Getting old is so insulting. Watching yourself turn to carrion is a crime against humanity. Maybe it is justice for the sins of youth. But in addition to philosophy there is science to try and understand senescence. This week’s New England Journal of Medicine has the report of a project to see what kind of exercise is best for pushing back the frailty of old age in obese people. (1) The answer is both aerobic and resistance exercise together is better than either one alone.
This study, the Lifestyle Intervention Trial in Obese Elderly (LITOE) was conducted from April 2010 through June 2015 at the University of New Mexico School of Medicine and New Mexico Veterans Affairs Health Care System. The subjects were all over 65 years of age. The starting hypothesis of these authors was that in the context of weight loss, resistance exercise (otherwise known as body building) would improve physical function better than aerobic or combined aerobic and resistance exercise together. This point of view comes from the concern that weight loss could worsen frailty by accelerating the age-related decline in muscle mass and bone mass together with the observation that health risks are reduced in this age group in people who are fatter. This project had already reported data showing that combined aerobic and resistance training had decreased, but did not prevent, losses in muscle mass and bone mass induced by weight loss. The changes in bodies caused by aerobic and resistance exercise are distinctly different. Aerobic exercise improves cardiovascular adaptations increasing peak oxygen consumption without increasing strength. Resistance exercise improves coordination and strength without improving peak oxygen consumption. These adaptations might actually interfere with each other if done during the same period. These authors thought that if the object was to reverse frailty and prevent muscle and bone loss, then just the resistance kind of training during weight loss by dieting would be best.
The treatment consisted of dieting to lose weight and one or the other or both exercise types. Since the combined group got the same length of time in both exercise regimes they got twice as much exercise overall. The control group didn’t diet, lose weight or do either kind of exercise. The interventions were for 26 weeks. The outcomes measured were overall physical performance abilities, other frailty measures and body composition.
The results stats were as follows: each intervention diet plus exercise plan lost the same 9% total weight, and fat mass 17%. The lean mass decreased less in the combination group 3% and the resistance group, 2%, than in the aerobic group, 5%. The control group didn’t lose anything. The combination group improved physical function and reduced frailty better than either exercise type alone.
So what can we say about these results? Combined exercise is better than either mostly. Exercise will not help you lose weight since twice as much did not cause any more weight loss. But exercise will help you live better and so probably longer and more independently. Even though dieters lost lean body mass, the lean body mass loss was less and what was left worked much better with the exercise, better than the non-dieters-non-exercisers.
What can we maybe say? Don’t do just aerobic exercise if you are dieting because that will cause you to lose more lean body mass without losing more fat mass. Also maybe just more exercise of either kind would work just as well since the combined exercise plan got twice as much overall.
What can’t we say? That dieting in old age will help you live longer or is a good idea.
Getting old is still bad news.
John DiTraglia M.D. is a Pediatrician in Portsmouth. He can be reached by e-mail- firstname.lastname@example.org or phone-354-6605.