When you’re at work, with very few exceptions, most of us will find ourselves sitting at a desk − despite all of the health detriments and shortened life expectancy associated with doing so.

The average U.S. adult sits for nine to 10 hours each day, according to Dr. Joseph Mercola in his extensive article "Here's What Sitting Too Long Does to Your Body."

Will you really die sooner if you sit instead of using a standing desk?Maybe not right away, but your life expectancy will decrease, according to British Medical Journal, which concluded the more hours you spend sitting in a day, the shorter your lifespan may be.

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In the “Sedentary behaviour and life expectancy in the USA” study, researchers found that reducing the average time you spend sitting down to less than three hours a day could increase your life expectancy by two years.

In 2011, the Centers for Disease Control and Prevention released a study that advocated the reduction of prolonged sitting time by using a sit-stand device. Then, in 2013, the American Medical Association approved a new policy on sitting in the workplace, urging employers to allow for standing work stations and isometric balls.

Dr. James Levine, co-director of the Mayo Clinic/Arizona State University Solutions Initiative and author of the book "Get Up! Why Your Chair Is Killing You and What You Can Do About It," is the inventor of the treadmill desk. Through three decades of research funded by the National Institutes of Health, Dr. Levine's team has pioneered the science of nonexercise activity thermogenesis (NEAT) and studied the harm associated with too much sitting, which is a major cause of obesity, diabetes, breast cancer and 24 more chronic diseases and conditions.

Maura Howard tries to log about 3 miles per workday on a treadmill desk station at Salo, a financial staffing company in downtown Minneapolis. She said regular walking helps her avoid after-lunch drowsiness. It’s also good for her health. With its “Get Fit Don’t Sit Day” (May 6), the American Diabetes Association hopes to encourage people to sit less and move more. CONTRIBUTED BY RICHARD SENNOTT/MINNEAPOLIS STAR TRIBUNE/MCT

Credit: Richard Sennott

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Credit: Richard Sennott

Health risks of sitting too long

Sitting for too long can damage your heart, pancreas, digestion system and brain. Leg disorders can include varicose veins, blood clots, weak bones and osteoporosis. In addition, sitting for long periods can lead to posture problems, including strained neck, sore shoulders, back problems and an increased risk of herniated disks, muscle degeneration and hip problems.

Standing vs. gym time

Instead of going to the gym for a few hours a week to offset over-sitting, Dr. Levine said in this MayoClinic.org article that a more effective alternative is more moving and standing whenever possible while working. Dr. Mercola advises standing whenever possible and trying to walk 10,000 steps a day or just over three to five miles.

The benefits of a standing desk can include better posture, less lower back pain and a feeling of having more energy. You may also burn more calories.

Standing isn’t for everyone

Unfortunately, they can also lead to foot pain and swollen calves and ankles, so it's important to wear comfortable, supportive shoes.

For those of us who must sit for long periods, Posture expert Esther Gokhale offers a method for sitting properly, emphazsizing what she calls stack sitting and stretch sitting.

  • Stack sitting is when you allow the bones in your spine to stack well and permit the muscles alongside them to relax by sitting with your behind sticking out slightly behind you.
  • Stretch sitting is another way to lengthen your spine by using your backrest as a traction device.