The lungs also lose some of their resiliency as we age, starting in our 40s, but this is usually minor. The amount of air the lungs normally hold decreases very little as we age. The ability of the lungs’ lining to fight infection also decreases due to the normal loss of the body’s immunological response to infection, but this doesn’t usually show up until the 70s. Most lung disease and infection are caused by the ravages of years of cigarette smoking.
Of course, the heart also ages, along with the entire vascular system. The blood vessels tend to stiffen with time, and they start to narrow as a result of decades spent eating foods that are high in cholesterol and fat.
In the 40s, the heart starts to lose some of its strength; for example, it takes longer for the heart rate to return to normal after a bout with stress. But the more regularly one exercises, the stronger it will remain. The heart valves also become thicker with age, causing them to leak a little or not to open as much as before, but this usually has no effect on the body. Most people, however, will be able to live well into their 70s and 80s without any heart problems at all, since the effects aging has on the heart become an issue only if there is a serious underlying disease such as a preexisting heart condition or diabetes.
Of course, regular exercise consisting of three 20-minute sessions each week can be quite beneficial, not only for your heart but for your entire body. It has for me, since I have a tendency to be overweight. While I was in medical school, I led a largely sedentary lifestyle, which made it very easy for me to gain weight. After medical school and during my residency, I began to exercise regularly.
Today, at the age of 48, I’m still at it. I exercise for at least one hour three or four times a week; sometimes I even exercise for an hour and a half each day. I run either inside on a treadmill or outside, and I follow it up with a regimen of light weight lifting to maintain my strength. If I can make time, so can you. Of course, you should consult your doctor before you begin any exercise program for a medical evaluation.