CSSD Hydration Strategies 2 — Questions and Answers
Question 1: An endurance cyclist is training in 35°C heat for 3 hours. Which electrolyte replacement strategy is most appropriate?
- Water only to avoid GI distress
- Sodium-containing beverage (500–700 mg/L) consumed regularly (Correct answer)
- Hypertonic sports drink consumed only at the finish
- Potassium supplements taken pre-exercise
Correct answer: Sodium-containing beverage (500–700 mg/L) consumed regularly
Sodium-containing fluids help replace sweat sodium losses, maintain plasma osmolality, and stimulate thirst during prolonged exercise in heat.
Question 2: Which urine specific gravity (USG) value best indicates adequate hydration before an athletic event?
- 1.030 or higher
- 1.025–1.029
- 1.020–1.024
- 1.001–1.020 (Correct answer)
Correct answer: 1.001–1.020
A USG of 1.001–1.020 indicates euhydration, while values above 1.020 suggest significant dehydration.
Question 3: A football lineman sweats at a rate of 2.5 L/hr during two-a-day practices. What is the primary concern beyond fluid replacement?
- Carbohydrate depletion
- Sodium and chloride losses leading to hyponatremia risk if overdrinking water (Correct answer)
- Protein catabolism from sweat
- Vitamin C depletion
Correct answer: Sodium and chloride losses leading to hyponatremia risk if overdrinking water
High-volume sweaters who replace losses with plain water risk dilutional hyponatremia; sodium replacement is critical.
Question 4: Which method is considered the gold standard for assessing sweat rate in athletes?
- Urine color chart
- Pre- to post-exercise body weight change (Correct answer)
- Plasma osmolality measurement
- Bioelectrical impedance analysis
Correct answer: Pre- to post-exercise body weight change
Pre-to-post exercise nude body weight change (corrected for fluid intake and urine output) is the most practical and accurate field measure of sweat rate.
Question 5: An athlete competing in a 2-hour half-marathon in cool (15°C) conditions reports drinking 1.5 L every 30 minutes. What risk should the CSSD prioritize?
- Severe dehydration
- Exercise-associated hyponatremia (EAH) (Correct answer)
- Hyperkalemia
- Heat exhaustion
Correct answer: Exercise-associated hyponatremia (EAH)
Drinking in excess of sweat rate, especially with hypotonic fluids, dilutes serum sodium and can cause exercise-associated hyponatremia.
Question 6: Which carbohydrate-to-sodium ratio in a sports drink best promotes intestinal fluid absorption during exercise?
- High carbohydrate (>10%), no sodium
- 6–8% carbohydrate with 20–30 mmol/L sodium (Correct answer)
- 2% carbohydrate with 80 mmol/L sodium
- Isotonic glucose-only solution
Correct answer: 6–8% carbohydrate with 20–30 mmol/L sodium
A 6–8% carbohydrate solution with 20–30 mmol/L sodium optimizes co-transport absorption in the small intestine via the SGLT1 pathway.
Question 7: A wrestler is cutting weight for competition and uses a sauna to lose 3% body weight in 24 hours. What is the most likely performance consequence?
- Improved muscular endurance due to heat acclimatization
- Impaired strength, power, and cognitive function (Correct answer)
- Increased VO2max through plasma volume expansion
- No performance effect if rehydrated 1 hour before weigh-in
Correct answer: Impaired strength, power, and cognitive function
A 3% body weight deficit significantly impairs muscular strength, anaerobic power, and cognitive performance, effects that persist even with partial rehydration.
CSSD Hydration Strategies 2
An endurance cyclist is training in 35°C heat for 3 hours.
Which electrolyte replacement strategy is most appropriate?