Body bay, Massage, therapy, shoulder pain, computer, office, screen Keyboard, laptop,
Body bay, Massage, therapy, shoulder pain, computer, office, screen Keyboard, laptop,

***Viewing this post on Facebook will allow you to read the text in German and Hebrew also. Link *******

Have you ever experienced a trigger point (mini spasm) being opened?

You probably have noticed that a gentle and accurate pressure will result in wide and strong pain, sometimes even referred pain in a remote location. The muscle might even start to twitch uncontrollably (local twitch response).

These are signs of Myofascial trigger points defined by physician Janet G. Travell in the 1950s.

In one of her studies [1] including 1,000 patients, Travell and her colleague demonstrated how one point feels the same in different people, therefore they could define it:

  • Therapist’s perspective – stiff area along the muscle.

  • Patient’s perspective – painful and can affect daily activities.

  • Side effects – pressure on one point will refer pain to a remote area.

What are the causes? – *DinG DInG** 1 million dollar question!

The Cinderella Hypothesis is one of my favorites. There isn’t an unanimous conception to scientifically define muscles.Here we will keep it basic: Type I and Type II.

  • Type I is the stable fiber. It can hold its strength, which is not much. Its color is red due to the blood vessels in the muscle, runs on oxygen, aerobic fiber.

  •  Type II is the strong fiber, powerful yet only for a short time. Its color is white, without many blood vessels. It is a fiber that is fueled by tri-phosphorus anosine (ATP), anaerobic cycle.

While standing, leaning, or sitting in the office, we will mainly use the stable fiber.

Example: When moving the mouse, we will use all the fibers. The stable fiber (I) stabilizes the hand on the mouse. During mouse clicks the strong fiber (II) will be used.

The stable fiber is the first to engage and the last to relax, so it is the fiber that is prone to overuse.

Office work is undynamic and sometimes stressful. Everyone knows that stress causes pain, this is where our story begins.

In a study [2] conducted in 2002, a group of scientists recruited 15 office workers. After allowing the subjects to adapt to the new working environment, we let the tests begin.

The first and third tests were the baseline (control). During those tests the subjects were assigned two pages with eight paragraphs, each paragraph contained five lines and in each line one to four letters were highlighted randomly. The subjects were instructed to mark the letters with the mouse and press the delete key only with the right hand. The control tests were without any mental stress and time frames. About 15 minutes after the first test, the experiment began. Each participant was assigned four pages (double as much) to repair in a strict time frame. Furthermore, every 15 seconds they were verbally provoked by the scientist pressuring them by yelling out, “Hurry up,”  and “Come on.” Under pressure there was an increase in muscular activity that was reflected as work efficiency, or vice versa. Wrist movements were faster. The click of the mouse button was powerful compared to the two other tests. So far so good.

One parameter seemed odd to me. Under pressure the left trapezius showed double the amount of contraction relative to the control tests. In this experiment the left hand is not active, so why is the muscle active, and twice as much?

Important note, the right trapezius increased its activity by half. Assuming the body is reletivly symmetric. Muscle fibers will not change types except in extreme cases; spinal injuries or spending time in space [3]. The left trapezius does not use fiber I because the left shoulder is not in use during the work process. The muscle is randomly contracted from the stress and does not stabilize fiber type II.

It is important to emphasise that one type of fiber will never work alone, they work as a group. 

So if you’re working with a visual display, you have good chances to experience neck or shoulder pain. Out of 512 subjects a “total of 64.3% of the patients reported that there was a relation between their current job and the neck complaints”[4].

Now it is up to you, can you relate to this information? Do you feel discomfort in one shoulder or both, when you feel the stress in your shoulder/s?

As part of my specialization in muscles, I gather information on muscle pain and their facia, so I would love for you to get in touch.

1-https://www.tandfonline.com/doi/abs/10.1080/00325481.1952.11694280

2-https://www.researchgate.net/publication/11267831_Influence_of_Time_Pressure_and_Verbal_Provocation_on_Physiological_and_Psychological_Reactions_during_Work_with_A_Computer_Mouse

3-https://www.researchgate.net/publication/11660444_Human_Skeletal_Muscle_Fiber_Type_Classifications

4-https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2213555/

This Post Has 2 Comments

  1. GreggDet

    Интересно!

    1. zurielglr

      Спасибо. 🙂

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