Pocket-Size Personal Trainers

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Here's my idea for a dream exercise machine: I input my weight, the number of calories I want to burn and how much time I have. Then I power up the gleaming, multigeared thing--and it goes to work by itself while I return to my favorite chair, play online poker and eat maple-glazed doughnuts.

Sadly, that Utopian scenario will arrive around the same time as the flying car. Meanwhile, my waistline is expanding in proportion to the national debt. A recent checkup confirmed my worst suspicions: I'm borderline everything, from diabetes to elephantiasis. Luckily, there's a raft of new gadgets on the market that use high-tech sensors to help me get a handle on my love handles. During the past month, I've focused on two gizmos that promise to pound the Quittner bod back into its more kittenish shape. One, the cigarette-lighter-size (and awkwardly named) Smheart Link, works with an iPhone to monitor my heartbeat during customized daily workouts. The other, the Bodybugg, measures my caloric expenditure. I recommend each. (Watch Josh Quittner get fit with his web and tech gadgets.)

The Smheart Link ($155 at Amazon.com wirelessly tethers an iPhone to a heart-rate-monitor belt. (I got a $42 garden-variety Garmin belt.) Smheart Link uses several free apps to manage fitness routines pegged to your heart rate. I, of course, chose the crème de la crème app: iNew Leaf.

To get started, I went to BreakAway Performance in San Francisco, one of some 400 gyms in the U.S. that can perform a $250 "metabolic assessment." This test is part of the New Leaf's structured fitness system. Joel Ramirez, BreakAway's founder, put me on a stationary bike and placed an oxygen mask over my face. The mask was connected to a computer that measured my oxygen consumption and carbon dioxide output during a 20-min. stress test. With those data, plus my weight, height, age and gender, the computer created a report on my current health--including the ideal fat-burning and carbohydrate-burning heart-rate zones for me. Then the New Leaf system generated an eight-week daily fitness plan and uploaded it to New Leaf's website. (Additional assessments are $150 per eight weeks--still cheaper than a real, live personal trainer.) Once that's done, just fill in your New Leaf user name and password, and the iPhone grabs your daily workouts from the server. (See the top 10 iPhone applications.)

The beauty of the system is that it's portable; I can use it with any exercise machine. Mainly, though, I use it while on an exercise bike. Some days I'm assigned repetitions--2 min. in Zone 1, 2 min. in Zone 2, 1 min. in Zone 3, repeated 20 times--and on others, I do "recovery" workouts, say, 50 min. in Zone 2. The iPhone tracks my heart rate and tells me which zone I'm in and which zone is coming up. It's tricky, like walking a tightrope with my heart, but it's effective.

After each workout, I wirelessly upload the results to the New Leaf site and get a grade based on how well I stayed within the zones. (As usual, I'm a C student.) I'm amazed how efficient it is to burn calories when everything is based on your individual metabolism. One day I burned 1,000 "TruCalories" in 70 min. That's nearly two mai tais. My low-tech bike had estimated I burned only 550 calories.

But even these super-tailored workouts may not be enough. As it turns out, while the Smheart Link plays digital drill sergeant in my new life, the Bodybugg ($249 for the device, plus a recurring monthly fee) acts as the CIA, surreptitiously monitoring my caloric burn. The Bodybugg is a collection of sensors that measure such things as motion, body heat and sweat 32 times per second, then run the data through an algorithm. The company says the calorie estimate is better than 90% accurate. I also recommend getting the optional digital display wristband ($100), which syncs to the Bodybugg and gives you a read on calories burned so far, how many steps you've taken and other real-time data.

The hardest part for me has been estimating how many calories I consume at each meal. A database on Bodybugg's website of foods and their calorie counts helps, and I can manually add my own favorites. Then I periodically connect the Bodybugg to my laptop via a USB cable, and the device uploads to the site how many calories I burned. Pretty color graphs then compare intake with burn rate; the user interface is excellent here.

The idea is to figure out how much you usually consume vs. how much you typically burn. An online questionnaire helps you understand what you eat and sets daily goals. (To lose, say, a pound a week, the average human needs to consume 500 fewer calories per day than he burns.) Given my penchant for booze and fatty foods, my daily burn target was 3,150 calories--an output that requires me to take a daily two- to three-mile walk and do an hour on the bike. Or I can just eat less. Ha, ha, ha.

Still, it's been working for me. "Feedback is great," says Dr. Gerald Neuberg, a cardiologist in New York City and an old friend, whom I called for a second opinion. "It's engaging and motivating. If I had a calorie meter reading everything I put in my mouth, I would surely slow down my eating." In fact, that would perfect the system: a nose-mounted camera that measures caloric intake. Perhaps someday.

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