The Armour 39 fitness tracker is for exercise enthusiasts

Hi. This is Roger Cheng for CNET.com, and today, we're taking a first look at Armour 39. No, Armour 39 isn't the last weapon in some Alien Shooter. It's actually a fitness tracker from athlete apparel maker, Under Armour. It's Under Armour's first foray into the red hot fitness gadget market. So, it inevitably invites comparisons to Nike's FuelBand. But Armour 39 is a different product. I expect it's going after a different kind of gym rat. One that's a bit more hardcore. For one, Armour 39 is a strap that goes around your chest or slightly below. I'm sorry, ladies. I won't be modeling this one for you today. On one side of the strap are the sensors to monitor your heart rate. On the other side is what Under Armour called its bug, which acts as the brain of the tracker. The bug takes all the data, uses Bluetooth to transmit information to your phone. The bug could be removed so you can wash the rest of the strap which, trust me, gets dirty pretty quickly. Armour 39 measures a few key metrics: heart rate, intensity, calories burned and time. But what sets Armour 39 apart from other fitness trackers is that it takes the data and calculates each workout into a WILLpower score that ranges between 1 and 10. Yes. WILLpower is one of those made-up metrics like Nike FuelBand's. But unlike Nike, which has a score that constantly accumulates, WILLpower acts more like an assessment of each workout session. I worked out with Armour 39 half a dozen times. And I realize, I'm not particularly intense or have a whole lot of willpower. In fact, things got gradually worse after two weeks or so went on. For better worse, I'm not as hardcore about working out, and the stats definitely showed. The readings, as you can imagine, are more accurate than the Fitbit or FuelBand, which is an accelerometer to track your progress. To capture your heart rate, you get a better read of how well or how poorly you're performing. I like the app interface, which is clean and simple. But it was a little limited to what it could do. I was hoping for a website version with more detailed stats, as well as the ability to share with your friends. Armour 39 only works with iOS devices right now. Under Armour also introduced a watch that can sync with this heart monitor, giving the need for an iOS device. But it's not yet available for consumers. Overall, Armour 39 takes accurate measurements and is a decent-- although somewhat limited way of measuring the progress of your workouts. But I'm not sure I wanna carry around a strap to the gym. It's just another thing I have to remember-- Armour 39 is definitely for the intense gym rat. For CNET.com, I'm Roger Cheng, and this has been the first look at Armour 39.