1. CYSTIC BODY ACNE
"Acne is caused from clogged pores with oil, dead skin cells, and other gunk," explains dermatologist Dendy Engelman, MD. "Sweating not only doesn't clean out pores, it attracts dust and dirt. Elements stick to the body more when it's wet and, as a result, accumulate to cause a breakout."
That bacteria doesn't just stick around in the spots where you sweat most. "If you've ever left the gym with a red eye or woken up with a swollen eye the next day and wondered how you got it, it is possible that the gym and your clothes has transferred bacteria into your eye," says Dr. Engelman. Shudder.
3. BACTERIAL INFECTIONS
"Not removing wet and warm clothes gives bacteria the opportunity to spread and flourish on the body," warns Dr. Engelman. And your gym is full of bacteria. "Not only can you introduce new bacteria to your body by touching weights, treadmills, and lockers at the gym, keeping those clothes on allows those bacteria to grow. This increases your risk of an infections, such as staph, which can be dangerous if you have an open injury."
4. FUNGAL INFECTIONS
Staying in damp clothes can also encourage fungal infections, says Dr. Engelman. "Like bacterial infections, fungus infections can easily be caused by not protecting your body and controlling its environment, such as staying in damp clothes. When the protective barrier of the body is compromised, it allows overgrowth, like yeast infections."
Physician Monya De, MD, agrees that showering ASAP — or, in a pinch, using body wipes — is a must. "I had a patient who had a fungal infection in the shape of her sports bra! She would commute home or go get dinner after working out instead of showering," Dr. De says.
5. A LINGERING SMELL
Brunch after Bikram? Not so fast. "Super sweaty areas, like armpits, are a major breeding ground for bacteria on the skin and in the hair follicles," says dermatologist Tsippora Shainhouse, MD. This odor transfers to your sweaty clothing, so if you head out in your tight, wet, synthetic material gym clothes, your scent will hang around all day, even if they eventually dry." No one wants to be that girl.
6. GROSS SNEAKERS
Don't forget to change your socks and shoes too, or your favorite Boosts (and you) may be in for an unpleasant surprise. "Bacteria and fungus love to live in warm, wet environments," says Dr. Shainhouse. "Moreover, the bacteria and fungus can persist in those shoes, which can leave sneakers super smelly, even after you haven't worn them for a couple of days." If the scent isn't budging even when you change out of your gym sneakers right away, she recommends spraying them with antibacterial and antifungal sprays.
7. INFLAMED HAIR FOLLICLES
Spotting spots on your butt? Blame your leggings. Folliculitis, aka acne-type lesions caused by inflammation and irritation of the hair follicles, can pop up on your back, shoulders, and butt when you hang around in sweaty gym clothes and rub up on gym equipment that's covered with bacteria and yeast, says Dr. Shainhouse.