Like many of us who run, bike, and swim, I'm always seeking to improve my performance. As a triathlete, I have set personal records at each race. As I began training for my third triathlon, I wanted to keep up that streak. My aim was to shave a few minutes off the half-mile swim, 15-mile bike ride, and 3-mile run -- technically, a "sprint triathlon." But instead of hiring a trainer to put me through my paces, I relied on the latest entrants in the exercise market: wrist-worn fitness computers.
First designed as sports watches, these high-tech gadgets from Garmin (GRMN ), Timex, Nike (NKE ), and Polar have become all the rage, especially among growing numbers of triathletes. The devices, which sell for $300 to $370, tell me how many beats per minute (BPM) my heart pumps (via a chest strap) and the number of calories I'm burning. They measure how fast and how far I run, bike, and, in some cases, swim. And, to make tracking my performance easy, preset alarms guide me through my warm up, speed workout, and cool-down period.
The mini fitness computers prove invaluable after the workout -- when I monitor my progress. I can download data on to my PC for an intensive analysis, complete with color-coded graphs and bar charts. For example, on a recent 3.5-mile run, I averaged 8.45 minutes per mile, traveled 7.1 miles per hour, burned 332 calories, and had an average heart rate of 143 BPM. After 14.4 minutes into the run at the 1.7 mile mark, I hit my peak performance at 156 BPM, or 84% of my maximum heart rate. Such data helped me set goals for my next run -- and the work paid off on July 31, when I trimmed 7 minutes and 32 seconds off my triathlon time.
The Garmin Forerunner 301 and the Timex Bodylink 5E671 rely on the Global Positioning System (GPS), which can track running and biking routes anywhere in the world. The Garmin can navigate me back to my starting point, warning when I retrace my steps incorrectly. One drawback: Heavy tree foliage can obscure satellite signals, compromising accuracy. Another is that neither system clocks distance and speed indoors.
Unlike the satellite-based systems, the Nike Triax Elite HRM/SDM and the Polar S625X use a watch and a small sensor attached to your shoe. They track the exact distances the foot travels. The data for biking and swimming are limited to time and heart rate, since the devices are designed mostly for running. Polar sells a separate speed and distance sensor ($39.95) that can be mounted on a bike.
Of the four watches, the Garmin and the Polar are my favorites -- though your needs should dictate your choice. People who tend to exercise indoors might prefer the Polar, for instance, because the technology does not require beaming up to a satellite.
The Garmin's set-up directions are a breeze. After putting the heart rate monitor on my chest, I simply strap the Forerunner on my wrist, turn it on, and all the data I want to see (time, speed, distance, heart rate) clearly appear in the 1 1/2-inch by 1-inch window. In contrast, the Timex system includes not only the watch and chest strap, but also an arm device for the GPS signals and a waistband-mounted data recorder. With it, I feel like the Terminator, and I don't welcome the extra 10 ounces.
When I switch between swimming, biking, and running, the Garmin screen prompts me on which of six well-marked buttons to push. On bike rides along heavily shaded paths, the device may flash a brief warning that the GPS signal is weak. When I swim, the water blocks the GPS signals, though the time and heart data still come through. For diehards, Garmin sells a mounting kit ($24.99) that lets you attach the unit to a goggles strap to receive GPS signals. The Polar also lets you see only the time and heart rate while under water.
The Garmin comes with a charger, which can be plugged into a standard wall outlet. Fully charged, the unit provides 14 hours of workout time. To download my exercise data, I simply plug the device into a computer via a USB port. Other devices require you to buy additional equipment. For Polar, you'll need an infrared wand which runs from $19 to $30. With the Timex, the data recorder costs an extra $75.
The big selling point for the Garmin is its built-in workout buddy, or virtual partner. I can program a little stick person (on a bike, if I'd like) to move at a certain speed and distance, and the device informs me how far ahead or behind I am from my buddy. On one bike ride, my virtual partner surged a quarter-mile ahead. I sped up, ultimately beating the little fellow and improving my overall biking time -- and I didn't have to worry that my training partner would be annoyed by my competitive streak.
By Toddi Gutner