Many of the people I know are keen sports enthusiasts. For some, exercise is a true passion—dedicated athletes who enjoy challenges and pushing their own limits. Others use it as a way to maintain a healthy weight, or simply because it helps them feel good, recharge their energy, or release adrenaline. Beyond all these almost “miraculous” benefits, physical exercise has the power to improve our overall health—especially cardiovascular health.
But how does it do this? And more importantly, what type of exercise and how much is actually recommended?
Cardiovascular disease worldwide
Diseases affecting the heart and blood vessels are currently the leading cause of death worldwide. While certain genetic factors may predispose some individuals to a higher risk, lifestyle plays a decisive role in their development. Poor diet, physical inactivity and smoking are the main triggers, as they promote high blood pressure, obesity, and disturbances in fat metabolism (dyslipidaemia) and sugar metabolism (insulin resistance, diabetes mellitus). All of these factors damage the health of our blood vessels and heart, which are responsible for transporting oxygen via the bloodstream to every part of the body.
Effects of physical exercise on the cardiovascular system
The cardiovascular benefits of physical exercise have been extensively studied, and the evidence is very strong. Regular exercise has been shown to lower blood pressure, increase insulin sensitivity and improve lipid profiles. It also reduces the likelihood of obesity and helps people quit smoking—key factors involved in the development of cardiovascular disease.
Although these health improvements are well established, the exact mechanisms by which exercise produces these effects are still not fully understood. What we do know is that exercise increases HDL (“good” cholesterol), reduces triglycerides and improves insulin sensitivity, which has a positive impact on metabolic health and helps prevent imbalances in cholesterol, triglyceride and blood glucose levels.
Regular physical exercise also helps prevent the development of atherosclerotic lesions that block blood vessels and increase blood pressure. In fact, these lesions may even regress in people where they are already present. Insulin resistance activates pathways that promote these lesions and the formation of advanced glycation end products, which reduce vascular elasticity, make blood vessels stiffer and contribute to higher blood pressure. Exercise counteracts insulin resistance, indirectly improving vascular health. It also has a direct effect on vascular tone by stimulating the production of vasodilators such as nitric oxide and reducing sympathetic nervous system activity, helping to prevent and reverse vascular stiffness. In addition, exercise reduces inflammation, another key factor in the development of hypertension.
Finally, exercise induces structural adaptations in the heart muscle that improve both systolic (pumping) and diastolic (filling) function, as well as the conduction of electrical impulses that allow the heart to contract rhythmically—helping to prevent abnormalities.
The right dose
The World Health Organization (WHO) recommends 150 minutes of moderate-intensity exercise, 75 minutes of vigorous-intensity exercise, or a combination of both per week to reduce the incidence of cardiovascular disease and other conditions.
You may be wondering what “moderate” or “vigorous” exercise actually means. Intensity is subjective and partly depends on your current fitness level. As a general rule, moderate exercise causes faster breathing but still allows you to speak in full sentences, although with more effort. Vigorous exercise, on the other hand, involves intense exertion that leaves you slightly out of breath. Some studies suggest that vigorous exercise may be particularly beneficial for heart and vascular health, although any increase in physical activity—no matter how small—provides benefits.
Some research indicates that the greatest cardiovascular benefits are achieved with exercise volumes three to four times higher than WHO recommendations. In other words, when it comes to staying active, more often seems better. But is that always the case?
Is there a limit to how much exercise I should do?
There is no doubt that physical exercise improves cardiovascular health and can even increase life expectancy. However, there do appear to be limits.
Several studies suggest that excessive endurance exercise performed over long periods may, in the long term, lead to cardiovascular issues such as increased arterial calcification, greater cardiac muscle fibrosis, heart rhythm disturbances (atrial fibrillation), and a higher risk of sudden cardiac death in individuals with pre-existing heart conditions.
So where is the limit? Science has not yet been able to define a universal threshold, and further research is needed. What the scientific community does agree on is that the cardiovascular risks associated with a sedentary lifestyle far outweigh those of an active lifestyle—even when exercise levels are high.
The key: regular, moderate and personalised exercise
It is essential that your exercise routine is tailored to you, taking into account your age, overall fitness level and any existing cardiovascular conditions. In the latter case, it is crucial to consult your doctor before starting any exercise programme.
If you have been relatively inactive until now, start gradually and increase duration or intensity progressively. This allows your cardiovascular system to adapt safely. For those training at higher levels, a sports medical assessment—including a full cardiac evaluation—is recommended, as it can detect abnormalities that may be asymptomatic but could increase cardiovascular risk when physical demands rise.
