Straight-arm pulldown:
Stand at an adjustable cable machine and grab the lat pulldown bar with an overhand grip that's about shoulder-width apart. Keep your knees slightly bent and feet shoulder-width apart. Exhale and pull the bar down to your thighs. Your arms should remain straight, elbows locked. Pause, then return to the starting position.
Do not bend your arms. Make 1-2 sec pause at the top position of the movement. Do not raise the handle too high. Keep the right breathing pattern – exhale when you pull the cable down and inhale when you raise it.

Straight-arm pulldown.