Sitting posture is something that get’s heavily criticised and over analysed. There could be more to it than simple ergonomics.
Your best posture is your next posture
In the last several years sitting posture has been classed as the “new smoking” or a dangerous position that will ruin your life. There are various arguments for and against sitting from different health experts and research. My opinion on this topic comes from my own clinical experience and taking value from all of the other respective parties.
First of all, sitting is not dangerous. But the longer we sit over a prolonged time is not healthy
Our body is dynamic and multi-functional, one of these functions is sitting. What’s up for debate is length of time and position. Recent studies have documented the following long term health risks from prolonged sitting.
**These studies are predictors for potential health risks, but are also contributed by poor nutrition, sleep deprivation and lack of exercise.
What’s the physical problem with sitting?
In unsupported sitting (i.e. on the floor, perched sitting) we have some activity from core muscles that stabilise the spine. With no activity we would collapse into a heap.
Our central nervous system cleverly adapts to positions we hold most in the day. In supported sitting our body adjusts, slowly loosing flexibility in the thoracic spine, hips and hamstrings. The trunk muscles, “the core” reduce activity in sitting and loose their primary function of support when doing physical activities. Other muscles like the glutes, scapular stabilisers and posterior rotator cuff become short or weakened.
With the lack of support our body naturally falls into the path of least resistance and this is when changes in posture begin to happen. Essentially causing us to hang off the tension of ligaments and other soft tissue, instead of support from the tone and strength of stabilising muscles.
Chemical changes are brewing while sitting
The longer we sit without movement puts more stress and pressure specific tissues. Causing reduced blood flow to that area, meaning it gets less oxygen and less removal of metabolic bi-products. The muscle becomes increasingly toxic and acidic.
Luckily our tissues hold acidic sensing Ion channels that detect changes to PH levels. When in an acidic environment it sends our brain a signal and we get the feeling of discomfort.
Choosing to ignore the discomfort and stay in the same position causes an increase in toxicity and will result in the development of the trigger point phenomenon. Another phenomenon called central sensitisation may also happen. When pain signals constantly bombard the brain with pain signals it lowers your pain thresh-hold, making you more susceptible to pain in stressful environments.
Whats the answer to sitting?
Looking at the physical and chemical changes that happen in a sustained position you can see that any position for a prolonged time is not beneficial to us.
A posture that doesn’t move isn’t a postural problem, it’s a problem of movement.
“Neutral” spinal and postural alignment is all well and said. But even sitting in an ergonomically aligned position will feel uncomfortable if sat this way for 8 hours.
To counteract the negative effects of sustained sitting positions, here are some recommendations:
1. Position variation
Look at the postures below. Some of them were traditionally classed as “bad” postures. But these postures vary the tensions and stress’s applied to different tissue. By regularly changing these forces it will allow you to tolerate sitting for longer. Making a conscious effort to change position every 15-20 minutes (remember you can still work, just change position).
2. Get up and move
Offload the stress and compression of your toxic butt! Giving a chance for tissue to oxygenate and flush unwanted toxins away. Also reducing eye strain, stress levels and fatigue. Not to mention all the other long term health benefits displayed above.
Studies have shown improvements in performance with intermittent breaks every 30 minutes (4). Consider standing when taking a phone call. Think about how many calls you get a day!
3. Sit-standing desks
Standing desks have taken off and are all the rage in open plan offices. Standing gives those stablising muscles a chance to work their magic. But even with standing you should consider regularly changing standing positions to offload pressures. Using a perching stool or foot stool to alternate step-standing.
If this component is not included all of the above strategies will be wasted. Standing desks are not an exercise, it encourages a little more activity and is more sustainable. But your body needs to be challenged in other positions other than the one you hold most of the day. The long term health benefits are well documented for exercise.
Remember if you are just starting to exercise and coming from prolonged sitting over a number of years, ease into exercise gradually. Start off with regular power walks or exercycle. But as your fitness improves try to challenge it more, through other sources like pilates, yoga, resistance training or team sports.
Sitting isn’t the problem, it’s not moving enough.
- Bell et al, (2014) Combined effect of physical activity and leisure time sitting on long-term risk of incident obesity and metabolic risk factor clustering. Diabetologia
Schmid et al, (2014) Sedentary behavior increases the risk of certain cancers. J Natl Cancer Inst
- Sedentary behaviour and life expectancy in the USA: a cause-deleted life table analysis.
- Thorp et al (2014), Breaking up workplace sitting time with intermittent standing bouts improves fatigue and musculoskeletal discomfort in overweight/obese office workers. Occup Environ Med.