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 Volumes Tidal Volume This is the amount of air breathed in with each breath Respiratory rate Is how many breathes you take per minute Minute Volume Is the volume of air you breath in one minute Vital Capacity

Respiratory Volumes Vital Capacity Is the maximum volume of air you can breath in and out during one breath. Residual Volume Is the amount of air left in the lungs after a full exhalation. Total Lung volume Is the maximum amount of air that can be present in the lungs at any moment.

Quick Quiz Describe 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 quiz Tidal Volume This is the amount of air breathed in with each breath Residual Volume Is the amount of air left in the lungs after a full exhalation. Total Lung volume Is the maximum amount of air that can be present in the lungs at any moment. Inspiratory reserve volume This is the amount of space that is available for air to be inhaled.

Answers to quiz Cont… Respiratory rate Is how many breathes you take per minute Minute Volume Is the volume of air you breath in one minute Vital Capacity Is the maximum volume of air you can breath in and out during one breath. Expiratory reserve volume This 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 exercise During 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 exercise Muscle cell activity increases – more oxygen is used up and levels of CO 2 rise. The brain detects increasing levels of CO 2 – 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 CO 2 is removed.

Breathing changes during exercise During restDuring exercise Respiratory rate 14 breaths/ minute 32 breaths/ minute Volume per breath 0.4 litres2.4 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 litres Exercise 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 Responses Short 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