Chapter 8: Exercise Metabolism And Bioenergetics Flashcards
Adenosine triphosphate (ATP)
A high- energy molecule that serves as the main form of energy in the human body; known as the energy currency of the body.
Bioenergetics
The study of energy in the human body
Metabolism
All of the chemical reactions that occur in the body to maintain itself.
Exercise metabolism
The examination of bioenergetics as it relates to the unique physiological changes and demands placed in the body during exercise.
First law of thermodynamics
Energy cannot be created or destroyed but merely converted from one form to another.
Macronutrients
Food substances required in large amounts to supply energy and include protien, carbs and fat.
All life on earth is?
Carbon based
The “energy” contained in food is located?
Within the molecular bonds
How is carbon removed from the body?
Exhaling co2 is the only way carbon is removed from the body
Substrates
Intermediate forms of nutrients used in metabolic reactions to create adenosine triphosphate.
Glucose
The simplest form of carbohydrate used by the body for energy.
Glycogen
Glucose that is deposited and stored in bodily tissues, such as the liver and muscle cells; the storage form of carbohydrate.
What primarily fuels the body when it is not active?
Fats
Ventilatory threshold 1 (VT1)
The point at which the body uses an equal mix of carbohydrate and fat as fuel sources.
Ventilatory threshold 2 (VT2)
The point where glucose provides nearly all the energy for the activity.
Triglyceride
The chemical or substrate form in which most fat exists in food as well as in the body.
Free fatty acids
The by-products of the breakdown of stored or consumed fats, metabolized exclusively via the aerobic pathway, which uses oxygen to create adenosine triphosphate.
Protein
Amino acids linked by peptide bonds; the building blocks of body tissues.
Essential amino acids (EAA)
Amino acid that must be obtained through the diet as the body does not make it; there are nine essential amino acids.
Benefits of having fat as a fuel source?
Even relatively lean people still have a large supply stored on their body, which can be broken down into triglycerides and used for energy during prolonged, lower intensity physical activity and exercise.
What is the primary fuel source when an individual is exercising at an intensity below VT1?
Free fatty acids
Before amino acids can be used to make ATP, they are further broken down and then recombined into?
Either glucose through a process called gluconeogenesis or ketone bodies through a process called ketogenesis.
Gluconeogenesis
The formation of glucose from non carbohydrate sources (proteins and fats)
Ketogenesis
The formation of ketone bodies from nonfat sources, such as certain amino acids.
Ketone bodies
Water-soluble molecules produced in the liver as a result of fatty acid oxidation. They can then be oxidized in the mitochondria to produce adenosine triphosphate (ATP)
Ketosis
A state of carbohydrate depletion where the liver manufactures ketone bodies to meet energy demands that free fatty acid oxidation cannot support.
Exogenous ketones
Isolated ketone bodies usually consumed in supplement form.
Insulin resistance
The inability of the cells to respond to insulin; occurs in type 2 diabetes
Ketoacidosis
Metabolic acidosis induced by very high levels of ketone bodies such as seen in type 1 diabetes or severe insulin resistance.
What three molecules are in a keytone body?
- Acetone
- Acetoacetic acid
- Beta-hydroxybutyric acid
Ketone levels can increase to approximately .5-1.5 millimoles per liter (mmol/L) of blood, which is known as?
Nutritional ketosis
How many calories equal 1 pound of body fat?
3,500