We all know that exercise is good for us, but how good is it for the ageing brain? A new review explores how exercise can reduce the risk of dementia and promote healthy brain ageing, suggesting we need to re-think global exercise guidelines.
Short bursts or long bouts?
Queensland Brain Institute researcher and co-author Dr Tara Walker explained that the review’s findings challenge the current World Health Organization guidelines of 150 minutes of moderate-intensity exercise weekly.
“Essentially, the evidence shows that short bursts of high-intensity exercise may provide equal or greater benefits than longer bouts of moderate intensity for healthy ageing,” Dr Walker said.
“Getting your heart rate up to 85% of its maximum is good for protecting your brain against cognitive decline via mechanisms like improved blood flow, reduced inflammation and enhanced neuroplasticity.”
Given that most people do not even get 150 minutes of moderate exercise, the authors argue that changing the health guidelines to small amounts of high-intensity exercise may encourage more people to exercise.
Identifying human research opportunities
The team evaluated the most relevant and influential human and animal studies on exercise and its effect on healthy ageing for The Lancet.
Their review shows that further human studies are required to determine the optimal exercise for healthy ageing.
“We hope this review will help scientists design consistent and controlled human clinical trials that investigate the neuroprotective mechanisms of exercise to help identify the optimal prescription for healthy ageing,” Dr Walker said.
“With a rapidly ageing global population and age being the highest non-modifiable risk factor for dementia, we are facing a significant public health challenge.
“Exercise offers us a low-cost, accessible prevention strategy in the global effort to combat age-related cognitive decline.”
Ongoing research into the neuroprotective mechanisms of exercise
The Queensland Brain Institute and the Norwegian University of Science and Technology team is also collaborating on an ongoing longitudinal exercise study in mice.
Dr Walker’s research is focused on exerkines, proteins and metabolites generated and released by source organs in response to exercise. There is growing evidence that these peripherally released factors play a key role in how exercise affects the brain.
Exerkines may benefit the brain indirectly by directly by enhancing the activities of various pathways. Dr Walker’s team is studying Platelet factor 4 (PF4), which, when released after exercise, results in improved neurogenesis, synaptic plasticity, and learning and memory in aged mice. Read more.
The review Neuroprotective mechanisms of exercise and the importance of fitness for healthy brain ageing was published in The Lancet.
