Maintaining physical fitness with advancing age has numerous benefits. This study is one of many to show that cognitive function is better in fitter older adults. Many distinct mechanisms are likely involved, from the usual suspects, such as improved autophagy throughout the body, a slowing of vascular aging, and improved blood flow to the brain, to indirect links mediated by the effects of exercise on the gut microbiome and its production of metabolites that can increase neurogenesis. Regardless, exercise costs little. Undertaking more of it is a good plan.
All 70- to 77-year-olds in Trondheim were invited to the Generation 100 study in 2012. Those who agreed to participate were randomly assigned to five years of exercise of various kinds. One group would primarily do high intensity intervals, a second group would mainly go for walks or do other exercise with moderate intensity, and the last group would try to follow the activity recommendations of the health authorities to be physically active for at least 150 minutes each week.
"Our results show that organized training follow-up may have given older men, but not older women, better cognitive function and lowered the probability of mild cognitive impairment. But all in all, it seems that the most important thing is that you actually train in a way that increases your fitness, regardless of whether you get organized help to be physically active or not."
In the groups that received follow-up with high-intensity training and training with moderate intensity, respectively, we found somewhat greater loss of brain volume in deep areas of the brain than among those who trained themselves. But we have to emphasize that everyone in the Generation 100 study - regardless of the form of exercise they did - had less brain loss than expected for people in their 70s. The group that trained on their own without organized follow-up had the least shrinkage in the hippocampus and thalamus.
The 70-77-year-old participants on average had the same cognitive abilities after five years as at start-up, and that during the study period they even improved on some of the tests. The results show that being in good shape like the Generation 100 participants were, is important for maintaining good brain function.