Retain Normal Shape
The normal curve of the lumbar vertebrae is straightened out when we bend forwards. If we work in a forward-leaning posture our lumbar musculature cannot work as it should, the vertebrae are pressed together at the front and the ligaments at the back are stretched out. At the same time pressure on the discs is spread unevenly. Everyone has at some time experienced slight aching, stabbing pain or feeling of tiredness in the lumbar region after standing in such a position. The problem receeds if we move into a position where the body’s natural S-shape is restored.
Occasional standing or sitting bent forward will cause no damage, but if it is repeated over an extended period, problems can result in the long-term. Therefore we should strive as far as possible to retain the body’s normal shape during all work, both sitting and standing.The back has many small joints. How they move thebvertebrae determines the flexibility in the different parts of thebback.
Joints create an enclosed space as they are surrounded by a joint capsule. Within the capsule, the joint surfaces are covered with a layer of cartilage which is strongest in the middle and thinner towards the edges.
The idea is that the joint is principally loaded where the cartilage is thickest.
If pressure is put on these joints from an angle, for example by lifting crookedly or bending and turning at the same time, we can over a long period of time, put joints under extreme strain. This is because the joints are being loaded where the cartilage is thinnest and most brittle rather than where it is thickest. There is a clear risk of injury.
Therefore avoid all lifting where you bend and turn the body, as these movements are harmful.