Question 1

The main energy fuel during heavy exercise such as competitive running is&#10;A) carbohydrate&#10;B) lipid&#10;C) protein&#10;D) sodium

Accepted Answer

During heavy exercise such as competitive running, the main energy fuel used by the body is carbohydrate. Carbohydrates are broken down into glucose, which is then utilized to produce ATP (adenosine triphosphate), the primary energy currency of the cell, through glycolysis and oxidative phosphorylation. This process provides the quick energy required for high-intensity activities.

Question 2

Energy from the intramuscular high-energy phosphates (i.e., ATP and CP) can sustain all-out exercise for&#10;A) ~10 seconds&#10;B) 2-3 minutes&#10;C) 20 minutes&#10;D) 1 hour

Accepted Answer

Energy from intramuscular high-energy phosphates, specifically ATP and creatine phosphate (CP), can sustain all-out exercise efforts for only a very short duration, approximately 10 seconds, before depletion occurs and other energy systems must take over.

Question 3

Which of the following does not explain why carbohydrate is a better energy fuel than fat?&#10;A) Carbohydrate can be metabolized for energy both anaerobically and aerobically&#10;B) ATP production from carbohydrate breakdown is faster&#10;C) Burning fat needs the presence of carbohydrate&#10;D) One molecule of glucose once broken down aerobically can produce much more ATPs than a fatty acid molecule

Accepted Answer

D is incorrect because one molecule of glucose produces less ATP compared to a fatty acid molecule when both are broken down aerobically. Fatty acids, being longer carbon chains, yield more ATP upon oxidation than glucose.

Question 4

In which of the following circumstances will protein be most likely used as an energy fuel?&#10;A) Immediately following a meal&#10;B) During brisk walking&#10;C) After 24 hours of starvation&#10;D) During time between regular meals

Accepted Answer

Protein is most likely used as an energy fuel after 24 hours of starvation because the body's carbohydrate stores become depleted, and it starts to break down protein for energy.

Question 5

What is the predominant energy system used for an 800-m run?&#10;A) ATP-CP&#10;B) Anaerobic glycolysis&#10;C) Aerobic system

Accepted Answer

The 800-m run primarily relies on anaerobic glycolysis because it is a middle-distance event that requires sustained high-intensity effort, typically lasting around 1.5 to 2 minutes, which is too long for the ATP-CP system and too short for the aerobic system to be the predominant energy source.

Question 6

What is the predominant energy system used for a 10-km run?&#10;A) ATP-CP&#10;B) Anaerobic glycolysis&#10;C) Aerobic system

Accepted Answer

The aerobic system is the primary source of energy for activities lasting longer than a couple of minutes, such as a 10-km run, because it efficiently produces ATP through the breakdown of carbohydrates and fats in the presence of oxygen.

Question 7

Which of the following is what trained athletes are able to do to better budget their fuels during prolonged endurance exercise?&#10;A) Use more protein to spare carbohydrate&#10;B) Use more carbohydrate to spare fat&#10;C) Use more fat to spare carbohydrate&#10;D) Use more protein to spare fat

Accepted Answer

Trained athletes are able to use more fat to spare carbohydrate during prolonged endurance exercise. This adaptation allows them to conserve their limited carbohydrate stores (glycogen) for later stages of exercise, enhancing their endurance performance.

Deck 6: Digestion and Absorption