The Elevon was born out of the unique research performed by iMovR on the ergonomics of working on a computer while standing or walking. While most every other ergonomics products company in the industry relies on decades-old research performed on seated computer users, iMovR has been on the forefront of studying the wholly different ergonomics issues that are introduced in the standing and walking modalities.
The following is a primer on ergonomics for the layperson, but also contains links to more technical details that might be of interest to professional ergonomists (since most ergonomics training programs have yet to include standing desk and treadmill desk ergonomics in the syllabus), and those who just want to better understand what happens at the muscular and skeletal level.
What does it mean to be in a Neutral Position?
The most neutral position occurs when all muscles are at rest, such as when lying in bed. Or picture an astronaut asleep in weightlessness. This cannot be achieved when working in front of a computer, for obvious reasons. The solution is to create a position where:
- the largest/strongest/most powerful muscles do the most work,
- muscles are not doing unnecessary work just to maintain the position, and
- muscles are doing work in their optimal strength range (to prevent muscle and tendon strain).
Why is it Important to work in a Neutral Posture?
One common misconception about desk work is that we should work in a completely relaxed position. This is false.
A relaxed position means that muscles are not active. if muscles are relaxed and you are not lying flat, then there is something holding you up. If this is not muscles then it must be ligaments and bones hanging off each other.
The job of the ligament is to hold bones together and to keep your skeleton in place, But they are not designed to do the job on their own indefinitely.
Chronic stress or tension on a ligament, like any soft tissue in the body, will cause it to lengthen. This will not happen overnight or even in a week, but over multiple months and years of unsupported stress put on ligaments, they will inevitably lengthen. When they lengthen they fail to fully support the bones, and put even more stress on surrounding ligaments and tissues. When ligaments start lengthening and failing to support their surrounding structures, it causes the body to compensate in ways that are usually cause pain.
Another problem arises when these ligaments are damaged because they have a very, very low blood supply. This means that it takes ligaments a very long time to heal themselves. Have you ever heard that a sprained ankle can be worse than a broken ankle? That is so exactly for this reason. Ligaments have such a low blood supply that they take even longer to heal than bone!
So how does one achieve a neutral working posture possible?
The main thing is to take strain off the ligaments. This can be done in a number of ways, the most obvious being changing positions. By changing positions often the natural elastic properties of the ligaments will pull them back to where they should be without creating permanent damage. By constantly changing positions you benefit yourself in a multitude of other ways, too, including improving brain function, increasing blood flow, and staying alert and awake.
Another effective way to take the stress of your ligaments is to use your very strong and very capable muscles. These start with the “core” muscles the support your spine, extending out all the way so that your fingers are supported. Muscles are one of the best ways to take some of the load off of ligaments. Muscles are the perfect organ for this job for a few reasons. 1) they can stretch and shorten on command to be the perfect length and the perfect tension for any job; 2) they cannot be overstretched like ligaments can, because they contract; 3) if there were to be an injury to the muscle, it has an incredibly high blood flow so it can heal very quickly. (Think of how long a pulled muscle takes to heal compared to a sprained joint; 1-2 weeks versus 8+ weeks).
While using muscles is important, It is also important to use the right muscles and in the right way. Core muscles such as abdominals, hip flexors/extensors and pectorals are much larger and stronger muscles than excessory muscles such as the multifidie in the back, or the scalenes in the neck, and are much better suited to do the job of keeping the body in the correct position and maintaining posture. Using the excessory muscles for jobs that the core muscles are designed to do puts undue stress on these muscles.
By working in a neutral position, the body is not relying on these ligaments, or excessory muscles to maintain its’ position. Rather it is using the large muscles, and natural gravitational pull to let bones rest on top of one another as they should. When one considers how much time is really spent at a work station, it is imperative to keep your body in the most natural and neutral position possible, because even the slightest misalignment of a joint over the thousands of hours a year spent in that position will have negative effects and will lead to pain, injury, overuse and arthritis.
Focus: The Spine
The spine is one of, if not the most important part of the body to keep in neutral. One of the reasons is that there are 33 different bones, that all have to work in unison for any motion, anywhere in the body. The other reason is that the spinal cord which connects all the nerves in the body to the brain is contained inside the spinal canal. This is an incredibly sensitive organ and any non-normal force on it can translate to pain, numbness or discomfort anywhere in the body.
One of the most common issues with office life and the spine is that sitting with poor posture for prolonged periods often this results in low back pain. But why?
LOW BACK: as you sit in your relaxed position, putting your weight on the ligaments, your spine is curved as you sit so that your tail bone is underneath you. if you relax, you spine flexes as your lower back falls down and back into the seat rest. (slouching position) this stretches the posterior ligaments on your spine and compresses the anterior ligaments. over time, without proper muscle help and posture, this will weaken these ligaments and push the intervertebral disc backward as it is wedged out of the spine. as this disc pushes out (bulges or herniates) it can start pressing on the spinal cord. This chronic issue called a herniated disc, or bulging disc causes low back pain, and can also cause pain to shoot down the legs into the feet as it becomes more severe. By standing, this stretching of the posterior aspect of the spine and compression of the anterior disk is relieved.
