May 2, 2011
I just walked three miles in 50 minutes. My heart rate rose to a maximum of 140 and I worked up a sweat despite the cool temperature and the wind. I am working at improving my cardiovascular fitness through sweat equity. What is cardiovascular fitness and what are collaterals?
Cardiovascular fitness refers to your body’s ability to survive a physical challenge. Collaterals are the plexus of arteries formed in response to exercise and they are what keep you safe and healthy.
According to Merriam Webster’s Dictionary, collateral means, “of, relating to, or being collateral used as security.” While their definition refers to the financial world, it is true in the medical world as well. It is all about security: cardiovascular security.
Picture a body builder’s arms. Body builders have a plexus of bulging, interconnecting arteries that resemble a map of the U.S. interstate system. The body creates and maintains those arteries and veins to support the body builder’s muscles and bones. The body builder stresses his muscles repeatedly. His body does not know if he is doing it because he enjoys it or he wants to be buff; it thinks he is trying to climb a tree or mountainside to get to food or away from something that is trying to kill him. His body makes new muscles and blood vessels in order to survive. The plexus of vessels on his arm and his heart are called collaterals. They parallel the main vessels and add blood supply where needed.
So what do collaterals have to do with cardiovascular fitness? There are three major arteries supplying blood to the heart. If one of them becomes clogged, you have a heart attack! The portion of your heart fed by the clogged artery dies. Everyone has heard of cardiac bypass surgery during which the surgeon harvests veins from the patient’s legs and uses them to bypass (go around) the clogged portion of the artery. What you don’t know is that, if you have healthy collaterals, the newly formed plexus of arteries may actually bypass the clogged artery on their own. If they are large vessels, the patient never knows a segment of his main artery was clogged. If they are smaller arteries, they may provide adequate blood supply to keep the patient alive long enough for his cardiologist to stint, insert a sleeve inside the clogged artery, or the surgeon to repair it.
My exercise routine is slowly progressing. I am now up to 3miles a day and nearing my optimum heart rate. Through sweat equity, I hope to raise enough collaterals to secure a healthy future. I strongly recommend you do the same. The life you save may be your own.