LAS VEGAS—Anyone who's lifted weights knows the temptation to try and cheat on the last set, and not bring the weights up as far as your should. Using motion sensors, and connected to a smartphone app, Bowflex's smart dumbbells help keep you honest by tracking how the weights move, and only giving you credit when you've done a real rep.
Available for pre-order and shipping in February, the ST560 dumbbells cost $499. Like its SelectTech weights, each dumbbell's handle can be twisted to select any amount of weight from 5 pounds up to 60 pounds. (A $249 add-on increases the weight to 100 pounds). A small indicator on each handle shows you at a glance how much weight you've chosen.
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When you're ready to start pumping iron, the app, available for Android and iOS, will record the movement of your first rep, whatever that may be. From then on, you have to replicate that same movement for it to be counted. Within the app, which is free, there are a number of different training programs, including P90X, along with videos showing the proper form for various exercises. However, users can also create their own regimen based on their needs.
Data from your workouts can then be imported into several other fitness apps, including Apple HealthKit and MapMyFitness.
In addition to the weights, Bowflex will also sell a rack that holds the dumbbells and an iPad for $149.
Bowflex's ST560 dumbbells represents yet another interesting application of motion sensors in the world of fitness. By making sure that you lift weights properly, they could not only get you beefed up, but help prevent injury from improper movements.