# A sports nutrition company claims that athletes need to increase their intake of protein, carbohydrates and iron compared to non-athletes. Explain why each of these three nutrients is particularly important for an athlete's body.

> OCR A-Level Biology B — Advancing Biology (H422) — 2.3 Diet, nutrition and health · Explain · 5 marks

> Athletes train intensively and their bodies undergo significant physiological demands, including muscle repair, sustained energy release and efficient oxygen transport during exercise.

## Mark scheme (5 marks)

1. Protein is needed for growth and repair of muscle cells / tissues
2. Carbohydrates are the main source of energy / provide energy for muscle contraction and exercise
3. Iron is needed to make haemoglobin in red blood cells
4. Haemoglobin / red blood cells carry oxygen to the muscles, so more iron means more efficient oxygen delivery during exercise
5. An athlete has a higher demand for all three nutrients because their muscles are working harder / being damaged and repaired more frequently / energy is used at a greater rate

## Key terms

- [protein](https://www.gradenine.co.uk/glossary/protein)
- [carbohydrates](https://www.gradenine.co.uk/glossary/carbohydrates)
- [iron](https://www.gradenine.co.uk/glossary/iron)

## Related

- [Revision notes for OCR A-Level Biology B — Advancing Biology (H422)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-sports-nutrition-company-claims-that-7605d84f) · Published by Druglandscape Ltd.