Quick Answer: Seven checkable details — fiber composition percentage, fabric weight, stretch recovery, seam type, colorfastness under stretch, weave tightness, and the specific spandex percentage — reliably predict how leggings will hold up over months of washing and wear, letting you catch a poor-quality piece before you ever get it home.

Here are all seven, in the order worth checking at the store or before clicking buy online.

### 1. Fiber composition percentage

Check the label for the actual nylon-to-spandex or polyester-to-spandex ratio. A spandex percentage below roughly 10% often means less shape retention over time, while 15-20%+ generally holds its stretch and shape considerably longer through repeated washing.

### 2. Fabric weight

Heavier fabrics (checkable by feel, or listed as gsm/grams-per-square-meter when available) resist pilling and see-through far better than thin, lightweight fabrics, especially in lighter colors where thinness shows up fastest under stretch.

### 3. Stretch recovery

Stretch the fabric firmly in the store and watch how quickly it snaps back to its original shape. Slow or incomplete recovery is an early warning sign of lower-quality spandex that will loosen noticeably faster with washing.

### 4. Seam type and construction

Look for flatlock stitching (flat, interlocking seams) rather than simple overlocked seams, since flatlock seams both feel less irritating against skin and hold up better under repeated stretching at high-movement points like the crotch and knees.

### 5. Colorfastness under stretch

Stretch the fabric and check whether the color lightens or fades visibly at the stretch point. Fabric that visibly pales when stretched is more likely to show permanent stretch-marks of fading (especially at the knees and hips) after regular wear.

### 6. Weave or knit tightness

Hold the fabric up to a light source — a tightly knit fabric blocks light almost entirely, while a loosely knit one lets light through even before any wear, predicting see-through issues that will only worsen with washing and stretching over time.

### 7. The specific spandex percentage relative to the base fiber

Beyond just checking that spandex is present, a higher spandex percentage relative to nylon or polyester (closer to 20% than 8-10%) is consistently associated with better long-term shape retention across most reputable third-party fabric testing and reviews.

TL;DR:

• Fiber ratio, fabric weight, and stretch recovery predict shape retention over time
• Flatlock seams and tight weave/knit predict durability and opacity
• Colorfastness under stretch reveals future fading at high-stretch points
• Checking all seven in-store takes under a minute and avoids most quality surprises

A quick physical check catches what marketing language alone almost never reveals about how a piece will actually age.

See It in Motion

Seen here: Super High Waist Embossed Yoga Leggings with Inner Pocket — shop it on bubblelime.com