Mio FUSE Heart Rate Monitor Wristband Watch and Activity Tracker
|Finally a heart rate monitor that doesn’t have to be worn on your chest! And it works!!
Mio Global released its first heart rate monitor wrist watch, the Mio Alpha watch, in 2012. It was a huge break through in infrared heart rate monitor technology for the wrist strap as it measures in the same manner as the finger tip monitor you may have used at the doctors office or hospital. The challenge was getting this to work while performing strenuous activity such as running. Somehow they figured it out. An electro-optical cell senses the volume of blood under the skin. From there, sophisticated algorithms are applied so that the heart’s true rhythm can be detected, even during high intensity workouts.


This is by far the best option I have encountered for infrared heart rate monitors. If you’re not familiar with the technology, it’s a challenge to get this to work while performing any physical activity and typically the more aggressive and active you are, the less accurate they become. They work by shining a green LED light onto your skin and measure the blood flow through the skin and determines the heart rate. They typically have to fit tight against the skin and keep out all ambient light to improve the accuracy.
The FUSE device itself is made of a single piece of stretchable rubber like material that has the infrared module built into it. It’s elasticity allows for a comfortable snug fit without compromising motion to the wrist or cutting off circulation or impinging any nerves. Truthfully I think the material is one of the key factors in this working so well. I’ve also noticed the the infrared sensor and green LEDs are not protected by a “glass” or plastic shield. They do appear to be protected with an epoxy like coating. Also key in my opinion to improve reading accuracy.
Quick Specifications.
- Built-in accelerometer to capture steps, calories, distance, and pace
- Optical heart rate monitor, for EKG-accurate heart rate without a chest strap
- Configurable heart rate zones
- 5-color LED and vibration alerts to indicate heart rate zone
- Chronograph timer
- Offline storage of 2 weeks of daily activity data and 30 hours of workout data
- Water resistant to 30 meters
Unboxing
Testing
Ok. I’ve been running with this now for about a little over a month. I’ve logged well over 200 miles with it and have been very satisfied. It’s such a great feeling not having to strap the uncomfortable chest strap on and deal with the skin abrasions inevitably received on long runs. I did not have to shave my wrist or use any coupling gel or wet the sensors. It just works. You do need to make sure the placement is just proximal or above your wrist bone (ulnar styloid process) and if it’s not snug enough it can slide and cause signal inaccuracy.
It does not record your heart rate all day long as many activity trackers do. It will if the heart rate sensor is activated and a session is started be pressing go. Otherwise if you don’t start or lock in the sensor it won’t record your HR. The watch will record steps, total daily distance, calories, and does display time. There are three buttons (areas not true buttons) on the screen to scroll through the data fields. These areas are only active when the watch is in a horizontal position on your arm to prevent accidental triggering. Perfect if your scratching your back or wiping off sweat. You won’t stop your timer.
One issue is you do need a smart phone to use this device. In order to change any of the setting, and even activate it, you need to download the MIO global app (Android or iOS) and connect to the FUSE through Bluetooth. One of the settings I immediately changed was “keep display on”. This will keep the LED light display turned on when the heart rate monitor is activated otherwise the display will turn off until the sensor is tapped to turn it back on. I usually keep it on the heart rate display.

It does not have a GPS, but the built in pedometer does record the distance and also measures your pace. It’s about as accurate as a pedometer can be I guess. I don’t run with one so I really don’t have anything to compare it to. I did notice it was a bit off in terms of over calculating the distance a few times when running outside. When running on the treadmill it seemed to under-calculate.

Setting up
Before using. You need to pair with your smartphone. It’s pretty simple although I had one unsuccessful attempt which I’m not sure why. I turned Bluetooth off and back on on my iPhone and it paired fine.

Heart Rate
The device will function as a typical activity tracker counting your steps and calories, but will only recorded heart rate when the infrared sensor is turned on. The sensor is turned on by holding the central button until the watch vibrates. It will then display find until the heart rate is located.
One of the settings I adjusted (through my iPhone) was the keep display on function. This way, when the infrared sensor is turned on or activated, the display will stay on. At this point you can either start an activity by pressing the central button, or simply
Clearly one will purchase this simply for heart rate monitoring. There are several ways you can utilize the heart rate monitor for training. You can set the zones for either 1 zone mode or 5 zone mode: The zone alert tracks your target zone and will notify you when you are above or below your target HR zone. The Maintence zone monitors 5 specific zones and a rest zone. With these zones you will see a color LED dot light up that is specific to that zone. This can be adjusted to be stay lit, blink every 1 second, or blink every 2 seconds. You can also set a vibration alert to notify you when you are out of a specific zone. In the one zone mode it will vibrate when you are out of your training zone. In the 5 zone mode, it will vibrate each time you switch zones. The directions say that you should avoid wearing the Mio FUSE in extreme cold weather as it’s not as accurate. I had not issues in 10 degree F weather with the FUSE worn under my shirts and jacket. I then kept my GPS watch on the outside to display my HR. Worked perfect.
It does seem that the longer I run at a given time, the more likely it is to lose connection or heart rate reading. I’ve noticed when it does this It will skyrocket from what would have been my training heart rate of 140 to Andy abnormal reading of 170. I’ve found that by holding my wrist still by either holding the bar on my treadmill or just extending my wrist and not swinging my arm, the sensor seemed to find my true heart rate again. I also found that by turning off the sensor and then turning it back on to again find your heart rate it did catch again. This didn’t seem to happen too often and it really wasn’t too abnormal from what I have encountered with chest straps. It also seemed that even if I let it go and did nothing it eventually reconnected to my true heart rate.
Battery
The battery charges by connecting to the USB cable that magnetically (not a real strong connection) attaches to the watch. I’ve noticed it’s pretty fast. Somewhere around 2 hours I would say. The charge will last up to 6-7 days if you are using the heart rate monitor option around an 1 hour per day. The instructions say the battery will last about 365 charges.
Summary
This is basically the only paragraph you need to read. If you are wearing a chest strap now to monitor your hear rate. Ditch it. This is a great way to track your heart rate without the irritating chest strap. I found it to be very accurate and comfortable to wear. If you’re attached to a specific Garmin or similar GPS watch you can still wear the Mio FUSE and transmit the HR via the ANT + signal the GPS watch. You can even wear them on the same wrist. I have tried to wear the watches on opposite wrists and had issues with ANT connectivity. This was avoided by placing them on the same wrist. It’s not the most comfortable situation but if you need both watches on, it will work. Otherwise, just wear them on separate wrists and read your HR not he FUSE with the understanding that it may not record on your GPS watch if paring is spotty.

Overall
Not my favorite running “watch”, but they’ve cracked the code for infrared wrist based heart rate monitoring. It’s been about six months now since I’ve been wearing this and it’s definitely the most accurate I’ve worn. It has an extremely comfortable band that can be made snug enough for the infrared signal to work properly. It’s priced reasonably in my opinion at $149 and is available here on Amazon.
Feel free to reach out with any questions regarding this watch!!
Thanks!