Outside of a barre class at a boutique studio in New York City, over the Thanksgiving holiday weekend, a woman who had just purchased a new pair of yoga pants after class was heard saying, "I'm just gonna change into this now, because if I go home to shower, I won't go out again."

Maybe not the best idea.

The sentiment is a familiar one, given the rise of "athleisure" — a phenomenon so popular that the next edition of the Merriam-Webster Dictionary will include it as a term. But there can be danger lurking in your yoga pants and other workout clothes, if you decide to keep them on too long. And we know that the signature athleisure move is to do just that: Wear your exercise gear as long as possible.

Yeast infections, zits and rashes, oh my: Dr. Michael Eidelman, the medical director of Chelsea Skin & Laser and assistant professor of medicine at Mount Sinai School of Medicine, told Mic that there are a variety of skin issues that can pop up thanks to clothes that "don't breathe as well and hold sweat closer to the skin," thereby creating "so much warmth and moisture."

One big concern, Eidelman said, is folliculitis, an inflammation of the hair follicle that can come from damage or blocking of the follicles, thanks to tight clothes or rubbing. Folliculitis on the upper back is common for women thanks to sports bras, noted Dr. Elizabeth Hale, a dermatologist and medical professor at New York University, on the Dr. Oz blog. But any extended friction can create a risk, like spinning, which Eidelman said can cause folliculitis on your butt (all the more reason not to stay "in the saddle" during your next SoulCycle session).

Buzzfed

As for lingering moisture, flare-ups from the growth of fungus and yeast is a big concern. Tinea cruris, also known as jock itch, is a fungal infection that affects the skin of your inner thighs, butt and genitals. Eidelman said it is more common in men but can occur in women as well.

More common for women is vaginitis and yeast infections, which often come from wearing tight, moist clothing for too long. According to Eidelman, this is a greater risk if a person is on antibiotics for, say, acne.

Another kind of inflammation is intertrigo, a rash that Eidelman said pops up in the folds of the body in moist environments — such as the inner thigh, butt crease, armpits and that beloved underboob region — that makes your skin raw and irritated. And don't forget good old acne, which can flare up on the back and chest from the trapping of sweat and oil, Eidelman told Mic.

Not just what you wear, but where you are: As the founder of fitness site MizzFit.com, Bianca Jade works out constantly, so she knows just how gross gyms and workout studios can get, thanks to "people coming in, sweating, leaving in high numbers," she told Mic.

That can mean the transfer of sweat, which is how Jade believes she got dyshidrotic eczema on her sensitive skin, thanks to a previously used yoga mat. Dyshidrotic eczema can emerge, often on the hands, due to to an excess of moisture. Jade said it made her hands bubble dramatically, and she's seen it with many others regularly involved in fitness.

Dirty, wet gym mats can also exacerbate tinea versicolor, according to Eidelman, which is a fungal infection that shows up as a discoloration of the skin, usually in white patches.

After working out, Jade said, we should think of ourselves as a gym — sweaty, covered in bacteria and in need of a good clean — otherwise we're just "sitting in a pool of your own toxins."

Onsugar

What's a Lululemon-loving exerciser to do? Stacy Lyon is the creator of Healthy HooHoo, which makes wipes and washes for "down there." Lyon told Mic she started her company after a conversation with her gynecologist, who said she was seeing more and more women suffering from vaginitis. The doctor told Lyon that a "perfect storm" was contributing to the rise in infections, including too much processed foods, over-cleansing and wearing tight, synthetic clothing — like thongs and yoga pants.

Getting clean helps. "For work-out babes and yoga divas, it's super important to remove both sweat and bacteria from the vulva aprés class," Lyon told Mic.

More importantly, allowing skin to breathe, "down there" or elsewhere, seems to be the consensus when it comes to preventative care. Some exercisers opt to wear no underwear at all under workout pants, while some companies make yoga pants with breathable underwear built in.

Eidelman agreed that wearing moisture-wicking clothing during a workout is key, as is showering and changing into more breathable clothing afterward.

In other words, as tempting as it is, maybe don't wear that activewear all day. Yoga pants aren't evil, but keeping them on all day can be.

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