Coming up with ideas could be as easy as a walk in the park.

We think more creatively when taking a stroll than when sitting, according to a study. Surprisingly, it is not being outside that matters, it is the exercise itself.

Researcher Marily Oppezzo said: ‘Many people anecdotally claim they do their best thinking when walking. With this study, we may finally be taking a step forward to discovering why.’

Dr Oppezzo, of Santa Clara University in California, did a series of experiments in which people undertook tests of creativity, such as playing word association games, while walking or while sitting at a desk.

In one experiment, the volunteers came up with twice as many clever ideas when walking.

The study, published in the Journal of Experimental Psychology: Learning, Memory and Cognition, also revealed that walking is more important than being outdoors.

Volunteers who walked, indoors or outdoors, came up with more ideas than those who sat inside – or were pushed in a wheelchair outside.

Dr Oppezzo said: ‘While being outdoors has many cognitive benefits, walking appears to have a very specific benefit of improving creativity.’

The benefits lasted even after sitting down, meaning big decisions needn’t necessarily be made on the hoof.

Dr Oppezzo added: ‘Walking before a meeting that requires innovation may be nearly  as useful as walking during the meeting.’

However, some things are best done sitting down.

Questions with just one right response were more accurately answered from the desk.

Dr Oppezzo said that walking is good for the mind, as well as the heart.

However, more research is needed to work out how it fires the imagination.