Sports Nutrition & Exercise Physiology Flashcards

Which energy system provides the primary fuel source during a 400-meter sprint lasting approximately 45–60 seconds?

Answer: Glycolytic system

The glycolytic system (anaerobic glycolysis) is the predominant energy pathway for high-intensity efforts lasting roughly 30–120 seconds, such as a 400-meter sprint.

Current evidence-based protein recommendations for strength-trained athletes seeking muscle hypertrophy suggest a daily intake of approximately:

Answer: 1.6–2.2 g/kg body weight

Research consistently supports 1.6–2.2 g/kg/day as the effective range for maximizing muscle protein synthesis in resistance-trained individuals.

A competitive cyclist plans to compete in a 3-hour road race. Which carbohydrate strategy best supports endurance performance during the event?

Answer: Consume 60–90 g carbohydrate per hour from multiple transportable carbohydrate sources

Multiple transportable carbohydrates (e.g., glucose + fructose) can be oxidized at up to 90 g/hr, sparing glycogen and sustaining high-intensity output during prolonged endurance events.

The American College of Sports Medicine recommends athletes drink enough fluid during exercise to prevent body weight loss exceeding:

Answer: 2% of body weight

Dehydration exceeding 2% of body weight measurably impairs aerobic performance and cognitive function, making this the commonly cited threshold for significant performance decrements.

Which of the following female athletes is at GREATEST risk for developing iron-deficiency anemia?

Answer: An elite distance runner training 80 miles per week on hard surfaces

Elite distance runners face compounding iron-loss factors: high menstrual losses, foot-strike hemolysis, GI blood loss, hepcidin elevation post-exercise, and heavy sweat losses.

Creatine monohydrate is most well-supported by evidence for enhancing performance in which type of activity?

Answer: Repeated short bouts of high-intensity exercise (e.g., sprint intervals)

Creatine supplementation increases phosphocreatine stores, supporting rapid ATP resynthesis and improving performance in repeated short bouts of maximal or near-maximal effort.

For optimal muscle glycogen resynthesis after exhaustive endurance exercise, what is the recommended carbohydrate intake during the first 4 hours of recovery?

Answer: 1.0–1.2 g/kg/hr

Consuming approximately 1.0–1.2 g of carbohydrate per kg body weight per hour during the first 4 hours post-exercise maximizes glycogen synthase activity and restores muscle glycogen rapidly.