Olalla says: land each jump on the balls of your feet instead of the entire soles. This will help distribute the weight across your knee and ankle joints.
Exercise will expire in
1Stand up straight with your feet together and arms at your sides
2Jump up, spreading your feet to shoulder-width apart while raising your arms overhead
3Quickly jump back to the starting position with feet together and arms at your sides
4Repeat as fast as you can with good form for one minute
