Section 4.1: Diet and nutrition Flashcards
What are the 7 classes of food that should be present in everyone’s diet?
- carbohydrates
- fats
- protein
- vitamins
- minerals
- fibre
- water
What are the 2 types of carbohydrates?
- simple carbs
- complex carbs
Where are simple carbohydrates found?
in fruits, processed foods and anything with refined sugar in and are easily digested
Where are complex carbohydrates found?
in nearly in plant-based foods, bread, pasta, rice and veg. usually take longer to digest
Name the characteristics of carbohydrates
- principle source of energy used by the body
- main fuel for high intensity or anaerobic exercise
- digested and converted into glucose
- glucose stored in the muscles and liver as glycogen
What is the glycaemic index?
ranks carbs according to their effect on our blood glucose levels
What do food with a high glycaemic index do?
cause a rapid, short rise in blood sugar- should be consumed 1-2 hours before exercise
What is cholesterol?
a type of fat found in the blood
What are LDLs (low-density lipoproteins)?
transport cholesterol in the blood to the tissues and classed as ‘bad’ cholesterol because they are linked to an increase in heart disease
What are HDLs (high-density lipoproteins)?
transport excess cholesterol in the blood back to the liver where it’s broken down. HDLs are considered good cholesterol since they lower the risk of heart disease
What are the different types of fats?
- saturated
- unsaturated
- trans-fats
What are fats used for?
low intensity, aerobic work and a carrier for fat-soluble vitamins A, D, E, and K
What are proteins and their function?
a combination of many amino acids and important for muscle growth, repair, making enzymes, hormones and haemoglobin. minor source of energy, used by power athletes
State good protein sources
meat, fish, eggs and dairy products
What are the 2 types of vitamins?
- fat-soluble vitamins- A, D, E, and K
- water-soluble vitamins- B vitamins and C
Define fat-soluble vitamins
found predominantly fatty foods and animal foods e.g. milk, dairy foods, vegetable oils, eggs, liver and oily fish. stores in the liver and fatty tissues for use at a later date
Define water-soluble vitamins
found in fruit, veg and dairy products. not stored in the body so must be taken daily
What is the source and exercise-related function of vitamin C?
source: green veg and fruit
function: protects cells and keeps them healthy. helps in the maintenance of bones, teeth, gums and connective tissue e.g. ligaments
What is the source and exercise-related function of vitamin D?
source: made by our body when exposed to sunlight. can come from oily fish and dairy produce
function: absorbs calcium which keeps bones and teeth healthy
What is the source and exercise-related function of vitamin B1?
source: yeast, egg, liver, wholegrain bread, nuts, red meat and cereals
function: helps to break down and release energy from food. keeps the nervous system healthy
What is the source and exercise-related function of vitamin B2 and B3?
source: dairy products, liver, veg, eggs, cereal, fruit
function: helps to break down and release energy from food. keeps the skin, eyes and nervous system healthy
What is the source and exercise-related function of vitamin B6?
source: meat, fish, eggs, bread, veg, cereals
function: helps form haemoglobin, helps the body use and store energy from protein and carbohydrates in food
What is the source and exercise-related function of vitamin B12?
source: red meat, dairy products and fish
function: makes red blood cells, keeps nervous system healthy and releases energy from food
What are minerals?
assist the body in bodily functions, tend to be absorbed by the body as ions called electrolytes
What are electrolytes?
salts and minerals found in the blood that can conduct electrical impulses in the body
What’s the exercise-related function of calcium?
needed for strong bones and teeth, also necessary for efficient nerve and muscle function
What is the exercise-related function of sodium?
helps regulate fluid levels in the body
What is the issue with too much sodium?
linked to an increase in blood pressure, which can increase the risk of a stroke or heart attack
What is the exercise-related function of iron?
