SPORT NUTRITION

1
SPORT NUTRITION

• Week 12

2
What you need to know

• When and why are CHO and protein important?
• How does a diet need to change for different
  sports?
• What should be eaten before, during and after
  exercise?
• What are the benefits of dietary strategies?
• CHO loading, creatine, caffeine, hydration,
  minerals

3
Carbohydrate (CHO)

• Major fuel source
• Extended, high intensity
• Prolonged, sub-maximal
• Limited capacity to store
• Important to eat before, during and after
  exercise
• The more physical activity the more CHO required
  to be consumed

4
Protein

• Recovery and __________ of body tissue damaged
  during exercise
• Athletes __________ need extra protein in diet
• Normal diet provides sufficient protein

5
Preparing for Competition

• Specific nutritional strategies will help the
  athlete to reach optimal performance
• The athlete needs to avoid nutrition related
  fatigue
• Depletion of __________
• Hypoglycemia (low blood glucose)
• _____________
• Low blood sodium levels

6
Short Duration Sports

• Glycogen depletion does not normally occur
• Little need to increase __________ intake
• Important to restore glycogen levels in __________

7
Team Sports

• Slight increase in CHO intake in 24-36 hours
  before competition can be beneficial

8
Prolonged, Sub-Maximal Events

• Examples
• Increasing CHO intake is important to increase
  glycogen stores
• Should be done 36-72 hours before competition

9
The Pre-Event Meal

• Goals of a pre-event meal
• Finish topping up glycogen stores
• Top up fluid levels
• Prevent hunger
• Timing
• __________ hours before event

10
The Pre-Event Meal

• What to eat
• __________ GI foods
• Why?
• Low in __________
• Fluid
• 300-400ml prior to event

11
During Exercise

• Events lt60 mins
• No intake needed, stored CHO and fat is adequate
• Team sports 60-90 mins
• CHO intake helps maintain blood glucose levels
• Endurance events gt90 mins
• Very important 500-1000ml of sports drink per
  hour
• Ultra endurance events gt4 hrs
• Solid food high in CHO
• Small amounts of fat and protein

12
Recovery

• Restore __________ and liver glycogen levels
  quickly
• High GI foods within __________ mins of activity

13
Dietary Strategies

• Carbohydrate loading
• Creatine supplementation
• Caffeine
• Hydration considerations
• Minerals

14
Carbohydrate Loading

• Benefit for athletes exercising for 90 mins
• Increases muscle glycogen levels
• Exercise at optimal pace for longer
• Exercise tapers off and carbohydrates are
  increased
• Prolongs CHO as main fuel and delays reliance on
  fats
• May increase in __________ due to extra muscle
  glycogen and water

15
Creatine Supplementation

• Hope to increase power, strength and anaerobic
  performances
• Powder ingested daily for 5-7 days
• Increase in rate of PC resynthesis during
  recovery between bouts of high intensity activity
• Eg interval sprint training
• Better able to use __________ system to provide
  energy before using lactic acid system

16
Creatine Supplementation

• Possible side effects
• Weight gain due to increase in water retention
• Muscle cramps, dehydration
• Seizures, diarrhoea, anxiety
• Only to be considered after consulting a
  dietitian or nutrionist

17
Caffeine

• Benefits
• Glycogen sparing for endurance athletes
• Stimulates CNS, which can alter perception of
  fatigue and effort
• Stimulates release and action of adrenaline
• Diuretic (promotes fluid loss)
• Who would use it?

18
Caffeine

• Side effects
• Diuretic fluid loss dehydration and impact on
  temperature regulation
• Insomnia
• Elevated blood pressure
• Where from?
• Doping controls?
• Yes, allows normal social consumption

19
Hydration Considerations

• Water alone is not the most efficient way to
  rehydrate
• It causes bloating, reduces thirst, increase
  urine output
• Fluid lost when exercising contains mineral salts
  (__________) that need to be replaced
• Sports drinks are used because they contain
  electrolytes and carbohydrates

20
Hydration Considerations

• Hypotonic
• Low electrolytes and CHO levels
• Absorbed quickly
• Suitable for athletes who need fluid, without CHO
• Isotonic
• Similar amounts of electrolytes and CHO that the
  body requires
• Absorbed quickly
• Preferred by athlete for refuelling and
  rehydrating
• Hypertonic
• Very concentrated with CHO
• Slower absorption
• Usually after exercise to replace glycogen

21
Minerals

• Often minerals supplements are taken
• Iron, calcium, magnesium, potassium, sodium,
  zinc, phosphorus
• However, a healthy balanced diet contains enough
  minerals
• Eg Iron
• Increases oxygen carrying capacity of RBC
• Hence, improved __________ capacity

22
Activities

• Read p.117-118 and complete activity 9 (p.119)
• Go to http//www.ausport.gov.au/ais/nutrition
• Read tennis fact sheet
• Complete review questions (p.355)
• 3, 4, 6, 7, 8, 9, 10