Body by the Numbers

As I put on the tight, elastic swim trunks in the changing room in Baseline Fitness, I realize I have never worn Speedos before. I am not a fan. It’s not so much the look – admittedly not great – but the damn things bite into my inner thighs more than clothing should.

I leave the changing room and walk directly into the testing room, where an egg-shaped spaceship sits in the corner. This is the Bod Pod, a machine built to precisely test body composition. I sit on the short plastic seat inside, and Eve Ann Metzger tells me to breathe normally. She closes the door, and the machine begins to whir as it forces air into the small pressurized cabin. The test lasts 40 seconds and is repeated three times. Then I climb out to learn the results.

I’m fully clothed again and sitting at the front desk while Metzger, Baseline’s owner, explains the Bod Pod test analysis. There are other methods of determining someone’s body composition, like skin-fold calipers and bio-electrical weighing, but she says that the Bod Pod provides the best combination of accuracy and convenience. The machine works by filling the sealed cabin with air and then measuring how much you displace – “like taking a tape measure to your entire body,” she says.

Once they have a body-density measurement, trainers factor in sex, age and height to calculate a person’s lean mass and body-fat percentage. On a simple level, this information can show if someone is at risk for health problems based on body-fat percentage, which is rated on a scale that runs from above 30 percent (too high) to below 5 percent (too low).

“We do see so many people that are really surprised at where they are,” says Metzger. “They look at the categories, and they’re really surprised to find that, you know, ‘Wow, everybody tells me I look normal and okay, and I’m in an excess body-fat category.’”

For most people – whether they are new to exercise or professional athletes – the Bod Pod results provide a snapshot of their current fitness level so that trainers can create realistic body-composition goals and then gauge progress through regular testing. Metzger advises people looking for physical changes to get tested about every four to six weeks.

And it’s not just about exercise – the dietary part of the equation plays a huge role.

“Your nutrition’s going to have the most impact on body-fat percentage. I hate to say that – I own a gym,” Metzger says while laughing, adding that diet also factors into the ability to build lean mass. The more lean mass you have the more efficient your body becomes, as more muscle increases your resting metabolism, thereby increasing the number of calories you burn throughout the day.

The Bod Pod operates in conjunction with the exercise facility at Baseline to push people toward better health and fitter bodies. The scientific numbers provide the goal and the starting point, and then the instructors supply a progressive training program. They increase the intensity, frequency or duration of workouts as incremental goals are met so that people don’t plateau before achieving long-term goals.

It all comes down to documenting what you’re doing, according to Metzger. “Obviously, we’re numbers people here,” she says. The stats from the Bod Pod don’t lie, and if people record their diets and how they’ve been exercising, then they will know the basis of their body composition, good or bad. It can be a road map to improvement, or it can point to where they went off course.

For more information about Baseline’s Bod Pod testing, other fitness assessment tools or personal training, visit