Diet And Nutrition Flashcards
Atherosclerosis
Where arteries become clogged with fatty substances
Low-Density Lipoproteins (LDL)
These transport cholesterol in the blood to the tissue and are classed as ‘bad’ cholesterol since they are linked to an increased risk of heart disease
High-Density Lipoproteins (HDL)
These transport excess cholesterol in the blood back to to the liver where it is broken and are classed as good cholesterol since they lower the risk of developing heart disease
Simple carbohydrates
- Quickest source of energy
- Easily digested by the body
- Found in fruits as well as processed food and anything with refined sugar
Complex carbohydrates
- Found in nearly all plant-based foods
- Usually take longer to digest
- Found in bread, pasta, rice and veg
Carbohydrates
- Principle source of energy
- Main fuel for high intensity /anaerobic work
- Carbs are digested and converted into glucose and then enters the bloodstream
- Glucose is stored in muscles and liver as glycogen but the stores are limited so regular refuelling is necessary
Saturated Fats
- Found in both sweet and savour foods, but most come from animal source
- Too much leads to weight gain, which will reduce stamina, restrict flexibility and lead to health problems such as coronary heart disease, atherosclerosis, diabetes and high blood pressure
Cholesterol
- Type of fat found in the blood
- Too much saturated fat leads to high cholesterol levels
- Cholesterol is made predominantly in the liver and is carried away by low-density lipoproteins (LDL) and high-density lipoproteins (HDL)
- Too much LDL can lead to fatty deposits in the arteries, which can have a negative effect on blood flow
- HDL on the other hand takes cholesterol away from the parts of the body where it has accumulated to the liver where it’s disposed of
Trans-fats
- Artificial hydrogenated fats found in meat and dairy products
- Most are made from industrial processes that allow them to have a longer shelf life
- Can lead to high levels of blood cholesterol, heart disease and diabetes
What should saturated and trans-fats be replaced with?
Unsaturated fats - major source of energy in the body
What are fats used for?
Fats are used for low intensity, aerobic work such as jogging and cannot be used for high intensity with limited oxygen because they require oxygen to be broken down
Fats also carry fat soluble Vitamins (A,D,E and K)
Proteins
- Combination of mainly chemicals called amino acids
- Important for muscle growth and repair and to make enzymes, hormones and haemoglobin
- Major source of energy used more by power athletes who have a greater need to repair and develop muscle tissue
Vitamins
- Vitamins keep and individual healthy with a good immune system
- This allows a performer to train maximally and recover quickly
Fibre
- Fibre is important during exercise as it can slow down the time it takes the body to break down food, which results in a slower more sustained release of energy
- Dietary fibre causes bulk in the small intestine, helping to prevent constipation and aiding digestion
- Sources of fibre include wholemeal bread and pasta, potatoes, nuts, seeds, fruit, vegetables and pulses
Water
- Makes up to 60% of a persons body weight
- Essential for good health
- Transports nutrients, hormones and waste products around the body
- Main component of many cells playing an important role in body temperature regulation
- Evaporation of sweat helps you to cool down, but this means water is lost during the cooling down process
Glycogen Loading
A form of dietary manipulation to increase glycogen stores over and above that which can normally be stored (super compensation). An increase in water intake will also aid glycogen storage
Glycogen Loading (Method1)
- Six days before, eat high protein diet for three days
- Exercise at a relatively high intensity to burn off any carb stores
- Next three days, high carb diet and some light training
The theory is that by totally depleting glycogen stores they can then be increased by up to two times the original amount (super compensation) and can prevent a performer from “hitting the wall”
Glycogen Loading (Method 2)
- 3 minutes of high intensity exercise to open a “carbo window” the day before
- Replenishing glycogen stores during the first 20 minutes immediately after exercise, this is when the body is most able to restore glycogen
- Carbo window closes after 2 hours
Glycogen Loading (Method 3)
- Non-depletion protocol
- Training intensity reduces the week before competition. Then three days before competition a high carbohydrate diet is followed with light intensity exercise
Positives of Glycogen Loading
- Increases glycogen storage
- Increases glycogen stores in the muscles
- Delays fatigue
- Increases endurance capacity
Negatives of Glycogen Loading
During Carbo-loading
- Water retention which results in bloating
- Heavy legs
- Problems with digestion
- Weight increase
During Depletion
- Irritability
- Need to alter training programme through lack of energy
Creatine Monohydrate
- This is a supplement used to increase the amount of phosphocreatine stored in the muscles . Phosphocreatine is used to fuel ATP-PC system, which provides energy.
- Increasing the amount of creatine in the muscles will allow this energy system to last longer, also helps improve recovery time
- Athletes in explosive, events, such as sprints, jumps and throws are likely to experience the most benefits as they can perform at a higher intensity for longer
Positives of Creatine Monohydrate
- Aims to provide ATP (energy)
- Replenishes PC stores
- Allows the ATP-PC system to last longer
- Improves muscle mass
Negatives of Creatine Monohydrate
- Muscle cramps, diarrhoea, vomiting, bloating
- Hinders aerobic performance
- Mixed evidence to show benefits
Sodium Bicarbonate
- Sodium Bicarbonate is an antacid. It can increase the buffering capacity of blood, so it can neutralise effects of lactic acid and hydrogen ions that are produced in the muscles during high intensity activity
- The concept behind drinking a solution of sodium bicarbonate or ‘soda loading’ is that it reduces the acidity within the muscle cells in order to delay fatigue and allows the performer to continue exercise at a very high intensity for longer
Positives of Sodium Bicarbonate
- Reduces acidity in the muscle cells
- Delays fatigue
- Increases the buffering capacity of blood
Negatives of Sodium Bicarbonate
- Vomiting, Pain, Cramping, diarrhoea, feeling bloated
Buffering
The ability of the blood to compensate for the build up of lactic acid or hydrogen ions to maintain the ph level
Hydrogen ions
- Responsible for the acidity of the blood
Caffeine
- Naturally occurring stimulant, which can increase mental alertness and reduce fatigue. It is also thought to improve the mobilisation of fatty acids in the body, there by sparing muscle glycogen stores
- It is used by endurance performers who predominantly rely on the aerobic system, since fats are the preferred fuel for the low intensity, long endurance exercise
- Found in coffee, tea, cola, chocolate, energy bars
Positives of caffeine
- Stimulant/increases mental alertness
- Reduces effects of fatigue
- Allows fats to be used as energy source / delays use of glycogen stores
- Improves decision making/reaction time
- May benefit aerobic performance/endurance athletes
Negatives of Caffeine
- Loss of fine control
- Against rules of most sports when consumed in large quantities
- Side effects : dehydration, insomnia, muscle cramps, stomach, vomiting
