Movement and Memory: Which One Comes First?

We are used to hearing the message one way round: move more, and your memory will thank you for it. A study published in JAMA Network Open turns that sentence over and asks whether some of it might run the other way — whether the memory changes come first, and the sitting follows.

The study

Researchers used data from the English Longitudinal Study of Ageing, following 2,529 adults aged 50 and over in England for 17 years. Over that time, participants took repeated memory tests: immediate and delayed word recall, plus verbal fluency tasks such as naming as many animals as possible in a minute.

At one point in the study, participants also wore a wrist accelerometer continuously for eight days. That gave the researchers an objective picture of how much of the day was spent moving, sitting, and sleeping, rather than relying on people to estimate it themselves. Light activity here means ordinary movement: walking, housework, pottering about.

What it found

People whose memory scores held up better across those years were, at the end of it, measurably more active in a very undramatic way. They averaged about 14 more minutes of light physical activity per day, and about 12 fewer minutes sitting, than people whose memory had declined faster.

Fourteen minutes sounds like nothing. Across a week it adds up to roughly 1.6 extra hours of light activity. Among participants over 70, the gap was wider still, at around 2.3 hours a week. The difference showed up most clearly in light activity rather than in structured exercise, which makes sense: most people in their seventies and eighties do relatively little vigorous exercise, so the everyday movement is where the variation lives.

The twist: which direction?

Here is what makes this study worth reading rather than filing under "exercise is good for you". The researchers argue that a good part of what we see in studies like this may be reverse causation. In other words, the memory changes may already have been quietly unfolding for years, and the drop in activity is partly a consequence of them, not only a cause.

That is plausible for reasons that have little to do with willpower. Early cognitive changes can make it harder to plan an outing, to start something, or to keep it going. They often arrive alongside social withdrawal, low mood, or reduced confidence in getting about. It may help explain a pattern researchers have noticed for a long time: activity levels often begin to fall years before a dementia diagnosis.

The study author, Mikaela Bloomberg of University College London, was careful about how she framed this. Her point was not that physical activity is unimportant for brain health, but that changes in activity can sometimes be part of the cognitive ageing process itself rather than simply a cause of later problems.

The honest limits

This was an observational study. It can show that memory trajectories and activity levels travel together; it cannot prove that either one causes the other, in either direction. The link is an association.

There are sampling limits too. The people who wore the accelerometers tended to be healthier, wealthier, and more active than the wider population, and were predominantly white, so the findings may not carry over neatly to everyone. And as Bloomberg noted, moving less is far too unspecific to work as a warning sign on its own — pain, illness, low mood, and mobility problems all reduce activity without any cognitive change involved.

What this means for you

The practical reading is reassuring rather than alarming. If your daily movement has quietly shrunk, that is worth noticing and worth talking about with a doctor, alongside anything else that has changed — but it is not a verdict, and a hundred ordinary explanations come before the worrying one.

What is encouraging is the size of the difference involved. Fourteen minutes of light movement is a walk to the shop, a load of washing hung out, ten minutes in the garden. Whatever the direction of the arrow, that is not a fitness regime, and it is available to almost everyone.

Alongside moving a little more, it helps to give your thinking some regular attention too. That is what Treeny is for: short daily exercises for memory, focus, and mental speed, guided by Flo, your coach, who adjusts the difficulty to where you are today. Not a treatment, not a promise — just a steady way to stay in touch with how your mind is doing.

This article is for general information only and is not medical advice. If you are concerned about changes in your memory, your mood, or your ability to get about, please speak to your doctor or another qualified health professional.