Longevity Briefs: More Evidence That Exercise Is Always Good, Even If You’re Old And In Poor Health

Longevity briefs provides a short summary of novel research in biology, medicine, or biotechnology that caught the attention of our researchers in Oxford, due to its potential to improve our health, wellbeing, and longevity.

The problem:

We all know at this point that exercise extends lifespan and delays the onset of age-related disease. It doesn’t even take much exercise to have a significant effect, with studies generally suggesting that a mere 30 minutes of moderate exercise a day lowers mortality by 20% or more. Moreover, this holds true even for people who are aged 80 or older. Research even shows that muscle strength, thought of by some as being impossible to build at advanced ages, can in fact significantly increase in 80+ year-olds with proper training (though they will lose that strength faster if training doesn’t continue). So, old people can still benefit from exercise, but what about people who have accrued not one but several age-related diseases? Since these people are quite ill, does physical exercise still extend their lifespans? This study investigates.

The discovery:

Researchers followed 9216 participants with a mean (average) age of 69 and with multimorbidity – two or more chronic health conditions such as high blood pressure, diabetes and dementia. The participants reported their exercise habits at the start of the study and were then followed up for a period of 12 years. Participants were classified into different physical activity level categories based on their participation in various activities and whether those activities were considered vigorous or not (which was informed by accelerometer data from other studies).

Over this followup period, mortality was three times higher among people with the lowest levels of physical activity when compared to those with the highest levels of activity. However, this could have been due to factors besides the physical activity itself, as people who did more exercise were healthier in other ways, such as being more likely to be younger and less likely to be overweight. After using statistical techniques to adjust for these confounders, the effects of exercise were still significant: even moderately low levels of exercise were associated with a 36% reduction in mortality compared to the lowest level of exercise, while the highest level of exercise was associated with a halving of mortality risk compared to the lowest levels.

The implications:

Once again, research fails to find a scenario in which exercise is not good for you. Since this study was observational in nature (researchers observed what happened to participants who were already exercising rather than performing a controlled exercise intervention), there’s a limit to what we can conclude. We can’t be sure that higher levels of physical activity caused all of the reduced mortality, as opposed to other factors that weren’t fully controlled for, or reverse causation (people with worse multimorbidity are less able to exercise).

It’s also worth noting that the results probably reflect – at least in part – the benefits of lifelong exercise habits. If someone is exercising regularly when they are 70, they probably exercised regularly when they were younger and so are in a better position to survive an age-related disease for longer. So the take-home from this study shouldn’t necessarily be that exercising with multimorbidity is beneficial (though this is likely to be the case as well), but that prevention of age-related disease is not the only reason to stay physically fit. Age-related diseases inevitably develop eventually even if you are fit, but are going to be significantly more survivable and less impactful on quality of life.