Begin by standing on a raised surface (such as a step or box) with the balls of your feet on the edge of the surface and your heels hanging off. Hold a barbell across your upper back and shoulders, using an overhand grip.
Keeping your core engaged and your back straight, push through the balls of your feet to raise your heels up as high as you can.
Lower your heels back down to the starting position, allowing your calves to stretch.