Now at a gym near you: high-tech testing

Once reserved for elite athletes, precision fitness analysis goes mainstream.

By Jeannine Stein
Times Staff Writer

February 12, 2007

Giusy Mele-Brown is no slouch when it comes to exercise — she clocks in about two hours of workouts most days. But in the last six years she had seen her weight steadily climb. She eventually gained 25 pounds.

What got the 40-year-old Pasadena real estate agent back on track, she says, was a fitness test previously available only to elite and professional athletes: a noninvasive analysis that determines when she's in her aerobic, fat-burning heart rate zone and when she's in her anaerobic, carb-burning zone.

The result? Mele-Brown lost 22 pounds in two months, even as she kicked her workouts down several notches, doing cardio at about 140 beats a minute instead of her usual 180.

Increasingly, high-tech fitness tests are popping up at gyms. There's the test Mele-Brown took, which determined the heart rate at which she reached her anaerobic threshold, the point when the body stops using fat and oxygen for fuel and relies, instead, on carbohydrates. This helped her pinpoint her anaerobic zone, where the body produces lactic acid, breathing becomes difficult, the heart races and muscles quickly tire. Working out in this zone will improve the cardiovascular system but won't burn the body fat most people want to shed.

Another test now available determines resting metabolic rate — how many calories are burned per day at rest — so that people can accurately figure how many calories should be consumed and how many need to be burned.

Not long ago, these tests, which require sophisticated equipment costing thousands of dollars, were available only at human performance labs, elite sports-training facilities and some hospitals. Today, they're increasingly being offered at private training facilities, larger gym chains and even some corporate fitness facilities, the result of a demand from trainers plus savvy marketing by equipment manufacturers. The facilities generally offer the tests at a price tag that ranges from about $100 for the test alone to several hundred dollars for bells and whistles, such as individualized exercise prescriptions, with or without a trainer.

Health clubs tout the benefits of knowing these exact numbers. They say it's helpful for people struggling with losing weight or trying to improve their performance, whether on a treadmill or in a triathlon. But some exercise experts aren't sure that any of this is necessary. They point out that many other fitness tests that have been around for decades (such as using a numeric formula to estimate maximum heart rate) have served the workout population just fine, even if they're less precise.

"You don't need an anaerobic threshold test in order to exercise safely and effectively, regardless of what your goals are, says Mitchell Whaley, a professor of exercise science who also works with the Human Performance Lab at Ball State University in Indiana. The old, low-tech methods are close enough, he says. If someone wasn't working out in their optimal fat-burning zone, for instance, exercising for just a few more minutes would make up any deficit.

Those who offer the tests claim a host of benefits.

Matt Berenc, fitness manager of Equinox in Century City, says the tests can mean the difference between great results and good results. (The upscale chain offers testing at the Santa Monica and Westwood gyms, and plans to do so at its recently opened Century City location.) With testing, he says, people can avoid exercise plateaus by always knowing when they're in a fat-burning zone.

In the case of Spinning enthusiasts, he adds, the problem may be overexertion. Yes, people are getting in shape, but classes are usually ramped up to a very high intensity, putting many participants in the less ideal anaerobic zone for much of the time.

Such tests might prevent beginner's burnout or injuries from overexertion, says Robert Forster, founder of Phase IV Scientific Health and Performance Center in Santa Monica, a sports training facility that offers testing not only to the athletes it serves but also, now, to other health-minded folks. And accurately figuring one's resting metabolic rate helps people know how many calories they're burning at rest as opposed to how many they think they are, says Todd Durkin, trainer and owner of Fitness Quest 10, a personal training and workout facility in San Diego. "One thing I think we trainers don't do enough of is objective testing to give feedback to clients," he says.

Of course, good trainers have been refining and tweaking their clients' programs for years, sans expensive testing. But while many trainers excel at guiding their clients through weight training, cardio often gets short shrift, says Kymberli Allen, a master trainer with Sports Club/LA's Target Zone program. "Trainers will focus on muscles, then tell their client to get on the bike for 20 minutes and not give details to them," she says.

