The lying cable curl is a good exercise for isolating the biceps. Set up for the exercise by attaching a straight bar to a low pulley cable and selecting the weight you want to use.

Sit on the floor in front of the cable machine with your feet resting against it.

Grip the bar with an underhand grip (palms facing up) at around shoulder width and lay back on the floor.Your body should be flat on the floor.

Keeping your upper arms on the floor, slowly curl the bar up as far as possible.

Squeeze the biceps, and then slowly lower the bar back to the starting position.

Repeat for desired reps.

Exercise Tips:

Keep your upper arms flat on the floor.Don't allow your elbows to come up as your curl the bar up.

Keep the rep timing slow and control the weight on the way down.