Full article is available at the Journal of the American Medical Association's website:

https://jamanetwork.com/journals/jamanetworkopen/fullarticle...

An interesting take-away not mentioned in the BBC write-up is that the researchers found significant effects as early as three years old, suggesting causal factors found in early childhood or a genetic origin. Perhaps sedentary behavior early in life has long-lasting effects for the CNS?

> Lifelong compromised brain health—including poor neurocognitive functioning as early as age 3 years and childhood-to-adulthood decline in cognitive functioning—was associated with slower gait at midlife.