Sport Science

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The Sport! Science Faq 

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All Questions are from the publication The Sporting Life unless otherwise indicated.

 

This list was last updated May 15, 1997

 
Click me to find out the answer  Why do my muscles sometimes burn when I'm excercising?

Click me to find out the answer  Why do I feel sore the day after I exercise?

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 What happens to my heart when I exercise?

 When you exercise, your heart has to pump more blood to supply oxygen to your muscles. The volume of blood that your heart pumps in a minute depends on the heart rate (the number of beats per minute) and the stroke volume (the blood volume pumped by each ventricle of your heart with each beat).

When you exercise, your heart beats faster and contracts more forcefully, pushing out more blood and increasing its stroke volume. During vigorous exercise, the return of blood from your veins to your heart increases, causing the ventricles of your heart to fill more fully with blood, stretching them a bit. Like other muscles, the heart contracts more forcefully if it is stretched a little before contraction. So the increase in returning blood also adds to the stoke volume by increasing the volume of blood in each ventricle and by causing the heart to beat more forcefully.

By training aerobically on a regular basis, you gradually increase the volume of blood that your heart can pump in a minute. This change results from an increase in your heart's stroke volume, since the maximum heart rate isn't changed by training.

Click me to find out the answer What is "VO2 max" and how does it measure cardiovascular fitness?
Click me to find out the answer What's the best position for my hands when I swim freestyle?
Click me to find out the answer How high can you jump?
Click me to find out the answer Why do long jumpers "run" several steps in the air after they take off?
Click me to find out the answer How does ice help a sprained ankle or other injury?
Click me to find out the answer How important is my grip on the bat when I'm striking the ball?
Click me to find out the answer  Why does spinning a ball make it curve?
Click me to find out the answer How does Michael Jordan manage to hang in the air for so long when he goes up for a slam dunk?


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