Why do people go red in the face after doing activities?

People go red in the face from the extra blood flow throughout their bodies required by the extra exercise. The face has hardly any fat and the blood fills the capilary cells beneath the skin making them red faced. The face has more capillary cells than any other part of the body and if you get even a tiny scratch, the area will bleed profusely. Same for the ears. This is why mothers of small children who get a scratch on these area goes beserk because their child is bleeding so profusely. Its just a natural occurrance. As a former paremedic, I have had to explain this more than a few times to calm mom or dad down.