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Under Armour Armour39 Review: Beast Mode Unlocked

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I know what you're thinking and no, this is not another sportswear company entering the wearable tech arena to cash in on all of you suckers. This is different, and that's a good thing.

First revealed back in 2011 at the NFL Combine, the then called E39 was embedded in a shirt that tracked an athlete's heart rate and g force during acceleration, among other things. Fast forward to earlier this year and the consumer debut of the Armour39. It's not an activity tracker, like a FuelBand or Fitbit, but an electronic performance aide that tells you how hard you're working when you're working it out.



Heart rate monitors like the Armour39 (A39) aren't new per se. Polar and Garmin have been making chest-worn monitors for quite a while. Even Motorola makes one for its MotoActiv line. And the A39 is really no different except for the usual (and somewhat obnoxious) in-your-face Under Armour graphics and branding.


That aside, the A39 chest strap is relatively comfortable to wear and rarely slips down the torso once you've figured out the right size. The front of the strap can be a bit stiff at first but it softens after a couple wears.

The module that collects your biometric data is a half-dollar sized, replaceable battery-powered, Bluetooth disc that you insert into the strap before a workout. It even does an Iron Man impression and flashes when you've successfully connected the iOS app before your workout starts, like so.


Under Armour says the module's battery will last dozens upon dozens of hours. And because it's powered by a CR2032 battery, swapping it out is a piece of cake. Just be sure to pop it out of the strap when you're done, so it doesn't drain the battery more than is necessary. And hang dry the strap.

Using It

To start, you'll need to pair the A39 with your iOS device and the app to undergo a 10-minute, five-part assessment, which collects your resting heart rate, max heart rate and other things in between. This baseline data helps UA analyze each workout and whether or not you're hitting your WILLpower goal, which, by the way, is an option you can flick on or off. Like any other chest strap, it needs to be wetted down before it's strapped on.


Your WILLpower score or goal is set by you and measures your level of exertion based on how hard your heart is working. You might sweat a lot when you work out but that doesn't accurately measure whether or not you're working hard enough. If your ticker isn't in the zone—based on your age/gender/etc.—then what's the point of exercising? During your workout, you'll see the below stats in real time. You'll know when you're in the zone when everything that's green—your heart rate—turns to red indicating that you're in an optimal heart rate zone.


When you're done, you'll see this.


Because of the nature of heart rate monitors like this, the A39 wasn't exactly the easiest thing to compare against similar devices. You can't really wear two chest straps at once. I tried. It did not go well. In any event, I used Polar's FT60 as a parallel and found that the data captured was more or less the same. There weren't any noticeable spikes or dips during my usual two mile run and the data captured by both were more or less the same. But it's a lot easier to look at your phone than your wrist and that tiny little display with all the bells whistles that the FT60 comes with.


As a performance monitor, the A39 is about as motivating as a personal trainer screaming in your face to get your knees up and not to break form. There's nothing better than seeing your level of intensity and heart rate in real time. There's simply no room for bullshit. You either worked out or dicked off.


You don't always have to have your iOS device on you while working out either. The module will collect up to 16 hours of data before it needs to be offloaded, says Under Armour.


As much as I thought WILLpower was going to be a thing. It was a secondary feature to seeing actual biometric feedback. I didn't work out any harder because I wanted to reach my WILLpower score. I wanted to work out harder because I could see that my heart rate wasn't in the zone.


Audible cues would have been a nice 1.0 addition, like in Nike's Running app. Constantly looking at your phone isn't always conducive for certain types of exercise.

No Android app? No Android app.

Should You Buy It?

This is not, I repeat, this is not an activity tracker like the FuelBand, UP or Fitbits of the world. This isn't meant to be worn all day. If you're looking to better measure and tweak your workout sessions, then this is the monitor to get.The A39 as is will set you back $150. But if you don't have an iOS device, then you'll have to shell out an extra $200 for the accompanying watch, which doesn't appear to be live on the company's site just yet. Compare that to Garmin or Polar (depending on the model) and $350 for both isn't all that crazy sounding.


With summer just around the bend, it's time to get that winter body in order and with the A39, you'll get there in no time. [Under Armour]