Due to the nature of our trip; its long length and the short time-frame, we feel that we have a unique opportunity to study different aspects of the human body and its response to such an undertaking.
The body can respond in several ways to prolonged exercise. Most of the time, increased exercise leads to increased fitness. However, without proper recovery, the body may experience certain changes where fitness actually decreases, and thus athletic ability declines. This condition is known as “overtraining,” and is of great interest to athletes and coaches, who want to avoid reaching this state during long-term training and exercise. Overtraining has been historically difficult to study, and there have been very few long-term studies to look at specific markers, or “signs,” that the body can give warning the athlete of his or her reaching this state.
As such, we are studying the physiological effects of strenuous exercise on the human body. When you exercise, your body produces certain stress hormones that help your body both deal with the stress of the exercise and to heal itself during recovery periods. We have designed a study to look at two such hormones: cortisol and testosterone, by measuring these chemicals in our own bodies. To do so, we are carrying salivettes, which are, in essence, test tubes that we salivate into every week. We then overnight these tubes back to our lab with Dr. David Hostler in the Department of Emergency Medicine at UPMC, where they are centrifuged and frozen. After returning from the trip these samples will be analyzed using molecular techniques to determine the levels of the hormones throughout our trip. These hormones will be correlated with other data about our bodies, including awakening heart rate, blood pressure, and fasting glucose.
Additionally, and as you well know, the body’s response to exercise is increased fitness. There are many ways to measure fitness, and we will be doing fitness tests both in a laboratory setting and out here in the field. In the lab, we will be measuring our lung’s capacity to carry oxygen (VO2), the rate at which our muscles clear lactic acid (lactate threshold), as well as the power we can generate with our legs (wattage). Many thanks go to Dr. John Abt and Gordon Huang at the Neuromuscular Research Lab at UPMC, as well as Dr. Tripps at Swedish Medical Center Sports Performance Services, for their support of our project and their generous gift of laboratory time.
We will also be measuring heart rate fluctuations and power in the field during our trip. Thanks to SRM Powermeters, we have three professional grade cycling ergometers which will be able to measure, with high sensitivity, our performance and fitness out in the field. Using GPS, we are selecting time-trial courses out in the mountains of the Pacific Northwest and Canada to run tests once a week that will show our performance on a week to week basis.
Hopefully we will return with some very interesting data. If anything, we are all experiencing first-hand what it is like to run field tests – in all its frustrations and glory!