Jand Raise

Lie on the floor, knees bent at 90 degrees, feet flat on the floor, arms crossed over chest. This will be your starting position. Squeeze your buttocks and tighten the back of your thighs. Inhale deeply, filling your lungs with air. Exhaling slowly, lift the torso. Tip: It's important to tighten your glutes and hamstrings, as this isolates your hip flexors, allowing you to get the most out of your ab muscles. On an inhale, slowly return to the starting position. Complete the required number of repetitions. This exercise was developed by a Czech physiologist, Dr. Vladimir Janda. This is one of the most difficult variations of the regular sit-up, as the load is only on the rectus abdominis, and the work of the hip flexors is completely isolated.