Pain

Best Office Chair Seat Cushion PT.4- Shear

Written by Stacey Mullis, OTR/L, ATP, NPI-CPS | Jan 29, 2023 2:00:00 PM

If you're not familiar with the concept of shear, you're not alone.

While shear forces are a common occurrence in everyday life, they are often overlooked or misunderstood. In this blog, we'll introduce the concept of shear and explain how it can have a significant impact on the human body, particularly when it comes to sitting.

So, what is shear? Simply put, shear is a combination of downward pressure and friction that occurs when two surfaces are in contact with each other. In the context of sitting, shear forces can be a major contributor to discomfort and pain, particularly in the lower back, buttocks, and legs.

When a person sits in a chair, the weight of the upper body puts downward pressure on the chair, while the friction between the body and the chair helps to keep the person from sliding off. These forces can create shear stress on the body, particularly in areas where the skin is in contact with the chair.

Thankfully we have pain receptors that get irritated when we experience shear, causing us to change positions. But the impact of shear forces on the body while sitting can range from mild discomfort to serious injury. 

So, how can you minimize the impact of shear forces while sitting? Here are a few strategies to consider:

  • 1 Use a chair with pelvis support: Pelvis support minimizes forward sliding on the seat and keeps the spine in good alignment

  • 2 Adjust the chair to the proper height: A chair that is too low or too high can increase the amount of shear force on the body, so it's important to adjust the chair to the proper height for your body.

  • 3 Take breaks and stand up: Sitting for long periods of time can increase the amount of shear force on the body, so it's important to take breaks and stand up every hour or so to stretch and move around.

  • 4 Check your cushion: Choose a chair with a contoured, pressure relieving cushion.

Anthros understands the potential impacts of shear and has designed a chair to minimize its effects.

Shear

University of Pittsburgh Study
Low Values are Desirable

  • ANTHROS7.2
  • ALL33 BACKSTRONG10
  • STEELCASE LEAP10.5
  • STEELCASE GESTURE12.9
  • HUMANSCALE FREEDOM13
  • X-CHAIR X316
  • HERMAN MILLER EMBODY16.1
  • SECRET LAB TITAN17.1
  • MAXNOMIC DOMINATOR21.1
  • HERMAN MILLER AERON23
Less 0N
  • 5
  • 10
  • 15
  • 20
More 25N

1 The Cushion

Using anthropometric data and 3D human modeling, we designed a state-of-the-art low-shear cushion. This was validated through standardized bench testing against nine competitors' cushions.

2 The Independently Adjustable Two-Part Back System

The low back pelvis support adjusts to support and hold the pelvis in neutral. This prevents the pelvis from rolling back and sliding forward which would induce shear forces.

 
 

3 Tilt

One of the biggest causes of shear to the low back and buttocks is reclining. It causes the pelvis to roll back and slide forward. In tilt, the back and seat move together, maintaining the pelvis position and upright posture.

As you can see, Anthros understands sitting at the cellular level and has truly designed a chair with the human body in mind.

If you are looking to improve posture while sitting, look no further than Anthros.

Anthros is the only chair in the world that is guaranteed to improve posture or your money back. The science-backed, patented design, is registered with the FDA as a posture-improving chair and is proven to have the lowest pressure (most comfortable) cushion on the planet (verified by university testing).

Take the next step to reducing pain, increasing comfort, and maximizing performance!

 
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