She does multiple reps of leg lifts on each leg on an unbalanced BOSU ball to challenge the core.
If you don't have a BOSU ball, here's how to do double leg lifts:
- Lay flat on the ground with your legs extended straight up toward the ceiling. Place your hands underneath the back of your head. For added stability, Austin recommends laying your arms out to your side, allowing the palms to grip the floor much like you would in a push-up position.
- Pressing your lower back into the ground, slowly lower both legs down toward the floor, then slowly raise them back up. If this is too difficult, lower them as much as you can, or lower one leg at a time.
- Complete 10 to 15 reps.
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