Wore this on a rocky six-mile trail and the stretchy fabric never once felt restrictive on the climbs. The adjustable waistband is the real winner though, I cinched it tighter for the descent and it stayed put.
The pockets on this skirt actually hold my phone and keys without sagging, which I didn't expect from something this lightweight. The adjustable waistband saved me on a hot day hike when I wanted it a bit looser.