The same issue of relaxing, tilting your head too far forward or too far back to keep your eyes on the computer screen causes similar issues with the vertebrae and the intervertebral discs in the neck.
Focus: The Shoulders
When we talk about the shoulders and their correct position we are actually talking about 3 separate joints:
- The glenohumeral joint which is what everyone thinks of with a shoulder joint the ball and socket of the arm connecting to the shoulder
- The scapulothoracic joint, which is how the shoulder connects to the spine.
- The acromioclavicular joint (AC joint) which is how the shoulder connects to the collarbone, which connects to the rib cage
All three of these joints must be working in unison for the optimal positioning. Because these joints are holding the arms in position – which are relatively light – there is less worry about gravity stressing out the ligaments. The concern here is more with arthritis and muscle strains. The AC joint and the glenohumeral joint are very prone to arthritis. Arthritis is the building up of bone around the joint that leads to pain and loss of mobility.
The rotator cuff muscles are also very susceptible to muscle strain, overuse and even tear. These muscles are responsible for rotation motions of the shoulder joint (which happen all the time in performing office work).
Focus: The Wrists
It is very important to keep your wrists in an ergonomically sound position so as to prevent overstress injuries. The wrist is one of the most commonly stressed joints in office workers – mostly due to carpal tunnel syndrome. All of the tendons that move the fingers run through the carpal tunnel, which is covered with the transverse carpal ligament. When the wrist is straight with the forearm, these tendons run smoothly through the tunnel and function perfectly. However, if the wrist is put in an angled position to the forearm (too much flexion, extension or deviation) these tendons are stressed and can push up against the median nerve, causing pain and discomfort.
What muscles and joints are affected when working at a computer?
|Important joints to consider when using a standing desk||Joint Motions||Major Muscles||Notes|
|intervertebral joints (cervical spine)||flexion||SCM (sternocleidomastoid), scalenes, levator scapulae||crucial to have the “S” curve in the spine when standing at your desk.
the head must be balanced on top on the neck so that the extensors and flexors are not constantly tense, looking too far up, or down is very very bad for fatigue and can cause stress injury.
|extension||semispinalis, rectus capitis, obliquus capitis|
|horizontal rotation||SCM Contralaterally|
|lateral flexion||SCM, scalenes, levator scap|
|lateral extension||same muscles as extension, but on opposite side.|
|intervertebral joints (thoracic spine)||abdominals, obliques, spinal extensors,|
|intervertebral joints (lumbar spine||abdominals, obliques, spinal extensors, hip fliexors, hip extensors.|
|scapular-thoracic joint||elevation||levator scapule,
serratus anterior, trapezius, deltoid, pectorals,
|upward rotation||levator scapule, serratus anterior|
|downward rotation||lower trap, rhomboids|
|protraction||serratus anterior, pec major/minor|
|acromio-clavicular joint (AC joint)||upward rotation||trapezius, deltoid|
|downward rotation||pec major, deltoid|
|elevation||levator scapule, scalenes|
|depression||pec major, rhomboids|
|protraction||pec major, pec minor, anterior deltoid|
|retraction||trapezius, rhomboids, posterior deltoid|
|gleno-humeral joint||adduction||latissimus dorsi, long head of triceps|
|abduction||deltoid, supraspinatus, upper trap|
|horizontal adduction||pec major, pec minor, anterior deltoid|
|horizontal abduction||posterior deltiod, latissimus dorsi, rhomboids,|
|humero-ulnar joint||flexion||biceps bracii, brachioradialis, brachialis|
|radio-ulnar joint||Pronation||pronator teres, pronator quadratus, brachioradialis,||brachioradialis biggest/ strongest muscle in group, is responsible for pulling forearm back to “neutral” from either supination or pronation, the reason why our neutral position is with the ulna and 5th metacarpal resting on the table with an imaginary line from through the thumb pointed toward the opposite armpit.|
|radio-carpal joint||flexion||wrist flexors: flexor carpi ulnaris, flexor carpi radialis, flexor digitorum longus,|
|extension||wrist extensors: extensor carpi ulnaris, extensor carpi radialis, extensor digitorum longus,|
|pronation||pronator teres, pronator quadratus, Brachoradialis (from a supinated position)|
|supination||supinator, brachoradialis(in pronated position)|
|radial devation||flexor carpi radialis, extensor carpi radialis|
|ulnar deviation||flexor carpi ulnaris, extensor carpi ulnaris|
|Thumb: (first carpo-metacarpal and metacarpo-phalangeal joints)||flexion||flexor pollicis longus, flexor pollicis brevis,|
|opposition||opponens pollicis, opponens digiti minimi|
|abduction||abductor pollicis brevis|
|fingers (metacarpo-phalangeal joints, proximal and distal interphalangeal joints)||flexion||flexor digitorum muscles, (tendons)|
|extension||extensor digitorum muscles (tendons)|
|adduction||palmar interosseous muscles|
|abduction||dorsal interosseous muscles|