2 million years ago early humans evolved skeletons that supported their bodies in an upright position, helping us to run, fight, and throw; adaptations that enabled us to cover greater distances, hunt larger animals, and free our hands to carry tools and weapons.
While our postural evolution saw us become the dominant species, modern life is working against it. We continue to develop ways to avoid moving at all.
But contrary to common belief, poor posture itself is rarely the cause of pain or injury. In fact a recent study suggested that females with a more relaxed (slumped) posture were more protected from neck pain compared to those adopting a more upright posture. The study has some limitations, but what could be going on?
All animals – including humans – tend to operate in a way that optimises for energy efficiency. Our nature is to move and eat as much as we need. Historically those needs saw us move far more than we do today in order to secure our food, water and shelter.
‘Exercise’ is a relatively modern invention, with its development correlating with the Agricultural and Industrial Revolutions of the 18th and 19th centuries. Food became more abundant, and machines helped us to conserve energy and commit less time to labour. Simply, we ate more and moved less. ‘Exercise’ may have developed as a mechanism to help restore energy balance.
How does that relate to posture? Less energy is used when we use passive restraints (e.g. Ligaments) to maintain sustained positions. We do this when sitting slumped. In contrast, holding an upright posture for sustained periods requires muscles to work. When held for too long these muscles fatigue, setting off a cascade of chemical events that can lead to pain or ‘tightness’.
So rather than expending energy to hold sustained upright postures, humans tend to slouch when they sit. It doesn’t look nice, but it probably isn’t as harmful as we think. It seems far better to vary our movement and adopt a variety of different postures than try to sustain a single ‘ideal posture’.
As people restructure their work/home balance, many are reducing their commute and moving less as a result. Our cultural evolution over the past century has seen us become more sedentary. The pandemic has magnified it. So, it is important to remember what our bodies have evolved to do. Lift, walk, climb, run, throw, dance.