How We Work.
The compelling problem for ergonomics today is not sitting, but sitting badly. When standing postures are used to avoid sitting, the problem from sitting poorly is not addressed, and there are increased costs and added health risks from standing. Our practice to improve sitting is unique to the industry, and there is considerable long-term value to resolve the cause of disease for the injured worker and improve productivity. Our primary focus is to address the most basic ergonomic principle: adapt the workstation so the body works best. We use a novel approach to find the body’s strong posture (HipIndex™), measure the optimal strength (HipTorque™), and integrate the workstation (ActivSeating™) to allow the work to be done efficiently..
Ergonomic recommendations typically use a reclined chair to sit more easily—the postural muscles are completely relaxed and the legs are unloaded onto a footrest. This “reclined-leisure seating” approach has two problems: first, it is relaxed sitting posture has been linked to the long-term health risks for diabetes, obesity and heart disease. Second, when reclined postures are used for work that requires forward interest or close attention, the spine bends forward with a greater risk of musculoskeletal problems. Notwithstanding the long-term health risks, slumped postures can easily be uncomfortable for the neck and low back, and are also seen with cumulative trauma problems in the arm and hand.
Poor spinal postures in the chair are very common at work, but seldom noticed. Often, it is how the chair is used at work that will cause slumping, and standing may seem the only reasonable alternative to avoid pain. The range of spine movement in sitting is not very large—there is only 20-30 degrees difference from the very best to the worst posture, and it is easy to get stuck in the worst position. Bad sitting posture was overlooked because the ergonomic consultant did not have a way to easily show spine posture during work.
The HipIndex™ method was developed specifically to demonstrate good seated spine position at any job (Fitzsimmons 2014). The observation does not require clinical experience to find the best position. Our goal is to show neutral spine posture as the best practice for ergonomic recommendation. Our consulting outcomes prove that supporting neutral spine posture during seated work is the primary solution for pain and cumulative trauma. That solution requires only that we sit better, and not stand up to avoid sitting badly.
When there is movement at the waist in upright sitting, we know the low back is in the strongest, “neutral position,” and the postural muscles are engaged (Dunk 2009). The slight forward rotation movement of the pelvis, as the torso posture is corrected into “tall sitting” is the sign the spine has room to move. This movement shows when the postural muscles are working in their strongest position. When the head lines up over the pelvis, the “reset” movement can happen in upright sitting, or neutral-spine posture.
Leg strength is important to hold the torso upright and engage the postural muscles. The strong upright torso fully engages the postural muscles using leg strength. Strong sitting allows torso movement more easily, the best postures are more easily sustained, and the physiology of blood glucose and fatty acid metabolism can get improve without standing. The HipTorque™ approach to measure leg strength is distinct—we do not move the body to a set of predetermined angles—we find the strongest posture to do the work, and then move the workstation to support the body. Postural problems are minimized when the strongest muscles are used how they work best. That sweet spot for the best strength of the postural muscles is fairly easy to find. If more objective measures are needed, a smart-phone application (HipTorque™) uses an accelerometer to determine the chair height with the best strength.