The effects of acute/ Short term exercise on the respiratory system

1. The effects of acute/ Short term exercise on the respiratory system Respiratory response: increase in breathing rate (neural and chemical control); increased tidal volume.

2. Short Term - The mechanics of breathing • When we start to exercise, such as during a warm up the mechanics of breathing alter considerably • This can help to explain how we breathe in faster and deeper during exercise, and therefore help you to answer part of the first two questions. • This increases the amount of air that reaches the alveoli in the lungs.

3. Mechanics of breathing - Inspiration • Muscles work harder • The external intercostals and diaphragm in particular flattens with more force • During exercise, • More muscles are involved • The sternocleidomasoid, sclanes and pectoralis major are now involved as well as the diaphragm and external intercostal muscles • This means that the sternum lifts further and faster than it does at rest

4. Mechanics of breathing - Expiration • During exercise • Becomes an active process • Internal intercostal muscles now contract • They pull the rib cage down • More muscles are involved • Rectus abdominus/obliques now contract as well • The diaphragm pushes up harder into the thoracic cage.

5. Changes to lung volume • Give an example based on a football player that is working at maximum intensity • Eg. He has just sprinted flat out to get on to a through ball. • What changes would you expect to see in the different lung volumes from rest to this maximal exertion. • There is an example on the next slide that will help you with this, and allow you to illustrate your answer

6. Respiratory volumes • Inspiratory Reserve Volume • The amount of space that is available to draw in more air • Eg; Breathe in normally, then breathe in more. This extra capacity is your IRV • Expiratory Reserve Volume • The amount of space that is available to breathe out, once you have exhaled normally • Eg: Breathe out normally, then force out more air. This is your ERV. • Tidal Volume • The volume of air inspired or expired per breath (Approx 500ml at rest)

7. Respiratory volumes • Residual Volume • Breathe out as much as possible • There is always some air left in your lungs • This is your RV (Approx 1200ml) • Vital Capacity • Breathe in as much as you can, and then force as much air out of your lungs as possible. • This is your IRV+ERV+TV, and is your Vital Capacity • Total Lung Capacity • Take in as much breath as possible • This is your total lung capacity • ERV+IRV+TV+RV (Approx 6000ml)

8. Lung volumes example

9. Short term effects – why does our rate of breathing get faster and deeper • Controls the respiratory muscles that initiate breathing • They are under involuntary neural control • We don’t normally consciously control our breathing rate • Breathing is controlled by the Respiratory control centre • Located in the medulla oblongata • Split into inspiratory and expiratory centres

10. During exercise • Chemeroceptors located in the veins • send information to the RCC • Detect the increased content of Carbon Dioxide in the blood and the decrease in Oxygen • This stimulates the RCC to increase the rate and depth of breathing. A number of things stimulate the Respiratory Control Centre to work harder When our muscles use Oxygen, we produce Carbon Dioxide.

11. Long term effects – Vital Capacity • After 6 weeks of training, your respiratory muscles will become stronger. • This means that you will be able to use your external intercostal muscles and sternocleidomastoid muscles to breathe in deeper • And your internal intercostal muscles, abdominals and obliques to push more air out of the body • This will result in an increase in vital capacity Maximum amount of air that you can produce after you breathe out as hard as you can

12. P1/P2/M1

13. Assessment Ideas… • Leaflet • Information Brochure • Power Point • Spider Diagrams for each system -Remember… If you are going for Merit: you only explain in further detail (using examples, sports and wider reading) the musculoskeletal, CV and Respiratory systems.

14. Some added help, questions for you to answer in your work… • What are the acute effects of exercise on the cardiovascular and respiratory systems • -         What causes these responses? What happens during steady state and maximal exercise • -         What are the acute effects of exercise on the skeletal and muscular systems • -         What causes these responses? What happens during steady state and maximal exercise • -          What are the acute effects of exercise on the energy systems • -         What causes these responses, how do the energy systems work together, What happens during exercise of different intensities and maximal exercise.