There are many different fabrics available to make athletic apparel. Choosing the suitable material for your needs can help you feel comfortable and confident during your workout.
Look for tanks made with breathable, sweat-wicking fabric, DeRienzo says. This will keep you feeling more relaxed and comfortable than garb made with cotton.
Cotton
Cotton is a soft, comfortable fiber that can work well for low-intensity workouts. However, it could be better for activities where you will likely sweat a lot. Cotton absorbs sweat and can leave you feeling wet and weighed down, which can hamper your performance. If you plan to work up a sweat, choose apparel made with breathable, moisture-wicking fabric such as polyester blends.
Cotton consists of the cotton plant’s seed and is produced by a flowering plant of the gossypium family. The plant’s long, thin, cellulose fibers grow from a tube-like structure extending from the top to the ground. The fibers are then harvested by hand or machine and bundled into bales. Cotton fibers are white or colored, depending on the variety and processing methods.
When choosing joggers, sweatpants, and track pants, look for the Seal of Cotton mark to ensure you buy high-quality, cotton-based products free from fillers and synthetics. You should also pay attention to the athletic material and how the fabric feels against your skin. If it’s scratchy or uncomfortable, move on to another option.
Regarding the fit of these types of clothing, Leavell recommends erring on the side of a slightly roomier fit — but not too much. The fabric should feel comfortable and move with you but not be so loose that it’s distracting or could catch on equipment.
Polyester
Polyester is the workhorse of fitness fabrics, used in everything from tanks and tees to sweatpants and shorts. It’s a durable, wrinkle-resistant fabric that absorbs moisture well and moves it away from the body, keeping you cool and dry. It’s also an excellent insulator, so you’ll find it in cold-weather workout wear.
The downside to polyester is that it tends to foster fungus and bacteria growth and hold onto odors, so it’s best to wash your workout clothes soon after breaking a sweat. Choosing polyester fabrics with a more natural feel (like modal, tencel, or bamboo) can help minimize this issue.
You’ll also see polyester blended with other fabrics, including cotton and silk. For instance, a polyester-spandex blend is trendy for activewear because it’s soft and stretchy but still durable and moisture-wicking. It’s also resistant to shrinking and fading when properly cared for (read the garment’s washing instructions).
If you exercise outdoors in inclement weather, consider polyester-based outerwear materials like Gore-tex. This synthetic membrane coats other fabrics, making them waterproof and wind-resistant while allowing the skin to breathe and insulate, explains certified personal trainer Nadia Ruiz.
Merino Wool
Merino wool is the gold standard of base layers, offering a super soft next-to-skin feel and incredible temperature regulation. Its moisture-wicking ability sets it apart, transferring sweat away from the skin where it can cool you down while still keeping you warm. But it’s costly. A pair of long-sleeve merino tops might cost as much as a solid synthetic layer, including socks and underwear.
It’s also much more expensive to produce, with sheep ranchers, shearers, and processors involved. That’s in addition to the scouring, spinning, dyeing, sewing, and shipping that goes into the garments. It adds up—especially since a single Merino piece might replace many synthetic tops that would have otherwise worn out when you need them for your next hike.
Aside from the price tag, there are some ethical concerns with Merino. One is the practice of mulesing, which involves shearing off large swaths of skin and flesh from the area around a sheep’s anus. While many merino wool producers have ditched this unnatural process to favor other flystrike prevention techniques, it’s still something to remember when choosing merino products.
Another is the fact that Merino tends to smell more than other materials, even after you’ve been sweating for hours. That’s why most people go for a merino/synthetic blend instead. Luckily, many brands use TENCEL Lyocell—a fiber made from the pulp of eucalyptus trees—to help reduce that stink and make their garments more environmentally friendly.
Bamboo
Bamboo is a renewable plant that’s highly versatile and proliferates, so it’s an excellent choice for athletic wear. It is moisture-wicking, odor-resistant, and temperature-regulating. Unlike most other fibers, bamboo is also incredibly soft and gentle on the skin. Currently, most bamboo products are marketed as viscose rayon, made from dissolved cellulose extracted from the plant. This process removes many of the natural properties of bamboo, making it identical to rayon from other cellulose sources.
While bamboo is most often associated with tropical forests, it thrives in a wide range of climates. It is a critical species in rainforest reforestation, and it can be planted to help reduce erosion and build soils that are more resilient to climate change.
The most common type of bamboo is the running bamboo, which spreads through underground rhizomes to form new plants. The rhizomes can be very aggressive or stay in place for long periods, depending on the species and environmental conditions.
Bamboo is an essential source of food and fuel in tropical and subtropical regions but has numerous other uses. Traditionally, it has been used in building and construction, and it can be easily crafted into furniture or tools. Moreover, bamboo is very durable and robust. It can withstand heavy loads without breaking and support structures that would otherwise be too large to be constructed from other materials.
