HOW: Begin this exercise with a heavy barbell on the squat rack, one that you will not be able to move. Get set up with the bar resting on your shoulders. Stand on one leg and push up into a heel raise pushing against the immovable weight. Push for the prescribed amount of time before returning to the starting position.
FEEL: You should feel your calf muscles working as you push up into a heel raise.
COMPENSATION: Be sure that the object you are pushing up into is immovable as you want this exercise to serve as an isometric meaning that your body is not working through a given range of motion.