Scientists have recently found out that just 10 days of break from exercise decreases the flow of blood to the brain.
And researchers from from the University of Maryland School of Public Health said one of the areas most affected was the hippocampus.
This region of the brain is responsible for learning and memory and actually shrinks in people suffering from Alzheimer's disease.
The team examined cerebral blood flow in healthy, physically fit older adults (ages 50-80 years) before and after a 10-day period during which they stopped all exercise.
Using MRI brain imaging techniques, they found a significant decrease in blood flow to several brain regions, including the hippocampus, after they stopped exercising.
Lead author of the study published in the journal Frontiers of Ageing Neuroscience, Dr Jerome Carson Smith said: “We know that the hippocampus plays an important role in learning and memory and is one of the first brain regions to shrink in people with Alzheimer's disease.
“In rodents, the hippocampus responds to exercise training by increasing the growth of new blood vessels and new neurons, and in older people, exercise can help protect the hippocampus from shrinking.
“So, it is significant that people who stopped exercising for only 10 days showed a decrease in brain blood flow in brain regions that are important for maintaining brain health.”
The study participants had all been involved in endurance exercise for the last 15 years and had recently completed an endurance event.
Their exercise regimes included at least four hours of high intensity endurance training each week.
On average, they were running 36 miles each week - the equivalent of a 10k run every day.
Dr Smith and colleagues measured the velocity of blood flow in the brain with an MRI scan while they were still following their regular training routine and again after 10 days of no exercise.
They found that resting cerebral blood flow significantly decreased in eight brain regions, including the areas of the left and right hippocampus and several regions known to be part of the brain's “default mode network” - a neural network known to deteriorate quickly with a diagnosis of Alzheimer's disease.
Dr Smith said: “We know that if you are less physically active, you are more likely to have cognitive problems and dementia as you age.
“However, we did not find any evidence that cognitive abilities worsened after stopping exercising for just 10 days.
“But the take home message is simple - if you do stop exercising for 10 days, just as you will quickly lose your cardiovascular fitness, you will also experience a decrease in blood brain flow.”
Dr Smith believes that this could have important implications for brain health in older people.
He highlighted the need for more research to understand how fast these changes occur, what the long term effects could be and how fast they could be reversed when exercise is resumed.
0 comments: