Crunches: elbow to the opposite side with hands behind the head

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 and obliques; match resistance and range to a beginner level and never force a painful repetition.