NASM Ch 8 Exercise Metabolism and Bioenergetics

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 physiologic changes and demands placed on the body during exercise.

carbs, fats, etc

what components are considered chemical energy?

carbon dioxide and water

what components are considered chemical waste?

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 protein, carbohydrate, and fat.

the molecular bonds of carbs, fat, and protein

Energy is stored in the human body in the same way it is contained within food which is

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.

mostly glucose

As the intensity of an activity increases, the body transitions from using mostly fat as fuel to using

oxygen

glucose can also be metabolized without _ , whereas using fat for fuel always requires _.

50

As activity intensity increases, the usage of carbohydrate as an energy source becomes %, and the usage of fat becomes %?

ventilatory threshold 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 of the energy for the activity.

fats

One of the three main classes of foods and a source of energy in the body. Fats help the body use some vitamins and keep the skin healthy. They also serve as energy stores for the body. In food, there are two types of fats: saturated and unsaturated

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.

cardiorespiratory assessment

VT1 is an important concept relating to what?

VT1

what maximizes both fat loss goals and performance goals for clients?

VT2

when intensity increased further to maximal levels

during rest and lower-intensity exercise below vt1

During what types of activity are fats (lipids) the primary energy source?

Triglycerides.

What is the chemical form in which most fats exist in food and in the body?

free fatty acids (FFAs)

What are triglycerides commonly called when they are circulating in the bloodstream?

fats eaten in food and stored body fat

Where do free fatty acids come from?

triglycerides must be broken down into free fatty acids

Before fat can be used for energy, what must happen first?

The aerobic metabolic pathway only.

Which metabolic pathway uses free fatty acids to produce ATP?

Because even lean individuals have large fat stores that can provide energy during prolonged, low-intensity exercise.

Why are fats an excellent long-term energy source?

FFAs

What is the primary fuel source when exercising below VT1?

3500 cals

1lb of body fat is equal to?

20 amino acids

how many amino acids are in the human body?

9 amino acids

how many amino acids are essentials and received via diet?

nonessential amino acids

Amino acids that can be synthesized by the body and do not, under normal circumstances, need to be obtained in the diet.

negative energy balance

When calorie intake is lower than the number of calories expended.

gluconeogenesis

The formation of glucose from noncarbohydrate 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.

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.

the human body as long as overall nutrition intake is adequate

nonessential amino acids are synthesized how?

acetone, acetoacetic acid, and beta-hydroxybutyric acid

ketone bodies contain these three molecules

heavily restricting calories, low carb diets, consuming exogenous ketones, and lack of insulin

how are ketone levels in the body increased?

0.5–1.5 millimoles per liter (mmol/L) of blood

ketone levels can increase to approximately _ ,which is known as nutritional ketosis