Carbohydrate And Exercise Flashcards
Role of carbohydrates and exercise?
Primary energy source for moderate to high intensity exercise
What are carbs stored in the body as
Muscle glycogen - fuels muscle contraction
Liver glycogen - helps maintain blood glucose levels
Blood glucose - immediate energy source
Two types of carbohydrates
Simple - quick energy like glucose and fructose
Complex - sustained energy like starches and whole grains
Short term high intensity
Relies on muscle glycogen
Long duration exercise
Begins with glycogen
Switches to fat as glycogen depletes
Specific carbohydrate needs based on exercise type - light
3-5g/kg/day
Specific carb needs based on exercise type - moderate
5-7g/kg/day
Carb needs based on exercise type - high
6-10g/kg/day
Carbohydrate needs based on exercise type - very high
8-12 g/kg/day
Timing of carbs before exercise
1-4g/kg 1-4 hours before
Prevents low blood sugar and maximises glycogen stores
Timing of carbs during exercise
30-60g carbs per hour (sports drinks, gels etc)
Timing of carbs after exercise
1-1.2g/kg/hour for first 4 hours
Aids in glycogen resynthesis, especially important if training again soon
Glycogen depletion and fatigue
Depleted glycogen = early fatigue, decreased performance
Carb loading
Strategy to maximise glycogen stores before endurance events
Typically done over 3-7 days prior to the event with increased carb intake and tapering exercise
Practical carb sources - pre exercise, during and post
Pre - bananas, oatmeal, toast with honey
During - sports drinks, gels, energy chews
Post - chocolate milk, rice, pasta, potatoes with lean protein
