Just a word to the wise. . . When anticipating a very vigorous and concentrated workout with the allowance of time- DON'T forget to warm up your FEET! Get them WARM with a light 5 minute warm-up then STRETCH them! Concentrate on making circles with your toes- then let the stretch continue to your calves then then thighs, etc. DON'T get foot lock up or an ankle sprain!!! Before you start the intensity of your workout- whether it be by yourself, with a friend or a video- stop. check your body. Is EVERYTHING from toe to head WARM and LOOSE? If not- warm up till it is. If so- GET GOING!!! Happy MOVEMENT!