Digital trainers

Garmin Forerunner 310XT
An extreme watch for extreme athletes, the multisport Forerunner 310XT is as comfortable on land as it is under water. Runners and cyclists can use the 310XT to track their distance and pace on the road, and swimmers can take advantage of the watch’s waterproof shell to time their laps in the pool. Optional heart-rate monitors and foot pods provide more precise data; otherwise the watch’s built-in software lets you wirelessly sync your workouts to your Mac or PC. Best of all, the 310XT’s 20-hour battery ensures it’ll keep ticking long after your personal power meter has drained. Don’t need all the bells and whistles? A streamlined version of this watch, the Forerunner 110, will be available just in time for the Boston Marathon in April. $350 (310XT), $199 (Forerunner 110) at garmin.com.

Timex Ironman Race Trainer
Whether you’re a seasoned marathoner with several races under your belt or a weekend jogger sweating out the previous night’s liquid dinner, the Ironman Race Trainer is designed to give you a leg up on your training. The all-in-one unit includes a chest strap that wirelessly beams your heart rate to the watch, helping you track your cardiovascular strength. The Race Trainer also stores up to ten workouts, and like a diligent coach, it’ll record every aspect of your workout, from calories burned to the amount of time spent within your selected target heart-rate zone. An optional USB thumb drive lets you log your workouts onto your computer. $150 at timex.com.

Casio G-Shock G-Rescue G7900
If your idea of a workout involves trudging to a campsite, the G7900 is the watch for you. Designed to resist repeated exposure to the elements, this shock-resistant watch is built like a tank. It’s water resistant up to 200 meters (656 feet) and automatically displays local time thanks to its multiband radio. A built-in solar panel allows the watch’s rechargeable battery to feed off the sun, and the G7900’s five alarms and two stopwatches ensure you’ll never miss a beat. $150 at gshock.com.

Nike+ SportBand
Don’t want to carry a computer on your wrist? The Nike+ SportBand trades versatility for simplicity, letting even the biggest Luddites digitize their workouts. This no-fuss watch wirelessly communicates with the included Nike+ sensor, which you strap onto your sneaker. The watch then displays your distance, pace, time and calories burned. The SportBand also connects to your computer’s USB port, letting you upload your workouts to nikeplus.com. $59 at nikerunning.com.

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