In general, you should wear clothes made of moisture-wicking, breathable fabrics when working out. These fabrics are lightweight to keep you cool and to keep sweat from sticking around. 100% cotton fabrics or merino wool (surprising, we know) are good options, too. Depending on the workout, women will want to wear sports bras with different levels of support. Lower-impact training like Pilates and yoga needs low support, while HIIT and cardio needs higher support. If you’re wearing loose-fitting clothes, just make sure they stay away from smaller parts of cardio machines, otherwise that can create a safety hazard.