A Wonderleaf question
Why does my heart beat faster when I run?
a real page from the book
Your heart beats faster during running because working muscles need extra oxygen and nutrients right away. The heart answers by pumping more blood with each minute, so your legs can keep moving and the used-up air and waste chemistry can be carried off.
The clever part is how quickly your body checks the situation. Sensors in your blood vessels help your brain notice changing oxygen and carbon dioxide levels, then your heartbeat and breathing adjust together, almost like a careful traffic system inside your chest.
Wonder words
- oxygen
- muscles
- pulse
- vessels
Try it out
After ten jumping jacks, feel your pulse, then sit quietly and count again after one minute.
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