Written by Foam Laundry | Salt Lake City's laundry pickup and delivery service.
The single most damaging thing most people do to their workout clothes is add fabric softener. Fabric softener coats synthetic fibers with a waxy residue that permanently blocks moisture-wicking channels. After two or three washes with softener, a $90 Patagonia Capilene base layer performs like a cotton undershirt. It is not recoverable. Skip the softener entirely.
Why Fabric Softener Destroys Athletic Wear
Moisture-wicking works because synthetic fibers (polyester, nylon, spandex) have a hydrophilic surface treatment from the factory that pulls sweat away from your skin and spreads it across the fabric for evaporation. Fabric softener deposits a hydrophobic (water-repelling) coating over that treatment. Water beads on the surface instead of wicking through.
The damage is cumulative. One wash with softener dulls the performance. Several washes can kill it entirely. There is no way to reverse the coating once it has bonded.
This matters in Salt Lake City more than most places. At 4,300 feet with 300 sunny days per year, your base layers are working hard from October ski days to July trail runs. A non-wicking ski base layer is not just uncomfortable. On a cold inversion day in Little Cottonwood Canyon, it is a safety issue.
The Right Way to Wash Workout Clothes
Cold water, always. Cold water protects spandex and lycra. Hot water degrades the elastic fibers and causes permanent loss of compression and fit. A cycling jersey washed warm eventually loses the snug sleeve fit that keeps it from flapping at speed. Wash everything athletic in cold.
Turn it inside out. The inside of athletic wear is where the dirt, sweat, and bacteria actually live. Turning items inside out exposes the inner surface directly to the water and detergent. It also protects the outer print and finish from friction.
Gentle or delicate cycle. High agitation stretches and degrades spandex. Use a gentle cycle or a mesh laundry bag for items with heavy spandex content like cycling jerseys, compression shorts, and hot yoga wear.
Use sport-specific detergent or a small amount of regular detergent. Sport detergents (Hex, Sport Suds, Win) are formulated to break down the type of bacteria and oils in athletic wear without leaving residue. Regular detergent works, but use less than the label says. Excess detergent residue traps bacteria in the fibers and makes the odor problem worse over time, not better.
Air dry whenever possible. Dryer heat is hard on elastic. Spandex and lycra are especially sensitive. Air drying preserves compression and fit longer. For SLC residents drying in winter, the dry indoor air is an advantage. Most athletic wear air dries quickly in a heated home.
Fabric Care Table
| Material | Wash Temp | Cycle | Fabric Softener? | Dry Method | Notes |
|---|---|---|---|---|---|
| Polyester | Cold | Normal or gentle | Never | Air dry or low heat | Most common base for athletic wear; wicks well when clean |
| Spandex / lycra | Cold | Gentle | Never | Air dry only | Heat destroys elastic; never tumble dry on high |
| Nylon | Cold | Gentle | Never | Air dry | Prone to pilling under high agitation |
| Merino wool | Cold | Gentle or hand wash | Never | Flat dry | Felts under heat and agitation; handle gently |
| Fleece / Polartec | Cold | Gentle | Never | Low heat or air dry | Fabric softener collapses the pile; avoid completely |
| Cotton-poly blend | Cold to warm | Normal | Avoid | Low heat | More durable than pure synthetics; can tolerate mild detergent |
| Down jackets | Warm | Gentle, alone | Never | Tumble dry low with tennis balls | Re-loft the fill; always wash alone or with down-safe detergent |
| Compression fabric | Cold | Gentle | Never | Air dry | Compression relies on intact elastane; heat and softener destroy it |
| Chamois / cycling pad | Cold | Gentle | Never | Air dry | Chamois antibacterial treatment breaks down with hot water or softener |
| Climbing chalk fabric | Cold | Normal | Avoid | Air dry or low heat | Pre-rinse to remove loose chalk before washing |
The Odor Problem: Why Workout Clothes Still Smell After Washing
If your athletic wear smells fine when it comes out of the wash but starts smelling again within minutes of wearing, the problem is bacteria living inside the fiber structure, not on the surface.
Synthetic fibers have microscopic grooves and textures that natural bacteria use as attachment points. Regular detergent removes surface dirt but does not always penetrate deep enough to kill the bacteria embedded in the fiber. The bacteria survive the wash cycle, stay dormant while the item is dry, and reactivate immediately when you start sweating again.
The fix is a white vinegar presoak. Add one cup of plain white vinegar to a basin or the drum of your washing machine with cold water. Soak the athletic wear for 30 minutes before running the wash cycle. The acidity of the vinegar kills odor-causing bacteria without damaging synthetic fibers. Do not use more than one cup. Excess vinegar is hard to rinse out and will leave your clothes smelling sour.
For chronic odor problems in specific items, soak overnight in the vinegar solution before washing. Sport-specific detergents also help because they contain enzymes that break down the fats and proteins that bacteria feed on.
Do not use baking soda as a substitute. Baking soda is alkaline and can interfere with synthetic fiber coatings. Stick with white vinegar for athletic wear.
Washing Frequency
Not every item needs washing after every wear.
