>These are a great for improving lower body strength and all you need is a stair or stable step stool. Facing the stairs place one foot on bottom step. Slowly lift yourself up and lower yourself down. Try not to push-off with the bottom foot. Perform 10 in a row and work up to 15. Take a break and repeat with other foot up on step.

Similar to the squat, you can do Speed Step-ups: Do as many as you can in 30 seconds; rest 30 seconds and do it again. Work up to 3 sets per leg.