If you’re like me, you have a couple of standard strength workouts that you go back to time and again. Well, it’s time to mix things up, and I have just the device for you: the Valslide.

Developed by trainer-to-the-stars Valerie Waters (clients include Jennifer Garner, who reportedly used it to slide back into shape post-baby), the Valslide consists of a pair of foam-topped plastic disks; you put your feet or hands on them, then slide back and forth while doing moves like lunges and push-ups.

The accompanying DVD offers two workouts: a 20-minute routine that focuses on the Amazing Seven basic moves, and a 40-minute one that adds some slide-free dumbbell exercises to the mix. Both routines hit muscles all over your body, with emphasis on the core and lower body.

Here’s the cool thing: They’re really fun to use—so much so that I found myself pausing the DVD between exercises and making up crazy twisty dance steps. Hello, cardio! But don’t think the disks make the workout easy—just the opposite. They’re so slippery that I had to keep my core constantly engaged to stop it from collapsing unceremoniously on the floor. (And yep, I was plenty sore the next day.)

It’s worth noting that the disks work best on a carpet. You can use them on hard flooring, too, but you’ll need the special booties that come with the DVD package (or you can buy them separately).

About the DVD: The production values are pretty basic—just a simple room with Waters talking while another woman does the workout. Nothing wrong with that, but the chatter is heavy on encouragement and surprisingly light on form tips. That seemed odd, as you’d think that with your limbs sliding all over the place (and potentially putting knees, etc., at risk), proper form would be key to using the disks safely.

The upshot? These are best for experienced exercisers—and if you’re one, the Valslide may be the right motivational, er, twist you’ve been looking for.

Product: Valslide

Category: Gear

Pros: It offers a fun, challenging way to build strength.

Cons: Form tips are few and far between.

Cost: $29.99 for 2 slides and instruction booklet, or $42.47 for 2 slides, booklet, DVD, and booties at Valslide.com

Extra tip: Don’t want to spring for the DVD? Before doing the booklet workouts, watch the how-to videos on the website to see the moves in action.