Your heart’s function is to continuously pump blood so all your body cells receive the nutrition needed to maintain life. The good news is that as the heart ages, the changes it goes through are not very great and its capacity to send blood to all your cells is not diminished when you are at rest. However, there are other age changes your heart may not cope with too well.

How the heart adapts
Though aging causes several changes in the heart, these changes are not serious enough to cause an alteration of the amount of blood pumped per minute (cardiac output, or CO) when we are at rest.

Some of the adjustments the heart needs to make to keep pumping blood effectively to your cells include changes in the atria (chambers of the heart) and the myocardium (middle layer of the heart). As a result of these changes, the heart increases its strength as well as the levels of norepinephrine in the blood, a component that stimulates the heart.

An example of the heart adaptability is how it compensates for a decrease in maximum heart rate caused by age: it increases the amount of blood it pumps per beat. This way, the maximum cardiac output, which can be achieved when a person is exercising vigorously, remains essentially unchanged.

Adverse changes the aging heart can’t compensate for
An adverse change in the heart for which there is no compensatory adjustment is an increase in the amount of blood left in the left ventricle after contraction. This blood results in an accumulation of blood in the lungs, known as pulmonary congestion. Pulmonary congestion may cause pulmonary edema, a condition that reduces the ability to breath, causing people to feel out of breath sooner and more intensely when they exercise strenuously.

Another important heart age change involves its declining efficiency. An older heart consumes more oxygen to pump the same amount of blood pumped by a younger heart. This is not important as long as the coronary arteries remain completely normal because these arteries widen and allow blood to flow adequately when the heart needs more oxygen.

However, most people do not have completely normal coronary arteries. In these cases, the decreased efficiency of the heart and the resultant increased demand for oxygen can become serious. In fact, individuals who show even a small decrease of blood flow in the coronary arteries when exercising are very likely to have a heart attack.

In summary, because there are both positive and negative age changes in the normal heart, its ability to adjust the pumping of blood to supply the varying needs of the body remains essentially unchanged. However, the maximum rate of exercise we can perform normally declines with advance age.

Exercise and the aging heart
Elderly individuals who have been involved in vigorous physical activity throughout their lives benefit from such a lifestyle. If this is not your case, here is a list of the many effects you can obtain if you begin or increase physical activity.

Effects of starting or increasing exercise

1.Circulatory system
Increases cardiac output, cardiac efficiency, HDL cholesterol, and HDL/LDL ratios, blood vessel diameters, and muscle capillaries.
Slows decline in heart functioning.
Decreases resting blood pressure, blood pressure during exercise, heartbeat abnormalities.

2.Respiratory system
Increases clearance of mucus and respiratory efficiency.
Slows decline in respiratory functioning and closing of airways.

3.Nervous system
Increases formation of new axon branches to orphaned muscle cells, speed or impulse processing by the central nervous system, balance, short-term memory, sleep, mental abilities (possible).
Decreases risk of falling.

4.Muscle system
Increases stored glycogen, capillary numbers, blood flow, uptake of oxygen from blood, cell thickness, muscle strength, muscle mass, speed of movement, stamina, endurance.
Slows decline in efficiency of movement and increase in recovery time.

5.Skeletal system
Increases ease of movement, range of movement, joint flexibility
Slows bone demineralization
Decreases risk of falling and sustaining fractures.

6.Endocrine system
Increases glucose tolerance and sensitivity to insulin.

Final words
I am sure after reading the list above you will find the motivation to be physically active and you will include it in your list of New Year’s resolutions. Use the remaining days of 2010 to plan the type of physical activity you will enjoy doing most. In the meantime, enjoy the rest of the holiday season because 2010 is coming to an end quite fast.

To your health!

Emilia Klapp, R.D., B.S.

Author's Bio: 

Emilia Klapp has a Bachelor Degree in Nutrition Science and is certified as a Registered Dietitian by the American Dietetic Association. She counsels and teaches patients who have diabetes type 2, high cholesterol, high blood pressure and are overweight. To read her articles and to receive a list of the calories and sodium content in meals at major fast food restaurants visit her at