Many people consider lifting heavy weights or running and riding kilometres the catalyst for a long life in the quest for greater fitness and health, but three often ignored elements may hold the key to greater longevity than many other factors as we age. These are stability, flexibility, and mobility. What are they, and what value do they hold?
Stability
Usually, stability is defined as ‘a state of being solid, immovable, and capable of returning to a position after disturbance.’ Fundamentally, it is our capacity to maintain a stable position and rectify ourselves if we lose that point.
The biomechanical aspects that occur when our body needs to stabilise itself in a situation are a combination of our sensory (neurological or central nervous system) pathways, our muscles (skeletal), and some small endocrine (hormonal) influences.
Imagine you have been out for a walk and stepped on an uneven surface, which causes you to falter.
The pathways to becoming stable again are as follows: A sensory nerve in our ankle or foot tendons or ligaments (afferent nerve) senses that there has been a disturbance. A sensory message travels along that nerve to the spinal cord, which travels to the relevant part of the brain.
The brain then interprets what is needed in response. A message is sent from the brain through the spinal cord and nerves (efferent nerves for muscles are called somatic nerves) to turn some muscles on at a specific level of force and others to relax to become stable again.
To explain, a ligament joins bones to other bones, whilst tendons join muscles to attachment points on bones. Factors affecting the explained process include surgery, where a ligament has been replaced with artificial material. Consequently, our body might not have a nerve to that artificial component, meaning we are at risk of further damage.
Improving stability in the lower body can be as simple as standing on one leg. Another is standing with one leg lifted so your thigh is parallel to the ground (without leaning forward at the waist).
You then try to lift the heel of the leg you are standing on off the ground and balance on the front half of your foot. This is a real challenge.
For the upper body, just sitting for a few minutes on a fit ball or yoga ball will help the torso. An advanced version is to sit upright on the ball, then try lifting one leg without leaning to one side or another.
Specifically for the arms and shoulders, kneel on all fours on a stable surface, then place a piece of thick foam or an air cushion under one hand.
Lift the other hand slightly off the ground to cause the hand on the cushion to oscillate.
Flexibility
Most people interpret flexibility as moving all their body parts through their optimal range of motion. More specifically, it is the ability of our muscles to lengthen and then return to their normal length with the least amount of resistance. Biomechanically, muscle flexibility is essential for moving freely and reducing unnecessary forces on other muscles (and joints).
An example of having an inflexible muscle and its effects is tight hamstrings, which can cause long-term pressure on the lower back and increase the risk of falls.
Our hamstrings cross over the back of our knees and run up and onto the rear of our pelvis. When tight, they can pull the bottom of our pelvis forward slightly (called posterior tilt), flattening out our lower (lumbar) spine.
Over time, this then places excess force on the front of our cushioning discs (intervertebral discs), leading to bulges onto nerves and, in some cases, pain.
Tight hamstrings will also restrict our ability to lift our knees upwards, for example, when we walk, increasing the chance of catching our feet on objects and falling.
There are multiple theories on how long to hold a stretch and how long is enough to improve muscle flexibility. One thing is sure for most of us, the less you are stretching, the tighter you become. A quick tip for improving flexibility is to know what muscles you are trying to stretch that are tight – generic stretches are not the best.
Most of us are best off getting professional advice on the most effective method to suit us as individuals.
Mobility and our bodies
Mobility is often confused with a generalised version that we are ‘mobile’ in life, meaning we can get around doing day-to-day tasks reasonably unhampered.
In the biomechanics world, mobility usually means that we can move a specific joint through what is referred to as its normal range of motion.
Moving a joint through its normal range can decrease general wear and enable us to move safely and comfortably the way our joint is meant to.
Mobility can be improved in a joint, usually without the targeted joint being under a load or pressure. Simple examples for a knee are lifting the foot off the ground and swinging the lower leg back and forth, or for the joints in the hands, place two marbles on a plate or flat surface, then try rolling them in one direction and then the opposite.
The shape of our skeleton from birth, bone damage that may not have healed in its original position, and some diseases (for example, osteoporosis or calcification in the spine) can influence the quality of our joint mobility. Knowing the joint you are targeting is also essential to what you are trying to do.
Three elements merged
Stability, flexibility, and mobility can be imagined together if you walked and stumbled forward over an object.
You have suddenly become unstable on one leg, so the body sends messages which return with an action to step forward (trying to stabilise).
If the muscles in our legs, hips and lower back can move well to their full length (flexibility), we can step long and catch ourselves, and our joints (for example, the knee) can swing high and out enough (mobility) under the control of our muscles to help our front leg catch the fall.
Losing these elements has been proven to increase the risk of falls and reduce our ability to maintain independence.
As we age and our bodies’ physical priorities change, maintaining stability, flexibility, and mobility will essentially provide invaluable input into our continued quality of life.
Related issues are the importance of maintaining quality muscle in our bodies, its relationship to good mental and physical health, and its role in helping facilitate greater efficacy when fighting cancer.
David Hoffmann
MExerMed (Oncology), BSpExSc.
