With a plastic mask cinched over my mouth and nose and sweat running down my cheeks, I sprinted on a treadmill.

Next to me, Seattle Performance Medicine exercise physiologist Brady Feutz monitored both my running and a screen collecting data from the breathing mask and a heart rate monitor strapped to my chest.

Every couple of minutes, Feutz reached over to increase the treadmill speed. He then asked me to point to a chart indicating how hard the effort seemed. As the pace climbed, and my breathing grew more labored, he encouraged me to keep on going.

“Run as long as you can,” Feutz said. “When you can’t go any further, give me a thumbs-down.”

I found myself running to exhaustion at Seattle Performance Medicine last week because I wanted to experience their exercise testing firsthand. As an endurance athlete, I’d heard friends talk about finding out their own VO2 max, anaerobic threshold, and aerobic threshold – all indicators of how well the body is handling exercise. By collecting this data, I could find out whether my muscles were working efficiently, and what changes in diet or workouts I may need to make.

I also wanted to explore the topic because I knew newbie athletes, recreational sports participants and even couch potatoes can benefit from this kind of testing. You don’t need to be a marathon runner to learn something from the tests. Even someone starting out can collect the information and develop a healthy lifestyle plan.

“We see everyone from elite athletes to people who have never exercised before,” Feutz said.

When it came to choose a facility, all of my athletic friends recommended Seattle Performance Medicine. The clinic houses a $250,000 advanced lab of physiology equipment. Patients pay $350 to undergo a series of exercise tests and receive a subsequent consultation.

Unlike many testing spots, Seattle Performance Medicine has a physician, Dr. Emily Cooper, conducting the post-exam analysis. I felt I’d be getting the best advice by working directly with a credited doctor who has been practicing for 25 years.

“I know we’re the best in town,” Cooper said. “We combine medical physiology with performance testing. At most places, physicians don’t look at the data, and they don’t meet with patients.”

Dr. Cooper regularly advises endurance athletes like myself, but also patients with eating disorders, high cholesterol, obesity, high blood pressure, metabolic disorders, fatigue, thyroid problems, chronic injuries, or little history of exercise. Her range impressed me.

Seattle Performance Medicine also caters to multiple athletic disciplines. Patients can choose to be tested on the exercise machine they are most comfortable with. I opted for the treadmill, but there’s also a stationary bike, rowing machine, and elliptical machine. Swimmers can go off-site to a pool and strap on a scuba mask that transmits data to a portable device. The tests tell athletes where their training may be off-balance, or where they may be spending too much time.

In the end, what I found in my results both intrigued and surprised me. I’ve been an athlete my entire life, and figured my data would be somewhat in the normal, active range.

Instead, Dr. Cooper told me that I was a true outlier with some serious issues that needed to be addressed.

“Things are wrong,” Cooper said.

Several hours before she began to explain my shortcomings, the afternoon kicked off with simple measurements of blood pressure, height and weight. Then, I spent 15 minutes lying on a table, mask strapped over my nose and mouth. The mask measured the oxygen I breathed in and the carbon dioxide I exhaled, indicating my resting metabolism.

The next two tests took me to the treadmill. For the first, Feutz increased the incline every couple of minutes, until I could no longer run any steeper of a hill. The measurements he took from the mask and heart rate monitor charted my VO2 max, or the maximum amount of oxygen that can be used by working muscles to convert fuel to energy. Typically, elite athletes have a very high VO2 max. The number, however, is only partly determined by training, as it is also genetic. It took me about 20 minutes to reach breaking point.

After a short breather, I hopped back on the treadmill for the speed test. This one, using the same instruments, measured first my aerobic threshold, where the anaerobic system kicks in to provide the body with the energy required for higher intensity exercise.  

Once I began sprinting, the test measured my anaerobic threshold. At this point, muscles begin to release lactic acid, making someone feel fatigued. The second run also lasted about 20 minutes.

After the test, I hopped in the Seattle Performance Medicine shower and then caught up on e-mail while waiting for Feutz and Cooper to process the results. It took them a full hour – in part, they told me, because my numbers were not typical.

My VO2 max, Dr. Cooper said, was 64 milliliters of oxygen per kilogram of body weight per minute, which falls into the competitive endurance athlete category. The test confirmed that my muscles should be capable of drawing a lot of oxygen at high intensities.

The other results, however, weren’t all so rosy. As Dr. Cooper put it, “A lot of things are off.”

My heart rate, both resting and when running, was about 10 beats per minute lower than expected. At 169 beats per minute, my maximum heart rate was a full 20 beats below what would be expected of someone my age. And when I stopped running, my heart rate immediately plummeted by 61 beats – too fast, too far.

“Your heart rate is inappropriately low,” Cooper said.

The tests also showed that my muscles were utilizing fat and protein for fuel, and relying far less on carbohydrates than they should. Since fueling with fat requires more oxygen than fueling with carbs, my body wasn’t exercising efficiently.

“It’s a red flag when we see excessive fat burning,” Cooper said.

So what’s going on? Dr. Cooper told me that the most likely culprits of my inbalances are poor nutrition, with not enough carboyhydrate consumption, or a hypothyroid condition. Since I eat carbs many times daily (big fan of rice, pasta, cereal, bread, fruit and all of that goodness), we both thought the thyroid was a more likely contender. The autoimmune condition, which can be corrected with supplements, can cause all of the results outlined above.

For now, I must wait to see results of the detailed follow-up blood work. I came to Seattle Performance Medicine as an intrigued journalist and athlete, not expecting to hear any major recommendations for changing my own health. The surprising results, and the knowledge that will follow, may be an unexpected huge side benefit.

If Dr. Cooper is correct, figuring out the cause of my outlier tendencies should give me more energy and efficiency in life in general. And, as an added perk, it could also make me a faster rower and runner.

Dr. Cooper, for her part, is equally interested in looking at the blood work results.

“I love cracking a code,” Cooper said. “It’s a challenge each time, piecing together the information and coming up with improvements. That’s my passion.”

If you’re interested in performance testing, appointments can be made by calling Seattle Performance Medicine at 206-632-4575. Testing is also available at Herriott Sports Performance and a handful of other Puget Sound area facilities.