(California News Service) Get in shape. It's a common New Year's resolution, but research shows the Japanese practice of Shinrin-yoku - or "forest bathing" - has multiple benefits for mental and physical health. 

Studies show that forest bathing, which is basically getting outside and soaking up some nature, can improve mood. 

Dr. Suzanne Bartlett Hackenmiller, chief medical adviser for the app AllTrails - an outdoor hiking and recreation app to help find trails - said researchers from Stanford analyzed MRI data and found that time in nature actually decreases activity in the part of the brain responsible for depression and anxiety.

"They've found that 90 minutes of walking in a natural setting," said Bartlett Hackenmiller, "participants reported less of what we call rumination - just that cycle of spinning negative, stressful thoughts - than people who walked in an urban setting."

She cited a raft of studies that expand on the benefits of getting out in nature. One showed that it helps people reach their fitness goals, because exercising outdoors is more enjoyable, so people are more likely to repeat it. 

Nature walks have also been linked to better memory, a boost in immune function, and lowered stress hormones, blood pressure and cancer risk. 

Free online apps can help people venture out safely. Here's Meaghan Praznik, head of communications for AllTrails.

"Our built-in navigator helps people make sure that they're never going to miss a turn, and they can follow along the route," said Praznik. "We also have printable maps, which give people a backup map, or even the ability to download offline maps in case you are to lose service."

Other studies have shown time spent in the great outdoors with a group of friends is even more beneficial than walking alone. 

And they show that living in an area with higher "surrounding greenness" can affect the genes linked to mental health disorders, tumors and metabolic disease.