Diet And Nutrition Flashcards
% of carbs/fats/proteins
Carbs 50-60%
Fats 20-30%
Proteins 10-20%
Two types of carbs
Simple carbs- quickly digested and fast energy release
Complex carbs- longer to digest and provide slower release energy
Carbs in the body
Initially converted to glucose and enters blood stream to be used for energy.
Stored as glycogen in muscles and liver.
Glycaemic index
The rate at which glucose(energy) is released into the bloodstream.
2 types of GI
High GI (simple carbs) - provide rapid surge in blood glucose - quick release energy
Low GI (complex carbs) - absorbed slower so blood glucose levels are maintained for longer - more sustained energy.
GI for health
High GI- rapid energy - energy not used stored as fat in adipose tissue. Can Cause diabetes (body intolerant to insulin)
Low GI foods - fuller for longer
GI for performance
Higher GI - fast release good during and after
Low GI- slow release - 3 hours prior and 30 mins after
Both after exercise to replenish glycogen stored
Fats
Provide energy for long duration, low intensity aerobic exercise
3 types of fat
Saturated- too much=weight gain and health problems (CVD, diabetes, high cholesterol)
Unsaturated fats- provides energy for low intensity aerobic exercise.
Trans fats - type of saturated fats in processed food
Two types of cholesterol
LDL- low density lipoprotein- can block arteries and limit blood flow
HDL- high density lipoprotein- removes LDL deposits and takes to liver for disposal.
Fat use/storage in body
Stored in adipose tissue
Transport fat-soluble vitamins A, D, E, K around the body.
Proteins
Promote muscle growth and repair as well as enzyme, hormone and haemoglobin production. Made from amino acids.
About proteins in the body
Minor energy source when glycogen and fat depleted
If eat too much some stored as fat but rest excreted in our urine.
Hydration? pre/during/post competition?
Process of maintaining the balance between water intake and water output.
Pre: 400-600 in 2 hours before
During: 100-150mil every 15-20 minutes if possible
Post: 1 litre of sweat=1 kg of body weight
Signs of dehydration
Shortness of breath Disorientation Headache Nausea Not needing toilet Clammy/flushed skin Feeling hot Lack of energy/ early fatigue
Effects of dehydration on body
Plasma volume reduced(blood viscosity⬆️) = slow down delivery of blood and o2= heart has to work harder = ⬆️CO ⬆️SV ⬆️HR
Less fatty acids transported for energy =⬆️ levels of lactic acid = fast fatigue.
Ability to thermoregulate is impaired.
Energy sources: carbs
Glucose (15-20g in blood), glycogen (350g in muscle)(90-100g in liver)
Fuels lactic acude and aerobic energy systems
When glucogen stores full excess is stored as fat
Energy sources: fats
Free fatty acids (blood), glycerol(blood), triglycerides- main energy source from fats(stored in adipose tissue)
Digested into fatty acids and glycerol.
Fuel usage
ATP-PC system used first 10 seconds
Then glycogen used
Low intensity long duration - mix of fat and carbs
The higher someone’s aerobic fitness the longer they can metabolise fats, sparing glycogen.
Pre comp good
Low GI 3-4 hours before to allow sustained energy
Avoid immediately prior due to slow digestion.
During exercise
High GI maintain blood glucose & muscle glycogen stores
Immediate energy release
Avoid immediately prior because insulin spike can reduce availability of energy for exercise.
Post comp
Promote muscle repair and replenish muscle glycogen stores.
Low and high GI carbs within 30 mins
Include protein to promote muscle repair
Glycogen loading
Manipulation of diet to maximise glycogen stores and be able to work at higher intensity for longer
Dehydration is?
Condition where the body contains an insufficient volume of water for normal functioning
Dehydration occurs when
Prolonged activity without water especially in hot/humid environment.
Prolonged exposure to dry air
Consumption of alcohol caffeine or other diuretics.
Factor affecting fluid loss
Genetics -some swear more
Body size - bigger people swear more
Fitness- fitter people sweat earlier in greater volumes
Environment- sweat more in hot/humid environment
What’s in sports drinks
Carbohydrates- replace lost energy
Electrolytes- sodium, potassium, chloride, calcium, magnesium. Enhance water absorption and muscle function.
Caffeine- can improve endurance performance- become more aware and decreases perception of effort
Isotonic drinks
Similar concentration of carb as in body fluid (4-8%)
Electrolytes to speed up absorption
Before, during or after
Hypotonic drinks
Low levels of carb (⬇️4%)
Good for athletes without large demand of energy
Hypertonic drinks
High levels of carbs (8%⬆️)
Slow absorption
Consumed with other fluids
Post exercise.
Legal supplements
Enhance performance
Reduce recovery time
Limit fatigue
Whey and Casein
Creatine monohydrate
Caffeine
