EXERCISE increases lifespan by an average of one to four years for people who engage in moderate to difficult exercise routines. Those additional years will be healthy ones because exercise benefits the heart, lungs, bones and muscles. Even moderate exercise has warded off many dreaded diseases.

Walking briskly for three hours -- about half an hour with a day of rest -- per week can reduce your chances of developing many chronic health problems.

Exercise benefits your brain too. Exercise causes the production of the brain's endorphins -- the body's own morphine-like substances -- that promotes a "feel good" effect.

Thus, exercise may alleviate depression and enhance self-image as well as the quality of life. It can promote weight loss. Of course, it is well known that exercise can aid in the prevention of a number of diseases, including heart disease and diabetes.

Exercise can benefit thegene level. A new evidence was presented in an article entitled, "Endurance exercise as a countermeasure for aging", published on Aug 20 in the online journal Diabetes. Researchers concluded that the reduction in insulin sensitivity that often occurred in one's later years might not be an inevitable consequence of aging.
We have assumed all along that we will become increasingly less sensitive to insulin as we age. In fact, there is a notion that "you will eventually become diabetic if you live long enough".

We have believed for a long time that the only way to prevent this condition was by severe calorie restriction. We have seen that underfed animals live longer.

This new study was done by researchers at the world-famous Mayo Clinic College of Medicine in Rochester, Minnesota. They sought to determine whether long-term endurance training could improve lowered insulin sensitivity.

This is a factor in the metabolic syndrome, which is more prevalent with aging and mitochondrial dysfunction, a widespread condition of aging which has been associated with reduction in insulin sensitivity.

Mitochondria are units in cells that produce energy. Simply put, they are the cell's "power plants".

The team enrolled 22 adults aged between 18 and 30 years, and 20 adults between the ages of 59 and 76 years for this study.

Participants were divided into those who reported less than 30 minutes of exercise per day two times weekly, and those who participated in at least one hour of running or cycling per day six days per week over the past four years.

Blood samples were tested for lipids, glucose, and other factors, and dual x-ray absorptiometry was used to measure fat and fat- free mass. Insulin sensitivity, whole-body peak oxygen uptake, muscle mass, mitochondrial function and SIRT3 expression were also measured.

SIRT3 is a mitochondrial gene of the sirtuin family linked with longevity, whose expression has been found to increase with calorie restriction.

Older participants had less muscle mass, greater adiposity (stored fat) and reduced capacity to use oxygen. However, among those who exercised, oxygen peak was higher and fat was lower than in the age-corresponding sedentary groups.

In the subjects who exercised, insulin sensitivity was greater than the sedentary groups. There was no significant difference between young and old groups.

The age-related decrease in mitochondrial oxidative capacity observed in older individuals was not seen in exercise-trained participants.

Although mitochondrial DNA was higher in those who exercised compared with sedentary participants, it remained greater in younger than in older subjects.

No decline of SIRT3 expression with age was observed among trained adults, although a significant decline was noted in older sedentary participants.

In summary, the authors wrote that "endurance exercise-trained young and older people have substantially higher insulin sensitivity than the sedentary groups, and no differences between young and older people were observed in either sedentary or exercise trained groups".

Second, in contrast, age-related declines were found in various markers of mitochondrial function in the sedentary groups, but these age-related differences were partly, but not completely, abolished in people who practised regular endurance exercise.

Finally, we can see that endurance exercise may exert similar potentially lifespan-enhancing effects as calorie restriction through elevated SIRT3 expression in both young and older adults.

The authors conclude that exercise could have similar effects on lifespan as those observed with calorie restriction in other organisms.

What this means is you are in control of your aging process. Just the simple act of moving your body in a purposeful way could make you not only live longer but also live well in your "golden years".


* Datuk Dr Rajen M. is a pharmacist with a doctorate in holistic medicine. Email him at health@po.jaring.my