A series of recent studies have added credence to the notion that physical activity is far more effective than mental exercises, such as crosswords or puzzles, in staving off dementia.

It's been a long-held belief that keeping the mind active is the best way to fight cognitive decline – with a series of recent ‘brain training’ computer games cashing in on the notion – but researchers say that money would be better spent in the gym, where the results can be instant.

A recent study from the University of Pittsburgh showed the immediate positive effect brisk outdoor walks had on the brains of middle aged and elderly men and women, compare to those who were inactive.

Focusing on those aged 55 to 80, researchers found that the regular workouts increased the size of the hippocampus - the brain’s memory hub - knocking almost two years off its biological age.

Whereas the brain usually shrinks with age by around one per cent per year, the brains of the men and women who exercised by walking for 40-minutes three times a week expanded by up to two per cent.

The findings are supported by Cardiff University’s 35-year study, published in December 2013, examining the impact of five lifestyle behaviours on dementia and cognitive decline.

Researchers discovered that those who achieved four out of five “healthy behaviours” - regular exercise, non-smoking, low weight, healthy diet and low alcohol intake - enjoyed a 60 per cent reduction in dementia and cognitive decline, with regular exercise highlighted as having the greatest impact.

In terms of the role mental stimulation has to play, a UK study published recently in the journal Nature examined the effect of using commercial brain-training games like the Nintendo DS on 11,000 people during a six-week experiment.

The researchers found that across a range of tests, the volunteers did no better than a control group that spent a similar amount of time just surfing the internet.

Studies on brain training have shown some effectiveness in slowing cognitive decline, but not in preventing it, while other research has suggested that these exercises may help protect the memory, but won’t guard against dementia.

The role exercise can play in combating cognitive decline was previously touched upon by Health Club Management managing director Liz Terry, who concluded in a 2009 editorial that “all the evidence suggests our industry has an important part to play in helping vulnerable people who are battling this challenge."

In last month's issue of Health Club Management Kate Cracknell looked at how to successfully engage the elderly and get them active at gyms and health clubs.