Exercise of the Week: Plank Position - One Foot on Exercise Ball

Difficulty: Moderate

Start: Lie on ball, face down. Walk hands out to assume plank position with lower legs (shins) or feet on ball. The closer the ball is to feet, the more difficult the exercise. Keep stomach tucked in and spine straight.

Exercise: Keeping abdominals contracted and upper body still, lift one foot/leg straight up. Hold this finish position for 10-15 seconds. Switch legs. Hold for another 10-15 seconds. Place foot back on ball and walk hands back to rest position. Repeat 2-3 times.