William J. Kraemer, kinesiology professor at the University of Connecticut, sees some validity in testing. "I go to the gym and see people working out, and I'm not sure many of them know what they're doing," he says. "They have no goals, and no evaluation process."

But Kraemer, who's also affiliated with the school's Human Performance Laboratory, argues that those considering shelling out big bucks should first determine why they're doing it: "Why do you need to measure it? Are you going to be training to improve it?"

Many fitness experts believe that older, proven methods often work well enough.

Take heart rate zones. The formula most people use is 220-minus-age to get their maximal heart rate, the highest heart rate attained during exercise. Then they calculate 60% and 90% of that number to get the optimum range for cardio exercise.

The math-challenged can go even simpler, by paying attention to their rate of perceived exertion, which is little more than noting one's breathing and heart rate while working out. If your breathing is slow and heart rate barely raised, you're probably not exercising hard enough. If you're out of breath, your heart is beating very rapidly and your muscles feel maxed out, you're likely in an anaerobic zone.

Basal metabolic rate, or calories burned at rest per day, can be estimated using gender, age, height and weight: A 40-year-old, 130-pound, 5-foot-4 woman, for example, burns about 1,325 calories at rest. (To calculate your basal metabolic rate, go to health.discovery.com/tools/calculators/basal/basal.html.)

In fact, Whaley says, exercisers who can't feel their pants getting looser shouldn't necessarily blame their workouts. "What we've found over the years is that most often, when people are not getting results, they're really eating more than they're reporting," he says. "When they start working with a registered dietitian, that usually takes care of the mystery."

If people do opt for testing, he adds, they should find a qualified person to administer the test and accurately interpret the results.

The two most popular types of testing being offered now are resting metabolic rate, which measures oxygen consumption at rest while breathing into a mask, and VO2 sub-maximal testing, which calculates anaerobic threshold.

VO2 max refers to the maximum amount of oxygen, in milliliters, that the body uses in one minute, per kilogram of body weight. Because reaching maximal levels is too challenging for most people (and requires a doctor to be on hand), VO2 sub-max tests are usually done instead. The subject exercises on a cardio machine while wearing a mask. Anaerobic threshold is calculated by measuring how much oxygen is being used during exercise; at anaerobic levels, the body stops using oxygen for energy. A corresponding heart rate for that threshold is noted.

Anaerobic threshold can also be measured using a method known as lactate threshold testing: This determines how much lactic acid is in the blood. Because this test requires a blood sample, it is usually only offered at elite sports facilities, universities and hospitals.

Armed with fitness test results, exercisers know how fast to pedal their elliptical trainers and how hard to pump their bicycles to stay in specific zones. It also takes the guesswork out of high-intensity interval training, which requires switching often from aerobic to anaerobic levels.

Some caveats: All of these numbers can vary as someone ages, gains or loses weight and becomes more or less fit. Retesting several months or a year later is usually suggested to see what, if any, changes have occurred.

And, of course, anaerobic threshold numbers don't always translate from one piece of equipment to another; threshold might be reached at a different level on the treadmill than the elliptical trainer, perhaps requiring testing on more than one piece of equipment.

Cyclist Peter Abraham was at Phase IV recently for a lactate threshold test. He has been competing seriously in cycling races for the last year and a half but finds that juggling races, plus a full-time job and a family, leaves him little time for training. Training more efficiently became a priority.

Although he had used a heart rate monitor before, "I wasn't clear on what I was doing with it," he says. Then, a year ago, he was tested for the first time and learned his anaerobic threshold heart rate.

His training, he says, has changed dramatically.

Now, instead of riding all-out during every training ride, he does some work at moderate levels to build up his endurance, and some at higher levels to tax his cardiovascular system, always using his anaerobic threshold heart rate as a guide.

Since tweaking his routine, Abraham says he not only feels more fit but also is pleased with his amateur cycling race results in the last year. "I got some top five spots," he says, "a breakthrough for a 43-year-old guy who's racing against younger guys."