The main job of a chest strap heart rate monitor (HRM) is simple: to track your heart rate more accurately than optical heart rate monitors like the ones found in fitness trackers. The best heart rate monitors are accurate and sometimes offer more features on top of this tracking.
Unfortunately the Hammerhead HRM has no extra features and during my testing it wasn’t as reliable as other chest straps – in fact its tracking frequently gave wildly incorrect readings.
Hammerhead Heart Rate Monitor Review: Price And Availability
The Hammerhead HRM is available now and costs $64 in the US and £54 in the UK. That’s less than the best chest straps from Polar, Garmin and Wahoo, though those straps offer more features than heart rate tracking. Some straps like the Polar H9 are available for the same price as the Hammerhead.
Design
The Hammerhead HRM is light, with a sensor that weighs 15g. The pod attaches to an all-fabric strap, with two rubber electrodes to detect the ECG signal and track your heart rate. This soft fabric makes the strap comfortable to wear for long periods, and it’s easy to adjust the length using the buckle. The strap uses a hook clasp to secure it in place, and it’s waterproof to 30m and washable. The Hammerhead HRM offers Bluetooth and ANT+ connectivity, and you can connect two devices at once via Bluetooth (ANT+ is unlimited).
How I Tested This Heart Rate Monitor
I have been using the Hammerhead HRM to track all my workouts over the past few weeks, including 15 runs, plus several strength workouts and a yoga session. I connected the strap to three sports watches during that period. I have also tested most of the best heart rate monitors on the market.
Sports Performance
On my first run with the Hammerheard HRM I noticed that it was struggling to pick up my heart rate for the first few minutes. I assumed that I had not wet the strap thoroughly enough before starting and gave it the benefit of the doubt, because after around five minutes it did lock on to what seemed the correct heart rate for the rest of the run.
Unfortunately, this has been a problem on several runs since – no matter how well I prepare the strap before the run by wetting the electrodes. The first five to 10 minutes are a lottery as to what the HRM will read, and it’s usually too high.
I also saw several incorrect drops in my heart rate during workouts while using the Hammerhead, and these sometimes lasted long enough for my Garmin watch to change the classification of the workout, moving it from a tempo to an easy run or similar. This affects the overall training analysis offered by the watch.
The Hammerhead HRM works well 80-85% of the time. However, the reason I’d wear a chest strap (which is more of a faff than just using the heart rate monitor in a watch) is near-perfect accuracy, and that is what you will get from the best straps like the Polar H10 and H9, or the Garmin HRM-Pro Plus.
If a strap is throwing up errors even just in every third run or cycle, it quickly defeats the point of using it, and the Hammerhead HRM was too unreliable in my testing to make it worthwhile.
Battery Life
The Hammerhead HRM uses a replaceable CR2032 coin battery and the battery life is meant to offer 900+ hours of use, which is a lot. That’s more than double what you get from the Polar H10, for example. Battery life is a strong point, though I noticed the sensor lights flashing occasionally when the strap was not in use, which may drain the battery outside of workouts.
Is The Hammerhead HRM Worth It?
If you can’t rely on a chest strap being accurate 99% of the time, it becomes superfluous kit, since the only reason to wear them is for greater accuracy than on the optical heart rate monitor on fitness trackers.
As such I’d steer clear of the Hammerhead strap. It’s accurate most of the time, but makes mistakes more frequently than other chest straps. The Polar H9 is around the same price and provides better reliability in my experience, so that’s an easy alternative to recommend.
If you’re happy to spend more, the Garmin HRM-Pro Plus is an accurate strap that also offers running technique stats when linked to a compatible Garmin watch or bike computer.