Your chair is trying to kill you.
In a survey of 222,000 Australians published this year, people who sat more than 11 hours a day had a 40 percent greater risk of dying within the next three years compared to those who parked their butts for fewer than four hours daily. And even if you exercise regularly, the chair will still try to sabotage you—rounding your shoulders forward, collapsing your chest, tightening your hips, and turning the natural "s" shape of your back into an ugly, painful "c."
"First, the pelvis starts to tilt under, into what's called a posterior tilt," says Aaron Brooks, a biomechanics expert and owner of Perfect Postures in Auburndale, MA. (Search: How to create an ergonomic workspace) "When that happens, the low back loses its curvature, flattening out. The thoracic [upper] spine starts to go into too much flexion, so the shoulders round forward, and the head moves forward. The shoulders also internally rotate, and then the hands and forearms pronate, or turn inward."
And when it comes to our endless conference calls, web browsing, and nightly TV-watching, practice makes imperfect: "Whatever you do, your body adapts to it, and gets comfortable being in that position," says Jeremy Frisch, owner and director of Achieve Performance Training in Clinton, MA. "By sitting all the time, muscles in the front of the body get tight and locked up, and muscles in the back get weak."
"Even if you work out really hard for an hour or two every day, you still have to look at the rest of your day," Frisch says. That is, an hour of vigorous movement doesn't counter 7 to 10 on your butt. "You have to get up and move around."
It's time to fight back—and you don't even have to leave the office. Hop out of your chair every 20 minutes to clear your mind and start healing your posture with these simple, inconspicuous stretches that use a tool you never knew was there: your doorframe.
Step Through to Stretch Your Chest
Start with a simple chest stretch, says Frisch. Stand on the threshold of the door, and place your right forearm inside the door on the right side of the jamb, with your palm against the jamb at about shoulder height. In this position, twist your chest slightly through the door to stretch your chest—alternately, you can take a step forward with your right foot, keeping your left foot in the threshold.
To change the stretch slightly, try twisting your head to the left, says Brooks. And add strength and stretch for tired forearms by bending your wrist backward off the jamb so your palm faces the ceiling, suggests Chrissy Carter, a yoga teacher and trainer at YogaWorks in New York. (Download our free 20-minute yoga workout!)
Carter also recommends a double-armed version of this stretch, a move that mimics using a yoga rope wall. To do it, place both forearms in the position described above at the same time. From here, lean forward through the doorframe. "It's almost like the Titanic position," she says.
Too easy? Walk your feet behind you as you lean forward to increase the intensity of the double-armed stretch.
Stand Against a Corner to Fix Your Thoracic Spine
Only got a second? Open your chest some more and encourage proper thoracic spine position with the lightning-fast "No Money" drill from Eric Cressey, C.S.C.S., of Cressey Performance in Hudson, MA.
(Video: Sculpt a beautiful back)
Start by standing against the corner of the doorframe so that the edge of the jamb bisects your body. Stand tall and place your hands cupped in front of your belly button, elbows at your sides. Without changing the bend in your elbows, pinch your shoulder blades together until your hands point out to either side. Return to the start position and repeat.
Throw Your Hands in the Air
If you're working through a tough problem or just slogging through a Tuesday afternoon, get the blood flowing with your arms overhead in this head-clearing stretch from Frisch.
Cross your forearms overhead and rest them inside the top of the frame as you stand in the threshold. In this position, lean forward, much as you did in Carter's two-armed "Titanic" stretch. For a deeper stretch, walk your feet back while continuing to lean forward.
While you're up, strengthen and lengthen the side of your body, suggests Brooks. Grab the side of the doorframe with one hand at shoulder height. Bend your body forward by rounding your upper back, dropping your head, and sucking in your abdominals to take the curve out of your lower back. In this position, you should feel a stretch through your arm and down the side of your body.
Use Late-Night Sessions to Stretch Your Legs
Your hips also suffer from all-day sitting, but it's tough to stretch and loosen them without lying down—not exactly professional-advancement behavior. But if you're working late and find yourself alone to burn the midnight oil, try this on-your-back series from Carter to stretch your hamstrings, glutes, and hips.
Related: Think you're limber? Take our flexibility test
Start by lying with your right leg resting straight up the right side of the doorframe, with your butt close the casing. Your left leg should be stretched straight through the door, flat on the floor. In this position, you'll get a great hamstring stretch—to increase the intensity, scoot your butt closer to the frame, so your right leg comes closer to vertical.
Transition to a glute stretch by bending your right knee and sliding your foot down so it's flat against the frame. "The wall is basically pushing your knee into the chest here," she says.
Next, move into a hip stretch. With your left leg still outstretched, slide your butt to the left side of the doorframe. Bend your right knee so that your foot rests against the inside of the left side of the jamb, forming a figure-four with your legs. In this position, gently press on your right knee with your right arm to increase the stretch. To increase the intensity, slight your butt further into the frame; to decrease the intensity, slide it back. Repeat the entire sequence on your left side.
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