It used to the be reserve of elite athletes and amateur fitness geeks but, thanks to the likes of Mio, Adidas, Apple and the rise of wearable tech, heart rate monitoring is going mainstream.
Give it ten years and clocking your pulse will be as common place as checking your Twitter stream. But as the tech manufacturers rush to stick bpm sensors into products, finding the best heart rate monitor for your own personal needs is getting increasingly tricky.
There's a huge range of options, offering varying levels of convenience, accuracy, comfort and compatibility. Not to mention cost. But fear not, our fitness tech expert Kieran Alger, has some handy tips on how to buy a wearable that'll win your heart.
Do I need to monitor my heart rate?
It might sound like a stupid question but, if all you want to do is be a bit more active, then heart rate monitoring probably isn't really necessary. If you want to keep tabs on you average heart rate outside of exercise, then something like the Withings Smart Body Analyser Wi-Fi scales that clock your heart rate each time you step on to check your weight, might be more appropriate.
Alternatively for general heart health, there's always the find a pulse, time thirty seconds and count. Granted, it's old school, but it's also free.
There are general health benefits to tracking heart rate but where it really pays dividends is when applied to training. Monitoring your bpm during any workout session enables you to ensure you're exercising at the right intensity to achieve your fitness goals.
It also helps you put together a bigger training schedule with the right combination of sessions at the right intensities, ideal for returning from injury or preparing for something like a marathon.
How much should I spend?
You can spend anywhere from $40 for a basic chest strap that'll pair with smartphone apps like Strava and Endomondo; right up to $600 for a top-of-the-range fully featured GPS and heart rate tracking watch, with built-in optical heart rate sensors (OHR). How much you spend will largely depend on how serious you are about your training.
If you're at the top end trying to shave seconds off your personal best then you'll probably benefit from the depth of data and accuracy you get from a more capable Garmin or Polar watch paired with a chest strap. But if you're after some general fitness gains then there are plenty of wallet-friendly options that'll help you track your progress without costing a fortune.
There are also chest straps like the Wahoo Tickr X that bridge the gap, pairing with a your smartphone to offering some quite detailed analysis without the hefty price tag.
What type should I buy?
Just like any tech purchase, there are some simple questions you can ask yourself to help narrow down your search.
Do you want something that enhances your existing fitness tools that's compatible with your preferred smartphone app or other devices? Or are you starting with a clean slate? Do you care more about comfort, convenience or accuracy? How long do you need the battery to last? An hour in the gym or a twelve hour ultra marathon? Do you need to see your heart rate data in real time? Do you need virtual coaching or are you happy to decipher your data?
All of these things are worth thinking about before you being your search.
Which method is most accurate?
There are three more common methods for tracking your heart rate. There's the classic chest strap, devices that do optical heart rate (OHR) from the wrist and a finally a new trend for headphones that track your pulse from inside your ears.
Chest straps have been around for a long time and despite being much maligned for its lack of comfort and convenience, the trusty strap is still held up to the the most accurate way to track heart rate with brands like Polar and Garmin tending to prefer pairing one of these to their watches.
When it comes to accuracy, optical heart rate has a lot to contend with. There's the positioning for a start. It's location away from the heart means there can be a delay in reading changes in bpm.
In the tests we've conducted, it not only takes OHR longer to settle down but it can also be slower to latch on to those times when you've dropped to a walk in workout.
There's also a question of light interference. If wrist monitors aren't worn tight enough to the skin, and in the correct position, they can struggle to get an accurate reading as light leaks in and affects the LED.
That said, the chest strap is under fire. And it seems a lot of us are happy to sacrifice a little accuracy for the convenience of one device that can do it all.
Brands like Adidas, Apple, Tom Tom and now even Garmin pushing devices that track your bpm from your wrist using optical heart rate.
It's the same principle - why pack two devices into your gym bag when you can have one - that's also seen Jabra and LG build optomechanical heart rate tracking sensors into their earphones. The theory being that if you tend to listen to music while you work out, there's a great opportunity to have real-time coaching delivered through the same headphones.
Want more data?
Even chest straps are getting smarter. Bluetooth Low Energy has enabled wireless links with smart phone apps and GPS watches, while brands like Wahoo have added accelerometers, to make its Tickr X capable of tracking movement as well as BPM.
Chest straps pair pretty readily with gym machines like treadmills whereas earphones and wrist monitors rarely do.
Essential reading: Best heart rate monitors
You could argue that if you're wearing something like the TomTom Runner with its OHR sensor then you will be able to track your heart rate and indoor runs regardless, but as gyms become more connected, offering complete tracking tools like the Technogym MyWellness Cloud, there is a small benefit to investing in a chest strap over a watch.
Going into the water?
Choose a chest strap. Built-in wrist based trackers don't fare well in the pool.
Swimming and heart rate tracking have had a rocky relationship. The devices that use OHR technology struggle under water thanks to inference. The pressure a watch is under when you're arms are moving in and out and through the water not only causes the watch to move but it can also get between the sensor and your skin, breaking the beam and giving inaccurate data.
Essential reading: Check out our running hub for tips and tech
Garmin has just launched a chest strap that works in the pool and triathlon specific watches like the Polar V800 link up with the Polar H7 chest strap to also offer underwater HR skills. The added benefit of the Polar H7 is that it also works on its own and can be paired with other smartphone apps.
Want to spot an incoming cold?
Go for a heart rate monitor that makes it easy to track and compare your resting heart rate on a daily basis.
While it's often pitched at fitness types, bpm tracking isn't only for people who want to get the most from their training sessions. Monitoring your heart rate regularly during the day can be a great indication of well being, as well as a red flag for potential health problems.
Essential reading: Best GPS running watch
A raised resting heart rate, for example, can be a sign that you might be about to get a cold. The best option we've seen for this is the Apple Watch. Its wrist sensor clocks you heart rate every ten minutes making it easy to get a resting heart rate reading when you first wake up. Providing you wear it to bed of course.
Need help deciphering your data?
Opt for a heart rate monitor with colour-coded real-time zone training.
Gathering heart rate data is one thing, knowing what it means for you is another entirely. If you're still working on getting that sports science degree then you'll want to opt for a device that makes interpreting your heart rate info easier.
The new Garmin Forerunner 225, the Adidas SmartRun, the Polar M400 and V800 all do this. They'll not only show you your current heart rate but also what heart rate training zone you're in. Some of these will even vibrate if you drop out of your target zone.