New York, Feb 26 (IANS): Amid the ongoing board exams, spending as little as 10 minutes in a natural setting like the neighbourhood park can help students feel happier and lessen the effects of both physical and mental stress, say researchers.

The team from Cornell University in the US found that 10-50 minutes in natural spaces was the most effective to improve mood, focus and physiological markers like blood pressure and heart rate.

The study, published in the journal Frontiers in Psychology, aims to provide an easily-achievable dosage that physicians can prescribe as a preventive measure against high levels of stress, anxiety, depression and other mental health issues college students face.

"It doesn't take much time for the positive benefits to kick in -- we're talking 10 minutes outside in a space with nature," said study lead author Gen Meredith from the Cornell University.

"We firmly believe that every student, no matter what subject or how high their workload, has that much discretionary time each day, or at least a few times per week," Meredith added.

For the findings, the research team reviewed studies that examined the effects of nature on people of college age (no younger than 15, no older than 30) to discover how much time students should be spending outside and what they should be doing while they're there.

They found that 10-50 minutes in natural spaces was the most effective to improve mood, focus and physiological markers like blood pressure and heart rate.

"It's not that there's a decline after 50 minutes, but rather that the physiological and self-reported psychological benefits tend to plateau after that," said study co-author Donald Rakow.

To enjoy the positive effects of being outside, students need only to be sitting or walking, the two primary activities the researchers examined in an effort to provide accessible recommendations.

"This is an opportunity to challenge our thinking around what nature can be. It is really all around us: trees, a planter with flowers, a grassy quad or a wooded area," Meredith said.

The impetus for this work is a movement toward prescribing time in nature as a way to prevent or improve stress and anxiety, while also supporting physical and mental health outcomes.