Frontiersmen often believed that putting gunpowder on the wound and setting it alight would burn the venom out. More common ways were to cut out the wound (and hopefully the venom), or to drink copious amounts of whiskey to counteract it, but in reality it only sped up the distribution and absorption of the venom.
The blood vessels dilate to increase the "blood traffic" through the lungs to carry more oxygen to the muscle. The lungs work harder (faster respiratory rate) to increase the rate of oxygen/carbon dioxide exchange in the lungs.
Muscular endurance is the capacity of a muscle or combination of tissues to provide repeated reductions on a stand for an extensive duration of time. It is one of the elements of muscular health, along with muscular energy and potential.
