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The 4iiii Viiiiva Heart Rate Monitor is a very clever little device that is great for Zwift users on Apple TVs. The ability to record an activity to the unit itself is a neat touch that might come in handy, and the data captured has been consistent with no dropouts. There are cheaper options out there, however, as you can see in our best heart rate monitors guide.
Buying a heart rate monitor might not seem like the most exciting purchase to make but getting one that will work without fuss and has a few useful features is how you ensure that you'll be able to train consistently. The Viiiiva – I'm typing Viva from now on, sorry 4iiii – is a heart rate monitor that just works. It continues to feature the ANT+ to Bluetooth Bridge function that we loved in the last one we reviewed, is able to store 65 hours of workout data for when you're in a technological pinch and it hasn't missed a beat. Sorry.
Pairing this unit with a selection of cycle computers and watches was a piece of cake. The ANT+ connection is quick to establish and has then been rock solid during testing.
You can also use the Viva as a bridge to link any ANT+ only sensors to a Bluetooth-only device. Many users have also commented on how useful this is when you're limited in your Bluetooth connections, such as when Zwifting on something like an Apple TV. Seeing as I don't have an Apple TV, I had to cart a few sensors over to a mate's house and set them up in his front room. The process was very simple, so if you need the function, it works well.
Another clever feature is the Viva's ability to record your training data. So, if you turn up to a ride without your head unit, you can connect your power meter to the Viva and record a workout from there. You won't get any GPS data, but at least your training will be logged. I used it once to try it out and, thanks to 4iiii's easy-to-use app, it is a very simple process.
Adjusting the size of the strap to fit your chest is easy and after that, it seems to stay put, not falling down when I went for a very occasional run. It's also very comfortable, which is nice on longer rides.
Most importantly, however, is that the data seems to be perfectly reliable. I had a few dropouts on my first ride, but since then, I've experienced zero issues with the Viva.
The Viva runs on a single CR2032 battery and 4iiii claims a battery life of 160 hours. It's quite tricky to rack up that amount of time on the bike for me these days but seeing as I've been putting this review off for far too long, I did get to the end of a battery. The switching is really simple, however, so this isn't an issue.
At £59.99, this is a fair bit more expensive than the £39.99 Wahoo Tickr heart rate monitor that Dave reviewed, and which boasts a claimed battery life of 500 hours. However, the Tickr doesn't allow you to do the fancy ANT+ to Bluetooth Bridge trick.
If you would like the ability to bridge ANT+ sensors to Bluetooth devices, or you might use the built-in data recording, then the Viiiiva would be worth the extra money. Otherwise, you're simply getting solid and reliable heart rate data.
Expensive, but the Bluetooth Bridge and other features make it a great choice
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road.cc test report
Make and model: 4iiii Viiiiva Heart Rate Monitor
Size tested: One size
Tell us what the product is for and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
"Viiiiva is so much more than your standard Heart Rate Monitor. While storing 65 hours of workout data, Viiiiva also acts as an ANT+ to Bluetooth Bridge. You can broadcast your ANT+ devices to your bluetooth devices all through your Heart Rate Monitor - perfect for foot pods and Zwifting on Apple TV."
Tell us some more about the technical aspects of the product?
Measurement Type: ECG-Electrocardiogram
Operating Temperature: 0 to 50°C (32-122°F)
Storage Temperature: -20 to 60°C (4-140°F)
Battery Type: CR2032 lithium ion coin cell
Battery Life: 160hr
Waterproof Rating: IPX7
Radio Frequency: 2.4ghz
Strap: 57 to 132cm (23-52in)
Length: 65mm (2.6in)
Width: 37.4mm (1.5in)
Depth: 11.2mm (0.4in)
Module Weight: Pod: 14g (0.5oz), Strap: 33g (1.2oz), Total: 47g (1.7oz)
Communication Protocols: ANT+, Bluetooth
Activity save duration: Up to 60hr
R-R Interval Unit: 1/1024 sec
Tell us how the product performed overall when used for its designed purpose
It delivered reliable heart rate data without dropouts. So, perfectly.
Tell us what you particularly liked about the product
The Bluetooth Bridge function is easy to use and very useful.
Tell us what you particularly disliked about the product
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
Higher than the Wahoo Tickr. But that doesn't have the Viiiiva's features.
Did you enjoy using the product? Yes
Would you consider buying the product? I'd probably go for a cheaper unit
Would you recommend the product to a friend? Yes
Use this box to explain your overall score
It captures heart rate data accurately and without dropouts. The Bluetooth Bridge feature is going to be very useful for Zwifters using an Apple TV and the ability to record data to the unit itself is a bonus. But you can go cheaper.
About the tester
I usually ride: Specialized S-Works Tarmac SL7 My best bike is:
I've been riding for: Under 5 years I ride: Most days I would class myself as: Expert
I regularly do the following types of riding: road racing, time trialling, cyclo cross, commuting, club rides, general fitness riding, I specialise in the Cafe Ride!