Instructions:

1. Sit on a preacher bench with your chest against the pad and your arms extended over the edge, holding a barbell with an underhand grip.
2. Keeping your upper arms stationary, exhale and curl the weights while contracting your biceps.
3. Continue to raise the bar until your biceps are fully contracted and the bar is at shoulder level.
4. Hold the contracted position for a brief pause as you squeeze your biceps.
5. Inhale and slowly begin to lower the barbell back to the starting position.
6. Repeat for the desired number of repetitions.