Your strength training routine is about to get a lot smarter. NordicTrack on Tuesday launched the first voice-controlled adjustable dumbbells that work with Amazon Alexa. 

The NordicTrack iSelect Adjustable Dumbbells, available now on Amazon.com for $429, can be adjusted from 5 to 50 pounds, in 5-pound increments, with just the sound of your voice via an Alexa-enabled smart speaker (sold separately). 

Just say "Alexa, set weight for deadlift," and the motorized weight selector will respond within seconds, adjusting the iSelect dumbbells to your pre-set deadlift weight. 

They support pre-set weights for 15 classic dumbbell exercises, including biceps curl, overhead shoulder press, lateral shoulder raise, front shoulder raise, triceps extension, bent over row, chest press, squat, deadlift, lunge, lateral lunge, wood chop, chest fly, reverse fly and renegade row. As your strength increases, you can adjust the pre-set weights as necessary. 

You can also use voice commands to set weight to a specific amount. Just say "Alexa, set weights to 35 pounds," for instance. Or, you can use your voice to increase or decrease the weight with commands like "Alexa, increase weight by 10 pounds."

If your Wi-Fi isn't working or Alexa goes down for some other reason, you can manually adjust the weight with a knob. 

The iSelect dumbbells and all the weight plates are stored in a tray measuring just 21 by 19 by 16 inches (LWH). With the ability to replace the equivalent of 20 dumbbells, they're especially appealing if you're short on space. 

The iSelect dumbbells do not require an iFit subscription, but come with a one-month membership, offering access to a library of thousands of workouts. The Select dumbbell tray features an integrated tablet holder so you can easily follow along with iFit workouts. You can also stream iFit workouts on your phone or TV. 

After the 30-day trial, the iFit membership will auto-renew at $39 per month plus tax, unless you cancel. The iFit team tells PCMag they are busy filming classes for iSelect dumbbell users. 

Stay tuned for PCMag's full review of the NordicTrack iSelect dumbbells. In the meantime, check out our review of the NordicTrack Vault, the company's other space-saving smart strength training product. 

The NordicTrack iSelect dumbbells join a growing list of sub-$500 smart strength training devices, including the $495 Tempo Move, which we are currently testing for an upcoming review, and the $495 Peloton Guide.