1. Homeostasis
the maintenance of a constant or unchanging internal environment
during rest or unstressed conditions

2. Steady State constant internal environment or metabolism
during exercise or elevated metabolism
balance has been achieved between demands of the body and the body’s response

3. Changes in body core temperature during exercise in thermoneutral environment

4. Temperature core temperature is a very important metabolic parameter
needs to be maintained within a very narrow range
much heat is generated during exercise, but is dissipated to maintain constancy
homeostatic condition will not differ from steady state greatly

5. Changes in arterial blood pressure across time during rest

6. Blood Pressure blood pressure is another important metabolic parameter
will vary to a greater extent from rest to exercise
will be constant during homeostasis or steady state though

7. A thermostat controlled heating/cooling system

8. Components that comprise a biological control system

9. Components Stimulus-excites a receptor Receptor-receives the stimulus
Integrating center-relay station (dispatcher)
Effector-corrects disturbance and removes stimulus

10. Negative Feedback Biological control system
effector response opposite to stimulus
very common in biological systems

11. Example of negative feedback mechanism to lower blood pressure

12. Regulation of blood glucose concentration

13. Exercise as a Test of Homeostasis
During exercise
Heart rate can increase 4-5 fold
Systolic BP can increase 2-3 fold
Core temperature remains relatively constant
Blood glucose remains stable for prolonged periods
Body possesses wide range of homeostatic mechanisms which counteract physiological stressors