Section 1.1.5

Your personal health and wellbeing

Lesson 13: A balanced diet

Learning Objectives and Outcomes

W.A.L.F.a. Understand the link between

exercise, diet, work and rest, and their influence on personal health and wellbeing

b. Explain the requirements of a balanced diet

c. Explain the importance and uses of macro and micro nutrients, carbohydrates, proteins, fats, vitamins, minerals, water and fibre in maintaining a healthy, active lifestyle

d. Explain the need to consider the timing of dietary intake when performing due to the redistribution of blood flow during exercise

W.I.L..F.• All of you will be able to explain

the requirements of a balanced diet and its impact on performance

• Most of you will be able to explain the requirements of a balanced diet and its impact on performance and be able to answer exam questions with the help of the teacher

• Some of you will be able to explain the requirements of a balanced diet and its impact on performance and be able to answer exam questions independently

A Balanced Diet

= A diet which contains an optimal ration of nutrients

Provides the energy to work, exercise, rest, and repair tissues

Also maintains an energy balance

Calories In = Calories Out

Energy Balance

Active people use more energy and therefore need more calories

People who adopt a sedentary lifestyle (not much physical activity) and eat more calories than they use, tend to put on weight

If you stop exercising it is important to keep a balance between the amount of calories taken in and the amount used up so you neither lose nor gain weight

Factors of a Balanced Diet

There are seven factors of a balanced diet

These factors are split into two categories:

• Macro Nutrients • Micro Nutrients

Macro Nutrients

These form the biggest part of what we eat

• Carbohydrates• Protein

• Fats

Carbohydrates

• Most of our energy should come from carbohydrates

• This type of energy is stored in our muscles and liver as glycogen

• Quickly converted into glucose and provides us with energy

2 Types of CarbohydratesSimple: Sugars Complex: Starch

Sources include chocolate, cakes, biscuits, fruit, and vegetables

Sources include pasta, potatoes, brown rice, wholemeal bread, and bananas

Protein• Important for building and repairing muscle tissue• Can also provide energy when we exercise over

very long periods of time i.e. marathon running• Sources include meat, fish, poultry, nuts, and

eggs

Fats• Although most of our energy should comes from

carbohydrates, fats also provide energy• To burn energy from fat we should exercise over

long periods at low intensity• Sources include milk, cheese, butter, margarine,

fatty meats, chocolate, and cooking oils

Micro Nutrients

Needed in smaller quantities than macro nutrients

• Vitamins• Minerals• Water• Fibre

Vitamins

• Essential but only needed in small amounts• Help our vision, skin, bones, teeth and healing

capabilities• Can be found in foods or some people take

vitamin tablets• Sources include fruit, meat, cereals, nuts, and

vegetable oil

Minerals• All minerals have a particular function• Two of the most important are calcium and iron

Calcium:

•Important in the formation of bones and teeth

•Helps make bones strong

•Important for older people as it helps to maintain bone density

Iron:

•Important in the formation of red blood cells

•Important to haemoglobin and the oxygen carrying capacity of the blood, without iron the blood would not be able to carry oxygen around the body

•Essential for long distance athletes

Water

• Water holds oxygen and is the main component of many cells

• Transports nutrients, waste and hormones around the body

• Essential in the control of body temperature• During exercise, the body sweats, so water needs

to be taken in for replenishment• Prevents dehydration

Fibre• There are two types of fibre:• Insoluble – adds bulk to our food helping it to

keep moving through the digestive system, preventing constipation. Sources include wholegrain cereals and breads

• Soluble – helps to reduce cholesterol, keeping the heart healthy. Sources include fruit and vegetables

Dietary Intake and Performance

• Knowing what to eat is important so you have a balance diet

• It is important to eat at the proper times in relation to when you intend to exercise or compete

• When we eat we need blood to be directed to the digestive system to help to digest the food

• Blood flow is increased by widening the blood vessels whilst blood flow to other areas of the body is reduced by constriction

Blood Shunting• When we exercise or compete blood needs to be

pumped to our working muscles to provide oxygen

• If we eat just before exercise the blood will be pumped to our muscles and so will not be available in the gut for digestion, which may cause stomach cramps

• Therefore, it is important to eat 2 – 3 hours before you intend to exercise so that food will be digested to provide energy and blood will be available to deliver oxygen to the working muscles

Remember

• Eat a light meal high in carbohydrate at least 2 hours before training or competing

• Understand the energy requirements for your sport and know where the energy in your diet comes from

• Remember to drink plenty of water especially if you exercise or take part in sport

• Try to avoid unsaturated fats and limit animal fats as these are high in cholesterol

Question 1

Name both types of carbohydrate (other than simple and complex)

Question 2

What form of carbohydrate is chocolate and cake?

Question 3

Luke is a discuss thrower. For his event he would emphasise one of the

macro nutrients in his diet. Which would it be?

Question 4

Calcium is an important mineral. Give one example of why it is so

important?

Question 5

Why should a marathon runner drink plenty of water during a race

Question 6

When we exercise, blood is sent to the working muscles. This means that less blood is available for digesting

food, which is why we should not eat too close to exercise. What is this

process known as?

Answers

1 = Starch and sugar2 = Simple3 = Protein4 = Helps keep bones strong5 = Prevent dehydration6 = Blood shunting

Homework

Revise Section 1.1.5 in preparation for an end of unit test