You’ve probably heard that exercise is good for your cardiovascular health a thousand times, but how does that actually work?
Scientists are still unsure of the exact ins and outs of some of the biochemical processes, but we looked into the existing research to understand some of the ways that exercise can keep you healthy and prolong your life.
What Do You Actually Need?
The good news is that it doesn’t take much to get the benefits of exercise. Even half an hour a day of moderate activity can dramatically decrease your risk of heart disease. In fact, turning yourself into an Olympic athlete probably isn’t necessary at all. Conditioning has many benefits, of course, but in terms of cardiovascular health the most important distinction is simply sedentary vs. active. In general, the greatest gap in risk of heart disease is that between people who are completely sedentary and people who have a low level of fitness but exercise regularly. The change in cardiovascular mortality rates is comparably small between groups of people who exercise moderately and people who are extremely physically fit and accustomed to vigorous exercise. Even half an hour of brisk walking, swimming, or riding a bike is enough to enjoy the benefits.
In addition, it is never too late to begin experiencing the cardiovascular benefits of exercise. Even people who begin exercising in middle age after being sedentary all their lives see a significant decrease in their risk of heart disease. Overall, people who exercise regularly have a lower risk of developing heart disease, and if they do it is usually later in life and with less severity. Regular exercise also makes recovery from heart disease faster and easier and can help heal arterial wounds caused by atherosclerosis. This tends to be true even in people with other major risk factors for heart disease such as high BMI or a history of smoking.
Many of the processes by which exercise helps your cardiovascular health come from the taxation of your heart during exercise. During movement your heart has to pump blood more quickly to get enough oxygen to your muscles. Over a prolonged time period of consistent exercise, your heart will eventually adapt to this new stressor by getting larger. The increase in heart mass can lower your resting heart rate, which is a benefit because elevated heart rate is a risk factor for cardiac arrest. In addition, the functional remodelling of the heart strengthens it overall. Beneficial changes include a thicker ventricular chamber wall, an improvement in the heart’s ability to contract consistently, and an overall increase in cardiac function. These adaptations can reduce the risk of heart failure and arrhythmia. The increased blood volume needed can also cause the arteries to become more flexible and expand permanently, much as the heart’s mass permanently increases, which reduces blood pressure and makes plaque build-up less likely. This reduces the risk of coronary heart disease and atherosclerosis.
Cholesterol and Insulin
Exercise can also help alter the cholesterol composition of your blood plasma. Although it can lower cholesterol levels overall, its main benefit is to lower the levels of LDL (bad) cholesterol and increase the levels and particle size of HDL (good) cholesterol. An excess of LDL is a major risk factor for heart diseases such as atherosclerosis. HDL, however, can help with some biological processes that contribute to heart health. When HDL particles are enlarged, they can become more efficient and effective.
Another major benefit of exercise is an increase in arterial health, which is closely related to insulin sensitivity and cholesterol. Exercise can increase your sensitivity to insulin and help you regulate your blood sugar levels. Low insulin sensitivity can be associated with an increase in LDL and overall cholesterol levels and a decrease in HDL levels. Insulin irregularities such as those seen in people with diabetes may also make it more difficult for the body to transport cholesterol away from the walls of your arteries, which can contribute to plaque build-up. Plaque build-up constricts the arteries, which leads to high blood pressure and atherosclerosis and increases the risk of needing a coronary bypass surgery.
In addition, while you need some degree of insulin signalling to maintain your heart health, an excess of insulin can be detrimental. Insulin signalling triggers your vascular dilators, chemicals such as nitric oxide which signal for the arteries to expand and the smooth vascular muscles to relax. When insulin resistance is too high, however, it can activate a pathway responsible for cell growth. This pathway produces vasoconstrictors, which signal for the arteries to contract and the smooth vascular muscles to stiffen. These processes result in stiff, narrow arteries, which increases the risk of high blood pressure, atherosclerosis, and other heart diseases.
Improved cardiovascular function also increases your VO2 max, the maximum volume of oxygen that circulates in your blood. Because you need a high volume of oxygen during exercise, it can increase your overall oxygen levels even when you are sedentary as your body adapts to an active lifestyle. High oxygen volume is important because it makes ordinary tasks feel less strenuous and decreases fatigue overall. This is especially important if you have an existing heart disease, as you may feel fatigued more easily or have a lower capacity for exercise.
Exercise is essential to maintaining your cardiovascular health, but there are some slight risks associated with it. If you are a healthy adult, exercise is a fairly low-risk activity. If you have an existing heart condition, you should consult your doctor before beginning a programme, as exercise temporarily raises your heart rate and blood pressure and could be dangerous for you. Prolonged strenuous exercise such as frequently running marathons can also increase your risk of heart problems such as arrhythmia and cardiac arrest due to the strain placed on your cardiovascular system. 40-60 minutes of exercise per day usually has the highest positive impact on your heart health.
The Bottom Line
Exercise is one of the best ways to protect yourself against heart disease or make the symptoms of an existing heart disease less severe. It can help lower your resting heart rate and blood pressure, alter your cholesterol levels, make your arteries stronger and more flexible, and help with oxygen circulation in your blood. Even half an hour a day of moderate exercise is enough to experience a dramatic decrease in your risk of developing a heart disease.
If you have any questions on the above or would like some advice on how we could help you with your fitness goal, don’t hesitate, visit our gym and try one of our personal fitness training sessions.