Why do blood will acccumulate in legs if we

[TryingToLuvSci]

Good evening everyone,

I wonder why our blood will accumulate in legs if we don't walk or jog after a running competition. [HKALE2006]

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Is it because if we don't walk or jog , the skeletal muscle will not keep contracting and the venous blood will not return to the heard via Vena Cavae in a faster rate, so the blood that supplied skeletal musles during competition > the blood that can return to our heart, and thus, accumulate in legs??
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I don't know if I am correct or is there any ways to think biologically?
Please teach me a bit. Thanks!

 

[DaveC426913]

The cool-down is important for similar reasons as the warm-up. During vigorous exercise the heart is pumping large volumes of blood to the muscles via dilated blood vessels. The motion of the muscles, particularly the legs, helps the blood return to the heart. By decreasing the heart rate slowly, the blood vessels have a chance to decrease their supply to the muscles gradually. If exercise stops abruptly, the heart is still pumping large amounts of blood, which is then not returned efficiently. The heart must pump harder to get proper blood return. This places stress on the heart and, in the presence of underlying heart disease, may cause symptoms. More commonly, the dilated vessels, and gravity, when combined with decreased blood return to the heart, allows blood to pool in the legs decreasing blood flow to the brain with resultant dizziness or fainting.

Swimming easy for 10 to 20 minutes after a race is called an active recovery. Studies have shown that blood lactate levels (responsible for fatigue), will return to resting levels in 30 minutes after active recovery, rather than 60 minutes with passive recovery such as plopping yourself in a deck chair.

http://www.drjessicaseaton.com/Articles/WarmUp.htm"