Band Skull Crusher

The lying triceps extension against a band anchored low behind the bench; the band keeps pulling at the top, where dumbbells go slack.

How to do it

Setup

Lying on a bench, head toward the band's anchor, the band held overhead, upper arms angled back toward the head.

Steps

Bend only the elbows, lowering the hands behind the head.
Keep the upper arms still.
Extend the elbows until the arms are straight over the face.

Common mistakes

Upper arms swinging toward the hips: the elbows stay pointed back. Letting the band snap the hands back: control the bend. Band anchored too high: tie it low behind the bench so it pulls along the forearms.

Breathing

Exhale on the extension, inhale on the stretch.