Wash after every wear: Base layers (direct skin contact), hot yoga wear, cycling jerseys and shorts, sports bras, compression socks, anything soaked in sweat.
Wash every 2 to 3 wears: Outer layers that do not make direct skin contact, trail running jackets, fleece mid-layers worn over a base layer, light hiking pants.
Wash as needed or seasonally: Shell jackets and rain gear. These should be washed when visibly dirty or when DWR (durable water repellent) performance starts declining. Washing technical shells too frequently degrades the DWR coating faster. Once or twice per ski season is typical for an Alta or Brighton shell.
Odor is not a reliable signal for wool. Merino wool has natural antimicrobial properties and genuinely does not smell as quickly as synthetic fibers. It is normal to ski in a Smartwool base layer for several days without washing.
Ski and Outdoor Gear in Salt Lake City
SLC's ski season runs October through late April at resorts like Alta, Brighton, Snowbird, and Park City. That is seven months of regular ski laundry. Most SLC residents who ski seriously are washing base layers weekly at minimum during season.
Merino wool base layers. These are the most valuable and most mishandled items in SLC laundry. A quality merino base layer (Smartwool, Ibex, Icebreaker) costs $80 to $150. Wash in cold water on a gentle cycle. Lay flat to dry. Never put merino in the dryer. The fibers felt permanently and the garment will shrink and stiffen. We see felted merino in SLC laundry constantly. It is always from the dryer.
Fleece mid-layers. Polartec fleece (used in Patagonia, Arc'teryx, and Rab mid-layers) is sensitive to fabric softener. Softener collapses the pile and destroys the loft that insulates. Wash cold on gentle, tumble dry low or air dry. Fleece generates microplastics when washed, so a Guppyfriend washing bag reduces fiber shedding if that is a concern.
Ski socks. Smartwool and Darn Tough ski socks are merino-blend. Same rules as base layers: cold water, gentle, air dry. Do not ball them up when storing. Rolling or laying flat preserves the elastic.
Trail running gear. The Bonneville Shoreline Trail, Millcreek Canyon, and Big Cottonwood trails leave red clay on everything in spring. Pre-rinse trail running clothes to remove loose grit before washing. The mineral particles are abrasive in the wash drum and can damage other items.
Cycling kits. SLC's cycling community (road riders, gravel riders, and mountain bikers on Corner Canyon and Millcreek) knows how quickly a cycling chamois degrades. Wash after every single ride, cold, gentle, air dry. Never use fabric softener on a chamois. The antibacterial treatment that makes it comfortable is destroyed by fabric softener and hot water.
What Foam Sees in SLC Athletic Wear Laundry
We process a substantial volume of SLC athletic wear every week. Three things come up repeatedly:
Fabric softener damage is the most common form of preventable garment degradation we see. We can tell immediately when activewear has been washed with fabric softener. The moisture-wicking finish has a different surface texture and the fabric feels slightly waxy. This is irreversible. If you are currently washing your athletic wear with fabric softener, stop now.
Merino base layers in the dryer. We see felted Smartwool and Icebreaker base layers regularly. Customers bring them in after the damage is done. The felting is permanent. This is entirely avoidable: cold water, gentle cycle, flat dry.
Hot wash on spandex. Spandex and lycra lose elasticity when washed warm repeatedly. Cycling jerseys and compression shorts come in with stretched-out sleeves and waistbands. This is caused by warm or hot water cycles over time. Everything with spandex content needs cold water.
Foam washes all athletic wear in cold water with sport-compatible detergent, no fabric softener, and air dry or low heat for all synthetic items. For SLC residents managing significant amounts of technical gear, that is the routine Foam runs on every pickup.
Frequently Asked Questions
How often should you wash workout clothes?
Wash items that make direct skin contact after every wear: base layers, sports bras, cycling shorts, hot yoga wear, and compression socks. Outer layers that do not contact skin directly can go 2 to 3 wears. Shell jackets and technical outer layers only need washing when visibly dirty or when water repellency starts declining.
Why do workout clothes still smell after washing?
The smell is from bacteria living inside the synthetic fiber structure, not on the surface. Regular detergent cleans the surface but does not always penetrate deep enough to kill embedded bacteria. The fix is a 30-minute presoak in cold water with one cup of white vinegar before washing. The vinegar kills the bacteria without damaging synthetic fibers. Sport-specific detergents with enzyme formulas also help long-term.
Should you use fabric softener on athletic wear?
No. Fabric softener deposits a waxy, hydrophobic coating on synthetic fibers that permanently destroys moisture-wicking performance. After a few washes with softener, athletic wear stops pulling sweat away from your skin. The damage is not reversible. Use a small amount of regular detergent or a sport-specific detergent instead.
Can you put workout clothes in the dryer?
Some items can handle low heat, but many cannot. Spandex, lycra, and merino wool should never be tumble dried. Heat degrades elastic and felts wool. Polyester and nylon can tolerate low heat in a pinch, but air drying preserves the moisture-wicking finish longer. When in doubt, air dry. SLC's dry climate makes air drying fast even in winter.
Foam Laundry provides laundry pickup and delivery in Salt Lake City, Utah. Plans start at $24.99 per week with same-day turnaround and free pickup and delivery.