exercise physiology Flashcards
What GI food should you have before a race and why?
should have a low GI meal prior
- it is digested and absorbed more slowly, resulting in a gradual release of glucose into the blood throughout the duration of the race
Pre event meal (1-4hrs prior): slower release keeps blood glucose levels topped up prior to race
what GI food should be consumed during the race and why?
High GI foods
They are digested and absorbed quickly
-results in a rapid release of glucose into the blood to replenish glycogen stores that have been used during the race
- help with glycogen sparing
what GI foods should be consumed after the competition and why?
High GI foods
they are absorbed quickly
- result in a rapid release of glucose into the blood to replenish glycogen stores that are used during race
- muscles are most responsive
- athletes should consume protein to enhance muscle recovery
- low GI foods eaten as a main meal after event to replenish glycogen
> assists with repletion of muscle and liver glycogen stores in the 24hrs post exercise
What is a balanced diet?
a diet that contains a healthy amount of macronutrients- proteins, CHO and fats as well as essential minerals, vitamins and water
Consuming the correct nutrients ensures the body…
- meets energy demands
- allows tissue growth and repair
- provides energy for metabolic function
what affects the amount of energy consumed each day?
- age of the individual
- sex of the individual
- level of physical activity
- periods of growth
what are the functions of protein?
- growth of muscle tissue
- repair of muscle tissue
- production of rbc, hormones + antibodies
- contribution to ATP production when carbohydrate and fat stores are depleted
how much protein is sufficient for athletes in heavy training?
1.5-2.0g/kg of body mass on a daily basis and wouldn’t require a supplement
How much fats are recommended for a normal diet?
account for ~ 20-30% of a normal diet
What are fats stored as?
stored as triglycerides in muscle cells and broken down into Free Fatty Acids
What are fats?
they are the major energy source during rest (60%) and light to moderate exercise with little input during intense exercise
Why doesnt the body tend to use fats when energy demands are high?
because the body takes a long time to break down fats
are trained athletes better able to break down fats or worse?
better and hence use them as a fuel source at higher intensities leading to glycogen sparing
what happens when someone first ingests
cho?
- first converted to blood glucose leading to a rise in insulin levels
- excess blood glucose converted to glycogen
> glycogen is stored for future use in the muscle and the liver
?80kg person stores ~400g in muscle and 100g in liver
how much energy do CHO yield?
17kj per g
When does CHO supply energy?
- rest
- low to moderate intensity activity
- high intensity exercise
what is the daily recommended dietry intake of CHO for non athletes?
45-55% of total daily caloric intake
~4.2g/kg daily
what is the daily recommended dietry intake of CHO for athletes?
60% total daily caloric intake
~7-8g/kg daily
what is the daily recommended dietry intake of CHO during heavy training?
70% totally daily caloric intake
~ 8-10g/kg daily
what is a glycemic index (GI)?
a ranking of carbohydrates based on their immediate effect on blood glucose levels
measured on a scale from 1-100
examples of low gi foods:
apples, lentils, kidney beans, peanuts, navy beans, sausages
examples of moderate gi foods:
corn, peas, white pasta, sweet potatoes, oranges, oatmeal, green banana
examples of high gi foods:
pure glucose, honey, white bread, white rice, over ripe bananas
what is rebound hypoglycemia?
rapid rise in blood sugar levels causing an overshoot in insulin release