MANY of us nowadays are talking about cardiovascular fitness. To understand how cardiovascular fitness lays the foundation for good health, it helps to know how this amazing system works. I think of the cardiovascular system as the body’s very own package delivery service. Its primary job is to transport oxygen and other nutrients to the rest of the body. The heart serves as a main dispatch terminal where the blood cells go to pick up packages of oxygen which have arrived via the lungs. The heart then pumps the oxygen-filled blood cells out through the main highway the aorta. From there the blood cells are diverted into hundreds of different areas of the body traveling along the blood vessels that vary size (think smaller highways, country roads, city streets).
In some people the blood cells race along like expensive sports cars, delivering their cargo quickly and efficiently before heading back to the heart for the next assignment. But in other people blood cells have problems reaching the destinations. This is the result of traffic congestion in blood vessels that have narrowed by a buildup of cholesterol a naturally occurring substance that is both produced by the liver and common to many foods we eat. The result of this slowdown is that the poor working tissue on the other side of this traffic snarl begins to run out of oxygen and energy. The exhausted tissue begins to slow down, makes more mistakes and anxiously signals its growing distress if the much needed oxygen doesn’t arrive soon.
Initially, you may not be aware of this drama unfolding within your body, but as the situation worsens, you may begin to interpret the body’s distress signals as weakness, shortness of breath, or pain. The heart itself is especially vulnerable to a delay in the arrival of oxygen. About the size of a fist, the heart is the most important muscle in your body. Unlike the majority of our other muscles, it is never able to take even a short break from working. It has it’s own dedicated blood vessels called coronary arteries which keep it supplied with oxygen. If the coronary arteries become clogged with cholesterol and the working heart muscle doesn’t get enough oxygen it is unable to continue functioning properly. This causes chest pain known as angina and often signals an impending heart attack.
Unfortunately for women, recent research suggests that women with cardiovascular disease are less likely to develop the typical symptoms of angina and are more likely to experience vague symptoms like fatigue. For some women this means that by the time cardiovascular disease becomes obvious, it may be too late. Lifestyle choices like smoking, eating high-fat diets and avoiding exercise are often to blame. The simple choices you make everyday like taking the stairs or walking can ultimately play a role in whether or not you die from heart disease.
Cardiovascular exercise
We know without doubt that regular exercise makes the heart stronger and less susceptible to disease. There are several complex scientific theories as to why this is so. Just like any other muscle in the body, the heart muscle adapts to exercise by becoming stronger. Each heartbeat or pulse is simply a result of contraction of the heart muscle. The stronger the muscle is, the stronger the contraction. With each beat of the heart, blood cells are being sent to deliver those packages of oxygen and other nutrients that the body needs. This means the pump itself gets a break and doesn’t have to work quite as hard which will help it to stay strong and healthy longer.
Amazingly while the health benefit of strengthening your heart and reducing your heart rate is enormous, it takes only four to six weeks of regular exercise to achieve. One recent study found that women who simply walked for a total of one hour each week had a lower risk of heart attack. Some of the other benefits of exercise like improved sleep and stress reduction can begin to occur immediately. Of course the reverse is also true. Once you stop exercising you lose most of the benefits you just gained which is why it’s so important to put together an exercise program that you can stick with.
Blood pressure
Blood pressure is the amount of force generated in the arteries as your blood circulates throughout your body. Blood pressure patterns are unique to every individual and can vary significantly throughout the course of a day. In fact your blood pressure can go up or down y several points from minute to minute. Blood pressure is affected by a tremendous number of factors including your level of activity anxiety, caffeine, smoking, weight and heredity. Many medications can also affect your blood pressure including several over the counter cold medicines and weight loss aids, primarily because they contain stimulants.
In the past, doctors thought that exercise helped to lower blood pressure simply by contributing to weight loss. Now we know that a regular exercise program can lower blood pressure independent of weight loss. We still don’t know exactly how this happens. Most likely, it is because exercise suppresses levels of certain hormones (like adrenaline) that elevate blood pressure. Whatever the mechanism, multiple studies have shown that we can easily drop both the systolic and diastolic (top and bottom) components of blood pressure 5 to 10 points with exercise alone. Some of my clients have been successful enough at lowering blood pressure through exercise that they have been able to stop taking antihypertensive medication s saving them money and the risk of medication side effects. And just like a reduction in heart rate, the lowering of blood pressure can be seen in little as four weeks of regular cardiovascular exercise.
I tell some of my busy female clients to find time to exercise. I encourage them to think about how they feel when they are constantly pressured to get things done without enough support or help. That is not a very pleasant feeling but it is precisely the kind of pressure you subject your own heart to when you deny it the benefit provided by exercise.