Chapter 8: Exercise Metabolism and Bioenergetics

adenosine triphosphate (ATP)

serves as main form of cellular energy in the body

bioenergetics

study of how energy is transformed through various biochemical reactions

metabolism

chemical reactions in the body that occur in the body to maintain itself

exercise metabolism

looks at bioenergetics as it relates to the physiologic changes and demands placed on the body during exercise

first law of thermodynamics

energy cannot be created nor destroyed only converted from one form to another

macronutrients

taking in food (large amounts) that supply energy including protein, carbohydrates, and fats

substrates

immediate forms of nutrients (digestive by-products) used in metabolic reactions to create ATP

glucose

main energy source for the brain and high-intensity activity (simplest form of energy)

glycogen

glucose that is stored in the body’s tissues (liver and muscle cells)

fuel for rest

fats

fuel for moderate and intense activity

glucose (more easily accessible)

ventilatory threshold 1

a metabolic marker when the body uses 50% fat and 50% carbohydrates as energy when activity increases

ventilatory threshold 2

marker where glucose provides almost all of the energy

fats

used as energy for rest and low intensity exercise. They help the body use vitamins and keep the skin healthy

tryglyceride

form of fat as it exists in the body

free fatty acids

why triglycerides are broken down and in the blood stream ready to be used for energy, used to make ATP

amino acids

the makeup of protein and the third source of energy

essential amino acids

can’t be synthesized by the body

negative energy balance

when caloric intake is lower than caloric expenditure

gluconeogenesis

synthesis of glucose from noncarbohydrate sources (fats & proteins)

ketogenesis

formation of ketone bodies from non-fate sources (amino acids)

ketone bodies

used to create ATP when oxidized and they are produced in the liver during fatty acid oxidation

ketosis

carbohydrate depletion when liver keeps making ketone bodies to support exertion but there are not enough fatty acids

exogenous ketones

isolated ketone bodies (supplement form)

insulin resistance

inability to respond to insulin (eating habits that spice glycemic levels too often)

ketoacidosis

too high ketone body levels (seen in type 1 diabetes or severe insulin resistance)

how many calories = 1lb of body fat

3,500 calories