Effect of exercise on breathing rate (LC 2026) (Leaving Cert Biology): Revision Notes

Effect of exercise on breathing rate

Background:

During exercise, carbon dioxide (CO₂) levels in the blood increase. High CO₂ levels signal the brain's medulla oblongata to make you breathe faster and deeper.

Materials needed:

• Stopwatch

Method:

1. Locate your breath by placing your hand over your mouth and feeling the warm air.
2. Count the number of breaths for one minute while at rest.
3. Perform intense exercise, such as running, for 5 minutes.
4. After exercising, count and record the number of breaths for one minute.
5. Rest for 5 minutes, then count the number of breaths for one minute again.
6. Record all results.

Results:

	Before exercise	Immediately after exercise	Period of rest after exercise
Breathes per minute	20	60	20