So argues this important piece in Scientific American (sorry, it’s behind a paywall). So far drugs that target Alzheimer’s have been disappointing. Our best evidence suggests that lifestyle interventions (exercise, improvements in diet, and cognitive engagement) really do help.
This interesting piece in The New York Times argues:
When athletes train consistently, recover smartly and get a little lucky, there’s no physiological reason their bodies should fall off a cliff in their 30s.
From following physiology literature and spending time around late-career elite athletes, I was already well aware that old dogs can both learn new tricks and slow the rate at which they lose old ones.
From The Journal of Alzheimer’s Disease, “Midlife Physical Activity and Cognition Later in Life: A Prospective Twin Study.” Here is the abstract:
Background: Physical activity has been associated with a reduced risk of cognitive decline but the nature of this association remains obscure. Objective: To study associations between midlife physical activity and cognition in old age for a prospective cohort of Finnish twins. Methods: Physical activity in the Finnish Twin Cohort was assessed using questionnaire responses collected in 1975 and 1981. After a mean follow-up of 25.1 years, the subjects’ (n = 3050; mean age 74.2; range 66–97) cognition was evaluated with a validated telephone interview. Both participation in vigorous physical activity, and the volume of physical activity, divided into quintiles, were used as predictors of cognitive impairment. Metrics collected by TELE were used to categorize participants as: cognitively impaired, suffering mild cognitive impairment, or cognitively healthy. Results: Participation in vigorous physical activity compared to non-participation for both 1975 and 1981 was associated with a lower risk of cognitive impairment in individual-based analyses (fully adjusted OR 0.50, 95% CI 0.35–0.73). Pairwise analyses yielded similar but statistically non-significant associations. In terms of the volume of physical activity, the most active quintile of individuals (OR 0.69, 95% CI 0.46–1.04) had a reduced risk of cognitive decline compared with the most sedentary quintile in the fully adjusted model although no clear dose-response was found. Conclusion: Vigorous midlife physical activity was associated with less cognitive impairment but without a clear dose-response association between the volume of physical activity and cognition.
Are we fighting thousands of years of evolutionary history and the best interests of our bodies when we sit all day?That question is at the core of a fascinating new study of the daily lives and cardiovascular health of a modern tribe of hunter-gatherers. The findings strongly suggest that we are born to be in motion, with health consequences when we are not
You can read the abstract of the original research here.
I do yoga and the 10,000 steps a day program.
From Dr. Mirkin’s eZine:
Asking people to stand at work, rather than sit, is not good advice because standing-without-moving is no better than sitting, and will make you too tired to exercise vigorously when you are finished working. If you are a vigorous exerciser, standing all day will slow your recovery from your exercise program.
The highly-publicized studies that showed sitting is harmful for exercisers were flawed because they failed to separate casual exercisers from vigorous exercisers. No one has shown that standing up instead of sitting confers any special health benefits, and standing without moving around can cause additional problems such as varicose veins and swollen feet. Contracting muscles circulate extra blood to strengthen your heart and draw sugar from the bloodstream to lower high blood sugar levels. This does not happen when you just stand in one position without moving your muscles
I am not completely convinced, but I think he raises a good point about the failure of the study to consider individual differences in fitness as a confounding variable.
When I was a kid, there were a number of popular books touting the benefits of isometric exercise. It seemed like a great idea, exercise without equipment, sweat, or repetition. As I remember them, the books would feature highly muscled individuals performing the exercises. Now, I realize that these people must have gained their muscular physiques from workouts with weights, but at the time I was quite convinced.
Naturally, I have become suspicious of claims that you can exercise without exertion. But this article by Dr. Mirkin suggests that passive exercise may have benefits for otherwise inactive people:
The exciting new concept is that passive exercise — sitting on a motor-driven stationary bicycle and letting the pedals move the person’s legs for 30 minutes — burns extra calories and lowers blood sugar and insulin levels in inactive people (Med Sci Sprts Ex, Sept, 2016;48(9):1821-1828). Having their legs moved by motor-driven pedals increases insulin sensitivity by lowering blood sugar rises after eating.
“I heard a piece on NPR a week or so ago that the best thing you can do for your brain is to get more exercise!”
While I would shy away from the word “best,” there is little doubt that regular aerobic exercise has substantial cognitive benefits.
Aerobic exercise helps our brains in several ways. First, and, perhaps, foremost, it reduces the risk of cardiovascular disease and vascular dementia.
Second, as one study reported:
“These results suggest that cardiovascular fitness is associated with the sparing of brain tissue in aging
humans. Furthermore, these results suggest a strong biological basis for the role of aerobic fitness in maintaining and enhancing central nervous system health and cognitive functioning in older adults.”
In addition, aerobic exercise has been associated with improved memory and increased size of the brain region known as the hippocampus. The hippocampus is involved in the consolidation of long term memories.
Finally, exercise has been shown to increase levels of brain-derived neurotrophic factor, which, in turn, stimulates neuron growth.
So regular aerobic exercise should be a central part of any memory improvement program. In addition, this research suggests that efforts to cut physical education programs in the schools may be short sighted.