Cardiac adaptations to exercise
In light of the news about Manny Pacquiao having a cardiac event prior to the Lucas Matthysse fight, I decided to write about the various cardiovascular adaptations that happen when we exercise. These are the changes that happen to your heart when you exercise:
Heart Size
The muscular walls of the heart increase in thickness, particularly in the left ventricle, providing a more powerful contraction. The left ventricle’s internal dimensions increase as a result of increased ventricular filling.
Resting Heart Rate (RHR)
As cardiac output at rest remains constant, the increase in stroke volume (SV) is accompanied by a corresponding decrease in heart rate.
Cardiac Output (Q)
Cardiac output increases significantly during maximal exercise effort due to the increase in SV. This results in greater oxygen supply, waste removal and hence improved endurance performance.
Blood Pressure (BP)
People with blood pressure in the “normal” ranges experience little change in BP at rest or with exercise; however, hypertensive people find that their BP reduces toward normal as they do more exercise. This is due to a reduction in total peripheral resistance within the artery, and improved condition and elasticity of the smooth muscle in the blood vessel walls.
However, it has been noted that about one in every 50,000 participants in sports experience sudden cardiac death. Ninety percent of these participants are male. The evidence is unclear if too much exercise is to blame, as these events can also be caused by stress, genetic factors, excessively caffeinated drinks, heat or underlying undiagnosed conditions. Hence, it is very important, that if you’re participating in intense sport, always seek guidance from a medical professional.
Overall, exercise is and will always be good for your heart, and the risk for any cardiac disorder because of exercise is close to nil. So start training, and get heart healthy today.