Why exercise for the over-50s keeps the brain in top shape
STOPPING exercise for just 10 days leads to a reduction in blood flow to the brain in the over-50s.
The Express reports that researchers claimed one of the areas most affected was the hippocampus – the region responsible for learning and memory which shrinks in people suffering from Alzheimer’s disease. Their exercise regimes included at least four hours of high-intensity training each week. On average they were running 36 miles a week – around five miles a day. The team examined cerebral blood flow in healthy, physically fit older adults – aged 50 to 80 – before and after a 10-day period during which they stopped all exercise. Using MRI brain scans, they found a sharp decrease in blood flow to several brain regions, including the hippocampus, after they stopped exercising. The study by the University of Maryland School of Public Health is published in the journal Frontiers of Ageing Neuroscience. Lead author 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 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.”
People in the study had been involved in endurance exercise for the past 15 years and had completed an endurance event recently. 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. These included 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 Alzheimer’s. 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 stop exercising for 10 days, just as you will lose cardiovascular fitness, you will also experience a decrease in blood brain flow.”
(Article source: Express)