Band Jackknife Sit-Up

A jackknife sit-up against a band strapped to the ankles from an anchor behind the feet: the knees tuck in as the chest comes up to meet them.

How to do it

Setup

On the floor with the legs long, ankle straps on a band anchored low behind the feet, arms along the sides.

Steps

Draw the knees in against the band as the chest curls up.
Sit up tall with the arms reaching past the knees.
Extend the legs and roll back down under control.

Common mistakes

Letting the band snap the legs out: extend them slowly. Feet slamming the floor between reps: they hover. Rocking back to launch the next rep: stop still at the bottom.

Breathing

Exhale on the tuck, inhale extending.