Occupational Ergonomics – Working and Walking Postures

As you may know, proper ergonomics helps to prevent many work-related injuries. In addition to having a proper workstation setup, proper lifting mechanics are also important. As we had discussed in an earlier blog post, our bodies act as a lever when we are lifting things or moving things, so it is very important to understand how to exert energy correctly perform the task without injuring yourself. Posture also plays an important role in minimizing discomfort and injury, or the risk of injury while you work. In addition, having good posture aligns your body so that you are putting less stress on supporting ligaments, tendons, and muscles.

The picture below shows some of the common wrist movements that can lead to discomfort or injury if overused or in those positions for an extended period of time. Prolonged wrist flexion and extension increase the pressure placed on the wrists, which increases your chance for Carpal Tunnel Syndrome (CTS). Ulnar or radial deviation of more than 20 degrees will also increase your chance to develop CTS. This is why we always recommend taking breaks from typing too long on a keyboard at your computer desks or invest in an ergonomic keyboard that can help prevent ulnar or radial deviations.

http://getmgs.com/wp-content/uploads/2012/11/Wrist-Movement-Pic.gif

Here are a few other things to keep in mind relating to other joints in our daily work activities.

• If shoulder abduction (raising your arms to the side) and shoulder flexion (raising your arms forward) is more than 60 degrees for more than one hour a day, this will increase neck and shoulder pain.
• If you are working with your hands above your shoulder level, this increases your risk for tendinitis
• If you bend your neck forward and downward (such as looking down on a smartphone) for a prolonged period of time, this will quickly lead to more shoulder and neck pain
• Improper bending at lower back increases low back pain (make sure to lift properly!)
• Twisting while lifting, pushing, pulling or lowering something will expose your back to injury

A few notes on correct sitting posture:

• Angle between upper arm and forearm should be 70-135 degrees. When working at a desk, try to keep your forearms parallel to the ground, and not too close to your chest for long periods of time
• Angle between the upper and lower leg is 60-100 degrees. Your feet should be as flat to the floor as possible (This equates to an angle of 90 degrees between the upper and lower legs).
• Angle between the torso and thigh is 90 – 100 deg
• feet are flat on the floor
• Monitor should be position at slightly below eye level, for viewing angle about 30 deg.  Viewing distance between 18-24 inches

A few notes on correct standing posture:

• Your work surface should be 2 to 4 inches below elbow height for precision work
• Your work surfaces should be 4 to 6 inches below elbow height if lifting low weights
• Your work surfaces should be 6 to 16 inches below elbow height if lifting heavyweights
• Your workspace should have the option to be adjusted or tilted to prevent neck, shoulder, arm strain

Here is an image of a work station with proper ergonomics in mind:

http://www.ergonomics-info.com/image-files/ergonomics-training.jpg

Posture Tips for Walking Harder, Faster, and Farther

• Lower your chin parallel to the ground; don’t jut your head forward.
• Consciously draw your navel in towards your spine and keep your back straight. (Think “tall” but not stiff.)
• Lift your chest and comfortably draw your shoulders down your back.
• As your propel yourself forward with each step, it may feel natural to lean slightly forward. Lean from your ankles, not your hips.
• Keep your elbows bent 90 degrees and don’t swing your arms too high or cross them in front of you.
• If you want to increase your walking speed, take smaller steps instead of wider ones.
• Most people automatically rotate their hips a little as they walk. If you don’t do this naturally, try to develop the habit to reduce the impact on your joints.
• Land on your heels with the front of your feet raised, rolling into the next step. When you land flat-footed, you create stress to your knees, ankles, and feet.
• Finally, pay attention to how your walking shoes feel. Walking shoes wear out from the inside, so it’s not always easy to tell when you need a new pair.

If you want to know more about posture and how to correct a posture, please send me an email or leave me a comment.