Healthy seniors benefit from resistance training because it repairs their muscle tissue, according to Canadian and American researchers who have found evidence of this mechanism on a molecular level.
Dr. Mark Tarnopolsky, Director of The Neuromuscular and Neurometabolic Clinic at the McMaster University, Hamilton, and Simon Melov of the Buick Institute for Age Research, Novato, California, compared muscle tissue samples taken from 25 healthy, elderly men and women who had engaged in resistance training for a six-month period and similar samples taken from a group of 26 younger people.
"The study demonstrates that it is never too late to start with training, but it also shows that you do not need to spend your entire life on pumping iron in order to benefit from this type of training," Dr. Mark Tarnopolsky tells.
The scientists looked at how the ageing process affected the mitochondrial function, the mechanism that provides the cells with energy. Their study demonstrated that impaired mitochondrial function is involved in the loss of muscle mass and functionality that is normally seen in older people.
Their research found a relation between resistance training and restoration of activity in this area, meaning that the participants reached levels of muscle tissue activity that correspond with levels seen in younger individuals.
Before the study participants embarked on their training regimen they were 59% weaker than the younger controls. After the training period that number had been reduced to 38%.
Four months after the study had ended most of the seniors had stopped training in the gym. Still, they carried on with home exercises using an elastic band. "They managed to preserve their muscle mass and strength," Tarnopolsky said. "This proves that it is never too late to start training."
Although aging research conducted on worms, fruit flies, and mice has shown similar results, Melov was still surprised over the extent of results obtained with the test group.
"The fact that they obtained such significant improvements only serves to prove the value of training, not merely for the sake of general health improvements but also because it slows down the aging process. This lends support to the message that it never too late to start training."
The younger study participants in the control group were between 20 and 35 years of age with an average age of 26 years. The older participants in the test group were all above 65 years of age with an average age of 70. Both groups were compared with regard to diet and training. None of the participants used medicine or had any diseases that affected the mitochondrial function.
The resistance training was carried out twice weekly and lasted for an hour. The different exercises involved the use of standard training equipment and included 30 contractions of every muscle group. Tissue samples were taken from the thigh muscle and the strength test was based on leg extension.