Principles of nutrition

Question 1

What is the definition of nutrition?

Answer 1

The provision of nourishment to cells, tissues, organs, systems and the body as a whole

Question 2

What does nutrition encompass? (2)

Answer 2

• How food influences our body function and health

- Includes dietary guidelines, food composition and roles that various nutrients have in maintain health

Question 3

What type of curve do you get from nutrient requirements?

Answer 3

Bell curve

Question 4

What is the definition of sports and exercise nutrition?

Answer 4

The amount, composition and timing of food intake can profoundly affect sports performance

Question 5

What are the goals of sports nutrition? (8)

Answer 5

Meet the energy and fuel requirements
Maintain ideal physique
Adaptation/recovery
Refuel/hydrate
Optimal health and function
Reduce risks of sickness and injury
Eat for long term health
Enjoy food

Question 6

What are the 3 components of energy distribution?

Answer 6

Carbohydrate
Protein
Fat

Question 7

What is the composition of the average UK diet compared to healthy?

Answer 7

Protein: 20% | 15%
Carbohydrate: 40% | 60%
Fat: 40% | 25%

Question 8

What are the daily requirements of carbohydrates?

Answer 8

6-10g/kg/day - to meet energy demands

450g-750g - 75kg athlete

Question 9

What is the goal of pre-exercise feeding?

Answer 9

Optimize the supply of muscle glycogen and blood glucose late in the exercise bout

Question 10

What are the recommendations for pre-exercise CHO ingestion? (3)

Answer 10

Eat an easy to digest high CHO meal
3-4 hours before exercise
High glycemic index CHO meals

Question 11

What are the potential effects of pre-exercise CHO ingestion? (3)

Answer 11

Promote extra muscle glycogen synthesis
Replenish liver glycogen
Increase CHO oxidation during exercise

Question 12

How much CHO should you take in during exercise and what form should it be?

Answer 12

30-60g/hour

Solid and liquid forms

Question 13

Why should you take CHO during exercise and not fat or protein?

Answer 13

• Hydration, maintenance of blood glucose, muscle/liver glycogen sparing, prevention of GI distress
• Protein and fat consumed during exercise can delay gastric emptying

Question 14

What is the best carb combo to enhance performance?

Answer 14

Glucose + fructose

Question 15

Why is CHO post exercise important?

Answer 15

• Delaying CHO intake following intense exercise may reduce muscle glycogen storage and impair recovery
• First 30mins produces rapid rate of resynthesis
• Replace muscle and liver glycogen

Question 16

How much CHO should athletes consume after 2hr exercise period?

Answer 16

3g/kg/BW

Question 17

What happens in glycogen resynthesis after exercise?

Answer 17

• High/moderate glycemic index

- During/immediately post exercise (60min rapid resynth period)

Question 18

How is glycogen resynthesis increased? (5)

Answer 18

Activation of glycogen synthase induced by:
- Glycogen depletion
- Muscular contraction
- Increased insulin secretion
GLUT 4 increases translocation

Question 19

What are the protein requirements for:

a) healthy adult
b) Endurance trained
c) resistance trained

Answer 19

a) 0.75g/kg/BW
b) 1.2-1.7g/kg/BW
c) 1.4-2.0g/kg/BW

Question 20

When should you hydrate (and amount) and eat pre-exercise? (3)

Answer 20

• 400-600ml fluid 2 hrs before exercise
• Pre exercise meal 2-4hrs before exercise
• Do not sleep in dehydrated state

Question 21

How can you have optimal hydration during exercise? (5)

Answer 21

• Limit fluid loss by maintaining fluid levels
• Match intake closely to losses <2% BW
• Maintenance of plasma vol. will maximise endurance
• Minimise gastric distress
• Practise drinking during training

Question 22

What are the ways to have optimal rehydration after exercise? (5)

Answer 22

• High sodium
• Integrated within the diet (protein/glycogen resynthesis)
• Never only water
• 150% fluid losses
• Caffeine during post exercise has more potent diuretic effect