When you're working out with dumbbells, stopping to add or remove weights can disrupt the whole flow of things. In order to keep those stops as short as possible, NordicTrack has introduced its voice-controlled iSelect Adjustable Dumbbells.

The iSelect system includes two dumbbells, along with a series of 5-lb (2.3-kg) square weights which are incrementally added onto them. Each dumbbell can hold a total of 50 lb (22.7 kg).

Whenever users wish to adjust the weight load, they start by placing the dumbbells in a system-specific tray that is paired to a third-party Amazon-Alexa-enabled smart speaker or other device. They then speak a command such as "Alexa, set weights to 35 pounds." A motorized system in the tray responds by adding or removing weights accordingly, within a matter of seconds.

Along with requesting specific total weight loads, users can also ask to have the load increased or decreased by a certain amount, or they can ask for a user-specific weight load that has been preset for a given dumbbell exercise (i.e: "Alexa, set weight for bicep curls"). The system allows such presets to be programmed in for 15 different exercises.

All of that being said, users can also physically control the motorized weight-swapping mechanism via a weight-adjustment dial on the tray. A digital readout above that dial shows how much weight is being selected.

The NordicTrack iSelect Adjustable Dumbbells system is available now via Amazon, priced at US$429. That price includes a 30-day family membership in parent company iFit's online training session platform, which is not required in order to use the dumbbells – also, prospective buyers should be aware that the membership will proceed to auto-renew at $39 per month unless stopped.