The Bosu ball is a balance training tool sometimes combined with Pilates exercises to challenge your core muscles. The Bosu resembles a stability ball cut in half and placed on a round plastic platform. The Bosu's name means "both sides up" or "both sides utilized," which alludes to the option of placing the Bosu with either side facing up. Being able to position the Bosu on either the flat or rounded side offers offers more variety for doing Pilates exercises.
Plank with Twist on the Bosu
The plank with twist on the Bosu is a challenging core exercise. The Bosu ball is placed with the round side on the floor. Place your hands in the center of the platform with the arms straight and then step your feet back to get into plank position. Your body is in a diagonal line from your heels to the top of your head when in plank. Squeeze your thighs together and also tighten your glutes and abs. Next, raise your left leg straight toward the ceiling, then bend the leg into your stomach and rotate it under your toward your right hip. Reverse the full movement and put your left foot back to the floor. Repeat with your right leg.
Side Bends on the Bosu
The side bends is another exercise for your core, particularly the muscles on the sides of your body such as the obliques. This Bosu exercise uses the round side up. To perform this exercise, sit on the floor next to the Bosu and then lie the right side of your body onto the ball. Lie your right arm on the floor above your head with the palm up and relax your left arm on your side. Bend your right knee but extend your left leg straight in line with your torso. Then, slide your left foot toward your foot and raise your torso into the air, bringing your right arm up with you. Curve your arm and torso into a crescent moon shape as you bend to the left. Lie back down to complete a side bend on your right side. Roll over to work to repeat the exercise on the other side.
The Saw on a Bosu
The saw is a classic, beginners Pilates exercise that is modified to be more challenging by sitting on a Bosu ball. You can even hold a body bar or barbell across your shoulders as you do the saw for even more challenge to your core. To perform the saw on a Bosu, sit on the platform with the rounded side on the floor. Extend your legs straight in front of you and open them to 45-degree angles from your upper body. Lift your arms to your sides at shoulder level with the palms facing down. Then, twist your upper body to the right and look over your right shoulder. Twist back to center and then rotate to the left. You may keep your spine straight or incline your torso forward slightly as you rotate as if reaching for your opposite foot.

