Unit 2 | kis-igcse-pe

HEALTH

The World Health Organisation define health as: 'a complete state of physical, social and mental well-being and not just the absence of disease or illness'
Physical well-being: all body systems work well, free from illness and injury, able to carry out everyday physical tasks
Social well-being: have friendships, have essential human needs (food and shelter), able to mix with others
Mental well-being: able to cope with stress, can control emotions, feel good about yourself
Health and fitness are linked in many ways. You need both to lead a healthy lifestyle. You should eat a balanced diet, take regular exercise and avoid drugs and pollution.

SAFE PRACTICE AND INJURIES

Anyone leading a sports activity (for example a PE teacher) has a responsibility to keep participants safe
They can conduct a risk assessment to make sure the playing area is clear; identify if the weather may cause an issue; consider the age and ability of students; how many adults are needed to supervise
Rules are important in sport to ensure the safety of everyone and referees are needed to ensure the rules are followed
Injuries are a part of playing sport but there are some ways to prevent injuries: wamr-up and cool down; use correct equipment; know the rules and check facilities.
Some injuries that may occur during sport are: winding; cut or graze; blisters; bruises; sprain or strain.
These injuries may be caused in sport by: impact on ground when falling; impact with another person; sudden movement; inadequate protection; no warm-up. Watch the video below to see some serious sports injuries. Warning - not for the faint-hearted!

Injury treatment

To treat an injury like the ones listed above - use the RICE method.

Rest - rest the injured area to prevent further exersion

Ice - apply ice to prevent pain and swelling

Compression - use a bandage to apply compression to limit swelling

Elevation - lift the injured body part

DIET

There are 7 nutrients that the body requires for energy growth and repair of cells.
Carbohydrates (simple and complex) - primary source of energy that is broken down into glucose in the gut. Some glucose is stored as glycogen in the muscles and liver. Food source: pasta, rice and potatoes.
Protein - needed to build cells, make blood and repair muscle and other tissues. Food source: red meat, eggs and fish.
Fats - these are also used for energy; muscles are made of fat and glycogen. Food source: butter, cooking oils and sausages.
Vitamins and minerals - these are needed in small amounts to allow your body to grow and develop (see info box below for more details about these).
Fibre - this helps the body's digestive system and prevents constipation and bowel cancer. Food source: fruit, vegetables and cereals.
Water - around half of your body weight is water. It is vital to keep you hydrated and transport nutrients and waste around the body.

Vitamins:

There are many vitamins that are useful to the body, for example Vitamin D; which is needed for healthy teeth and bones and comes from sunlight. Vitamin C is also useful and comes from fruit such as oranges. This can help the body's immune system.

Minerals:

Iron is a mineral that comes from food such as red meat and fish. Iron helps the body to transport oxygen in the blood. Calcium is another mineral and this can help to keep bones and teeth strong. This can be found in milk and other dairy products

Energy Balance is when a person's daily energy food intake matches their daily energy need. If someone eats too much and doesn't burn the energy through exercise, they will risk becoming obese (because unused energy is stored as fat). What will happen if they don't take in enough energy?

Watch this video below to learn more about the components of a balanced diet.

EXERCISE

Exercise is an important component of a healthy, active lifestyle with physical, social and mental benefits and it works on all of the body systems.

The body uses 2 energy systems when you exercise aerobic and anaerobic.

Aerobic respiration

uses oxygen to release energy (glucose+oxygen>>>energy+carbon dioxide+water)
when aerobic respiration occurs, muscles contract and some energy is used, muscles warm-up, carbon dioxide is excreted by the lungs
exercise such as long-distance running and rowing are examples of aerobic exercise

Anaerobic respiration

occurs without oxygen (glucose>>>energy+lactic acid)
less energy is produced than in aerobic respiration
excess lactic acid causes pain and fatigue
lactic acid can be removed by breathing in more oxygen
exercise such as 100m sprint is anaerobic respiration

When designing an exercise programme, you should consider the Principles of Training to ensure your programme is suitable for you. The principles are specificty, progression, overload and reversibility. Follow this link to read more about each principle.

In addition, you should also consider which Method of Training you wish to use and which is appropriate for your needs. The methods are circuit training, interval training, fartlek training, continuous training, plyometrics, weight and resistance training. Follow this link to read about each method in more detail and follow this link to read about plyometrics training.

Effects of exercise on the body

Note - key words have been written in red, you must learn these definitions...

Circulatory system

Heart rate is the amount of times the heart beats in one minute - this is measured in bpm
When we exercise, our heart rate increases as the demand for oxygen is greater
stroke volume is the volume of blood pumped out of the heart in one contraction
cardiac output is the amount of blood ejected from the heart in one minute
cardiac output = stroke volume x heart rate
When you exercise your heart rate and stroke volume increase. In the long term, if you exercise regularly, your heart will grow bigger (hypertrophy), you will have a lower resting heart rate and your cardiac output will increase
All of this means the heart doesn't have to work as hard, therefore you are healthier

Respiratory System