Diet and nutrition Flashcards
What are the 7 classes of food
- Carbohydrates
- Fats
- Proteins
- Vitamins
- Minerals
- Fibre
- Water
What are the two types of carbohydrates
Simple and complex
What are simple carbohydrates
Found in fruits and are more easily digested by the body. Also found in processed foods and anything with refined sugar added.
What are complex carbohydrates
Found in nearly all plant based food and takes longer for the body to digest such as bread, pasta, rice and vegetables
How are carbohydrates digested and stored
They are digested and converted into glucose which enters the blood stream. This is stored at the muscle and liver as glycogen but the stores are only limited.
What is the glycaemic index
Rank of carbohydrates according to their effect on blood glucose levels
What does a lower glycaemic index mean
Cause a slower, sustained release of glucose to the blood so the glucose levels are maintained for longer. Should be eaten 3-4 hours before excersise
What does a higher glycaemic index mean
Cause a rapid, short rise in blood glucose but will be short lived. Should be eaten 1-2 hours before exercise
What are saturated fats
Fats that can be found in both sweet and savoury foods but that come from animal sources.
It can lead to:
-Weight gain
-Poor stamina
-Poor flexibility
-Coronary heart disease
-Diabetes
-High blood pressure
-Body can overheat
What is LDL
Low density lipoproteins - Transport cholesterol in the blood to tissues and are classed as bad cholesterol since they are linked to an increased risk of heart disease
What is HDL
High density lipoprotein - Transport excess cholesterol in the blood back to the liver where it is broken down. They are classified as ‘good’ cholesterol as they lower risk of heart disease
What are trans fats
A type of unsaturated fat that can be found in meat and dairy products and mostly made from hydrogenation. So most are oils leading to high cholesterol
What are unsaturated fats
Fats that are ‘good’ and are a major source of energy for low intensity aerobic work. They also carry fat soluble vitamins such as A, D, E and K
What are proteins
Made up of amino acids for muscle strength and repair to make enzymes, hormones and haemoglobin. They are a minor source of energy mostly used by power atheletes
Sources of vitamin B
Eggs, liver, cereals
Function of vitamin B1 and 2
Break down and release energy from food
Function of vitamin B6
Helps to use and store energy form protein and carbs. Helps form haemoglobin
Function of vitamin B 12
Makes red blood cells, helps to release energy from food
Which vitamins are fat soluble
A, D, E and K
Which vitamins are water soluble
B and C vitamins
Sources of vitamin C
Green veg and fruit
Function of vitamin C
Protects cells, keeps them healthy, maintains bones, teeth, gums and ligaments - injury prevention
Source of vitamin D
By the body under the skin when exposed to sunlight or in a small amount from oily fish and dairy
Function of vitamin D
Helps absorb calcium, keeps bones and teeth healthy - injury prevention
What are the function of minerals
To assist bodily functions such as facilitating transmission of nerve impulses and enable effective muscle contractions
What are the three minerals
Calcium, sodium and iron
What is calciums function
Strong bones and teeth
Efficent nerve and muscle function
What is sodiums function
Regulate fluid levels
Increases risk of stroke or heart attack as too much means a high blood pressure
What is irons function
Forms haemoglobin in red blood cells
Helps to transport oxygen
Lack of it = anemia
What is fibre’s function
Slows down the time it takes the body to breaks down food and provides a slower more sustained release of energy. Helps to prevent constipation and assists digestion
What are the sources of fibre
Pasta
Nuts
Seeds
How much of a persons body weight is water
60%
What does water do
Transports nutrients, hormones and waste products. Helps to regulate body temperature
What is the consequences of dehydration
- Blood viscosity increases
- Reduced sweating to prevent water loss = higher core temp
- Muscle fatigue and headaches
- Reduction in the exchange of waste products
- Increased hr and lower cardiac output
- Decreased performance, reaction time and descision making
What do sports drinks do
Boost glucose levels before competition
Why are supplements used
To enhance sporting performance
What is glycogen loading
As the bodies preferred fuel for endurance events is muscle glycogen but this can become depleted.
Resulting in fatigue and inability to maintain duration and intensity of training
So 6 days before a competition a performer eats a diet high in protein for three days, exercising with high intensity to burn off carb stores.
Then three days of high carbs and light training increasing glycogen stores by two times.
What is creatine monohydrate
Increases the amount of phosphocreatine in muscles used to fuel the ATP-PC system.
Provides energy
Can also help improve recovery times
Use during explosive events
Advantages of glycogen loading
- Increased glycogen storage
- Increased glycogen stores in the muscle
- Delays fatigue
- Increases endurance capacity
Disadvantages of glycogen loading
Carb loading phase:
- Water retention
- Heavy legs
- Affects digestion
- Weight increase
Depletion phase:
- Irritability
- Alter training programme as lack of energy
Advantages of creatine monohydrate
- Provides ATP
- Replenishes phosphocreatine stores
- Allows ATP-PC system to last longer
- Improves muscle mass
Negative effects of creatine monohydrate
- Side effects: muscle cramps, diarrhoea, water retention, bloating, vomiting
- Hinders aerobic performance
- Mixed evidence of benefits
What is sodium bicarbonate
Is an antiacid increasing buffering capacity of blood neutralising neg effects of lactic acid and H+ ions produced in high intensity work.
Reduces acidity in muscle cells to delay fatigue so performers can carry on high intensity work for longer
Used for athletes with lactic acid in system. E.g rowing, 400m run, 100-400 swim
Advantages of sodium bicarbonate
Reduces acidity in muscles
Delays fatigue
Increases blood buffering capacity
Negative effects of sodium bicarbonate
Side effects:
Vomiting, pain, cramping, diarrhoea, bloating
What is caffine
A stimulant increasing awareness.
Improves fatty acid mobalisation in body - sparing glycogen stores.
Used by endurance athletes as fats are preferred
Positives of caffeine
- Increased mental alertness
- Reduces fatigue
- Allows fats as energy/delays glycogen
- Improved reaction time
- Benefit aerobic performance
Negative of caffeine
- Loss of fine control
- Against rules of most sports in quantities
- Side effects: dehydration, insomnia, muscle cramps, stomach cramps vomiting, irregular heartbeat, diarrhoea
