Fresh air really can put a spring in your step

From being stuck in the house to deskbound workers, a simple stroll in the open air is as revitalising as a caffeine-fuelled injection of a favourite brew, US researchers found. And the benefits do not come from being more active, as people were more energised outdoors even if they were doing nothing.

The bond between the human body and the natural world makes "people feel more alive" said psychology professor Richard Ryan for the Journal of Environmental Psychology.

Prof Ryan, of the University of Rochester, New York, added: "Nature is fuel for the soul. Often when we feel depleted we reach for a cup of coffee, but this suggests a better way to get energised is to connect with nature."

His team conducted five different experiments on 537 student volunteers, exposing them to various situations both active and sedentary inside and outside, in the open or by a river.

They then measured their energy levels and moods throughout the day in different environments and while engaged in various activities.

They were also told to imagine themselves in different outdoor surroundings to see if energy levels rose. The results showed the students felt more energetic when they imagined themselves outside and a massive increase in vitality after just 20 minutes in the open air.