Modified Side Jackknives (abs)

Modified Side Jackknives isolate the oblique abs for the kind of side cut that turns heads at the beach, with an easier setup than a full jackknife.

Lie on your side with legs stacked and slightly bent, one hand supporting your head. Simultaneously lift your top knee and curl your upper body toward it, bringing your elbow and knee together, then lower back down with control before repeating on the other side.