Chapter 11 Physiology of Physical Activity Jennifer L. Caputo Chapter 11 Physiology of Physical Activity

Physiology of Physical Activity The study of acute (immediate) physiological responses to physical activity and the changes in physiological responses to chronic (repeated over time) physical activity. Exercise physiologists apply principles of biology and chemistry to understand how the body responds to physical activity; this serves as the foundation for conditioning, fitness, and rehabilitation programs.

Figure 11.1 Chapter 11 - Hoffman (2005)

What Does a Physiologist of Physical Activity Do? University professors Researchers for the military or NASA Employees of corporate fitness or hospital-based wellness programs Clinical exercise physiologists employed by hospitals in cardiac rehabilitation programs (continued) Chapter 11 - Hoffman (2005)

What Does a Physiologist of Physical Activity Do? (continued) Exercise instructors Personal trainers Strength and conditioning professionals Specialization with a particular population (older adults, children, pulmonary patients) Chapter 11 - Hoffman (2005)

Goals of Physiology To understand how to enhance physical performance To understand how to improve physical function in particular environments, such as a high temperature or high altitude To understand how physical activity and exercise improve health and fitness (continued) Chapter 11 - Hoffman (2005)

Goals of Physiology (continued) 4. To understand how exercise can be used in treating and preventing disease and alleviating symptoms of disease 5. To understand adaptations in human anatomy and physiology in response to physical activity

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Health Effects of Moderate Physical Activity Moderate physical activity is beneficial in reducing the risk of chronic diseases—heart disease, diabetes, hypertension, and colon cancer. (continued)

Health Effects of Moderate Physical Activity (continued) Significant research findings linking physical activity and health Physical Activity and Health: A Report of the Surgeon General NIH Web site JAMA article

Research Methods in Physiology of Physical Activity Laboratory Ergometers: treadmills, leg and arm cycles, and swimming flume Oxygen uptake: gas analyzers Body composition: underwater weighing, calipers, and DEXA (continued) Chapter 11 - Hoffman (2005)

Research Methods in Physiology of Physical Activity (continued) Laboratory (continued): Biochemical methods: blood samples and muscle biopsies Animal models: mammals that match humans as closely as possible; can control the subject and environment more easily and specifically Fieldwork (outside the laboratory): Technological advances have made fieldwork more practical.

Overview of Knowledge in Physiology of Physical Activity How physiological systems (cardiovascular, muscular and respiratory) respond and adapt to physical activity (single and repeated bouts) Factors that influence physiological responses (e.g., temperature, diet, and altitude) The relationship among fitness, activity, and health Chapter 11 - Hoffman (2005)

Skeletal Muscles Muscle fiber types Adaptations To anaerobic and aerobic training To resistance training Training principles, including progressive overload and specificity Chapter 11 - Hoffman (2005)

Skeletal Muscles Chapter 11 - Hoffman (2005)

Skeletal Muscles Chapter 11 - Hoffman (2005)

Cardiovascular System Cardiac output: heart rate and stroke volume Blood flow distribution Cardiorespiratory adaptations to training Chapter 11 - Hoffman (2005)

Cardiovascular System Chapter 11 - Hoffman (2005)

Cardiovascular System Chapter 11 - Hoffman (2005)

Respiratory System The respiratory system regulates the exchange of gases (including oxygen) between the external environment (air) and the internal environment (inside the body). Ventilation increases rapidly at the onset of physical activity and also as a function of exercise intensity. Training can alter the efficiency of the body to move and utilize oxygen. Chapter 11 - Hoffman (2005)

Temperature Effects Effects of exercise Effects of acclimatization Effect of increased internal heat related to increased physical activity and its impact on vasodilation of skin blood vessels and sweating

Nutritional Effects Carbohydrate intake for optimal performance and health Fluid intake for optimal performance and health Iron intake for optimal performance and health

Physical Activity, Fitness, and Health Effects of age on fitness Physical activity, fitness, and coronary heart disease Physical activity and weight control Chapter 11 - Hoffman (2005)

Physical Activity, Fitness, and Health Recommendations Improvement in cardiovascular endurance requires 20 to 60 minutes of activity at 70% to 94% of maximal heart rate, three to five days per week (see page 316). Note: Greater volumes and intensity of exercise will result in additional health and fitness benefits. Health benefits result from the accumulation of 150 minutes of physical activity in various ways, including 30 minutes 5 days per week or 50 minutes 3 days per week (see page 316).

Physiology of Physical Activity Study and Explore Acute and chronic adaptations to physical activity for performance, fitness, and health improvements Cellular and total body physiology The body’s response to physical activity related to a variety of factors (for instance, heat, environment, altitude) Variety of career opportunities Chapter 11 - Hoffman (2005)