The link between physical activity and brain health is well established, but is it necessary to achieve the recommended 10,000 steps a day to gain a beneficial effect?
Maybe not, an observational study of middle-aged adults, conducted by the Boston University School of Medicine, suggests.
Researchers measured activity levels in more than 2,300 volunteers wearing a small accelerometer for up to eight days, to measure their energy expenditure and step counts. Magnetic resonance imaging was also used to assess participants’ brain volume in relation to their skull volume.
What they found was that individuals who took at least 7,500 steps per day had larger brain volumes than those averaging fewer than 7,500 steps per day. So spending 10 to 19 minutes per day on moderate physical activity was linked with 0.29% higher brain volume, compared to those averaging less than 10 minutes per day.
Those activity levels are lower than current guidelines of about 21 minutes of activity and at least 10,000 steps per day in order to achieve substantial health benefits.
Importantly, the incremental gains to brain volume associated with those who achieved the 10,000 step a day mark were much smaller.
“There shouldn’t be very much space extra space in the skull that is not filled with brain tissue. If we see lots of extra space then this suggests that the brain may have atrophied or shrunk and is linked to dementia,” study researcher Nicole Spartano told Reuters Health.
JAMA Network Open; online 19 April