GearTools & Tech
2021 Winter Buyer’s Guide

The Best Fitness Trackers of 2021

Keeping tabs on training and health has never been this seamless

(Photo: Courtesy the Companies)
winter buyer’s guide

Polar Grit X ($429)

fitness tracker
(Photo: Courtesy Polar)

Military-spec construction (it’s passed MIL-STD-810G tests) and high-tech software come together in this training-oriented watch. It works with Polar’s Flow app, which allows you to map out your own plan and then suggests adjustments as you go, depending on metrics like speed and effort. It also uses heart-rate data to keep you in the proper effort zone, and will even tell you how much fuel you’ll need based on your session time and intensity, the portion size of your preferred sports fuel, and your stored vitals—and reminds you to keep refueling as you go, to prevent bonking. Another feature gives you separate metrics for uphill and downhill splits.

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Garmin Fenix 6 Pro Solar Edition ($850)

fitness tracker
(Photo: Courtesy Garmin)

Garmin’s do-it-all flagship multisport wearable has gotten a solar boost. ­This ­sport-focused smartwatch has an impressive 14-day battery life and can go two extra days if you spend a lot of time in the sun, courtesy of the solar panel hidden within the watch face. Like previous versions, it includes a built-in topo map of the entire U.S., music storage, smart notifications, and a payment app, and it has sensors for everything from GPS to pulse oximetry. It also tracks virtually any activity under the sun, including a long-­awaited new surf mode with a killer feature: if you’re shredding in front of a Surfline camera, you can watch a video of all the waves you caught. It’s expensive, but it just might be the best outdoor watch to date.

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Sponsor Content
WHOOP Membership and 3.0 Strap ($30/month)


This waterproof fitness tracker comes with a high-tech mobile app and premier membership services. With WHOOP you’ll receive 24/7 personalized insights on your training, recovery, sleep, and the daily stressors of life, so you can know yourself better and unlock your potential. For a limited time, use the code OUTSIDE at checkout for a 15% discount on your membership.

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Fitbit Sense ($330)

fitness tracker
(Photo: Courtesy Fitbit)

This sleek smartwatch represents Fitbit’s most holistic attempt at health monitoring. In addition to GPS and an altimeter, it features advanced heart-rate tracking that searches for signs of atrial fibrillation via a companion app and alerts you to high and low heart rates based on your personal threshold. It also includes sensors for body-surface temperature and for changes to the conductivity level of the skin, sometimes an indicator of physiological or psychological stress. The Sense uses these and other metrics, including sleep data and heart rate, to provide daily and real-time stress monitoring and potential early-illness detection.

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Filed To: Wearable TechTechnologySmart WatchesDesign and TechTools
Lead Photo: Courtesy the Companies

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