Sitting Too Long Counteracts Cognitive Benefits of Exercise in Older Adults
Cognitive function, particularly for older adults, is influenced by both the amount of time spent exercising and the amount of time spent sedentary, according to a new study.
In order to better understand the relationship between physical activity/fitness and cognitive function later in life, researchers tracked the levels of physical activity in 88 “low-fit” participants between the ages of 60 and 78.
Researchers used accelerometers, attached to the participants during all waking hours, to avoid imprecise reporting of physical activity normally collected in studies of fitness levels.
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They also took images of the participants’ brains, looking for the presence of any white matter lesions, as well as the structural integrity of white matter in the brain as a whole.
As expected, the results showed that the brains of participants who engaged in moderate-to-vigorous physical activity had less white matter lesions than those engaging in less activity.
Of note, the brains of adults who spent the most time sitting, regardless of how much exercise they engaged in at other times, had worse structural integrity compared with those who spent the least time sitting, again, regardless of physical activity.
“This relationship between the integrity of tracts connecting the hippocampus and sedentariness is significant even when we control for age, gender, and aerobic fitness,” researchers concluded.
“It suggests that the physiological effect of sitting too much, even if you still exercise at the end of the day for half an hour, will have a detrimental effect on your brain.”
—Michael Potts
Burzynska AZ, Heyman LC, Voss MW, Wong CN et al. Physical activity and cardiorespiratory fitness are beneficial for white matter in low-fit older adults. PLOS One. 2014 [epub ahead of print] September 17. DOI: 10.1371/journal.pone.0107413
University of Illinois. Study links physical activity in older adults to brain white-matter integrity [press release]. Published September 17, 2014. Accessed September 19, 2014. http://news.illinois.edu/news/14/0917whitematter_Burzynska_Kramer_McAuley.html