No pulling. Some folks like to lock their fingers behind their head while doing sit-ups. That's fine, but be sure not to pull yourself up or to jerk your head toward your chest. Your arms should be relaxed during this exercise.

Don't brace your feet under anything. If you do, you're more likely to use your hip flexors to lift your body up, and your abdominals will be spared. That's not the point of the exercise. Keep your feet free and let your spine curl as you come up. Don't bend from the hip.

2torial #0409: Learn2 Perform Basic Calisthenics Do some sit-ups Lie on your back with your knees bent and your heels shoulder-width apart, 10 to 12 inches from your bottom. Pull your chin in and cross your arms over your chest in an "X" position. Keeping your feet flat on the ground, curl yourself up about halfway toward a sitting position. Use only your abdominal muscles (not your back muscles). If you feel your tailbone touch the ground, you've gone too far. Lower yourself back to a lying position slowly. Remember that your muscles are exerted both going up and coming down. Take advantage of that. If you haul yourself up into a sit-up only to let your body flop back down, you've missed half the exercise. Lower yourself back down slowly, feeling the tension. Try to let each vertebra fall one by one. Repeat 10 times. If you can easily do 10, aim for 20. Step 3