Know Your Tech: A Sports-Watch Jargon Buster

Suunto Spartan WHR Sports Watch

As athletic competition has become more mainstream so too has the technology we use to measure our progress. Suddenly every wrist seems to have a sports watch wrapped around it and conversations conversations about fitness are littered with terms like VO2 Max, Garmin, Strava, and discussions of heart rate zones.

Yet nothing about the ability to run, cycle or swim well gives you an automatic understanding of this jargon. Lots of people wear wrist-computers with more processing power than NASA needed to reach the moon, but they use nothing beyond the very basic measurements of distance and time. Not only is this a waste of some fantastic gadgetry, but it also overlooks the ways that your watch can actively help improve your fitness and performance.

This brief introduction to some of the key terms and features aims to demonstrate the value of a sports watch and help you get more from using one. Different watches offer a range of different features, but I’ve focused on the stuff that is common to most models.

Garmin Fenix 5 Sports Watch


Most people think of sports watches as a way to monitor running stats. Multi-sport watches, like the Garmin Fenix or Suunto Spartan ranges, allow you to map performance in a range of other sports, from popular alternatives such as cycling and swimming to niche activities like paddle boarding and assault courses.

Wrist-Based Heart Rate Monitor

This is the crucial feature of most current sports watches. A sensor on the underside of the watch measures pulses in the wrist to monitor how fast your heart is beating per minute and, therefore, how hard your body is working. It’s useful information for any aerobic sport, but especially running, cycling and swimming.

Garmin Forerunner 35 Heart Rate Monitor


One of the core features of modern sports watches is their ability to geographically map your activity. Older watches record geographical routes in the background and then allow you to upload this to apps after your outing. The current generation of tech often includes a map facility to help with navigation whilst you are out and about. This is done using GPS and/or GLONASS. GPS stands for Global Positioning System, the American satellite tracking system whereas GLONASS is the Russian version. There is a lot of debate about which is more accurate, and the only consensus seems to be that a combination of the two has a more likely chance of accuracy because it doubles the number of satellites being used. That’s why most current generation sports watches use both systems.

Garmin Fenix 5 Sports Watch

VO2 Max

One of the most commonly used (and misunderstood) terms used in running and cycling magazines, V02 Max refers to the maximum millilitres of oxygen you can consume per minute, for every kilo of body weight, when producing max effort. In simpler terms, it’s how much oxygen you deliver to your muscles you’re giving 100%. This has a direct impact on performance, especially in middle-distance activity that balance speed and endurance. Certain watches, like some Garmin and Polar models estimate this from the information gathered by the wrist-based heart monitor.

Polar M430 GPS Running Watch

HR Max

Simply put, it’s the maximum number of beats per minute your heart can manage when you’re going flat-out. Each person has an individual HR max that decreases with age. You can work out your approximate HR max by subtracting your age from 220. This figure is important in relation to your wearable tech as it forms the basis for how the watch monitors your heart rate zones (see below) during activity.

Heart Rate Zones

Heart Rate Zone display on Garmin Fenix 5X

Heart rate zones are a monitoring feature found in most of the new sports watches on the market. During a workout the watch tracks how long you spend in each heart rate zone, using your HR Max as a baseline. Each of these zones relates to an increasing level of workout intensity, ranging from ‘recovery’ (65-70% or your max heart rate) to ‘maximum aerobic’ (98-100%). You can review the amount of time you spend in each zone during a workout to improve your performance in different types of aerobic activity. For example, your marathon pace is generally what you can manage at 80-85% Max HR. The secret lies in increasing your speed whilst keeping your heart rate within this zone. If you can do this then you are working more efficiently. Sports watches are an incredibly useful tool to help you map this and target your progress.


This is an easy one: cadence is the number of steps you take per minute. It’s an important stat to consider in terms of running form and efficiency. Older sports watches needed a chest strap or extra components in your shoe to measure this, but newer models, such as the Garmin Fenix range record cadence directly from the wrist.

Garmin Foreunner 230

Chest Strap

I could write another entire blog explaining chest straps. To keep it clear: chest straps are an alternative way to measure heart activity. They feature an electrode pad that lies against the skin and record electrical information from the heart. Because of the direct proximity to the heart, chest straps are widely considered more accurate than wrist-based monitors. Modern-generation watches and chest straps are designed to work in partnership, with the strap uploading it’s data to the watch for an accurate picture of what your heart is doing mid-activity.


The majority of tech brands work in tandem with an app to provide a means of storing and analysing all of this performance data. These can be downloaded from Android or iOS app stores and work by synchronising your device (through Bluetooth or a USB cable) with a mobile phone, computer or tablet. Each brand has their own version of this facility. Garmin Connect is perhaps the best-known app, but Polar Flow, Suunto Movescount and others all work in similar ways. Most of these are also compatible with apps like Strava, which double-up as a activity record and social media channel. These third-party apps can be a great motivator, giving you stats on your own progress as well as friends'. They also give you way to keep in touch with fellow athletes and find clubs online or in the real world.

Garmin Forerunner 630

All sports watches have varying benefits depending on personal preference and intended use. The features above are the very tip of the iceberg in terms of what sports watches can do. In addition to these basic functions, some watches can measure statistics about sleep, about general calorie loss and even more technical details such as lactate threshold and vertical oscillation (another story)!

Hopefully, this short introduction will have given those of you unused to wearable tech a little more understanding of what it does and why it can be very useful to have it on your arm. Whether you are trying out a new sport or finessing your technique, wearable tech can give you useful info to structure your approach. More importantly, it can also help you establish personal goals and then enjoy the massive satisfaction of achieving them.

Garmin Fenix 5X Multisport GPS Watch

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Neil used to be a bookworm, an "indoor" type if ever there was one. After finishing a PhD he writes short stories about spooky places and odd people. Living in Switzerland, the Canadian Rockies and the north east region of the USA convinced him that there was something to be said for this whole outdoor thing. Now he runs everywhere he can, competing in races most weekends and endlessly planning the next great adventure to some far flung part of the world. Recent trips include Costa Rica, where he tried and failed to surf; Vietnam, where he almost got stuck in an underground tunnel; and back to Canada, where he came face-to-face with a bear. Watch this space for further updates on Neil's global bumblings and the occasional athletic success.

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