Polar OH1 + Waterproof Optical Heart Rate Sensor with Swimming Goggle Strap Clip and Armband – HR Monitor with Bluetooth, ANT+

I have only worn this on hikes, runs and jiu jitsu sparring. If you use the arm strap and place it on the inside of your bicep it is pretty comfortable and after a while you forget it is there. It is a bit fidgety to use at first especially trying to turn it on and off, also the app is a little clunky and you can accidentally lose your data quite easily. Now that I'm used to it, it's effortless to use, just turn on, open the app and press start. I haven't tried it in the water yet, my son is a club swimmer so I'll let him give it a good try out. Posted a screenshot of info from a 2 hour Jiu jitsu session. It's good value for money, build quality is robust and comfortable to wear and easy to charge with good battery life. Would recommend.

Comfortable to wear, correlates well with BP and oximeter readings. Very easy to set up, works seamlessly with Waterrower (ANT+) and polar app. Battery life seems very good, rarely charge and never been flat. Syncs well on PC with Polar account

Like a lot of people I've become more active over lockdown running much more regularly and trying to understand how best to train for the best results. One of the approaches I read about was heart rate training which basically suggests that running at certain levels of intensity based on your exertion as measured by your heart rate is an effective training method. I also read that wrist based heart rate trackers built into fitenss watches are not very accurate and that a specialist device like this can give you better data, hence me going for this device. It works in conjunction with the watch, effectvely superseding the built in heat rate monitor.The Polar OH1+ is like a thick £1 coin in size and it fits very securley in the cradle on the provided armband. Once charged (it uses a plastic cradle with usb connection) it's easy to operate for it's basic purpose. A simple 2 second press turns it on, the thing lights up green and it's ready to pair to a device. My watch has picked it up within a second or so each time so far (I've had this a good few weeks now) and I've had no issues with it in that regard.You can wear the OH1+ a few ways, as an armband, on the forearm, on the leg or on the temple for swimming. I've used it as an armband and on my forearm and found it comfortable in use.In use I have noticed the instantaneous HR data displayed on my watch is more promptly updated. In other words, I can see my HR rise and fall much more quickly in relation to my effort than my watch alone could manage, which sometime seemd to lag a good 20 - 30 seconds sometimes. With the OH1+ providing the data, when I slow my pace or walk during a run I can see the HR falling off within seconds which just makes it easier to stay within the HR zone I'm aiming for.I've only used the OH1+ when it's been hooked up to my watch but it can record HR data for a number or workouts in isolation that can then be uploaded separately. I can't comment on how well that side of things work but the functionality is there. I've also not used it for swimming so please check out other reviews if that is your intended use.For runners though, with a smartwatch already, looking for an upgraded HR sensor this seems to do a decent job. It's not hugely expensive and seems to prrovide more responsive data and has made managing my runs easier as a result. It's also been easy to use in this scenario, all I do is turn it on, it pairs to my watch and I'm away.

This has been a transformational piece of kit for me. I've ran/cycled with HR for years, had many different types of chest/wrist based straps, but this has been the most consistent and comfortable one ive ever used. As quick to pick up as a chest strap, and as accurate (I had an H10 and Tickr before this). The gamechanger is how comfortable it is, and not having that feeling of dread putting it on damp!!!!If there was one downside, it's the battery life isn't amazing, but unless you're doing ultras or IronMan, it should be more than sufficient

Excellent addition to a smart watch. It’s very small - not noticeable under a t-shirt sleeve and barely noticeable below one - easy to pair (with no need for additional software) very simple to use, appears to be very accurate, and unlike the sensors on my watch doesn’t suddenly stop reading just because i’m sweating a bit. Fully compatible with Apple Watch: just pair and play. Really pleased with this.

I really wanted to like the Polar OH1+, but it has too many drawbacks to recommend. The heart rate tracking itself is fairly accurate when it works, and the armband is comfortable. However, the connectivity is a nightmare—Bluetooth drops frequently, and ANT+ is hit or miss. Syncing with apps is inconsistent, and sometimes the device just refuses to connect.The swimming goggle strap clip is a nice idea, but in practice, it’s awkward and doesn’t always stay in place. Battery life is decent, but not amazing. For the price, I expected a more reliable device. If you need a hassle-free HR monitor, you might want to look elsewhere.

Not easy to connect to app, you have to turn app on first then the band. I found no matter where i placed the band on my arm sometimes it would be working other times which was more often I was getting low heart rate even though I was working out at higher levels of effort. Sent it back and getting chest band. The app is really good, but think polar should stop selling this band though as make me doubt there products! This was the second unit I had as the first one I had was even worse at reading heart rate.

Far more accurate than using my Fenix!