A Harvard-trained psychologist shows you how to destress at work in just 2 minutes

If you're constantly feeling overwhelmed at work, you're not alone.

Americans are more stressed than they have been at any other time in the past decade, according to data from the American Psychological Association. Professionals are working longer hours, leaving vacation days unclaimed and worrying more about money.

But there is some good news. According to Marlynn Wei, a board-certified Harvard and Yale-trained psychiatrist, you can significantly reduce your stress levels in just a few minutes.

"I do actually work with a lot of professionals who come to me to try to reduce stress," Dr. Wei tells CNBC. "The first thing I tell them is a very portable, easy to use strategy. It's two to three minutes of simple, rhythmic paced breathing," she says.

Marlynn Wei, Harvard and Yale-trained psychiatrist and yoga instructor, recommends a simple breathing exercise to relax while at the office.

Photo by Martin Bentsen

Here's Dr. Wei's strategy:

• Set a timer for two or three minutes.
• Focus on your breath.
• Take a deep breath through your nose while you count to five.
• Hold your breath for five counts.
• Exhale for five counts.
• Repeat for the remaining time, and notice how your breath becomes deeper.

Rhythmic breathing has a mental effect, says Dr. Wei, who co-authored "The Harvard Medical School Guide to Yoga." It draws your attention away from what is stressing you and toward what you're feeling, which has a calming effect. In addition, you trigger positive psychological changes.

"This type of breathing can reduce a lot of the fight or flight stress system that's going on," she says.

The exercise activates the parasympathetic nervous system, which triggers, among other things, the body to rest.

While experts, including Dr. Wei, normally recommend doing breathing exercises for 10 minutes or more, the psychiatrist says you can feel the stress-reducing effects after just a few minutes.

In fact, you can practice the breathing exercise on your commute, at your desk, in the bathroom or on a short walk around your office building.

"The more you practice it," Dr. Wei says, "the easier it becomes."

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