Best Fitness Tracker for Interval Training

Best Fitness Tracker for Interval Training – The best thing I can say about Matrix’s PowerWatch 2 ($500) is that the recharging from body heat and solar power really works. I wore it for more than three weeks without having to recharge it. However, it’s huge and clunky. During my testing, the heart-rate monitor was inaccurate, and it was hard to change the display.

The app was beset by technical problems, and I constantly had to reinstall and reconnect the watch. For such an expensive watch, it was just too hard to use.


1.Garmin fenix

Pros & Cons

The Fenix series is a family of fitness trackers that pretty much has it all when it comes to outdoor fitness and adventure tracking. Stepping things up a notch, Garmin released the Fenix 6 range in August 2019, offering users a slight update in design and some welcome new features over the Fenix 5 Plus.

We always see some excellent discounts on sports tech on Amazon Prime Day, and we’d be surprised if this year’s Prime Day deals don’t include an offer on the Fenix 6. It’s a great opportunity to pick up one of the most powerful sports watches around at a bargain price.

2.Lintelek Fitness

Pros & Cons

Earning one of the worst scores overall, it’s easy to see why the Lintelek ID115HR failed to earn an award. This very bare-bones model doesn’t have a very impressive set of features when it comes to tracking overall health and fitness stats, scoring average at best in those evaluation metrics.
It’s not the most ergonomic or stylish and has an overall lackluster display that can be hard to read outdoors. However, its simplistic nature does make it fairly intuitive and easy to use, as there aren’t a whole lot of menus and settings to get lost in.

3.Withings Steel

Pros & Cons

Fitness trackers aren’t inherently attractive looking wrist wear, with many looking strange on the end of your arm – but what if all those tracking features were built into a watch?

The Withings Steel HR is trying to push the boundary of what we’ve seen inside a hybrid watch, combining a classic design with fitness tracking features. The strange thing is, we’ve seen almost this exact same product before.

Originally launched under the name of the Withings Steel HR, Nokia then took over the brand and renamed the product the Nokia Steel HR. Then Nokia fitness products were rebranded back to the Withings name, so again it’s called the Withings Steel HR.


Pros & Cons

The Coros Apex is a breath of fresh air for endurance athletes that care about simple design, excellent battery life, and a great deal. While it doesn’t have preloaded layered maps or extras for navigation, it has all the features you need and none that you don’t.

It offers excellent battery life, a breadcrumb trail map, TrackBack, and sensors to measure barometric pressure, altitude, temperature, and heart rate. On top of that, GPS accuracy is one of the best. After testing it during open water swimming, trail running, and skiing, we are impressed at its performance, especially for the price.

5.Apple Watch

Pros & Cons

The Apple Watch Series 7 is Apple’s latest smartwatch, featuring a larger always-on Retina display, a more rounded design with a larger casing, improved durability, and faster charging, starting at a price of .

Announced in September 2021, the Apple Watch Series 7 is the newest Apple Watch in Apple’s lineup and it is at the start of its product cycle. Apple tends to release new Apple Watch models every September, and there is no reason to suggest that a new Apple Watch Series 8 will not launch next year.

There are early signs of Apple Watch Series 8 models with a number of upgrades and improvements, but since this is likely still around a year away, now is the best time to buy the Apple Watch Series 7.

Best Fitness Tracker for Interval Training – BUYER’S GUIDE

Step counting

Before heart rate monitors became standard, keeping track of your steps was the reason you’d wear a device all day, rather than just strapping one on for a workout. An accelerometer in the device senses movement and software translates certain movements into steps. It’s an imperfect method to say the least, as anyone whose fitness tracker has buzzed to celebrate a step goal while you’re sitting on the bus will know.

That’s not to say counting steps is pointless. Movement – steps or otherwise – is good and more movement is better, and it’s the little encouragements and challenges to induce you to move more and move regularly that can be beneficial to your health.

Heart rate monitoring

It was once a feature restricted to high-end trackers, but most wearables now offer optical heart rate tracking. Some will only record your heart rate constantly during activities and take periodic measurements throughout the day to preserve battery life, but we think you should expect 24/7 monitoring on anything that costs over £100.

With heart rate tracking comes a wealth of other information, including an estimate of your VO2 max and resting heart rate, both of which are good measures of your overall cardiovascular fitness. High-end sports trackers also use heart rate tracking to provide info on the effect of your training session and how long you should spend recovering afterwards.

Optical tracking is usually pretty accurate during day-to-day life, but is more hit and miss during exercise, especially intense workouts. That can be especially problematic when certain tracker brands offer training sessions to follow that rely on you working on certain heart rate zones. Getting a tight fit with your tracker can help, but don’t expect miracles – if you want more accurate heart rate tracking it’s wise to link your device to a chest strap via Bluetooth or ANT+ if possible.

ECG Measurements

There are several fitness trackers available now that can take a medical-grade electrocardiogram (ECG) measurement from your wrist, which you usually do by holding your finger against one part of the device for 30 seconds. These ECG scans can detect atrial fibrillation, ie an irregular heartbeat – a common condition, but one that you will want to get checked out by your GP if a device does detect it.

Watches with the ability to take an ECG reading also often be able to monitor your heartbeat proactively to detect abnormally low or high heart rates, or prompt you to take an ECG if they spot any signs of an irregular heartbeat.

ECG-enabled fitness trackers require a CE mark in the UK and Europe, which means some devices that can technically do it don’t offer the feature yet while this certification is pending. Those that already have a CE mark include the Apple Watch, the forthcoming Fitbit Sense, Fitbit’s Ionic and Versa smartwatches via a third-party app FibriCheck, and the Withings ScanWatch. The Samsung Galaxy Watch 3 and Galaxy Watch Active 2 devices are awaiting formal certification.

Frequently Asked Questions

Fitness trackers collect and present all kinds of data, including the number of steps you walk in a day, the kinds of activities you do, the intensity of your workouts, and how well you sleep. But how accurate are they? It depends. Although fitness trackers tend to measure some activities well, they measure others quite poorly—including all-day step count. (On that note, the often-lauded touchstone of 10,000 daily steps seems to be arbitrary at best, though moving more throughout the day is rarely a negative.)

Health apps and wearables collect a raft of data, which isn’t regulated or legally protected in the same way that other health data (say, from a visit to a doctor) is (by HIPAA).


We’ve tested dozens over the past four years to bring you these picks. Not quite what you’re looking for? Check out our guides to the best smartwatches or best running gear.