CSSD Sports Nutrition Planning & Performance Optimization 4 — Questions and Answers
Question 1: Creatine monohydrate supplementation most directly enhances performance in which type of exercise?
- Continuous aerobic exercise lasting more than 60 minutes
- Repeated high-intensity short-duration bouts with brief recovery periods (Correct answer)
- Low-intensity endurance activities at 40-50% VO2max
- Static flexibility training
Correct answer: Repeated high-intensity short-duration bouts with brief recovery periods
Creatine supplementation increases phosphocreatine availability, most benefiting repeated high-intensity, short-duration activities by accelerating ATP resynthesis between bouts.
Question 2: An athlete completing a 2-hour run loses 1.5 kg of body weight. Assuming losses are primarily sweat, approximately how much fluid should be consumed to achieve full rehydration?
- 1.0 L
- 1.5 L
- 2.0-2.3 L (Correct answer)
- 3.0-3.5 L
Correct answer: 2.0-2.3 L
Rehydration guidelines recommend consuming 1.25-1.5 times the fluid lost; 1.5 kg loss × 1.5 = approximately 2.0-2.3 L to account for ongoing urinary losses.
Question 3: Which micronutrient deficiency is most commonly associated with impaired oxygen transport and reduced endurance performance in female athletes?
- Vitamin D
- Iron (Correct answer)
- Calcium
- Magnesium
Correct answer: Iron
Iron deficiency (with or without anemia) impairs hemoglobin synthesis and oxygen-carrying capacity, directly reducing aerobic endurance performance.
Question 4: A sports dietitian recommends sodium bicarbonate to a competitive swimmer before a 200m race. What is the primary mechanism of action?
- Increasing muscle glycogen availability
- Buffering extracellular acidosis to delay fatigue (Correct answer)
- Enhancing creatine phosphate resynthesis
- Increasing fat oxidation during sprinting
Correct answer: Buffering extracellular acidosis to delay fatigue
Sodium bicarbonate acts as an extracellular buffer, increasing blood pH and facilitating efflux of hydrogen ions from muscle, thereby delaying fatigue during high-intensity exercise.
Question 5: During a 4-hour ultramarathon in the heat, which electrolyte loss is most likely to contribute to hyponatremia if the athlete consumes large volumes of plain water?
- Potassium
- Magnesium
- Sodium (Correct answer)
- Calcium
Correct answer: Sodium
Hyponatremia during prolonged exercise results from excessive sweat sodium losses combined with over-consumption of hypotonic fluids, diluting serum sodium below 135 mEq/L.
Question 6: What is the recommended carbohydrate intake during the classic carbohydrate-loading protocol in the 24-48 hours before a marathon?
- 3-5g/kg/day
- 5-7g/kg/day
- 8-12g/kg/day (Correct answer)
- 15-20g/kg/day
Correct answer: 8-12g/kg/day
Evidence-based carbohydrate loading protocols recommend 8-12g of carbohydrate per kilogram of body weight per day in the 24-48 hours prior to prolonged endurance events.
Question 7: A dietitian advises an athlete on nitrate supplementation via beetroot juice. What is the proposed ergogenic mechanism?
- Increased testosterone secretion during exercise
- Conversion to nitric oxide, improving oxygen efficiency and blood flow (Correct answer)
- Direct glycogen sparing through insulin sensitization
- Enhanced carnosine synthesis in fast-twitch muscle fibers
Correct answer: Conversion to nitric oxide, improving oxygen efficiency and blood flow
Dietary nitrates are reduced to nitric oxide in vivo, which vasodilates blood vessels, reduces the oxygen cost of exercise, and may enhance mitochondrial efficiency.
CSSD Sports Nutrition Planning & Performance Optimization 4
Creatine monohydrate supplementation most directly enhances performance in which type of exercise?