If you're just getting into running, biking, or other kinds of cardio exercise, it's important to make sure you're working hard without overdoing it. Keeping a close eye on your heart rate can help you stay in the sweet spot, which, for an average 20-year-old, is between 100-170 beats per minute, according to the American Heart Association.
Plenty of fitness trackers can help you keep tabs on your heart rate while you're working out. But if you're looking for an alternative option, Under Armour and JBL may have the answer: The Under Armour Sport Wireless Heart Rate, a pair of Bluetooth earbuds that double as a heart rate monitor. Whereas most fitness trackers and smartwatches detect your heart rate via your wrist, the Sport Wireless earbuds do so with a sensor tucked into one of the buds themselves.
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During a recent morning workout, it took me a little fiddling to get the Sport Wireless to find my heartbeat — it turns out I incorrectly attached one of the three included eartips, leaving the sensor blocked. But once I realized my mistake, the Sport Wireless earbuds gave me roughly the same reading as my Apple Watch and my gym's stationary bike. (The eartips do have left/right markings, but they're hidden away inside where they're hard to spot.) A nifty touch sensor on the right earbud lets you get an audible readout of your current beats-per-minute with a quick tap. And Under Armour's UA Record companion app can help track your progress over time.
You probably won't care much about audio fidelity while you're pounding the pavement, but the Sport Wireless happily doesn't skimp on sound. Once you decide which of the three included eartips fits best for you, they're plenty comfortable, too. (That was a nice surprise; I usually hate workout earbuds.) And I got battery life around the advertised five hours, plenty for pretty much any gym session or jog.
The Sport Wireless won't replace your everyday headphones. There's not enough battery life for that, the buds are a little too bulky to look good with street clothes, and the heart rate's glowing green sensor can make you look like Locutus of Borg if you're not careful to place the buds in your ear just so. But if you're looking for a pair of workout headphones that can help track your runs without a dedicated fitness monitor, these can do the job nicely.