I have been testing the Mio Alpha. The Mio Alpha is pretty unique as it is a belt free pulse monitor rather than a heart rate monitor with a chest strap. The Mio Alpha works by using light to sense the blood flow in the skin beneath the watch, so as you can see below the tech part is on the back of the watch. There are phone apps which use the camera to do the same thing but in a much cruder way. The Mio can always display your HR whenever you have the watch on, which is a bonus for those that forget their chest strap on occasion. The Mio is broad but low profile so quite comfortable and easy to wear with all types of sleeves. Looks are distinctive with retro block LED display.
The Alpha works really well as long as the watch is nice and snug against your wrist, which wasn’t a problem as the broad rubber strap was very comfortable for me but could be a problem for those with very slim or narrow wrists. The heart rate data produced seemed consistently accurate. At on point the watch was resting on my wrist bone and had a gap underneath causing my heart rate to rocket! If your heart rate is within your zone limits the watch flashed green or red if above or below, with optional tones to alert you to this. I found the rest of the functions very basic, there is no downloadable log file of your exercise, just a brief summary on the watch which is over written the next time the stopwatch is started. Although the watch comes with a usb cradle for charging there is no actual computer connection. You heart rate data can be transmitted in real time using the ANT+ protocol on bluetooth to both iOS and Android phone apps but only in real time as there is no memory as such. One of these apps like strava or mapmyrun might then have combined HR and GPS data recorded but it’s not possible without your phone. As I am used to downloading a full log file of my exercise from my Suunto Ambit I found this a little disappointing, although not everyone is interested in this data.
The Mio Alpha will appeal to those who dislike or cannot wear a chest strap whilst exercising (I didn’t test it swimming but this is one obvious area where it could do well). For me I found the rest of the watch too basic to justify the price of £175. There is no alarm or count down timer or inbuilt GPS for instance. If I was going to spend that money on a HR monitor and I wasn’t against the idea of a chest strap then there is better value to be had I think, but for those who want to be strap free then it’s a good option especially if you have a compatible smartphone.