Investigating the Effects of Physical Activity on Breathing (Cambridge International IGCSE Biology)

Spec point — 11.1.5 · Investigate and describe the effects of physical activity on the rate and depth of breathing

Investigating the effects of physical activity on breathing

• Exercise increases the frequency and depth of breathing
• This can be investigated by counting the breaths taken during 1 minute at rest and measuring average chest expansion over five breaths using a tape measure held around the chest
• Exercise for a set time (at least 3 minutes)
• Immediately after exercising, count the breaths taken in one minute and measure the average chest expansion over five breaths
• Following exercise, the number of breaths per minute will have increased and the chest expansion will also have increased