Exercise physiology can be defined as the scientific study of what is happening inside the body due to exercise (physical activity). More specifically, exercise physiology is the study of cued-responses to exercise and the adaptations that occur with training; a short-term change is called a response and a long-term change causing a relatively permanent change in structure or function is referred to as an adaptation.
Exercise can be defined as a single session of physical activity that is at least of moderate intensity. Therefore, leisure walking is not an exercise; it’s a physical activity! Training is the systematic grouping of exercises (e.g. jogging 4x/week; not once a week).
Exercise Response
An exercise response occurs when there is:
- an increase in heart rate
- increase in heart’s contractility
- increase in depth & breathing
- increase in sweating
- a redistribution of blood flow
- mobilization of fuel supply
Exercise responses permit the athlete to work out and they are designed to reverse the direction of the homeostatic disturbances (explained shortly).
Training Adaptation
A training adaptation (relatively permanent) occurs when:
- the blood volume increases
- an increase in the size of a cell (hypertrophy) occurs
The magnitude of an exercise response/adaptation varies depending on the intensity, duration, and nature of the exercise. Exercise responses and training adaptation exhibit a negative feedback loop, where the body attempts to reverse the direction of the homeostatic disturbance.
In exercise physiology emphasis is be given to “how” an adaptation occurs rather than “why”. By understanding how an adaptation occurs one can better predict, control, and improve the adaptation; often times the objective of studying exercise physiology is improving performance!
Picture Credit
© by Mark Howard Photography @ Flickr
http://www.flickr.com/photos/markhowardphotography/