Exercise Physiology Lab

We perform Metabolic Testing including VO2 Max testing, Lactate-Ventilatory Threshold testing, Resting Metabolic Rate testing, as well as Body Composition/Body Fat testing. We work closely with our local triathlete community, as well as the general public to educate on the amazing abilities of the human body in exercise.

Metabolic Efficiency Testing
Metabolic Efficiency (ME) is an exercise science/performance concept that is based on the body’s ability to use fat or carbohydrate as a fuel source during exercise. The basis of ME deals with the production of carbon dioxide (CO2) and oxygen consumption (O2) as carbohydrates and fats are oxidized (broken down) during exercise. When the body breaks down carbohydrates and fat for fuel differing amounts of O2 are need and different amounts of CO2 are produced. The concept of ME provides a framework for placing the body at the right intensity of exercise to utilize fat as the primary source of calorie burn during long duration endurance exercise bouts.

The body (typically) has a large supply of fat stores and in the weight loss population our target of ME testing is finding the best intensity for exercise where storage fat is the primary fuel for exercise. In our endurance athlete performance population (runners, tri-athletes) the goal of ME testing is to find that speed, heart rate, or rating of intensity where fat-usage for fuel allows the “engine” to run for a longer time without fatigue. If the intensity of exercise is too high, the body switches to carbohydrate utilization primarily and fatigue is now “on the clock”. What this means for the endurance athlete is that you have a limited carbohydrate storage capability and once this is exhausted fatigue/exhaustion soon follows….and you will stop running or biking. If you can tap your fat storage (a much large energy pool) you can exercise/compete longer while preserving your carbohydrate stores.

Resting Energy Expenditure & Resting Metabolic Rate Testing
One of the more important clinical tests for our weight loss population is the Resting Energy Expenditure (REE) test also known as Resting Metabolic Rate (RMR). This test helps the individual to know with good accuracy the amount of calories needed to operate their “base systems” at rest. Knowing the number of calories needed for the body at rest will help to set the total number of calories needed per day for effective and safe weight loss.

Often times when attempting to lose weight, clients will just stop eating or eat very little thinking that will be helpful to lose weight, “if I don’t eat, I can’t gain weight”. Well, not exactly. If the body does not have enough calorie intake in a day, the systems will downshift to a lower metabolic rate and will begin to breakdown proteins into glucose molecules for energy. This leads to the dreaded breaking down of muscle and storage of fat while trying to lose weight….a no win situation.

You’ve got to eat enough calories to support the baseline systems but not overeat causing excess calorie storage….this is where knowing your calories needed at rest or Resting Energy Expenditure becomes important.

VO2 Max/Lactate-Ventilatory Threshold Testing
VO2 max has classically been described at the best indicator of cardiopulmonary fitness. In short, the “VO2 max” or “VO2 Peak” is the greatest amount of oxygen able to be exchanged during a maximal exercise event. VO2 max naturally increases with exercise training. In the endurance athlete, however, the lactate or ventilatory threshold may be a more important data point for performance improvement. During a VO2 max test, O2 consumption and CO2 production will increase together until the exercise intensity reaches the point where CO2 production increases due to the entrance of lactic acid into the bloodstream as intensity increases. This lactate acid will be buffered by sodium bicarbonate in the bloodstream producing excess CO2 which must be exhaled. During a VO2 max test, the CO2 production will increase without an increase in O2 consumption. This point is termed the lactate threshold (LT) or ventilatory threshold (VT). Once the LT/VT has been crossed fatigue will be “on the clock” as the body moves toward exhaustion.

With knowledge of the LT the athlete/coach is able to help determine the correct training intensities. With training near the LT, the athlete will typically see a “pushback” of the LT that allows for faster speeds or higher power outputs without reaching the LT.

Spin Scan
Spin Scan evaluation provides the cyclist with information regarding their pedal stroke. Commonly, cyclists are “under-utilizing” their legs during the cycling movement. A spin scan will show you where you are weak during a full revolution of the pedal. This data allows the cyclist to work on improving cycling mechanics, power, and efficiency. The spin scan is run through our Computrainer Lab system and hooks directly to your bike.

For more information and to schedule your testing, contact our Lab Coordinator, Luke Heusel, PT, OCS at the Evans facility.