Physical exercise is known to be an essential lifestyle choice for anyone who wants to maintain their cognition. It boosts oxygen and nutrient supply to the brain as well as stimulating the release of neurochemicals, such as BDNF, (brain derived neurotrophic factor) which enhances the maintenance of existing neurons as well as stimulating the birth of new brain cells in a process called neurogenesis.
Previous studies have reported that people who exercise regularly, not necessarily with vigorous exercise but with a daily routine of 20-30 minutes of say walking, benefit the most in terms of maintaining memory and thinking skills.
Brain scan studies have shown exercise slows down brain shrinkage, which develops due to loss of neuronal connections. A U.S. study reported that walking for 6 -9 miles per week was associated with helping to maintain memory as well as reducing brain shrinkage. Other studies have shown that regular moderate exercise can reduce a person’s relative risk of dementia or Alzheimer’s disease and that certain forms of exercise such as ballroom dancing are particularly good because they produce cross-training for the brain.
One area of the brain that is associated with learning and memory is called the hippocampus. This brain area typically shows damage early in Alzheimer’s disease. Being able to maintain the size of one’s hippocampus is important as a means of reducing relative risk of cognitive decline.
One study reported in early 2011 showed that walking for 40 minutes three times a week produces an increase in hippocampal volume, significant enough not only to show up on brain scans but translating into one to two years of better cognition by preventing hippocampal volume loss.
In the study, 120 subjects in their mid sixties either walked for 40 minutes three times a week along with a warm up and cool down session while the control group did less aerobic stretching and toning exercises, yoga and resistance training with rubber bands.
After one year follow up brain scans showed that the control group had hippocampal volume loss of 1-2% while the walking group had increased in volume by 2%. Both groups showed improvements in spatial memory but this was more marked in the walking group. The walking group also had higher levels of BDNF the neurochemical associated with enhancing neuronal support and neurogenesis.
None of us can avoid the ageing process. Hippocampal loss is a common finding with ageing. However moderate exercise appears to be able to reverse this trend that could mean a lower risk of memory problems and Alzheimer’s disease in older age.
So what would you choose? A sedentary lifestyle associated with continuing brain shrinkage and hippocampal loss or a lifestyle, which incorporates daily regular exercise to ensure you keep your memory intact and sharper for longer?
I’ve already made my choice. What’s yours?
Erickson, K.I., Voss, M.R., Prakash, R.S. et al
Exercise training increases size of hippocampus and improves memory PNAS 2011 108 (7) 3017-3022; published ahead of print January 31, 2011, doi:10.1073/pnas.1015950108