Crunches on a machine abs seated

Bring the ribs and pelvis closer with a short, controlled trunk flexion. Avoid pulling on the head or using momentum to finish the repetition. Use a steady tempo: control the return phase in particular and avoid relying on momentum. Exhale through the hardest part and inhale as you recover the starting position.

Check that the movement stays stable in both directions and that the torso is not compensating. The goal is controlled loading of abdominals; match resistance and range to a intermediate level and never force a painful repetition. Set the seat, backrest and machine axis before loading it; poor setup changes the path and often creates compensations.