Squat-Proof Coverage Solutions for Running Shorts: Common Failure Causes and Fixes
Below are the failure patterns most often seen when squat-proof coverage affects running shorts, with the correction for each.
Failure: hidden until worn
knitted fabric loses opacity when it stretches over the body usually appears after several sessions. Because it develops slowly, it reaches the customer instead of the inspection table. Because high cadence movement plus perspiration at the waistband, target checks are made on a worn sample rather than flat fabric alone.
Cause one
low course density so the interstices open under tension. Keep AATCC 183 transmission with photography under 60% extension named in the tech pack so every lot is measured the same way.
Cause two
fine filament yarn with poor covering power. Where running shorts is worn for road, trail and track training, set tolerances around that range of movement.
Cause three
light shades that transmit light more than dark ones. Any change to lightweight woven or knit body with a knit liner requires re-testing against opacity above 96% at 30% extension before bulk is released.
Correction and prevention
Apply raise course density to 34-40 courses/cm first, then verify against opacity above 96% at 30% extension using AATCC 183 transmission with photography under 60% extension. Lock the corrected settings into the bulk recipe so repeat orders behave identically. Past reports from AATCC 183 transmission with photography under 60% extension help the mill reproduce the same recipe on the next order.
