Steven Hirsch, a contracts attorney, never considered his line of work dangerous until he learned about the hazards of sitting.
Hirsch, who has diabetes, exercised at the gym, but still spent most of his waking hours parked in a chair staring at a computer screen.
"We're meant to move," said Hirsch, 62, who lives in Irvine. "Sitting at a job for 8, 9, 10 hours a day or more is not good for the human body."
Last January, Hirsch bought a specially designed Trek Desk to accommodate a treadmill he installed in his office at Hoag Hospital. He changed from leather dress shoes into sneakers and set the speed for 1.1 miles per hour. Still wearing a tie, he drafted contracts and sent e-mails, burning calories without breaking a sweat.
Within a few months, colleagues noticed that he'd lost weight and dropped inches from his waist.
"I did get better results when I did this," Hirsch said. "Despite going to the gym, I was sitting all day long."
A growing body of research has found that the chair in the cubicle may be more to blame than the couch for the growing American waistline and resulting health ailments.
While sitting, calorie burning plummets, electrical activity drops in the legs and the enzymes that break down fat decrease. One academic report concludes "it is time to consider excessive sitting a serious health hazard." Another study of healthy adults who exercised regularly found that those who sat the most had larger waist sizes and higher levels of cholesterol and blood sugar, which increase the risk of heart disease and diabetes.
"We try to compensate by going to the gym for 30 minutes and we think that's enough," said Joan Vernikos, the author of "Sitting Kills" and a former NASA scientist. "It can't. The body's not made that way. We need to start thinking in terms of how we can restructure our life to reintroduce small movements throughout every day."
Vernikos compares the average office building to a spaceship in outer space. She likens the muscle atrophy and loss of bone density astronauts experience without gravity to the long-term effects of uninterrupted sitting.
"Moving means you're doing something that is challenging, going against the direction of gravity," she said. "If we sit, we are reducing the level of that stimulation."
In the early 1960s, almost half of American jobs required at least moderate-intensity activity, according to a May study published in PLoS ONE, a peer reviewed online scientific journal. Now, fewer than 20 percent of jobs call for that much movement. That shift translates into more than 100 daily calories that most workers no longer burn.
While that may not sound like much, the study describes the cumulative drop in workplace exertion as accounting for "a large portion" of the increase in weight over the last 50 years.
Dr. Toni Yancey, a health services professor at UCLA, wrote a book called "Instant Recess" that offers ideas for incorporating more activity 10 minutes at a time. She notes that the earliest humans spent their days on the move in search of food and shelter, while the typical modern human sits in a car while commuting to work, only to sit in a chair all day, and then drive home to sit in front of the television.
"It's just the last 30, 40 years that we've removed all these activities," Yancey said. "People just literally don't have to move a muscle."
While Yancey, who also uses a treadmill desk, offers practical ideas for taking breaks, she stresses that workplace culture also needs to change.
"The culture says if you're a good worker, you're chained to your desk the entire day," she said. "If you get lunch, you order it in and you eat in front of your computer."
She said taking breaks to walk and stretch makes for better employees because movement stimulates the brain. She said research has proven greater productivity among assembly line workers when they stopped for activity breaks.
"We lose alertness and concentration," Yancey said. "Cognitive function is not good when we're sitting around for long periods of time. When you disrupt that, you can improve how people perform, totally unconsciously."
Hirsch, who was laid off recently from Hoag and is searching for another job, said he feels good about his investment in the treadmill desk and his results. He found he could do most of his computer work while walking, although he would step on the side rails when he needed better control to use the mouse.
He paid just under $400 for the desk and $350 for the treadmill. Hirsch's expenses didn't stop there. He eventually had to buy a smaller belt and pants.
"I was happy," he said. "My doctors were happy. My wife didn't complain."