Stand holding a barbell or EZ-bar with a palms-up (supinated) grip, your hands shoulder-width apart, the bar resting across the tops of your thighs.
Keep your chest up and head straight, with your eyes focused forward.
Pull your elbows back and forcefully contract your biceps to “drag” the bar up your torso toward your shoulders.
Complete the pull at chest/upper-abs level with a two-count squeeze of your biceps, then slowly lower the bar along the same path back to the start.
Tips
This exercise helps remove deltoid involvement so you can isolate the biceps as much as possible.
Don’t attempt to incorporate momentum from your legs or waist at the start of the movement, and resist the urge to lean backward or throw body English into your reps. If you need to, reduce the weight to perform strict reps.
While the range of motion is shorter than in a standard curl, pull the bar as high as possible to maximize the effect on the biceps.
Keep a slight bend in your knees, which takes pressure off your low back, and stagger your feet for balance.
The dragging motion should be slow and deliberate.