Hanging leg raises:
Stand in the frame with your arms resting on the arms of the chair. Grab on to the handles of the chair, if it has them. Check that your arm position is firm (you need to be able to lift your bodyweight from the floor). Inhale as you engage your abdominal muscles to prepare for the leg lift. Bend your knees and raise them upward until your quads are parallel to the ground. With an engaged core, exhale as you lower your legs in a controlled movement until you're back in the starting position.
Mistakes and Recommendations:
You can swing your legs back a little before you start lifting. This will make the exercise easier. Do not rely on Momentum too much – keep your movements controlled.
Hanging leg raises are perfectly suitable for both men and women. Combine it with crunches and other exercises to train your abs.

Hanging leg raises.