The Best Wearable Tech of 2021
Devices for passing the toughest training milestones
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Garmin Descent Mk2 Smart Dive Watch ($1,300)
Like its predecessor, the new Descent Mk2 has a digital compass, GPS, five dive modes, and a host of fitness functions like heart-rate monitoring and sleep tracking. Now it offers pulse oximetry, and its screen is roughly 15 percent larger, while only increasing the body by one millimeter. The pricier Mk2i ($1,500) pairs with Garmin’s new T1 transmitter, which uses sonar to monitor five different tanks up to 30 feet away.
Core Body Temperature Sensor ($285)
Until now, determining your internal temperature in real time required complex measures like swallowing an electronic pill. Core Body Temperature’s new sensor tracks thermal energy transfer for incredibly accurate readings. Wear it under an included waterproof sticker or via a chest strap (BYO). It pairs with Garmin and Wahoo devices to give up-to-the-minute info, so you know when to ease back or push harder.
Apple Watch Series 6 Smartwatch ($399)
Apple’s Series 5 was already the best smartwatch money could buy. This year’s update adds blood-oxygen monitoring and sleep tracking. It also integrates with the new Apple Fit subscription workout platform. It still doesn’t work with Android, but if you have an iPhone, it remains the everyday wearable to beat.
Airofit Pro Breathing Trainer ($299)
The Airofit Pro looks like a high-tech mouth guard, but it’s actually a tool for strengthening your lungs. It pairs with a phone app that runs exercises designed to build respiratory strength, vital lung capacity, and anaerobic threshold. It’s perfect for helping freedivers and surfers hold their breath longer, or giving endurance athletes a boost.
Polar Vantage V2 Smartwatch ($500)
The Vantage V2 provides more granular data than any other watch we’ve tested. In addition to typical metrics like GPS, optical heart rate, and sleep tracking, it offers tests for leg recovery and VO2 max (both running-and cycling-specific versions of the latter), and a function that alerts you when it’s time for more calories. Another feature breaks down all your data for ascents and descents in running or biking mode, including pace, distance, and vert. Still, the watch weighs just 52 grams.
Bose Sleepbuds II Earphones ($250)
Forget streaming music; these earphones are strictly for sleep. They’re small enough to fit deep in your ear (you can even wear them side sleeping), with rubber tips that block noise. Use the Bose app to download a soothing soundscape, like waterfall or ocean, straight to the buds. Then disconnect from Bluetooth and listen for up to ten hours. They’re pricey, but a good night’s rest is worth it.