Do not be fooled: while both Polar and Wahoo offer heart rate monitors you can wear on your upper arm, it was Scosche who did it first – and proved that moving the sensor technology a little higher up had the potential to deliver accuracy on par with chest straps.
The Scosche Rhythm+ is still considered one of the best heart rate monitors out there, and with the arrival of the Rhythm24, the company wants to continue offering that accuracy for anyone still not satisfied with what wrist-based monitors offer up, or who simply don't like wearing a chest strap.
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It still employs light-based, optical sensor technology similar to what you'd find in an Apple Watch or a Fitbit Versa – the difference here is that Scosche's PerformTek sensor employs green and yellow optical sensors to ramp up that accuracy on all skin tones.
It's ANT+ and Bluetooth Smart-compatible so you can use it with a whole bunch of third party fitness apps, sports watches and sports equipment. It also has dedicated modes for running, cycling, duathlons and triathlons, and will even let you tap into heart rate variability monitoring to offer insights into stress and recovery time.
It's also going to have big appeal for swimmers, too, as it's IP68 certified, meaning you can take it in the pool for your swims and still access heart rate monitoring. And in case you were wondering, that's something neither the Polar OH1 or the Wahoo Tickr Fit HR armbands can offer.
We've been fortunate enough to get some play time in with the $99.99 Rhythm24, so before we give our full verdict on the HR armband in a few weeks' time, here's what we're making of Scosche's new heart rate monitoring armband so far.
Bigger than the competition
Scosche might have been first to the party, but the design has certainly not evolved that much from the first version. You still get that elasticated strap that sits around the upper half of your arm, just below the elbow. These bands are interchangeable and cost $14.99 if you fancy a splash of colour, with black, pink, blue, purple and green options available.
That holds the tracking module in place, which has now inherited an additional button that's used to record a session. You can store workouts onto the wearable and then sync it later, which is a really nice touch if you just want to work out with the Rhythm24 and nothing else. Well, no other tech, that is.
Scosche Rhythm24 (left) and Polar OH1 sensor (right)
There's a central LED array in between the multi-function button and the record button, and that's your way of knowing a few things without looking at your phone or whatever device you have paired to the armband. The first is displaying heart rate zones, with blue signifying zone 1, green for zone 2 and a rapid red flash indicating you're in zone 5. You can also input resting heart rate and maximum heart rate in the companion Rhythm Sync app (iOS only) to make sure heart rate zones reflect your current fitness levels. The other use is that it will tell you how much capacity is left on the device to store workout data, with the ability to quickly clear memory from the wearable before you start recording again.
The big appeal of a HR armband over a chest strap, much like a watch, is that it's more comfortable to wear, and thankfully that is the case with the Rhythm24. While it sits bigger on the arm than the Polar OH1, we did find that it was a snug fit, whether we were running outside, on a treadmill, on the rowing machine or having a weights session. The key is to not wear it too tight, so as not to restrict arm circulation, and the adjustable strap can ensure it's not going to slip or move around. That simply hasn't happened in our time with it, so that's definitely good news.
Let's go running
The Rhythm24 is built to be used for a variety of sports, so inside the companion app you'll find dedicated profiles for a range of activities. We've focused on running to kick things off but we are definitely intrigued to find out how well it works for swimming. Unfortunately, we weren't able to test that out just yet, due to some issues that we're told have ben rectified, but we will be running the rule over its pool monitoring skills for the full review.
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As far as getting things going is concerned, it's really easy. We used the Rhythm Sync app to pair and sync data and pairing works pretty much instantly. What you'll get in the app is a live BPM reading along with your current heart rate zone and the current sport profile. It's then simply a case of turning the device on by holding down the button with the big 'S' and then hitting the record button.
Accuracy is what we were looking for and it looks like it'll be more of the same with Scosche's latest armband. We put it up against the wrist based heart rate monitor featured inside of the Suunto 3 Fitness, which is also powered by the same Valencell tech as the Rhythm24, and the heart rate monitor support on the treadmill. High intensity interval training is where most wrist based monitors fall short, and much like our time with the Wahoo Tickr Fit and the Polar Oh1, the Rhythm 24 delivers the goods. It was never more than 1-2 beats out for accuracy and unlike the wrist-based monitor didn't overestimate maximum readings or take that bit longer to drop back down to our resting heart rate between resting periods in some interval running training.
Rhythm Sync app (left and centre) and workout shared to Strava (right)
Once the session is over, it's time to head back to the app, where you'll need to open up the dropdown menu to sync your workout. After a quick scan for the armband, it'll pull out any of the workouts stored on the device, noting the data, time and file size. From there you can choose to export or share to compatible services, which includes Strava, Apple Health and Training Peaks.
Once you've configured your sharing options, sending workouts to other apps is a lot easier to do. Once you've compiled a large number of workouts on the device, I can imagine syncing workouts being a bit messy, so it'll definitely pay to sync regularly and clear up workouts you no longer need to sync. The Sync app itself is pretty basic, because it's simply built for syncing. While it does offer the ability to store your details (weight, height, heart rate limits), the onus here is really just to push your data to another health and fitness app.
We obviously have a lot more testing time to put in with the Rhythm24 – particularly to find out how it fares in the pool, which could make this massively appealing for triathletes and swimmers. With a claimed one-day battery life, we'd also like to know how many tracked sessions you can get in before reaching for the charger. There are also features like the HRV-based training insights and other dedicated sports modes that make this a more feature-packed alternative to Polar and Wahoo's HR armbands.
It's a case of so far, so good, at least on the accuracy and comfort departments, the two things at the very least we'd hope Scosche would deliver on. While it's not the best-looking device you'll ever see and we'd probably like it to be just a little smaller and more discreet, there are some really nice touches that should make the Rhythm24 a valuable training tool for beginners or serious athletes who hate chest straps or don't trust wrist-worn HR monitors. When you consider the price and what you're getting for your money, it looks like Scosche has come up trumps once again with its latest HR armband.
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