I am looking for padded bicycle shorts. When trying on candidates, all of the "leg grippers", as described in this answer, feel uncomfortably tight around my thighs, which are on the meaty side. They feel as if they might start to cut off some circulation to my lower leg. Is this common in new pairs of shorts? Do the leg grippers stretch out, or will they retain this uncomfortable tightness?
The short answer is "sometimes". There are a few different styles of leg grippers. Some are more likely to stretch than others.
My favorite kind have a slightly different material than the rest of the short, similar "strechiness" but only slightly tacky on the inside. These, I've found do stretch out over time but in similar fashion to the rest of the short's material.
There is another type that tends to stretch out which is, more or less, a cinched, folder over piece of the same material found in the rest of the short. As mentioned, they do tend to stretch out and don't often stay in place as well as the tacky kinds.
There are also grippers that have little silicone "dots" to help hold in place. I usually find that they're less binding but they can be put on any material so the stretch durability is hard to nail down