Set 1: Lunges with jump-changing legs
Lunge forward with your left leg, holding your back straight and keeping your right knee lower than the left one.
Jump up as high as you can, helping yourself with your arms.
Change your legs in the air, landing in a lunge position with your right leg.
Begin with 10-12 reps, changing your leg each time before landing. Gradually increase the number of reps to 30.