Unit 1: Anatomy and Physiology in Sport Respiratory system and volumes

Kevin Browne

Recap from last lesson Structure of the respiratory system Diffusion of gases

Learning Objectives To describe 5 respiratory volumes

To identify 5 responses to exercise on the respiratory system

Respiratory VolumesTidal VolumeThis is the amount of air breathed in with each breath

Respiratory rateIs how many breathes you take per minute

Minute VolumeIs the volume of air you breath in one minuteVital Capacity

Respiratory VolumesVital CapacityIs the maximum volume of air you can breath in and out during

one breath.

Residual VolumeIs the amount of air left in the lungs after a full exhalation.

Total Lung volumeIs the maximum amount of air that can be present in the lungs at

any moment.

Quick QuizDescribe the following respiratory volumes:

Tidal Volume Residual volume Total lung volume Inspiratory reserve volume Respiratory rate Minute volume Vital capacity Expiratory reserve volume

Answers to quizTidal VolumeThis is the amount of air breathed in with each breath

Residual VolumeIs the amount of air left in the lungs after a full exhalation.

Total Lung volumeIs the maximum amount of air that can be present in the lungs at

any moment.

Inspiratory reserve volumeThis is the amount of space that is available for air to be inhaled.

Answers to quiz Cont…Respiratory rateIs how many breathes you take per minute

Minute VolumeIs the volume of air you breath in one minute

Vital CapacityIs the maximum volume of air you can breath in and out during one

breath.

Expiratory reserve volumeThis is the amount of air that could be exhaled after you have

breathed out

What happens to the respiratory system when we exercise?

BRAINSTROM: Responses to exercise

Increase in respiratory/breathing rate.

Breathing during exerciseDuring exercise the muscle cells use up more oxygen and produce increased amounts of carbon dioxide.

Your lungs and heart have to work harder to supply the extra oxygen and remove the carbon dioxide.

Your breathing rate increases and you breathe more deeply.

Heart rate also increases in order to transport the oxygenated blood to the muscles.

Breathing during exerciseMuscle cell activity increases – more oxygen is used up and levels of CO2 rise.

The brain detects increasing levels of CO2 – a signal is sent to the lungs to increase breathing.

Breathing rate and the volume of air in each breath increase. This means that more gaseous exchange takes place.

The brain also tells the heart to beat faster so that more blood is pumped

to the lungs for gaseous exchange.

More oxygenated blood gets to the muscles and more CO2 is removed.

Breathing changes during exercise

During rest During exercise

Respiratory rate 14 breaths/ minute

32 breaths/ minute

Volume per breath 0.4 litres 2.4 litres

Minute volume ? ?

Look at these statistics for a 16 year-old athlete:

Calculate the athlete’s minute volumes during rest and exercise.

Rest minute volume = 5.6 litresExercise minute volume = 76.8 litres

The respiratory muscles (the diaphragm and intercostals) get stronger, so they can make the chest cavity larger.

This larger chest cavity means more air can be inspired, therefore increasing your vital capacity.

More capillaries form around the alveoli, so more gaseous exchange can take place.

In the long-term, regular exercise strengthens the respiratory system.

Gas exchange can now take place more quickly meaning exercise can be maintained

at a higher intensity for longer.

Summary of ResponsesShort Term Increase in breathing (respiratory) rate Increase in tidal volume Increase in respiratory volume

Long Term Increased strength of intercostal muscles Decrease in breathing rate Increase in tidal volume Increase in vital capacity Decrease in residual volume