Effects of Exercise

the respiratory system

Homework

• We all need our homework out for the first 2 tasks.

Lesson Objectives

• Understand the short term and long term effects exercise has on respiratory system

• Be able to explain what oxygen debt is and why it occurs

• Understand the terms vital capacity, tidal volume, residual volume and lung capacity

Recap

• http://www.youtube.com/watch?v=HiT621PrrO0&feature=related

• http://www.youtube.com/watch?v=HiT621PrrO0&NR=1

Short term effects

• Increased breathing rate • Increased depth of breathing• Increased demand for oxygen• Inreased rate of CO2 removal• Gaseous exchange• Oxygen debt

Effects of training & Competition

• At rest, quiet breathing is sufficient to supply the body with oxygen (O2) & remove carbon dioxide CO2

• During exercise the demand for O2 is increased by the muscles

• Therefore more CO2 is produced & needs removing

• As a result the depth and rate of breathing increases to take in more O2 & remove the extra CO2

Effects of training & Competition

Effects of exercise– Anaerobic exercise can cause the body to build

up an oxygen debt.

– This is due to the body not taking in enough O2 for the work the muscles are doing e.g. 400m sprint

– This O2 debt must be paid back as it is needed to remove the levels of CO2 and lactic acid built up through exercise

Oxygen debtAfter anaerobic activity, oxygen is needed to neutralize the lactic acid. This is called an oxygen debt. It is repaid after exercise.

The oxygen reacts with the lactic acid to form CO2 and water.

Rapid and deep breathing is needed for a short period after high intensity exercise in order to repay the debt.

This also helps to remove the carbon dioxide which accumulates in the blood during intense exercise.

Oxygen Debt

• Oxygen debt is the amount of oxygen consumed during recovery above the amount that ordinarily would have been consumed at rest in the same time.

• Task 1 – Complete booklets

Effects of exercise

• Aerobic respiration provides energy for walking jogging etc.

• When you need energy fast e.g sprinting anaerobic respiration takes over

• But after short time Lactic Acid builds so high causes pain & stops muscles working

Gas exchange at the alveoliThe alveoli are bunches of tiny air sacks inside the lungs.

Each individual sack is called an alveolus.

When you breathe in, they fill with air.

The alveoli are covered in tiny capillaries (blood vessels).

Gases can pass through the thin walls of each alveolus and capillary, and into the blood stream.

Gases can also pass from the blood stream, into the alveolus.

Gas exchange at the alveoli

Measuring breathingTidal volume is the amount you breathe

in and out in one normal breath.

Residual volume is the amount of air left in your lungs after you have breathed out as hard as you can.

Minute volume is the volume of air you breathe in one minute.

Respiratory rate is how many breaths you take per minute.

Vital capacity is the maximum volume of air you can breathe out after breathing in as much as you can.

Multiply togetherTidal volume and respiratory rateThis will give you minute volume!

Measuring respiration• Vital Capacity (VC) is

the maximum amount you can inspire and expire in one breath

• Tidal Volume (TV) is the amount of air inspired & expired in a normal breath

• TV increases with exercise

• VC can increase when improved by training

Tidal

Volume

Residual

Volume

Vital Capacity

Total Lung Volume = Vital Capacity + Residual Volume

• Task 3 – We are going to measure our tidal volume and

vital capacity.– In pairs follow the instructions on the sheet. – We will be feeding back our results to the rest

of the class.

Long term effects

• Stronger diaphragm• Stronger inter costal muscles• Increased amount of capillaries • Increased lung capacity• Increased lung volume• Increased vital capacity

The effects on lung structures

• 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.

• Task 2– Complete booklets

Summary

• Write down a summary of three thing you have learned in today’s lesson

• Write down 1 thing you didn’t quite understand

Homework

• Complete two pages in the booklet– The components of the respiratory system– Mechanics of breathing