The Smith machine drag curl focuses on isolating the biceps while minimizing shoulder involvement. This exercise is performed using the Smith machine, providing stability and a fixed range of motion, which helps in maintaining strict form and maximizing bicep engagement.

1. Stand in the Smith machine, holding the bar with an underhand grip.
2. Keep the bar close to your body and drag it up towards your shoulders.
3. Squeeze your biceps at the top of the movement.
4. Slowly lower the bar back to the starting position.