Review (2/5): These are hairbands more than headbands.
Generally, silicone strips, or "bars" as the description reads, are there to keep hairbands from slipping off of hair. On sweat they're going to 1) block your pores where the sweat needs to come out, and then 2) slip around from all the sweat moisture that's accumulated underneath them. These are thin and do not absorb much beyond light perspiration. They don't wick away any substantial amount of sweat fast enough. The material is soft, stretchy, and comfortable but they don't perform the way I need them to. I'm not happy with my purchase.