1. A healthy, active lifestyle and your respiratory system
Year 10 GCSE PE
A healthy, active lifestyle and your respiratory system

2. Learning Objectives
Do I know the biomechanical aspects of respiration?
Do I know the difference between aerobic and anaerobic respiration? 2

3. Starter On your white boards…
One partner to explain what happens during inspiration. Breathing in (mechanics and the composition of air)
One partner to explain what happens during expiration. Breathing out (mechanics and the composition of air) 3

4. Composition of inspired air
Oxygen 21%
Nitrogen 78%
Carbon Dioxide 0.03% 4

5. From your own knowledge…
What do you think the percentages are for expired air?
Oxygen?
Nitrogen?
Carbon Dioxide? 5

6. Composition of expired air
Oxygen 17%
Nitrogen 78%
Carbon Dioxide 4% 6

7. We need oxygen to release energy
When participating in exercise we need more
The efficiency of the respiratory system in getting oxygen to the body will have a big impact on the level of performance achieved
E.g. ??
Imagine a 1500m runner who could only walk because he could not breathe enough oxygen into his body to provide enough energy to go any faster 7

8. Expiration and Inspiration
The movement of the diaphragm and the ribs helps the movement of air into and out of the lungs.
During inspiration, the lungs expand to hold more air.
The ribs move up and out.
The diaphragm contracts pulling it tight and flat.
During expiration, the lungs slightly deflate.
The ribs can move downwards and inwards.
The diaphragm can relax (move up). 8

9. Ventilation Rate
Definition: The number of times we inspire and expire in one minute.
During exercise the ventilation rate increases:
- an average adult male will inspire and expire between 10 to 14 times a minute at rest
- this can increase to 25 time a minute during heavy exercise 9

10. Gaseous Exchange
Oxygen is exchanged from the air into the blood stream in the alveoli (tiny air sacs).
 Waste carbon dioxide is transferred from the blood back into the air. 10

11. Key Terms
Vital Capacity The maximum amount of air that can be expired after a maximal inspiration
Tidal Volume Movement of air into and out of the lungs in one normal breath 11

12. Aerobic Respiration
Respiration is the release of energy from glucose in the muscles
When the body is at rest this is aerobic respiration
As you exercise you breathe harder and deeper and heart beats faster to get oxygen to the muscles 12

13. energy + water + carbon dioxide
Energy Equation
Glucose + oxygen →
energy + water + carbon dioxide 13

14. Anaerobic Respiration
When exercising very hard, the heart cannot get enough oxygen to the muscles.
Respiration then becomes anaerobic.
Glucose → energy + lactic acid  14

15. Anaerobic Respiration
Anaerobic respiration can only last for a short period of time.
Lactic acid is produced.
The performer will need time to recover before being able to work at this intensity again.
Examples? 15

16. Anaerobic Respiration
During this recovery period will still be breathing heavily even though they are not working hard.
This is so they can repay the oxygen debt they have developed.
Oxygen Debt The amount of oxygen consumed during recovery above ‘normal’ due to a shortfall of oxygen during activity.
The additional oxygen is used to restock oxygen levels in the muscles and help replenish energy store to break down any lactic acid that has formed. 16

17. Homework
Complete the questions 17

18. Plenary Discuss the following questions in your study buddies –
What it the energy equation for aerobic respiration?
What is the energy equation for anaerobic respiration?
What is oxygen debt? 18