NCCPT Nutrition and Energy Systems 2 — Questions and Answers
Question 1: Which energy system predominates during a 400-meter sprint?
- Oxidative phosphorylation
- ATP-PC system
- Glycolytic system (Correct answer)
- Beta-oxidation
Correct answer: Glycolytic system
The glycolytic system (anaerobic glycolysis) dominates during high-intensity efforts lasting 30 seconds to 2 minutes, such as a 400-meter sprint.
Question 2: What is the primary role of insulin in nutrient metabolism?
- Stimulating glucagon release
- Facilitating cellular glucose uptake (Correct answer)
- Breaking down glycogen stores
- Increasing fat mobilization
Correct answer: Facilitating cellular glucose uptake
Insulin facilitates the uptake of glucose into cells by promoting GLUT4 transporter activity, lowering blood glucose levels.
Question 3: During prolonged endurance exercise, what substrate shift occurs after glycogen depletion?
- Increased reliance on creatine phosphate
- Greater use of dietary protein for energy
- Increased fat oxidation via beta-oxidation (Correct answer)
- Shift to anaerobic glycolysis exclusively
Correct answer: Increased fat oxidation via beta-oxidation
As glycogen stores deplete during prolonged exercise, the body increasingly relies on fat oxidation (beta-oxidation) to supply acetyl-CoA for the Krebs cycle.
Question 4: Which vitamin is essential for the conversion of pyruvate to acetyl-CoA?
- Vitamin B12
- Vitamin B1 (thiamine) (Correct answer)
- Vitamin C
- Vitamin D
Correct answer: Vitamin B1 (thiamine)
Thiamine (vitamin B1) is a coenzyme required for pyruvate dehydrogenase, the enzyme that converts pyruvate to acetyl-CoA.
Question 5: What is the glycemic index (GI) of a food?
- The total grams of carbohydrate per serving
- A ranking of how quickly a food raises blood glucose relative to pure glucose (Correct answer)
- The ratio of simple to complex carbohydrates in a food
- The insulin response elicited per gram of carbohydrate
Correct answer: A ranking of how quickly a food raises blood glucose relative to pure glucose
The glycemic index ranks foods on a scale of 0–100 based on how rapidly they raise blood glucose compared to pure glucose (GI=100).
Question 6: Which of the following best describes the function of coenzyme A (CoA)?
- It donates electrons to the electron transport chain
- It carries acetyl groups into the Krebs cycle (Correct answer)
- It phosphorylates ADP to form ATP
- It transports fatty acids across the mitochondrial membrane
Correct answer: It carries acetyl groups into the Krebs cycle
Coenzyme A acts as an acyl carrier, binding acetyl groups to form acetyl-CoA, which then enters the Krebs cycle for energy production.
Question 7: A personal trainer's client wants to maximize muscle protein synthesis after resistance training. What post-workout nutrition strategy is most supported by research?
- High-fat meal within 3 hours post-exercise
- 20–40 g of high-quality protein within 1–2 hours post-exercise (Correct answer)
- Fast for 2 hours to enhance growth hormone secretion
- Consume only branched-chain amino acids, avoiding whole protein sources
Correct answer: 20–40 g of high-quality protein within 1–2 hours post-exercise
Consuming 20–40 g of high-quality protein (rich in essential amino acids) within 1–2 hours post-resistance training maximally stimulates muscle protein synthesis.
NCCPT Nutrition and Energy Systems 2
Which energy system predominates during a 400-meter sprint?