"Ninety percent of an athlete's job is done on one leg, which is why instability training is so important," Rosga says. To challenge her balance and reduce injury risk, Moltzan's trainers have her do a wide range of proprioceptive moves like this single-leg squat.
How to do it: Hold a weighted ball at chest height and stand on one leg. Push your hips back and bend your standing knee to lower into a squat. Press back up, without putting your foot down. Do 10 squats on each leg.
Training tip: Moltzan is showing the most difficult option by standing on an upside-down Bosu. Start by doing this move on the floor and gradually work your way up to an unstable surface like a thick mat or core board. Once you've mastered that, you can try the Bosu.