High intensity interval training, which has established heart health benefits, could also help prevent cognitive decline and dementia in older adults.
A University of Queensland study has found that it may increase blood flow in the brain even more effectively than continuous exercise.
It could therefore help protect against the decreased circulation and blood vessel function that occur inevitably with aging, which increases risk of cognitive decline, heart disease and stroke.
Alternating physical activity and rest is best
Interval training involves short bouts of intense physical activity alternating with periods of rest – and it appears that both aspects contribute to the benefits.
“One of the key takeaways from the study,” says researcher Tom Bailey, “was that both the exercise and the rest period were important for increasing brain blood flow in older adults.”
The experiment compared young males with an average age of 25 years and older men aged around 69. They cycled continuously for 10 minutes followed by 10 minutes of rest or for one-minute bouts alternated with one minute’s rest.
Continuous exercise improved cerebral blood flow more than interval training in the younger men but not the older adults, in which both activities had a similar impact on brain blood circulation.
The overall blood flow was higher in both groups during the interval training when measuring the entire activity and rest periods, even though perceived exertion was lower than during the continuous cycling.
This is good news for older adults who struggle to maintain non-stop exercise. It’s also encouraging to note that, contrary to previous suggestions, the interval training did not cause spikes in blood pressure.
“The benefits of exercise on brain function are thought to be caused by the increase in blood flow and shear stress, the frictional force of blood along the lining of the arteries, which occurs during exercise,” Bailey explains, suggesting that the interval training may have increased the shear stress and allowed the blood vessels to adapt to interval training.
He adds that this research will help to optimise exercise programs to improve brain function but points out that the study was short term and more research needs to look at longer term outcomes.
The importance of moving
Disturbingly low levels of activity around the world have sparked the World Health Organisation to recommend that governments take policy action to get people moving more.
They urge all adults – including people over 65 – to do at least two and a half hours of moderate-intensity physical activity each week, for at least 10 minutes at a time, a minimum of 75 minutes of vigorous-intensity aerobic exercise, or a combination of both.
Mobility has numerous health benefits and helps older adults retain better health along with greater independence and quality of life. Aerobic exercise should be interspersed with strength training for optimal benefits to help avoid bone and muscle loss.