Materials Required:
Stopwatch or timer (optional, one per pair of students)
Steps Involved:
Start by discussing what heart rate is and how it can be measured by finding the pulse on the wrist or under the neck.
Instruct the children to find their pulse and count the number of beats they feel in 30 seconds.
Once they have counted for 30 seconds, have them double the number to find their resting heart rate.
Explain that this number represents how many times their heart beats in one minute while they are at rest.
Next, have the children do 15 jumping jacks followed by running in place as fast as they can for 15 seconds.
Immediately after the exercise, have them take their pulse again for 30 seconds and then double the number to find their active heart rate.
Discuss the differences between the resting heart rate and the active heart rate. Ask them what happened to their heart rate after exercising and why it increased.
Explain how the heart pumps faster during exercise to supply muscles with more oxygen-rich blood, which is why their heart rate went up.
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