A 50-minute, high-energy cardio workout, plus a 30-minute condensed version for when you have less time to work out. Michelle Dozois instructs.

The intensity is about right for intermediate exercisers. Advanced beginners may find it a bit of a stretch, but then, a challenge is good if you want your level of fitness to progress. This routine probably works best on wood floors — you do some sliding and twists — although I had no problem doing it on a rug.

This is a very satisfying, longer cardio workout. Intense, but not impossibly so, lots of choreography, but it's not hard to learn, not too dancey (for those who dislike dancing), a few kickboxing moves without being too aggressive about it (for those like me, who hate fighting and have no desire to aim at "opponents"), a good warm up and nice cool down (although I would recommend some extra stretching at the end). Michelle Dozois is a veteran pro and she knows what goes into a quality exercise DVD — it's not just the exercise. Good, non-fancy cinematography and a well-laid out set are also crucial — all the better to show the moves clearly. Even better, Dozois uses her clients as the other exercisers. These are women who have done Dozois' Body Breakthru program and seen results. A couple of them are still en route to their ideal weight. Want inspiration? Then check out their stories on the DVD. The woman who does the modified versions of each move is especially motivating (I'd love to have her as an exercise buddy!). If you don't have 50 minutes, there's a 30-minute version that uses three of the six segments, and still gives you an excellent workout. It's worlds better than the shorter version of Dozois' Your Best Body Circuit (another in the Body Breakthru series). If you're an intermediate, I recommend this DVD wholeheartedly. If you're an advanced beginner, I recommend it even more emphatically — master it and ta da! You will be an intermediate exerciser.