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A study has suggested that sitting up straight places unnecessary strain on your back. Instead, the best position to adopt while seated is at an angle of 135 degrees between the thigh and torso. As most people, particularly office workers, spend most of their day seated, it is important to maintain the best sitting position to minimise the occurrence of lower back pain.

Now why didn't I find this out earlier? All this while, we've been told (and struggle to practise) that the best posture is upright, and goodness knows how many times I've stuffed pillows between the 'reclining' back of various chairs I've used all my life, to create a padding to help keep my back straight. Recently, while looking for an office chair, I rejected those which had backs with a natural recline.

Here's the illustration used to describe various seating positions:-