Exercise has a lot of benefits. This is hardly a surprise to anyone, but exactly how much exercise is required to achieve different goals is harder to say. To get an answer to this question, a research team from the University of Pittsburgh in the USA decided to investigate how much exercise was required for an improvement in the memory of elderly people.
It turns out that it doesn't take much exercise at all to see a clear improvement.
"From our study, it seems like exercising about three times a week for at least four months is how much you need to reap the benefits in episodic memory", says Sarah Aghjayan, researcher at the University of Pittsburgh and the study's lead author, in a press release.
Unsurprisingly, the study also shows that the earlier you start exercising, the better.
"We found that there were greater improvements in memory among those who are age 55 to 68 years compared to those who are 69 to 85 years old — so intervening earlier is better", says Sarah Aghjayan.
The researchers focused on episodic memory. That memory system helps us remember, for example, the names of people, how old we are, and what it was we were supposed to pick up at the local supermarket. Episodic memory is also the memory system that is first affected in those who suffer from Alzheimer's disease.
The study is based on an analysis of a number of previous studies. By combining data from 36 studies, the researchers were able to study the results from close to 3,000 people. The combination of many studies gave the researchers the opportunity to see patterns that did not appear in the individual studies.
How much exercise and what type of exercise is optimal are questions that the researchers have not been able to answer in this study, but it is clear that all exercise is better than none at all. So a regular walk is enough to see an improvement.
"You just need a good pair of walking shoes, and you can get out there and move your body", says Sarah Aghjayan.