This podcast is one minute long. If you listen while going for a walk in a park or working in a garden, you're 20% of the way to giving your mental health a good boost. Because exercising in natural areas is not only good for your physical health - it can improve your mood and sense of well-being in as little as five minutes. So says research in the journal Environmental Health and Technology. Exercise alone is known to make you happier. So is being in a natural setting. So scientists at the University of Essex wanted to see the effect of combining the two. They evaluated 10 different U.K. studies involving more than 1,200 people. Participants had taken part in activities such as gardening, sailing and country walks, and rated their mood and self-esteem. The research showed that both areas get a significant boost with as little as five minutes of outdoor exercise. And people with mental disorders benefitted the most. The study authors say this is the first study to quantify the amount of time needed to get a positive effect. So download a few podcasts and head out for a walk in the park.