An alternating crunch that brings one elbow toward the opposite knee while the other leg extends. It trains the rectus abdominis and obliques through flexion with rotation.
Primary muscles
Secondary muscles
This information is general fitness guidance, not medical advice. Stop if you feel pain and consult a qualified professional.
Main muscles working (thicker lines)
Lie on your back with fingertips lightly behind your ears, shoulders curled slightly off the floor and knees lifted to tabletop.
Brace your abs and keep your lower back pressed toward the floor.
Rotate your torso to bring your right shoulder toward your left knee while extending your right leg.
Switch sides, bringing your left shoulder toward your right knee as the left leg extends.
Continue alternating at a controlled pace.
Breathing: Exhale as you rotate to each side, inhale as you pass through the middle.
Rotate from the ribs, not the elbows
Extend the leg fully
Slow and deliberate
Pulling the head forward with the hands
Flapping the elbows instead of rotating the torso
Rushing through reps
Raise the extended leg higher if your lower back starts to arch.