Cable close grip curl

Attach a straight bar to a low pulley cable machine. Stand facing the machine with your feet shoulder-width apart and your knees slightly bent. Grasp the bar with an underhand grip, hands shoulder-width apart. Keep your elbows close to your sides and your upper arms stationary throughout the exercise. Exhale and curl the bar up towards your shoulders, contracting your biceps. Pause for a moment at the top of the movement, squeezing your biceps. Inhale and slowly lower the bar back to the starting position, fully extending your arms. Repeat for the desired number of repetitions.