Are you sitting too long?
by Claire Powell Chartered Physiotherapist
Current UK exercise guidelines recommend that adults take at least 150 minutes (2.5 hours) of moderate to vigorous intensity physical activity each week, aiming to be active every day. However, it has been estimated that in Western countries 75% of work is now performed sitting and modern lifestyles are becoming more sedentary.
Many office jobs require long hours of sustained sitting, which is a position of spinal flexion. More people are sitting on the way to and from work, spend most of their working day sitting, and then relax in the evening slumped on the sofa. For instance, about 87% of Australians over 15 watch an average of more than 3 hours of television each day. Thus activities of sustained spinal flexion dominate many peoples’ every-day lives.
When soft tissues are exposed to sustained loading in a single direction, like when sitting long periods, a phenomenon known as ‘creep’ occurs. This slight movement in the tissues results from rearrangement of collagen fibres and water being squeezed from the soft tissue. If the sustained loading is not excessive the soft tissues recover reasonably quickly, for example if you stand up after 15–20 minutes of sitting.
However, loading with limited interruption and frequent repetition, despite the fact that these are normal loads, can alter the mechanical properties of the soft tissues. Thus despite no obvious trauma, these tissues become susceptible to fatigue failure, and the gradual development of musculoskeletal symptoms e.g. lower back pain.
For these reasons, it is important to change your posture regularly and avoid sitting for long periods of time. Try getting up or changing posture every hour for at least 2 minutes. Moving and stretching on a regular basis will keep your joints, ligaments and muscles healthier, which in turn should make you more comfortable and productive.
If your occupation requires you to sit for long periods, here are some guidelines to make sure your sitting position causes the least amount of stress on the spine, shoulders and neck.
