The cable curl is a biceps curl with a straight bar on a low pulley: constant tension through the whole range.
1Starting positionStart2End positionFinish
Setup
Face a low pulley and take a straight bar with an underhand, shoulder-width grip. Step back half a pace so the cable runs at a slight angle. Elbows pinned to your sides, torso upright.
Execution
Stand tall, take the low-pulley handle with an underhand grip at shoulder-width, elbows at your sides — starting position.
Exhale and curl the handle up to your shoulders.
Inhale and lower it back down slowly.
Common mistakes
Elbows drift forward and up — they stay put, only your forearms move.
Rocking your back — if it won't go without a swing, the weight is too much.
Not straightening your arms at the bottom — full range grows the biceps better than half.
Curling your wrists at the top — keep the hand in line with the forearm.