Nutrition Science Foundations
What this domain tests
Nutrition Science Foundations checks whether you can explain energy balance, macronutrient roles and dosing, micronutrient and fiber needs, digestion and absorption, hydration, nutrient timing, and supplement risk at the sports-nutrition-coach level. You apply science; you do not diagnose or prescribe therapeutic diets.
Core rules
- Energy balance drives weight change; macronutrient distribution shapes body composition, performance, and adherence.
- Protein: roughly 1.2–2.0 g/kg/day for training clients, spread across 3–5 feedings; use higher ends for resistance training and energy restriction.
- Carbohydrate: scale to training load-commonly 3–5 g/kg/day for moderate training and 6–10 g/kg/day for heavy endurance work.
- Fat: about 20–35% of energy; chronic very-low-fat intake can impair hormone function and fat-soluble vitamin status.
- Fiber: 25–38 g/day for general health, timed away from immediate pre- or intra-workout meals.
- Digestion: most protein and carbohydrate absorption occurs in the small intestine; fiber is fermented in the colon.
- Hydration: start euhydrated; about 5–10 mL/kg body mass 2–4 hours before exercise, then replace sweat losses.
- Supplements: food first, third-party testing, and caution with stimulants, proprietary blends, and banned substances.
Worked example
A 70 kg athlete needs about 2,800 kcal. Protein at 1.6 g/kg = 112 g (448 kcal). Fat at 25% = 700 kcal ÷ 9 = 78 g. Carbohydrate = 2,800 − 448 − 700 = 1,652 kcal ÷ 4 = 413 g, or about 5.9 g/kg. Reasoning: set protein and fat first, then fill remaining energy with carbohydrate to support training.
Traps
- Mixing g/kg dosing with percentage-of-calories targets.
- Assuming nutrient timing outweighs total intake.
- Pushing very low carbohydrate or fat without a performance rationale.
- Missing low energy availability and RED-S warning signs.