Exercise Recovery

Biology: Cambridge International GCSE Supplement, topic 9.2.4

A person's physical fitness affects how quickly their pulse (heart rate) & breathing rate recover (return to normal) after exercise.

Muscle cells use up more energy (released in respiration) during exercise, so they need to respire at a faster rate.
Breathing rate increases to take in more oxygen and to get rid of the carbon dioxide produced by respiration.
The heart pumps faster to circulate oxygenated blood to muscle tissues.
The heart rate and breathing rate of fit people return to normal faster after exercise than those of less fit people. Less lactic acid (from anaerobic respiration) builds up in the muscles of fitter people.

Record someone's pulse (beats per minute) and breathing rate (breaths per minute) while they're sitting down.
Measure their pulse and breathing rate again straight after they have done 4 minutes of intense exercise.
Measure again two minutes later. Have their pulse and breathing rates returned to normal?

Test yourself on Exercise Recovery