Do you feel stifled by the four walls of your office or cubicle?

There's a reason for that.

Trapping ourselves indoors has created what health experts call a "nature deficit disorder" -- depression or anxiety resulting from too little time spend outside. Getting outdoors can do great things for your health. Reducing stress, lowering blood pressure and improving immune function are among nature’s health benefits. What's more, incorporating elements of nature into your workday can also give your brain a boost, resulting in increased productivity, focus and creativity.

Harvard physician Eva M. Selhub, co-author of Your Brain on Nature, says a drop of nature is like a drop of morphine to the brain, since it “stimulates reward neurons in your brain. It turns off the stress response which means you have lower cortisol levels, lower heart rate and blood pressure and improved immune response."

Turning off the sensors that are involved in the stress response allows the higher brain centers to be accessed, resulting in increased concentration, improved memory, greater creativity and productivity and reduced mental fatigue. While Selhub says spending 20 minutes a day outdoors is recommended, studies have shown even looking at photographs of nature can deliver some of the same cognitive benefits as physically being outdoors. A 2008 study at the University of Michigan showed students who looked at photos of nature performed better on tests of attention and working memory than those who looked at photographs of urban scenes.

Related: How to Create An Autism-Friendly Workplace

Follow these tips to incorporate nature into your workday:

Take meetings out of the boardroom. Hosting meetings outdoors is an easy way to get your daily dose of nature without taking a break from the job. By removing yourself from familiar office surroundings, you can literally step outside the box and feel freer to brainstorm ideas. Amit Bendov, CEO of SiSense,, a business-intelligence and analytics-software company, invites a different employee each day for “walk and talk” meetings.  "It's a great way to get people away from their computer screens [and] it provides employees with a safe environment to bring up concerns, a positive atmosphere to brainstorm and a literal and metaphoric breath of fresh air," says Bendov.

Mix business with fitness. Jason Ovitt, CEO of Asylum Public Relations, cycles to work every day and at the end of each day, he and co-founder Laura Baumgartner ride for 30 minutes together to go over accounts and to-do lists for the next day. "It’s a great time to solve problems while de-stressing because we aren’t stuck in the office glued to our computer screens and phones and there are no technology distractions, incoming emails or phone calls to take us off topic,” says Baumgartner. 

Related: How to Prevent Those Awful Monday Blues

Take your laptop outdoors. Working at the park or an outdoor cafe can provide the mental stimulation required to get through the day. Lettuce, an online inventory and order management software company located in Venice, Calif., encourages employees to take their work to the company's rooftop lounge to enjoy the panoramic ocean view. "When we take time in our day to step away from the desk to enjoy where we are, we come back re-energized," says CEO and co-founder Raad Mobrem. "It’s helped us to come up with more creative solutions and maintain a generally upbeat and united office environment."

Dine al fresco. Since we know eating from your desk is bad for your health, lunchtime is a great opportunity to grab a breath of fresh air. PMBC Group, a health and technology public relations firm, organizes 20-30 minute lunchtime walks two to three times a week and brown bag outdoor lunches every Thursdays. "Eating outside together bonds us as a team," says Ola Danilina, CEO and founder. She says moving between the indoors and outdoors gives her team more energy and improves productivity.

Add nature to your office. Even if you can't get outdoors during the day, you can still reap the benefits of nature. Selhub says simply surrounding your office with plants or having a view of green spaces (such as a park or even a single tree) can deliver some of the same improvements in mental function as spending time outdoors.

Related: 6 Ways to Promote Wellness In Your Office