- helps in the formation of haemoglobin in red blood cells which helps transport oxygen
- lack of iron can lead to aneamia
State good sources of fibre
wholemeal bread and pasta, potatoes, nuts, seeds, fruit, veg and pulses
What is the exercise-related function of fibre?
- slows down the time it takes for the body to break down food
- results in a slower, more sustained release of energy
- dietary fibre causes bulk in the small intestine, helping to prevent constipation and aid digestion
What is the purpose of water?
- transports nutrients, hormones and waste products around the body
- important part in regulating body temperature
- keeps you from overheating
Define dehydration
occurs when the body is losing more fluid than it is taking in
What are the results of dehydration?
- blood viscosity increases, reduces blood flow to muscles and skin
- reduced sweating to prevent water loss, causes increase in core temp
- muscle fatigue and headaches
- reduction in gas exchange of waste products
- increased heart rate resulting in lower cardiac output
- decreased performance/reaction time/decision making
Define glycogen loading
a form of dietary manipulation to increase glycogen stores over and above that which can normally be stored- used by endurance performers
Describe glycogen loading (method)
- 6 days before a competition, performer eats a diet high in protein for 3 days and exercises at high intensity to burn off existing carbohydrate stores
- followed by 3 days of a diet in carbohydrate and light training
State the positive effects of glycogen loading
- increased glycogen storage
- increased glycogen stored in muscles
- delays fatigue
- increases endurance capacity
State the negative effects of glycogen loading
during carbo-loading phase: -water retention, results in bloating -heavy legs -affects digestion -weight increase during depletion: -irritability -can alter training programme through lack of energy
Define creatine
a compound the body can make naturally which supplies energy for muscular contraction, can also be used as a supplement to increase athletic performance
State the positive effects of creatine monohydrate
- aims to provide ATP
- replenishes PC stores
- allows the ATP-PC system to last longer
- improves muscle mass
- improves recovery times
State the negative effects of creatine monohydrate
- possible side effects: muscle cramps, diarrhoea, water retention, bloating, vomiting
- hinders aerobic performance
- mixed evidence to show benefits
Define sodium bicarbonate
a white soluble compound used as an antacid
What is the purpose of sodium bicarbonate?
- increase buffering capacity of the blood
- to neutralise effects of lactic acid and hydrogen ions
- reduces acidity to delay fatigue
State the positive effects of sodium bicarbonate
- reduces acidity in the muscle cells
- delays fatigue
- increases the buffering capacity of the blood
- allows performer to continue to exercise at a high intensity for longer
State the negative effects of sodium bicarbonate
-possible side-effects: vomiting, pain, cramping, diarrhoea, bloating
Define caffeine
a naturally occurring stimulant
State the positive effects of caffeine
- stimulant/increased mental alertness
- improved mobilisation of fatty acids in the body/delays use of glycogen stores
- improves decision making/reaction time
- may benefit aerobic performance/endurance athletes
Why is the glycogen loading method used?
theory is that by totally depleting glycogen stores, they can be increased by up to 2x the original amount and prevent performer hitting the wall
State the negative effects of caffeine
- diuretic so dehydration
- loss of fine control
- against rules of most sports in large quantities
- side-effects: dehydration, insomnia, muscle cramps, stomach cramps, vomiting, irregular heartbeat, diarrhoea
What are good sources of minerals?
meat, fish, eggs, dairy products, cereals, vegetables, fruit and nuts
Give 2 functions of electrolytes
- facilitate transmission of nerve impulses
- enable effective muscle contraction
What does too much saturated fat lead to?
- excessive weight gain which will affect stamina levels
- limit flexibility
- lead to health problems e.g. coronary heart disease, diabetes, high blood levels
- leads to high cholesterol levels
What are trans-fats?
a type of unsaturated that can be found in meat and dairy but most are made from an industrial process that adds hydrogen to liquid vegetable oils (hydrogenation) so that it becomes a solid
Are trans fats ‘good’?
no they lead to an increase in blood cholesterol
