Workouts are uncomfortable enough; you don't need extra irritation from your apparel. That's why fabric matters more than you think. The common approach to gym clothes is to look for something breathable, moisture-wicking, odor-resistant, and soft enough that it won’t chafe. But, as it turns out, a fancy and comfy material that fits the bill and looks great can come with a hefty price tag.
“I can’t say it’s a one-size-fits all situation,” says Jessica Krant, MD, a dermatologist at the Art of Dermatology in New York. Some people, she explains, are sensitive to the chemicals in synthetic fabrics; others will get chafing and rashes from wearing sweat-soaked cotton — and both can make your skin vulnerable to breakout-causing bacteria, she explains.
The safest bet, particularly if you have sensitive skin, is to go for something super-natural and moisture-resistant. “Natural materials like wool and silk are more breathable than synthetics, and many are woven with moisture-wicking properties, which can definitely reduce sweat buildup, compared to cotton,” Dr. Krant says. So, while that college T-shirt may look okay, you do want to spend money on apparel that's made specifically for you to sweat — not tailgate — in.
The ideal fabric for sweating in should be something “hydrophobic,” according to Yiqi Yang, PhD, professor of textile science at the University of Nebraska-Lincoln. Hydrophobic fabrics have a tighter weave or an invisible barrier that makes moisture roll off. Synthetic fibers are often treated with chemicals that make them hydrophobic, but materials like wool and silk have moisture-repellant qualities naturally. Cotton and linen — the other two natural-fabric options — are easily drenched with moisture, which is why wearing a cotton tank can leave you feeling downright soggy after a workout.
The other perk of hydrophobic fabrics is that they tend to do better with temperature regulation, helping you feel cool during your workout, but not too chilled when you finish. That’s not to say you should throw on a wool sweater the next time you go for a sprint. Dr. Yang notes that not all fabrics are made alike; the wool woven into your favorite sweater won’t be optimal for a pair of running pants. Instead, look for merino wool (also called “performance wool”), which is a smaller fiber and therefore ultra-soft. It, like most wools, also has natural antibacterial properties.
Other materials can have anti-microbials woven into their fabrics for “anti-stink” properties; silver nanoparticals, for example, are surging in popularity. Athleta weaves silver salts into some of its fabric, helping you stay fresh and allowing you to wash your workout gear less frequently. Dr. Yang agrees that antimicrobial textiles can do wonders for reducing sweat stink, but it's always important to keep in mind that they’re a non-natural fabric.
Each fitness retailer has its own version of fresh-smelling, water-wicking, durable, comfortable fabric. GapFit's signature performance fabric is made of 88% nylon and 12% spandex; it wicks water away to keep you dry. Lululemon’s signature luon fabric bills itself as soft, stretchable, and sweat-resistant, with a super-soft feel — and there are four levels of the fabric available.
But, the fabric is only part of the equation. Additional design features such as seamlessness (to reduce chafing), thumbholes (to prevent sleeves from riding up), and strategically-placed pockets (so you can stash essentials during your workout) also make apparel more functional and more costly. Find what's most important to you — and your workout — and shop accordingly.
Recently, a friend of mine (who always seems to leave the gym looking immaculate), mentioned her secret for staying so fresh during exercise: Her athletic wear is made of silk. It all seemed very Kate Middleton-esque to me, but I thought maybe she had a point. I asked Dr. Krant what she thought about some of the new materials on the market: performance wool; athletic silk; and Qsilk, a material made by German manufacturers from sour milk proteins. She gave a thumbs-up to the first two but seemed wary of the idea of lactose leggings. “They sound delicious to eat, but more scientific evidence is needed [to prove] that they make a difference in any given skin condition.”
With Dr. Krant's blessing, I decided to try a silk sports bra from SilkAthlete, the company that makes the silky apparel my friend wears. The material used is 50% silk and 50% nylon. The fabric felt impossibly smooth, like something I’d wear as lingerie rather than on a jog. But, as soon as I started moving, I completely forgot that I was wearing it — and it stayed dry for my entire run. I wouldn’t go so far as to say that I smelled like a daisy after my workout, but it kept me feeling cool and comfortable the whole time. And that feeling, friends, is priceless.