Hanging Leg Raise
Hang from the horizontal bar with a wide overhand grip, with your toes pointing toward the ground. Keeping your legs straight or bent, contract your abdominal muscles and lift your legs up until your thighs are parallel to the floor, or continue to lift your legs until your toes point toward the bar. Hold for a few seconds and then return to the starting position, avoiding shaking.
Dang external oblique muscles to tighten the abdomen
Use an overhand and wide grip to hang from the horizontal bar with your legs hanging down Hanging under your hips, knees together, toes pointed toward the floor and slightly turned to one side. Start the movement from your hips, slowly draw in your abdomen and lift your knees to the side of your body. Squeeze your abdominal muscles until your thighs are parallel to the floor. Hold for a few seconds and then return to the starting position, avoiding shaking.
Windshield wiper
Hang from the horizontal bar with an overhand, wide grip, with your toes pointing toward the ground. Take a deep breath, contract your abdominal muscles and lift your feet, with your ankles pointing towards your forehead. From this position, carefully and slowly turn your legs 90 degrees to the right, then to the left. Keep your hips bent throughout the movement and lift your legs as high as possible.