The study found that just six months of heavy lifting results in cognitive improvements in people with mild cognitive impairment (MCI) while significantly slowing neurodegeneration linked with Alzheimer’s disease.
Scientists recruited 100 participants with MCI, split into four groups. Each group was assigned a different management process: strength and computerised cognition training, just strength training, computerised cognition training alone or a “double control condition” of stretching and watching videos.
Over six months, volunteers attended two supervised sessions a week.
Participants were monitored and assessed through MRIs, physical, metabolic and cognitive tests at the start of the study, after six months and again, at the 18-month mark.
“At the end of the six months there was a significant effect on cognition ... for anyone doing resistance exercise,” said senior author Professor Michael Valenzuela, leader of the Regenerative Neuroscience Group at the University of Sydney’s Brain and Mind Centre.
Most interestingly, after the program ended, the “cognitive benefits were preserved” in those who stuck to strength training, even one year after they stopped their supervised routine. The benefits hung around regardless of whether adults kept up their training.
“There seems to be a delayed effect on the brain that is specifically related to that six months of training,” Professor Valenzuela continued.
Cognitive training did see improvements in memory at six months, although, "not as strong” at 18 months. A combination of both cognitive and strength training provided no significant results by the end of the experiment.
“We had been expecting the two things to be better than either, but we didn’t see that,” Professor Valenzuela added.
“Our working hypothesis is that we may have overloaded participants with the double intervention of 45 minutes of strength training and then ... 45 minutes of brain training. My perspective is you probably need to space these things out and have a rest day in between.”
Valenzuela suggests that strength training has certain properties that can't be found in other forms of exercises.
“Exercise stimulates a whole cocktail of biological changes in the bloodstream,” he explained.
“Strength training specifically promotes anti-inflammatory types of mechanisms in the body ... and it strengthens your bones more specifically than aerobic [but] how you get from lifting a dumbbell to an improvement in the hippocampus is not clear at the moment.”
Turns out moving iron won't just get you a great rig.