Applied sport and exercise nutrition

Question 1

What are the main considerations for nutrition requirements?

Answer 1

• Fuel during exercise: carbohydrate/ fat/ protein
  
  • Fluid requirements during/ post-exercise
  • Post-exercise recovery: carbohydrate/ protein –> high freq of training, triathlon, multiple training per day = recovery is most important

Question 2

What are some causes of fatigue during prolonged exercise?

explain some examples:

Answer 2

• substrate depletion
• loss of body fluids
• hyperthermia

Fatigue comes down to factors e.g.: liver glycogen and CHO availability (substrates needed for exercise)
- Also depends on the environment, hyperhydration increases body temperature - increasing water intake. Use of cold foods and drinks to moderate body temperature
- Consuming foods that are more efficient in energy production

Question 3

What are the CHO intake recommendations for recovery after exercise?

How well do athletes usually meet their energy requirements?

Answer 3

Recovery recommendations can be quite taxing
- Will rapidly reach daily target
around 1-1.2g/kg/hr

As EE goes up, so does EI.
Athletes are able to match this pretty well in a competitive environment
- Large EI can be a burden for athletes to reach

Question 4

Describe CHO supplementation:

Answer 4

• CHO ingestion before and during exercise has been consistently demonstrated to enhance performance in events lasting >60 minutes
• Strong rational for using CHO intake

Question 5

What are the
- peripheral
- central
effects of CHO supplementation

Answer 5

• Peripheral Effects:
  glycogen sparing - in 2-3hr window is not shown to work for CHO feeding, but does spare liver glycogen
  maintenance of blood glucose - no drop in blood glucose, so can supply the muscle and brain maintenance of CHO oxidation - ability to utilize CHO, so more efficient that using e.g.: fat
• Central Effects: within brain and its effect from CHO usage

Question 6

Why is CHO supplementation <60 mins before exercise advised?

Answer 6

High intensity triggers metabolic response for liver to kick out lots of glucose
- Done by a warm up to increase liver glucose output and prevent hyperglycemia
- Consumption 1hr prior to exercise does not influence exercise performance for exercise up to 1hr, over an hour can display performance benefits. Only benefit is psychological

Question 7

Can you train the gut for CHO supplementation?

Answer 7

yes, CHO given during training to train the gut to absorb more CHO
- High CHO diet cause gut to adapt to use more CHO in the drinks. Gut may be trainable
- Attributed to transporters in the intestine for the gut to take up water
- Glut 4 transporters did not change in response to the guts feeding adaptations

Question 8

What are some considerations in nutritional requirements?

Answer 8

• Main nutritional considerations:
• Energy balance
• Daily protein intake
• Protein timing around training - intake is most important 1.6 g/kg/day. Distributing protein throughout the day could maximise benefits

Question 9

What are 2 factors influencing energy requirements?

Answer 9

• Due to greater body mass
  
  • Need for an individual approach

Question 10

How can injury risk relate to nutritional requirements?

Answer 10

• Injuries cause the need for changing EI as EE is also different. Diet is very important, vit, min, protein are reduced too
• Hydration is very important, fluid intake during exercise can be difficult for the athlete to achieve. Need for an individualised approach, also looking at their electrolyte concentrations.
• Feeding CHO early = better glycogen re synthesis than feeding it later(closer to exercise)

Question 11

How can you promote recovery with nutrition?

Answer 11

• Promoting recovery is paramount for performance
• Need for a balance between athletes requirements and athletes staying healthy(J-shaped relationship)
  Those exercising more are more likely to get ill, could be lack of nutrients or overexercising