You can sit and exercise at any time. Don't touch the ground with your toes and heels at the same time when sitting in your seat. Sometimes, just stand on tiptoe and don't lean on anything else for a while. When your toes tilt with your feet, keep your hands straight and close together as much as possible, and slowly lift them until your head repeats about 5 times. Sit up straight on the bench, and then bend down slowly until your hand touches your toe.