The heart is responsible for the circulation of nutrient-rich blood and the removal of wastes from the cells. It also works in conjunction with the lungs to carry oxygen to tissues throughout the body. The heart beats continually and does not depend on direct stimulation from the nerves to function. The heart is considered a muscle and is strengthened or weakened in much the same way as other muscles in the body. The following short video with further explain:
Stimulation: In the cardiac (heart) muscle, the cells that stimulate the muscle to contract are called pacemaker cells. They are located within the muscles and constantly send signals to keep the heart functioning. Because the heart relies on the pacemaker cells for stimulation, it does not need direct input from other nerves. Cardiac muscle cells are controlled by the autonomic nervous system. They are involuntary, which means they function on their own, without the person having to think about making them work. This is why the heart will continue to beat, even when it is removed from the body.
Heart Attack and Disease: Diseases such as arteriosclerosis and atherosclerosis are diseases that cause plaque to build up within the arteries that surround and nourish the heart muscle. As these arteries become blocked, blood flow to the heart muscle is diminished, and the muscle itself begins to deteriorate. This can lead to myocardial infarction, or a heart attack. You can literally add 10 years to your life through good nutrition, keeping a healthy weight, maintaining normal blood pressure, and cholesterol along with not smoking.
One Final Tip: Very simply stated, it is never too late to help your heart out. And by doing so, you can play an active role in extending your life.