Exercise vs Neurodegeneration: What Matters The Most?

Spoiler: what matters the most is how it adds up over time. So the best time to start was decades ago, but the next best time to start is now 😉

Exercise is a critical tool in the fight against neurodegeneration. We talked about it in one of earliest articles here at 10almonds: How To Reduce Your Alzheimer’s Risk

A large part of the reason for this is that exercise is good for the heart, and as we often say, “what’s good for your heart is good for your brain”, and this is because the former feeds the latter, with oxygen and nutrients, and also clears away detritus like beta-amyloid (associated with Alzheimer’s) and alpha-synuclein (associated with Parkinson’s).

See also: The Neuroscientist In The Gym: The Exercise That Protects Your Brain

This exercise doesn’t even have to be incredibly vigorous! For a gentler approach, see for example: How To Walk Away From Alzheimer’s

Now, some of the brain benefits of exercise are immediate:

How Your Exercise Today Gives A Brain Boost Tomorrow

…and some are very measurable over a fairly short timeframe:

Daily Activity Levels & The Measurable Difference They Make To Brain Health

But… What about cumulative activity over time? Does what we did on a Tuesday afternoon 10 years ago matter to our brains today? Or to put the question going forwards: will what we do on a Tuesday afternoon today make a difference to our brain 10 years from now?

This question has now been answered; the answer is “yes“, and the reason for the answer is that every bit of exercise we do, no matter how small, does add up over time:

The study

Researchers (Dr. Suhang Song et al.) investigated cumulative activity over time*, and found that people with higher cumulative physical activity showed slower declines in global cognition, memory, and executive function. The participants were 13,450 adults aged 50+ who were cognitively healthy at the start.

*how much time, you wonder? It was a longitudinal study, with an average participation length of 11 years (of course, participation lengths will differ if individuals die or otherwise withdraw from the study before the end). The upper end on participation was 16 years, as you’ll see in the study title.

What’s important about this study is that they found that being physically active over long periods (not just sporadically) was mostly strongly linked to maintaining better cognitive health. and that the more often and longer people stayed active, the stronger the protective effect became—which means that yes, those benefits grew over time.

As for how the exercise was measured: they calculated cumulative physical activity by combining the intensity, frequency, and duration of all activities each person did over time (using metabolic equivalent rates). This way, it was also possible to look at the total amounts of exercise as a single discrete variable, while taking into account that doing the laundry, for example, is not quite so vigorous as playing tennis.

One cannot really do a randomized controlled trial for this sort of thing (e.g. and the control group will merely believe they are doing vigorous exercise, but in fact it is placebo), and it was also not an interventional study, it rather reflected people’s natural tendencies to exercise more or less and/or in different ways, and one thing that was noticed was that even modest changes such as shifting from occasional to weekly vigorous or moderate activity were associated with a noticeably slower rate of decline.

You can read the paper in full, here: Long-term cumulative physical activity associated with less cognitive decline: Evidence from a 16-year cohort study

Want to learn more?

You might like this book that we reviewed a little while back:

Brain Health Action Plan: Simple, Science-Backed Lifestyle Changes that Optimize Cognitive Fitness and Reduce Alzheimer’s Risk – by Dr. Teryn Clarke

Take care!