The title of this article is "Why Exercise 2". Its full name is in fact "Why Exercise 2 : the second in a never-ending series".
The latest chapter of this story comes from University of Colorado Boulder and Humboldt State University in a joint study of the effects of running on walking in a group of men and women with an average age of 69 years old. According to the study's findings, running slows the ageing process.
The study shows that people with an average age of 69 who jogged for 30 minutes three times per week expended the same amount of energy when walking as did 20-year-olds. Whereas 69-year-olds who walked rather than ran for exercise expended as much energy while walking as their inactive contemporaries.
“The bottom line is that running keeps you younger, at least in terms of energy efficiency,” said CU-Boulder Associate Professor Rodger Kram of the Department of Integrative Physiology, a co-author on the new study.
The study involved 30 healthy adults, some of whom walked for exercise and some of whom ran for exercise. Participants were tested while walking on a force-measuring treadmill and, for each participant, the amount of oxygen used and carbon dioxide produced was measured. The results were conclusive in that there was a marked distinction between the older runners and the older walkers.
“What we found is that older adults who regularly participate in highly aerobic activities – running in particular – have a lower metabolic cost of walking than older, sedentary adults and also lower than seniors who regularly walk for exercise,” said study leader Justus Ortega, who earned his doctorate at CU-Boulder.
“It’s been known for a long time that as people age their maximum aerobic capacity, or ‘horsepower,’ declines, and that is true for runners as well,” said Ortega. “What’s new here is we found that old runners maintain their fuel economy.”
Having discounted bio-mechanical differences between the two groups, the study's authors have concluded that the difference involved mitochondria inside one's cells. Mitochondria are described by Kram as 'furnaces' inside cells, producing chemical energy - adenosine triphosphate (ADT) - from food to power muscles. They conclude that people who run, or who work out or both have more mitochondria in their cells than walking exercisers. While acknowledging that walking as exercise does have health benefits in reducing heart disease, diabetes, weight-control and depression, it does not act on one's mitochondria levels.
“It was surprising to find that older adults who regularly run for exercise are better walkers than older adults who regularly walk for exercise,” said study co-author Owen Beck. “The take-home message of the study is that consistently running for exercise seems to slow down the aging process and allows older individuals to move more easily, improving their independence and quality of life,” he said.
We'd like to say you heard it here first, but in the spirit of truth we can't do so. However, we can say that once again here is solid scientific evidence to support what has been reported on this site many times, exercise is GOOD FOR YOU AS YOU AGE. And that isn't enough to get you going to the gym or running, then it will be those people who exercise hard the better to do their sport who will also enjoy the benefits when not doing their sport.
The study was published in the online journal PLOS ONE on November 20th.