CSSD Micronutrient Needs in Athletes 1 — Questions and Answers
Question 1: Which form of dietary iron has the highest bioavailability in athletes?
- Non-heme iron from plant sources
- Heme iron from animal sources (Correct answer)
- Ferrous sulfate from fortified cereals
- Iron from legumes and seeds
Correct answer: Heme iron from animal sources
Heme iron from animal sources is absorbed at 15–35%, far exceeding the 2–20% absorption rate of non-heme iron from plant foods.
Question 2: What is the primary physiological role of vitamin D relevant to athletic performance?
- Reducing blood lactate accumulation during exercise
- Optimizing glycogen storage in muscle
- Supporting calcium absorption and muscle protein synthesis (Correct answer)
- Directly enhancing maximal aerobic capacity
Correct answer: Supporting calcium absorption and muscle protein synthesis
Vitamin D facilitates intestinal calcium absorption and plays a role in muscle protein synthesis and neuromuscular function, making it critical for bone health and muscle performance.
Question 3: Which serum marker is the most sensitive indicator of iron stores in an athlete?
- Hemoglobin
- Serum iron
- Ferritin (Correct answer)
- Mean corpuscular volume (MCV)
Correct answer: Ferritin
Serum ferritin reflects total body iron stores and is the earliest marker to decrease in iron depletion, though it can be falsely elevated during acute inflammation.
Question 4: Female endurance athletes are at elevated risk for iron deficiency primarily due to which combination of factors?
- Reduced intestinal iron absorption and high-protein diets
- Menstrual iron losses, foot-strike hemolysis, and sweat iron losses (Correct answer)
- Low dietary protein and excessive antioxidant supplementation
- Increased hepcidin production and calcium supplementation
Correct answer: Menstrual iron losses, foot-strike hemolysis, and sweat iron losses
Female endurance athletes face multiple routes of iron loss including menstruation, mechanical hemolysis from foot-strike, gastrointestinal micro-bleeding, and sweat losses.
Question 5: What is the generally recommended daily calcium intake for adult athletes to support bone health?
- 500–700 mg/day
- 800 mg/day
- 1000–1300 mg/day (Correct answer)
- 1600–2000 mg/day
Correct answer: 1000–1300 mg/day
Adult athletes are advised to consume 1000–1300 mg of calcium daily, aligned with general population DRIs, to support bone remodeling under the stress of regular training.
Question 6: Sports anemia (dilutional pseudoanemia) in endurance athletes is best characterized by:
- Low serum ferritin and low hemoglobin due to iron depletion
- Apparent low hemoglobin due to plasma volume expansion with normal iron stores (Correct answer)
- Megaloblastic changes from vitamin B12 deficiency
- Hemolysis from excessive antioxidant supplementation
Correct answer: Apparent low hemoglobin due to plasma volume expansion with normal iron stores
Endurance training increases plasma volume proportionally more than red cell mass, diluting hemoglobin concentration without true iron deficiency—serum ferritin remains normal.
Question 7: Which component is NOT part of the original Female Athlete Triad as classically defined?
- Low energy availability
- Menstrual dysfunction
- Low bone mineral density
- Iron deficiency anemia (Correct answer)
Correct answer: Iron deficiency anemia
The classic Female Athlete Triad consists of low energy availability, menstrual dysfunction, and low bone mineral density; iron deficiency anemia is a related but separate condition.
CSSD Micronutrient Needs in Athletes 1
Which form of dietary iron has the highest bioavailability in athletes?