The Psoas (pronounced so’-as) muscle is perhaps the most important muscle in the body that most people have never heard of. It is one of your largest and thickest muscles. If you were a cow or a pig, we’d be calling it your tenderloin. Picture two large muscles, the size of your forearms, running down each side of your spine, just behind the intestines, through your pelvis and attaching to the upper inner surface of your thigh bone. The Psoas is an important flexor of the hip and comes into play when sitting down or bending at the hip. It is also important as one of your core muscles that stabilize the body when standing.
Extended sitting can cause the Psoas to shorten. In today’s world, where many people spend their working hours, sitting in front of a monitor for 8 hours a day/ 40 hours a week (or more), this is a rather common condition. This can cause the Psoas to go into spasm any time you learn forward, causing considerable pain. If the Psoas tightens, it can increase the pressure on the lower lumbar vertebrae. This can compress the discs between the lumbar vertebrae and cause excessive curvature of the lower spine (hyperlordosis) which can lead to low back pain. If there is any narrowing of the space between the vertebrae where the spinal nerves exit the spinal cord (stenosis) this can cause sciatic pain shooting from the lower back and down the back of the leg. If only one side is tight, this can cause a curvature of the lower spine in that direction (scoliosis). A tight Psoas can cause men and women who aren’t overweight to have a ‘poochy’ stomach and no amount of crunches will correct this.
The Thomas test – how to test if your Psoas is too tight
Find a nice flat sturdy table, coffee table, or massage table. The bed will probably be too soft. Sit at the end of the table, lie down flat on your back and pull both knees up to your chest and hold them with your hands. Release one leg and let it drop as far as it will comfortably go. A healthy Psoas will allow your leg to go all the way down. The higher your thigh is off the table, the shorter your Psoas has become. Pull your leg back up and repeat the test with the other leg.
What to do if your Psoas is too tight
The best solution is prevention. Get up frequently and walk about. If you must sit all day, squirm and shift your position. Do not hook your feet under your chair as this encourages the Psoas to fire. Make sure your feet are either flat on the floor or on a foot rest for shorter individuals. Do not lean forward to look into your monitor. You should be sitting back with your head over your spine. If necessary, pull your monitor toward you rather than leaning in toward your monitor. If you sit all day at work then substitute non-sitting exercises at the gym, trade out the bike and rowing machine for an elliptical trainer or a treadmill.
Try various stretches that target the Psoas. Go to Google or Youtube and type in “psoas stretch” and you’ll find a number of effective stretches. There are a number of Yoga poses that will target your Psoas as well. You can also attempt to treat a tight Psoas by lying on your stomach with a tennis ball one to two inches to the side of your navel. If your Psoas is ‘cranky’ this will probably hurt a bit. Just relax and allow the pressure to work on your Psoas. Arching your back by raising up onto your elbows will increase the pressure. Repeat by moving the ball to the opposite side of your navel. Finally a skilled massage therapist will be able to relieve spasm and lengthen a short Psoas. This work is usually uncomfortable at best and down-right painful at its worst, but the end result is immediate relief from pain and lower back spasm, improved posture, and increased mobility.