Learning focus
Develop transferable AO3 skills: plan, measure, record, process, interpret and evaluate biological investigations accurately and safely.
Baseline measurement
Allow the subject to rest, then measure pulse or breathing rate over a defined time. A full minute reduces multiplication error, while a shorter interval may be needed immediately after exercise. Use the same counting method throughout.
Exercise protocol
Standardise exercise type, duration and intensity, such as step-ups at a fixed pace. Measure immediately after exercise and at regular recovery intervals. Stop if the subject feels unwell.
Human variation and ethics
Fitness, age, body size, health, caffeine and anxiety influence response. Participation should be voluntary and suitable for the individual. Comparing a subject with their own baseline controls some variation.
Data interpretation
Describe peak change, recovery time and return towards baseline. Do not assume that the person with the highest peak is least fit without considering exercise intensity and measurement quality.
Practical or data skill
Design a safe exercise-and-recovery investigation. Include rest period, fixed exercise, measurement interval, repeated trials and ethical precautions.
Examination tip
State the counting duration and convert to rate per minute correctly.
Review questions and suggested answers
Question 1
Why measure a resting baseline?
Suggested answer
It provides a comparison for the effect of exercise.
Question 2
Name one human variable that affects heart-rate response.
Suggested answer
Fitness, age, health, body size, caffeine or anxiety.
Question 3
Why measure during recovery?
Suggested answer
To determine how quickly the rate returns towards baseline.
