Chapter 2: Exercise Physiology Flashcards
What are the 4 main components of Physical Fitness?
- Muscular (Strength & Endurance)
- Flexibility
- Cardiovascular Fitness
- Body Composition
What daily tasks require muscular strength?
Lifting and carrying objects like groceries, furniture, or suitcases
What daily tasks require muscular endurance?
Walking up stairs, shoveling snow
What are the benefits of having an adequate amount of flexibility?
- Prevents musculoskeletal injuries
- Helps maintain correct body posture
- Bending and Reaching made possible
What is the key benefit of having adequate cardiovascular aka aerobic fitness?
It lowers the risk of many common diseases such as cardiovascular disease
It also makes daily activities such as walking, biking, and swimming easier and more enjoyable
What are some diseases associated with having excess body fat?
Hypertension
Type 2 Diabetes
Coronary Artery Disease
Define Cardiorespiratory Endurance?
- The ability of the heart and lungs to deliver oxygen to the working muscles during exercise, so that carbohydrates and fatty acids can be converted to ATP for muscular contraction
- Note that the cardiovascular and respiratory systems must work together to efficiently remove metabolic waste products as well, such as CO2, lactate, and release heat
What determines oxygen-carrying capacity?
- The ability to adequately ventilate the alveoli in the lungs
- The Hemoglobin concentration in the blood
What is emphysema?
The degradation of alveoli
What is asthma?
The constriction of the breathing passages
What is anemia and how does it impair the body’s ability to use oxygen?
Anemia is a disease characterized by low hemoglobin concentration
Hemoglobin is a protein found in red blood cells that binds with oxygen so it can be carried throughout the body
People with anemia cannot carry as much oxygen in their blood so during exercise they fatigue very easily
What is the formula for cardiac output?
Cardiac Output (Q) = HR x SV
- Heart Rate x Stroke Volume
What is Ischemia?
Inadequate blood flow to the heart because of narrowed coronary arteries
The amount of oxygen extracted from the blood by the muscle for the aerobic production of ATP is dependent on what two factors?
- Muscle Fiber Type
- Availability of Specialized Oxidative Enzymes
For example, slow-twitch muscle fibers are specifically adapted for oxygen extraction and utilization due to their HIGH levels of oxidative enzymes
Where does aerobic production of ATP take place?
Inside the cell; the mitochondria
How does the body adapt to aerobic training?
- The body adapts by increasing the size and quantity of mitochondria, with a corresponding increase in oxidative enzymes
- Increase the percentage of cardiac output to the working muscles and decrease the output being sent to the viscera (non-working organs)
—> this is made possible by vasoconstriction of the non-active muscles AND the vasodilation of the active muscles (regulated by metabolites in the active muscles)
How does the Phosphagen System work to produce ATP?
Creatine Phosphate is broken down and the energy from its phosphate bond is used to reconstitute ATP by using ADP and the phosphate group broken off from ATP
The concentration of CP can quickly drop so this method of ATP synthesis is only used for quick bursts of energy needed for a few seconds of exercise
What is adenosine monophosphate (AMP)?
The combination of two ADP
What is anaerobic glycolysis?
Occurs within the cytoplasm of the cell, it is the incomplete breakdown of glucose (or glycogen) into PYRUVATE
PYRUVATE is then converted into lactate (when oxygen is NOT present)
Lactate is then transported out of the cell and can be used for energy by other cells in the body
1-3 minutes of activity
What is Aerobic Glycolysis (also called Oxidative Glycolysis)?
Occurs in the mitochondria, glucose is converted into PYRUVATE
PYRUVATE (with Oxygen) is converted into Acetyl CoA, which enters the Krebs Cycle.
The Krebs cycle produces enzymes NADH and FADH which fuel the electron transport system thus producing substantial ATP (and waste products CO2 and water)
What is beta oxidation?
Fatty acid oxidation occurring within the mitochondria. Needs oxygen
Catecholamines
Neurotransmitter such as epinephrine or norepinephrine; stimulate the body to adjust to the increased metabolic demands of exercise
What is the Anaerobic Threshold?
When exercise intensity is so high that the body cannot meet all of the metabolic demands of the muscles via steady-state aerobic metabolism, then the muscles have to supplement ATP production via anaerobic metabolism
Ventilatory Threshold
Point of transition between predominantly aerobic energy production to anaerobic energy production; involves recruitment of fast twitch muscle fibers and identified via gas exchange during exercise testing
How does epinephrine affect glucose during exercise?
Epinephrine causes the release of glucose from the liver (glycogenolysis) which allows blood glucose to remain elevated to provide fuel for the exercising muscles
What are the main functions of hormones in the body?
- Regulate Cellular Metabolism
- Facilitate Cardiovascular Response to exercise
- Facilitate transport across cell membranes (insulin)
- Induce secretory activity (ACTH causing the release of cortisol
- Modulate Protein Synthesis
What are the dangers associated with exercising in the heat?
- Dehydration
- Elevated HR (more than any level of exercise)
- Dangerous Body Temperature (104•F)
What is Tidal Volume?
The volume of air inspired per breath
What is stroke volume?
The amount of blood pumped from the left ventricle of the heart with each beat
Define the second ventilatory threshold (VT2)?
Metabolic marker which represents the point at which high intensity exercise no longer be sustained due to an accumulation of lactate. Also called the respiratory compensation threshold (RCT)
Define the first ventilatory threshold
Intensity of aerobic exercise at which ventilation starts to increase in a non-linear fashion in response to an accumulation of metabolic by-products in the blood
