The primary function of blood clotting is to stop bleeding from cuts in viens and arteries. The first stage in the life cycle of a clot comes when flowing blood makes contact with certain substances in your skin or blood vessel walls. The blood then signals that there is an emergency. Blood platelets bond to the lining of the break and activate chemicals that attract more platelets and other cells. One can consider the initial blood platelets to arrive at the cut as first responders. While they stick to the edge of the damaged area they also bond to each other. They additionally change shape to help form a plug that fills in the broken area which eventually stops the bleeding.
This is the transition into the second stage of a clot. Another layer of protection is formed by clotting factors which are proteins that signal to each other causing a rapid chain reaction. This creates a dissolved solid in your blood consisting of long chains of fabrin. These strands get tangled up with the initial platelets which creates a netting that traps even more particles which creates a more durable clot. Additionals proteins then offset clotting factors which is the circulatgory systems way of declaring the clot is finished.
Finally, in stage three the skin begins to heal over time which decreases the need for the clot. The fibrin strands dissolve and your blood takes back the initial platelets and additional components of the clot.
Unfortunately this cycle can happen in areas of the blood system where the clot is not needed. These are in areas where poor circulation occurs. If blood is stagnant it will begin this process primarily in the legs in a condition known as DVT (deep vein thrombosis). A clot can build up in a vein causing serious swelling in superficial veins as well. These two clots can cause serious pain in swelling with DVT being for more serious as it can lead to a clot breaking off and traveling to the lungs or brain.
These conditions should be taken into consideration when taking long trips by auto or air. Periodic movement helps to keep blood from pooling. The reaction to leg muscle movement works with veins to help pump blood in the veins back towards the heart. A good jog is the perfect weapon in fighting blood clots; I know this first hand. Being born with vericose veins has kept me very active throughout my adult life as a way of preventing pain.vb
References
https://www.health.harvard.edu/heart-health/blood-clots-the-good-the-bad-and-the-deadly
