Raising the Bar on Optimal Fitness

9 March 2010

Whether you're a Paralympic athlete, a weekday warrior or a Sunday jogger, identifying your optimal workout window could certainly improve your quality of life. But if you're recovering from a period of inactivity due to injury or have a chronic respiratory illness, identifying optimal exercise protocols and avoiding muscle injury could be life changing — not  just life enhancing.

Through cutting edge science and funding from MSFHR, Dr. Darlene Reid, Professor, Department of Physical Therapy, UBC and Director, Muscle Biophysics Laboratory at the Vancouver Coastal Health Research Institute, is working on the development of two tools that could revolutionize the way we think about and perform exercise.

"Most of us have a therapeutic training window, and as we get older that window becomes smaller," Dr. Reid says. "In people with chronic respiratory disease, who I work with, that window is very small to begin with. You want them to exercise hard to enough to improve their fitness level but not cause damage. So we're looking at how to perform exercise safely."

A key factor in the safety equation is adequate oxygenation. "We believe there's a critical level of loss of oxygenation in the muscle that affects fitness, and when oxygenation goes below that level the risk for muscle injury exists," says Dr. Reid.

To identify those levels, Dr. Reid and her research team are using near infrared spectroscopy to measure tissue oxygenation in a variety of different settings, including the operating room. "We have used it to monitor tissue oxygenation of limb muscles during orthopaedic surgery," she says. "We're also using the device to monitor oxygenation of the muscles we use to breathe, and we will take the device into the intensive care unit to look at people when they're breathing under load and being weaned from a mechanical ventilator."

Importantly, near infrared spectroscopy can be used to identify when the muscle is deoxygenating under load during particular types of exercise. "So if a particular muscle is deoxygenating during a particular manoeuvre, we might coach the person to do that exercise in a different way," Dr. Reid says.

Additionally, Dr. Reid, in collaboration with researchers at the University of Guelph, is working on a blood test capable of detecting muscle injury.

"When muscle becomes injured it can become more porous or permeable, and some of the proteins normally found in muscle can be released into the blood stream," she explains. "We are looking at one particular type of protein called troponin I. The troponin I test may be very helpful once it's perfected because it could tell us when different muscles are being injured."

By figuring out the ideal therapeutic windows for people who may have been immobilized for a period of time due to injury, or who suffer from chronic illness, it will be possible not only to progress their physical fitness, but to optimize it, and in so doing enable a greater level of fitness for competitive and casual athletes as well.