1, use the fitness ball to lie on the fitness ball, support the forearm on the ground, connect your hands and fingers, and support the ball in the center of your body.
2. Lift your legs up and make a 45-degree angle with the ground to make your body in a straight line.
3, contraction of abdominal muscles, toes outward, legs outward apart, V-shaped. The gluteal muscles contract and the heels slowly close.