"Our study confirms that people who are stronger do indeed tend to have better functioning brains," said study co-author Joseph Firth from NICM Health Research Institute, Western Sydney University, Australia.
‘Stronger people have sharper brains. Maximal handgrip was strongly correlated with both visual memory and reaction time in over one thousand people with psychotic disorders such as schizophrenia.’
Using data from the 475,397 participants from all around Britain, the new study showed that on average, stronger people performed better in brain functioning tests that included reaction speed, logical problem solving, and multiple different tests of memory.
The study, which used UK Biobank data, showed the relationships were consistently strong in both people aged under 55 and those aged over 55. Previous studies had only shown this applies in elderly people.
"We can see there is a clear connection between muscular strength and brain health," Firth, who is also an honorary research fellow at the University of Manchester in Britain, said.
"But really, what we need now, are more studies to test if we can actually make our brains healthier by doing things which make our muscles stronger -- such as weight training," he added.
Previous research by the group has already found that aerobic exercise can improve brain health.
"These sorts of novel interventions, such as weight training, could be particularly beneficial for people with mental health conditions," Firth said.
"Our research has shown that the connections between muscular strength and brain functioning also exist in people experiencing schizophrenia, major depression and bipolar disorder -- all of which can interfere with regular brain functioning," he added.
"This raises the strong possibility that weight training exercises could actually improve both the physical and mental functioning of people with these conditions," he said.