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
People who adopt a
sedentary lifestyle
(not much physical
activity) and eat more
calories than they
use, tend to put on
weight
Active people use more
energy and therefore
need more calories
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 Carbohydrates
Simple: Sugars
Sources include chocolate,
cakes, biscuits, fruit, and
vegetables
Complex: Starch
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 sugar
2 = Simple
3 = Protein
4 = Helps keep bones strong
5 = Prevent dehydration
6 = Blood shunting
Homework
Revise Section 1.1.5 in preparation for an
end of unit test