Sueb, you made me go look at my Athleta sweatshirts (more than one in a light color). Two were mostly cotton, plus polyester and spandex. The other (blue) was a similar fabric to yours and it’s fine, thankfully.

I’m wondering if it’s something to do with your washing machine? I have to use a cleaner in mine more frequently than I’d like to admit, plus wipe out the grungy stuff. Mine is 7 years old (LG top loader) and it still needs hands-on care just like a front loader although not as much. I use a liquid detergent.

I would think it was my washer too, except that this only happened with these two items, and not in the same wash, either. We do have a front loader which has its own issues, but in terms of affecting fabrics I haven’t noticed anything.

And I just put away yet another load of laundry and it included the matching sweatpants to the above-mentioned Athleta shirt. Guess what, same marks are on them too. So weird.

I used to have that issue from time to time on my old front loader. Although it was more random, not specific items. You could try putting some dawn DW liquid liquid t on those spots, rub it in really well . You don't have to wash them right away unless you happen to be doing a load. See if that might get the spots out.

Sounds like have you ever used fabric softener? Those manmade fabrics hate fabric softener and it can make weird marks. I second Dawn.

Definitely try Dawn. It takes out lots of "spots"!

I would call customer service at both of those places and see what they say.

Another vote for Dawn.

I've never used fabric softener and still had them. My old front loader was a Bosch and now I have an LG and haven't had the issue. I use powdered detergent.

Same issue with this fabric on an Athleta sweatshirt- I used every spot remover I could think of even Dawn dish soap... still there. Very annoying since I only wore it once! I asked in the store what they might recommend and they said the company knows about this fabric and really doesn't know what can work. So I'm stuck with a pricey top that has a dark stain in the front - my new housework garb.🤨 So buyer beware- avoid the Seasoft fabric items from Athleta, or similar other athleisure stores!

I haven't had this issue, but it reminds me of certain cotton batting that may have bits of seeds and cause stains after washing -- not good if using while or light backgrounds. The cellulose used to make the Modal is from beech trees -- so similar but different plant material. I did a search (this conversation appeared in the results -- haha) and found that you can get dark stains from reactions with some fabric softeners or hard water. I found another hit where someone said water stained their fabric (reminds me of silk and water rings if you spot clean - use distilled water?), but I saw one site that says even those sometimes don't come out.

I apologize for the length of this AI summary, but it it is more comprehensive and seems to address the question here than individual sites' laundry suggestions. The last line seems to address your issue, but I'm not sure if you can reverse the spots. Hope it helps. I do trust Dawn and OxiClean (hydrogen peroxide) on most fabrics.

Dark spots on Modal and TENCEL™ fabrics can occur from a variety of sources, including typical stains (oil, wine, blood) and, in some cases, a reaction to fabric softeners or hard water. These fabrics are delicate, so specific care is needed to remove the spots without damage. Causes of Dark Spots

• General Stains: As moisture-wicking fibers, TENCEL™ Modal can absorb liquids quickly, causing stains to set in if not addressed immediately.
• Oils and Grease: Body oils, lotions, or cooking grease are common culprits that show up as dark spots.
• Fabric Softener: Man-made fabrics can react poorly to fabric softeners, which can leave oily-looking, random marks.
• Water Marks: Some users report that even plain water can leave temporary dark marks that look like stains until they dry completely.
• Washing Issues: Using too much detergent or having hard water may also contribute to spot formation.

Stain Removal MethodsAvoid harsh chemicals like bleach, which can damage the delicate fibers. Instead, try the following methods: Stain Type Recommended Treatment

General Stains Rinse immediately with cold or lukewarm water. Spot treat with a gentle, chlorine-free stain remover or a mild wool laundry detergent.

Oil/Grease Stains Apply a small amount of liquid dish soap (like Dawn) directly to the wet stain, gently rub in, and then launder as usual. The dish soap acts as a degreaser.

Dark Stains (wine, blood) Soak the stain in cold water immediately to prevent it from setting. Then, soak in a chlorine-free enzyme cleaner and cold water for at least 15 minutes, or longer for older stains.

Stubborn or Unknown Stains A mixture of 1 tablespoon of vinegar and 4 tablespoons of water applied to the spot, left to sit, and then washed can be effective.

Washing and Care Tips

• Avoid Fabric Softener: Do not use fabric softeners on TENCEL™ or Modal fabrics.
• Gentle Cycle: Turn the garment inside out and use a gentle cycle with cold water.
• Gentle Detergent: Use a mild detergent that is effective in cold temperatures.
• Do Not Wring or Scrub: Gently dab stains and press water out; never wring the fabric, as this can damage the fibers.
• Hang Dry: Air drying is best. Avoid tumble dryers, which can damage the fabric and cause premature fading.
• Pre-Wet Before Washing: If you notice a pattern of white or dark marks after washing, try pre-wetting the entire garment before putting it in the washing machine to ensure uniform saturation.

Going a different route -- could you add embroidery, sashiko or other decorative stitchingor applique to cover or screen the spots? Or dye the garment darker (might still be spotted though). You might have a moving target with more spots, but its a thought - especially if cleaning methods might avoid future spots. The fact that a particular brand is having so many problems makes me think their fabric supply may be the problem.

Sue B this post just bolsters all my misgivings about athleisure! 😬

This post is from almost a year ago, fyi.

The garments are long gone.

What have you replaced them with? Is there any equivalent fabric that doesn’t stain?