10/04/2014 16:48 BST | Updated 10/06/2014 06:59 BST

Marathon on Your Mind? Why Running Can Protect Your Brain

The marathon season has arrived. Last weekend, runners took to the streets of Brighton, Blackpool, Manchester, Milan and Paris to push themselves to the limits of human endurance. This weekend, Rotterdam, Vienna and, of course, London are hosting 26-mile courses for thousands more avid runners.

If you're signed up for the London marathon, you've no doubt come to the end of your training programme and are starting a week of resting, carb loading (the fun part) and psychological prepping. But as well as the physical changes you're likely to have encountered during your months of training, research suggests that your brain may actually be benefiting too.

A study published last week in the journal Neurology, has shown that doing aerobic exercise in your 20s may lead to better cognitive skills, such as quicker thinking and improved memory, later in life. The researchers demonstrated that maintaining cardio fitness, such as running, cycling or swimming, in your younger years could protect your brain in middle age.

Around 3,000 healthy people with an average age of 25 were used in the study. Each person's cardiovascular fitness was tested during the first year of the study and then again 20 years later. Cognitive tests were also completed at the start of the study and 25 years on to measure memory and thinking skills. They found that those who performed better in the cardiovascular fitness tests also performed better in the cognitive tests 25 years later.

Aerobic exercise is great for your heart health, which I'm a massive advocate for - walking and running are part of my everyday life. And the physical benefits of maintaining cardiovascular fitness are well documented. Yet the research behind its cognitive benefits has been lacking until recent years. Studies, such as this one, show that keeping fit from a young age may not only protect your heart and overall physical health, but also your mind too, potentially reducing your risk of dementia as you age.

If you're already in your 40s or 50s, you may read this and be a little concerned that you've missed the boat if you weren't the most active of 20-year-olds. But fear not. It seems being active in your later years may also hold some benefit too. A study published last year found that regular exercise in middle age can help prevent dementia later in life. The researchers reported that the most physically fit mid-lifers were almost 40% less likely to develop dementia or Alzheimer's disease by the time they were 65, compared to those who weren't as fit.

The connection between exercise and dementia is an area that has been researched for years. But until recently, most research has looked at people who already have dementia and whether exercise can improve their cognitive skills. In a recent review of research, experts have found more evidence that exercise can benefit people with dementia, improving their cognitive function and ability to carry out everyday activities.

Now, we're shifting our attention to how exercise in your earlier years may impact your thinking skills later in life. The evidence so far suggests that exercise may have a role to play at every stage of mental development and preservation - from young adulthood through to your elderly years.

This shows that being active on a regular basis not only benefits you physically, but mentally as well. And exercise should be seen as a concept of total fitness, which encompasses every aspect of our health and wellbeing, not simply to keep your body in shape.

Whether you're running the marathon on Sunday, supporting someone who is, or planning to watch it at home, be inspired to keep exercising, or start exercising. As little as 20 minutes of brisk walking a day could be enough to keep both your heart and brain healthy now and long into the future.