Bent-knee calf raises are frequently done in a seated position for comfort. Since the weight of the upper body is rested on the seat, resistance is frequently added. Using bodyweight, one leg could be draped across the other (through external rotation) to exercise unilaterally and double the weight lifted. It can also be executed by using a weight, such as a barbell, to provide resistance to the action of the calf muscles. The exercise is performed from a seated position while the weight rests on the upper leg, just above the knee. The person engaged in this exercise lifts the weight by pushing down on the balls of the feet. Due to the discomfort of higher weights on a bar, barbells used for seated calf raises are frequently padded or wrapped in a towel. There are also seated calf raise machines designed using levers that have pads built into them to protect the patella, quadriceps and tendons. -Wiki-
