Triathlon training is serious business, so a do it all computer like the Garmin Forerunner 910XT is a training partner as important as a bike and a good pair of shoes. A plethora of features track all your data from the swim, the bike, and the run, so you can take your training to the next level in pursuit of your best results yet.Like a triathlon, let's start at the swim. Obviously, the Forerunner is waterproof up to 50m so it'll be right at home in the water. It's capable of counting strokes, tracking stroke style, measuring distance, and recording swim efficiency, whether you're swimming laps in a pool or cruising through open water. It can also track your path and display all this information in real time, so you can look at it on the go as well as after you've finished. After you blaze through T1 and hop on the bike, the Forerunner will be able to show you all the relevant ride data including speed, distance, gradient, altitude, and total ascent and descent. It will sync via ANT with a power meter or heart rate monitor, so you can also view cadence and power output as you ride. The features for the run are similar, with distance, speed, and pace measurements, as well as reminders to hit splits or grab some nutrition before you bonk. Maybe the coolest features are the Virtual Racer and Virtual Partner programs, which let you race against your personal bests, other users' times, or a pre set goal.With 20 hours of battery life, you'll probably run out of juice before the Forefunner does. It can display from one to four data points at a time, and switch between sport modes with the push of a button. All your data is saved internally and can be set up to sync wirelessly or via the included USB cable, so you can accumulate it all for closer analysis or upload it to Garmin's Connect program.