The problem with the waist, sit-ups, or leg ending, is to lie flat on the bed, put your hands flat, lift your legs up 45 degrees together, keep them for two minutes, take a break, do them for two minutes, and so on.

For thighs, put your hands on your head, keep your heels together, and so do your toes. Keep your upper body upright. When squatting, pay attention to your knees together. Do it in groups of 20, and do it in groups of 4 every day to ensure that it is effective for two weeks.

That's what I did when I was a soldier