Group lesson During this open hour the emphasis is not on your fitness, but more on the stamina of particular muscle groups (especially your abs, legs and bottom). If you’re not that keen on jumping up and down but you wish to strengthen your muscles, then you’re definitely in the right place during this open hour. Because of the different weights everyone can work on the enlargement of their muscles at their own level. This year body fit will take place several days of the week at noon: perfect for an active lunch break! Remember to always bring a towel for floor exercises.