For those of you looking to add an edge to your running and increase lower body tendon strength and explosiveness the Speedster workout is just what you need. A difficulty Level IV workout this is hard from set one and it simply gets no easier. But the results will astound you, plus feeling the burn is just how you know you've worked hard. Make sure your knees come to waist height during March Steps and High Knees. Land on the ball of the foot each time to offset the impact and work the calves. Be kind to yourself by not taking it easy and add EC for that super-tough effect.