Oblique crunches

Instructions

Lie on the floor, with the bottom of your back glued to the floor, hands against your temples. Raise your legs and form a 90-degree angle with your knees.
Slightly lift the upper back off the floor and touch your right knee with your left elbow, without moving your knees et without pulling your head with your arms.
Hold this position for one second and go down without completely touching the ground with your back (so the muscles stay contracted).

Muscles