On the hunt for more advanced training insights? Picking up a dedicated heart rate monitor can help provide you with that extra hit of data you crave.
If you're an iPhone owner, there's plenty of options out there and now most GPS sports watches can do the job, but we know not everyone wants to spend big on a wrist-based companion. Plus, there's still plenty of question marks over data accuracy as well.
Read this: Learn to train with heart rate zones
For those looking for a package that covers heart rate zones and more, you can always go for a chest strap, a pair of smart headphones or even a headband to do the job for less.
Here's our pick of our favourite heart rate monitors that play nice with your Apple smartphone.
Wahoo Tickr X
We're big fans of the Tickr X, thanks in large part to its ability to store 16 hours of workout data without being tethered to your iPhone.
This means you can transfer all the data you've garnered once you've finished exercising, which can also include those pesky spinning sessions thanks to dedicated motion analytics.
The companion app isn't winning any awards for its complexity, but does allow for a breezy link-up with the strap and gives you a clean interface from which to control and view your workouts.
Wareable verdict: Wahoo Tickr X review
Like its older sibling, the Polar H7, the H10 is one of the strongest sensors out there. The iOS-friendly strap offers a modified design, adding silicone friction dots to help keep the strap in place, and is noticeably more comfortable to wear when exercising.
It uses the same ECG-style sensor that detects the electrical activity of the heart to deliver your BPM readings, though a fresh measuring algorithm and extra interference-preventing electrodes help improve accuracy even further.
What's handy about the H10 is the waterproof smarts, which mean you can take it for dips in the pool. And while its internal storage only allows for one training session, this is still a handy backup in case your iPhone loses power.
Jabra Sport Pulse Special Edition
Heart rate monitoring headphones are a thing now and Jabra's in-ears are some of the best in the business at churning out the workout intensity data.
Wareable verdict: Jabra Sport Pulse Special Edition review
Moving the tracking to the ears means the Pulse Sport has the ability to improve the accuracy of heart rate readings plotting average, peak heart rate and intensity zones.
It also packs in decent battery life, a series of sports tracking modes and it'll even let you do a VO2 Max test to assess your current state of fitness.
Moov HR Sweat
After it brought real-time coaching smarts to the original Moov and the Moov Now, the company's HR Sweat provides the next piece of the puzzle. The device is essentially a small circular sensor that sits inside a silicone case, which itself fits inside a sweatband.
This is still an optical sensor, but it works well for those who want to track data from the head. And according to the folks over at Moov, positioning the sensor to the high temples on the side of the head, where the skin is thinner and the blow flow is increased, also reduces sensor movement and makes for more reliable readings.
Wareable verdict: Moov HR Sweat review
Like its siblings in the Moov stable, the HR Sweat is able to sync up with your iPhone to let you store workouts within its companion app.
Tracking your heart rate through a monitor is one thing, but the MyZone MZ-3 also allows you to gamify the process.
Whether you're running, swimming, cycling or even rowing in the gym, the device will take your readings and project them into a points system. This isn't as basic as simply rewarding high rates, either, with MyZone able to understand your effort levels and provide an accurate picture through its companion app.
This takes the great heart rate game a step further, too, by offering league tables, personal goals and challenges for you to take on.
Like the Wahoo Tickr X, the MZ-3 has storage for 16 hours of data, meaning your iPhone doesn't always have to come buckled along for the ride.
If you don't want the burden of a chest strap but you also don't feel comfortable wearing something on your head, or need a pair of headphones, the Scosche Rhythm+ is a heart rate monitor that can be strapped to your forearm or upper arm.
It uses the same optical, light-based sensors that you find on pretty much all wrist-based trackers, meaning there are some minor questions over accuracy, but it's a handy option for those who want to export data to the likes of MapMyRun on their iPhone.
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