'If you're doing any high-impact activities, where you might sweat, or even in hot weather, wearing Crocs, with or without socks, may not be the best option.' Even the way you walk can be affected by wearing Crocs for too long, research shows. 'Mechanically, wearing Crocs for an extended period – particularly without using the backstrap – can cause you to walk differently,' says Dr Thomas. 'Crocs have no heel counter or support, so the shoe doesn't hold your foot – your foot holds the shoe,' she explained. 'Wearing Crocs occasionally to the pool or for short trips is fine.