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Discuss "WHY" carbohydrate is the preferred fuel source during endurance exercise.

A diet rich in carbohydrates increases both endurance and intermittent high-intensity performance because of the extra store of carbohydrates in the muscles and liver, called glycogen. More glycogen that can be restored into the muscles usually will give the athlete to last longer during prolonged exercise. It is well documented that athletes need to replenish carbohydrate stores in the body, especially during periods of intense training or competition. Consuming carbohydrates during workouts lasting over one hour can also benefit performance and delay onset of fatigue.

What effect do the catecholamines have on glycogen and lipids?

Catecholamines stimulate glycogenolysis and lipolysis

Differentiate between endocrine and exocrine gland structure. Name two endocrine and two exocrine glands (not secretion type, e.g., holocrine)?

Endocrine: contain no ducts (ductless glands) and secrete substances directly into extracellular spaces around the gland ○ Exocrine: contain secretory ducts that carry substances directly to a specific compartment or surface and almost all of these glands are controlled by the nervous system sweat glands, upper digestive tract glands

Discuss oxygen deficit and debt.

Oxygen deficit quantitatively expresses the difference between the total oxygen consumption during activity and the total that would be consumed had steady-state oxygen consumption been achieved at onset. Represents immediate anaerobic energy transfer from the hydrolysis of intramuscular high-energy phosphates and glycolysis until steady-rate energy transfer meets current energy demands. Oxygen debt is a cumulative deficit of oxygen available for oxidative metabolism that develops during periods of intense bodily activity and must be made good when the body returns to rest.

Comprehensively discuss the three energy-producing pathways.

These systems work together to keep producing ATP Phosphagen (immediate source)- also called the CrP-ATP system) is the quickest way to resynthesize ATP. Creatine phosphate (CrP), which is stored in skeletal muscles, donates a phosphate to ADP to produce ATP. During rest the ATP will help to restore CrP. Anaerobic (somewhat slow, uses carbohydrates)- The anaerobic lactic system runs without requiring oxygen and burns glucose (carbohydrates) as its preferred fuel. It's not as powerful as the ATP-PC system, but it can produce a relatively high proportion of Adenosine Triphosphate (ATP) for around 30seconds before quickly starting to plateau as energy production decreases significantly between 30-90seconds. The primary role of the lactic system is to generate higher levels of force and power over longer periods of time than the phosphocreatine system. Aerobic (slow, uses either carbohydrate or fat)- relies on the circulatory system (breathing in oxygen) in order to create adenosine triphosphate (ATP) for energy use. It also uses fats, glucose, carbohydrates and proteins. The aerobic system can be divided into three processes: Aerobic glycolysis (slow glycolysis)- During aerobic (slow) glycolysis, glycogen is converted to glucose .A series of enzymes then break down the glucose to create Pyruvate. Pyruvate then gets converted into acetyl coenzyme A as oxygen becomes present. Krebs cycle (citric acid cycle)- During the Krebs cycle, acetyl coenzyme A is broken down even more to create carbon dioxide and hydrogen. Hydrogen combines with two enzymes and is transported to the electron transport chain where the acidity levels are controlled. Electron transport chain- producing 34 ATP molecules for every molecule of glucose that is used. Hydrogen ions are carried to the electron transport chain by carrier molecules. They are then transferred to carrier molecules embedded in the electron transport chain where they undergo a series of chemical reactions. A hydrogen ion gradient is created. As these ions move across this gradient, ATPase phosphorylates ADP is formed to create ATP.

Describe the components of total daily energy expenditure.

Total daily energy expenditure is the product of basal metabolic rate and physical activity level. Basal metabolic rate is the number of calories required to keep your body functioning at rest. Physical activity level is the amount of physical exertion in one day determines how many calories must be consumed in the same period to maintain activity and lose or gain weight as desired.