Its the roughest lower body exercise ever invented, you get a deck of cards and lay them on the ground in a row about 1 step apart from each other, you go to the first card, do a squat and pick it up, then take a step to the next card, do another squat and set the first card on top of it, stand back up, do another squat and pick both cards up, stand up and go to the next card, squat down and set 1 of the 2 cards you have on it and stand up, then squat down and put the other, then squat down and pick up both, continue like that until you can't go any more. it's killer, works your calves, thighs, lower back, glute's, your entire lower body.