs to cool down.

That could be because you’re working your body hard, thus bringing your core temperature up ― but the amount you perspire is “dependent on the individual and isn’t an indicator of how hard you are working or how intense your workout is.”

Clothing, environment, medical conditions (like diabetes and hypothyroidism), body composition, cardiovascular fitness, and genes can all affect how sodden our T-shirts get after the end of our sessions, the personal trainer explains.

So, Sam shared, “Sweating is not an indicator of how hard you are working or how effective your workout is.”

Instead, he recommends gauging how hard we’ve gon in the gym using other metrics.

“Measuring heart rate, VO2 max and tracking your workouts which are proven methods of measuring the efficiency and intensity” of your exercise.

What if I don’t sweat at all during a workout?

If you usually leave the gym without much perspiration, that might not be a sign of anything unusual ― you could just naturally sweat less. 

But physical therapist John Gallucci told Healthline that sometimes, a bone-dry armpit after an intense session can reveal dehydration.

“Dehydration before a workout means that your body will be severely lacking in fluids. And since sweat is primarily composed of water, not having enough of it may mean that your body is unable to sweat,” he told the publication.

Still, if you know you drink enough fluids and still don’t break much of a sweat during a workout, fear not ― your intensity might not necessarily need to change.

And for those of us who could fill a bathtub by wringing out our post-workout gym ’fit, sorry, but apparently that doesn’t mean we’re necessarily doing the class any better (sigh).