SAN JOSE, Calif. - Flying down the road, cyclist and triathlon coach Eric Bean flattens over his bike frame. He glances at his left wrist, gauging how hard he should pedal and how long he can last.
Other athletes, breathing hard and pouring sweat, might listen to their pounding pulse and screaming muscles instead. But Bean relies on a personal, portable heart rate monitor, trusting the two-piece digital system to keep him rolling strongly and safely.
The watchlike display on his wrist tells him how fast his heart is beating, picking up a radio signal coming from a sensor on his chest. Bean checks once. A couple of minutes later, he looks again.
By keeping his heart rate at the correct level, Bean says he can hit an athlete's training dream - cranking through the right amount of effort needed to improve performance, without overdoing it.
In relying on heart rate monitors, Bean takes advantage of a technological wave reshaping athletics and physical fitness. Personal fitness devices are letting people serve as their own coaches and work out on their own terms.
"It's a much more fun way to train," said Bean, 28, who coaches Stanford University's Triathlon Team and runs an athletic training company. "It's more motivating. It's as if before you were blind, and then you can see."
Heart sensors and step gauges keep everyone from professional athletes to reformed couch potatoes on track. Motion-sensing video games get kids on their feet. Bathroom scales that measure both weight and body composition show how much body fat you carry, if you can stand to know.
In the process, digital gadgetry - usually a diversion from physical activity - is literally keeping people of all ages moving.
"Making active play more popular is a very positive thing," said Dr. Tom Robinson, director of the Center for Healthy Weight at Lucile Packard Children's Hospital at Stanford. "It's important that these industries realize they can be profitable being part of the solution, not just part of the problem."
Fitness games and gadgets do have limits. The hefty size of the American waistline makes it plain that many people ignore the devices. Some users have dumped them.
The success of fitness technologies lies largely in their ability to motivate someone to exercise often and well, fitness experts say.
Heart rate monitors, which cost anywhere from about $50 to $350, have been widely adopted by endurance athletes because they deliver a precision workout. Athletes such as Bean combine the monitors with measurements of lactate, an exercise by-product found in the blood, to determine optimal heart rates and workout levels.
But how do such benefits translate to most people, for whom the word "triathlon" is defined as "Something I will never, ever do"?
The answer, many health leaders say, is to tie exercise technologies to everyday life.
Pedometers, which gauge how many steps a person takes, are one such measure of routine activity. The devices have been widely promoted to get Americans moving, even if that movement is just lots of walking.
Often worn at the waist, the simplest pedometers measure only steps and distance, recording steps by sensing body motion. Such streamlined versions cost as little as $10. More elaborate models, which can sell for as much as $40, include calorie consumption estimators, clocks and pulse rate readers.
Federal health leaders recommend adults get at least 30 minutes of moderate physical activity five times a week, and say walking is an easy way to hit that goal. Many walking programs set step goals, such as 10,000 steps a day, that are most easily counted with a pedometer.
"A pedometer really does serve as a powerful motivator to get people to take more steps," said Dr. Cedric Bryant, chief exercise physiologist for the American Council on Exercise. "You don't have to do the tracking, but you can check and get a good sense of how you are doing."
Some users, however, find the small devices easy to break or lose.
Tricia Loog, who tried using one in her own fitness efforts, gave up after having three or four pedometers slip off repeatedly. She still walks and goes to the gym regularly, but has ditched the step counter.
"It would fall off and break. I find them now when I go to the dressing room in the department store - other people are losing them all over the place," said Loog, who works for the city of San Jose and puts herself in the "over 55" category. "It might work for some people, but it didn't work for me."
Some technology makers are cutting back on the pieces users must move or touch.
The EyeToy, a relatively new type of video game developed by Sony gets rid of button-pushing almost entirely. Instead, gamers play by moving their bodies.
The technology relies on a small camera attached to Sony's PlayStation console. The camera recognizes body motion and feeds it back into the game. To play, you wave your hands, kick your feet, or just move yourself to "push" buttons on the screen or interact with the game.
The EyeToy's second game, EyeToy: Groove, gets players dancing, building on a trend started in arcades by games such as Konami's "Dance Dance Revolution." EyeToy: Groove, produced by Foster City-based Sony Computer Entertainment America, includes a calorie consumption estimator for those who want to blend fitness into their jams.
"One of the reasons for developing this is to help get kids off the couch and promote a more active lifestyle," said Sony spokesman Tim Cummins. "A calorie counter was a natural fit for the game."
Robinson, the Stanford children's weight and fitness expert, said it is still best for kids to get away from the TV. For one thing, a game of soccer is a lot cheaper - Sony's PlayStation console sells for about $150, and the EyeToy camera and EyeToy: Groove together go for another $50.
But Robinson said he also knows how many children are hooked on video games, and says active choices beat glassy-eyed button punching any day.
"It wouldn't be my first fitness choice to a parent," he said. "But if they already have one of those things and their kids are spending a lot of time on it, a game like this is worth checking out."
And some would-be athletes may prefer no-tech options entirely. Many people hike, run or cycle to unplug from digital life. They can still get a good workout without gadgets, fitness expert stress.
"Some people just don't like the gadgetry," said San Jose-based fitness trainer Anna Kuramoto. "I've had clients where pushing a button is too much for them."
But for others, like Bean, fitness technology has melded into a seamless part of their sports success.
"It's not a hassle," said Bean, who is applying to medical school and wants to use his fitness knowledge to promote better health. "It actually becomes fun to see your progress. I just really like seeing what is going on."
Online information on fitness and workout technologies:
-For the heart rate monitoring basics from the American Council on Exercise, go to www.acefitness.org/fitfacts/fitfactsdisplay.cfm?itemidequals38
-For walking and pedometer information from the federal Centers for Disease Control and Prevention, go to www.cdc.gov/nccdphp/dnpa/physical/healthprofessionals/promotingwalking.htm
-To see an example of the type of triathlon training workouts that include frequent heart rate monitoring, go to Eric Bean's Web site at http://www.beanathlete.com/coaching/coachingserv.phpind
(c) 2004, San Jose Mercury News (San Jose, Calif.). Distributed by Knight Ridder/Tribune News Service.