Spending time with a personal trainer can be a prudent investment in your workout regimen, especially if you're trying to break through a plateau or learn a new skill. It is, however, expensive as hell, and the benefits that flow from one-on-one instruction are a little more difficult to realize when your activity of choice is running. Sure, you could run on a treadmill while the trainer supervises, but every time I've seen this setup, everyone involved looks uncomfortable. The trainer occasionally offers direction or encouragement, but otherwise, you’re paying them to just... stand there. Watching a session evaporate while your alleged coach stares off into the distance and fights the temptation to scroll through Twitter is probably not the best use of your fitness budget.

In a valiant effort to address this conundrum, LifeBeam Labs has cooked up an artificial intelligence running coach called Vi, which is basically a geotracker and fitness watch stuffed into a pair of Harman Kardon bluetooth earbuds, and brought to life by a disembodied female voice. (LifeBeam provided us with a model to try for this review.) Using biosensors, tracking devices, and a smartphone app, it logs things like speed, distance, heart rate, and step rate for each of your runs. What the Vi headphones provide that those other gadgets don't is real-time, personalized coaching that occasionally pipes up (think: Cortana to Master Chief) to call out instructions, note your progress, and/or just tell you to stop loafing.

This "training" is more than just, like, Siri yelling at you to go faster. For example, Vi is knowledgable about the health benefits associated with decreasing one's step rate. If she senses that yours is too low, she'll offer to play a beat—it sounds like the instrumental to an Awolnation deep cut, and honestly, it kind of bangs—and tell you to match your steps to it. Eventually, she gets you get back to your music (or your podcast), but will issue friendly reminders if you carelessly lapse into long-striding habits of old.

The people who made this thing tried really hard to make the AI a little less A, with mixed results that occasionally stray into uncanny valley territory. She knows stuff like your location, and the weather, and the time of day, so if you're a morning runner, you’re pretty much guaranteed to hear some overexcited quip about how much she loves attacking the pavement early. (This is, perhaps, her most accurate parallel to a real personal trainer.) However, the headlines-based information that she occasionally downloads from The Cloud and spits back in the form of friendly banter can be a little much. Having Vi, a robot who lives in my ears, greet me one morning by seriously discussing the merits of seeing It in theaters was... a little unsettling.

At $250, Vi isn’t cheap, and whether it’s worth the investment depends heavily—like most fitness gadget purchases—on your goals. The people who will get the most out of Vi are probably those who are just starting to run regularly. Getting into running in the way that, like, runners are into it is intimidating! (Do you just... go? Where? For how long? How far? How fast? And so on and so forth.) Vi kind of pulls back the curtain by providing concrete, personalized, metrics-based feedback and meticulously logging your progress.

The cost is a little tougher to justify for more experienced runners. Step rate coaching is useful, but you probably don't need expensive headphones to teach it to you once you're familiar with the concept. You might also find some of her interjections (“You’re cruising! Great going, Jay!”) unnecessary and tiresome. That said, if you’re already in the market for a high-end pair of running earbuds, Vi’s extra features might be worth paying a marginally higher price. Besides, the frequency with which she interrupts your mid-run reverie can be adjusted within the app. Good luck finding a personal trainer with that feature.

Lifebeam Vi A.I. Fitness Tracker

$250, buy now at Amazon

Watch Now:James Marshall Tackles a 140 Mile Race Through the Sahara DesertJay Willis is a staff writer at GQ covering news, law, and politics. Previously, he was an associate at law firms in Washington, D.C. and Seattle, where his practice focused on consumer financial services and environmental cleanup litigation. He studied social welfare at Berkeley and graduated from Harvard Law School... Read moreRelated Stories for GQHeadphonesRunningRunning