THE EFFECTS OF REDUCED ACTIVITY
When you become unwell you may lose confidence in what your body can cope with. You feel tired, perhaps achy and sore, and the natural inclination is to rest and do less. This can also be true if you have a sedentary job or lifestyle, maybe finding yourself in one position for lengthy periods.
When you reduce your level of physical activity, for whatever reason, your body will adapt to this level of demand. Our physiology is incredibly fluid and responsive to the circumstances we create. As our body adapts we begin to FEEL weaker. Are these new sensations a result of illness-or could they be a result of these adjustments within our body?
THIS IS A HUGELY IMPORTANT DISTINCTION!
Lets have a look at what happens to a fit and active young man, if he stays in bed for three weeks. These results are based on actual observations made as part of a research project looking at the process of deconditioning:
The body ‘realises’ that it is not moving, and begins to reduce the blood flow to the arms and legs. Blood begins to circulate more in the body cavity. The limbs feel weaker and the abdomen feels more bloated.
By 8 days:
There is a reduced production of blood plasma. This is the component of the blood which carries white blood cells, and so there will be less resistance to infection.There are also fewer red blood cells produced. The red blood cells carry oxygen; therefore there will be reduced ‘aerobic capacity’. That means less oxygen is available for the muscles and so moving around will be harder.
There is therefore, less blood within the circulatory system.
By 2o days:
The heart will have become less used to pumping blood upwards, and so sitting up will cause light-headedness. This is called ‘postural hypotension’.
The heart will beat faster both at rest and when moving. The heart will have slightly decreased in size.
By 3 Days:
The muscles begin to lose strength by around 1-3% each day , causing a sensation of weakness. This weakening of the muscles will impact on the circulatory system, since the pumping action of the muscles in assisting blood flow is diminished.The postural muscles, those that help to hold us up, tend to weaken most quickly, so that it becomes more of en effort to be upright. The large thigh muscles, the Quadriceps, will weaken making it more tiring to stand.
As the muscles weaken at different rates their pulling actions on the joints become uncoordinated. This may contribute to joint pains and muscle aches.
Around day 8:
Within the muscle structure are cells called mitochondria. These cells produce the energy required for muscle contraction. By day 8 these cells begin to slightly change shape, affecting their efficiency, and reduce in number. The muscle will be functioning as if it had a flat battery.
Studies show that people who work at desks and other sedentary workers will have reduced numbers of mitochondria , compared to those with more active jobs and lifestyles.
Since all our movements require practice to maintain the responsiveness of the nerve pathway, becoming less active can cause a lack of co-ordination, particularly in fine movements.
It became harder to maintain a regular body temperature, as if our thermostat has been ‘knocked out of sync’.
It became more difficult to focus and perform memory tests.
WHAT MIGHT ALL THIS MEAN FOR YOU:
Thankfully the young man in the trial made a full recovery and returned to his previous level of fitness. The interesting consideration is that it took TEN weeks of careful training to recover from THREE weeks of bed rest!
This man was fit and healthy, and so there were no obstacles to recovery. However the effects of reduced activity apply to us all. Could SOME of what you are experiencing be a result of the same process?
Can you see how resting for EXTENDED periods cannot reduce your levels of fatigue, or help you regain strength? Ironically even though it seems counter intuitive to move, PROLONGED rest will contribute to your feeling of fatigue in the long term? It is physiologically impossible that extended rest will build stamina.
Just to be completely clear, I am not saying that if you move more you will become athletically fit and healthy. You may have a significant health issue which will compromise that process. However, could it be that you can explore ways to reach your own level of optimal fitness and health?
If it takes TEN weeks to recover from THREE weeks of bed rest in a fit and healthy young person what does that mean for you? What degree of patience and gentle determination will you need? What level of self awareness, and understanding of your health condition?
You may already see that the issues are complex, particularly as you try to build your stamina within the constraints of your health and the demands of your daily life. Never the less, it is important to contemplate the information above, and decide how it may apply to your circumstances. Then you can begin to find ways to enjoy moving and keeping fitter, not out of a negative sense of fear, but from a point of enjoyment and genuine self care.
Have a look at the video clip in the ‘what exercise can do for you’ section!