Health & Safety Tips: Sitting Position for Safety and Comfort

Gravity constantly exerts a downward force on our bodies. Parts of our body in contact with a supporting structure (the seat of chairs, armrests, floors, etc.) will feel pressure from the structure to balance this force. Parts of our bodies that are not in contact with a supporting structure will use muscles, tendons, and ligaments to balance the force of gravity with an upward force of their own.
The body position that has the highest strength to handle the pressure felt by the supporting structure, while causing the least amount of strain on the muscles, tendons, and ligaments, is called the neutral or balanced body position.

The following recommendations outline how to maintain a neutral body position while sitting:

* Soles of the feet making an angle of 90° with the lower legs.

* Thighs approximately in a horizontal position and lower legs vertical with feet resting on the floor or on a foot rest.

* Erect or upright spine.

* No twisting of the upper torso.

* Shoulders are relaxed and upper arms hang normally at the side of the body.

* Elbows stay close to the body and are bent between 90° and 120°.

* Hands, wrists, and forearms are straight, in-line and roughly parallel to the floor.

* Head and neck is upright (not turned, tilted, flexed or extended). Generally it is in-line with the torso.

* Feet are fully supported by the floor, or a footrest may be used if the desk height is not adjustable.

* Back is fully supported with appropriate lumbar support when sitting vertical or leaning back slightly.

* Thighs and hips are supported by a well-padded seat and generally parallel to the floor.

* Knees are about the same height as the hips with the feet slightly forward.

* The in-line sight is between the horizontal and 35° below the horizontal (up and down), and with a 30° range as optimal line-of-sight angle. Vertically (side to side) the optimum viewing is directly in front of you, with 15° to either side. 35° side to side is maximum.


Although sitting requires less physical effort than standing or walking, it puts stress on the lumbar area. Over time, the effects of a sedentary lifestyle combined with a job that requires sitting can lead to various health problems, including musculoskeletal disorders (MSDs).
Learning and practicing how to sit properly can reduce stress and strain on your muscles, tendons, and skeletal system.

Photo Credit: Egronomic Trends.