Patients will often ask me, “What about exercise, Doc? Can I strain my heart? Can I hurt my heart with too much exercise?”
Most heart health practitioners agree that exercise is fantastic for the heart and in most circumstances, we love to see people exercising. However, there are a couple of scenarios of which you should be aware.
There are two main types of exercise: isotonic and isometric.
Isotonic (iso, being the same, tonic, relating to tone) exercise is where there’s lots of movement, the body moves fluidly, and tension in the muscles is not particularly high. Exercises such as swimming and walking fit into this category.
Isometric (iso, being the same, metric, relating to length) exercise is where the muscles are tight and contract firmly; they do not move fluidly. Lifting heavy weights is a form of isometric exercise.
The heart can be damaged with extreme forms of either.
While isotonic exercise is normally fantastic for most people, competitors such as endurance and other elite athletes can do so much training that their hearts can be damaged. The heart dilates due to the heavy, long-term training regime. This leads to increased cardiac output and increased blood flow back into the heart; thus, over time, the heart is stretched.
The danger with too much isometric exercise is that the body’s arteries can become stressed and/or the heart can thicken and affect the pumping capabilities of the left ventricle, the main pumping chamber of the heart.
It is well accepted that bench pressing and lifting lightweights can increase the body’s blood pressure, dramatically. Repetition upon repetition increase shear stress, the stress that results from blood rushing through the blood vessels. This can lead to wear and tear in the arteries: the arteries to the neck, to the heart, or to the aorta, itself (the main artery on the body). If this happens for too long and too often, the heart thickens, as all muscles to do with training. A thickened heart muscle is called left ventricle hypertrophy (left, the left side of the heart, ventricular, the main pumping chamber of the heart, hyper, increased, trophy, growth or size).
Another potential problem is if one or more of the valves within the heart – the tricuspid, pulmonary, mitral and/or aortic valve – is leaky. Increased pressure means more strain and wear and tear on that valve, with the possible likely outcome being failure of the valve. This also affects the pumping capacity of the heart.
So, while extremes of exercise may not be best for your heart’s health, isotonic exercise is highly recommended along with some sensible isometric exercise to keep central muscles and core muscles stable.
In most cases, sensible exercise (in consultation with your cardiologist or GP) is a fantastic aid to ongoing heart health.
The Carousel would like to thank Dr Warrick Bishop for his contribution.
Dr Warrick Bishop is a practising cardiologist in Hobart, Australia, with a passion for preventing cardiovascular disease. A strong proponent of cardiac CT imaging, he has recently authored the books, Have You Planned Your Heart Attack? and Atrial Fibrillation Explained, and last year founded the Healthy Heart Network to further his reach in helping to prevent heart disease.