Once we have bred and reared our young, what happens to us has no effect on the continuation of the species, so our later years have not been affected by any evolutionary pressure.  As a result, not only have we not evolved to have a comfortable and sprightly old age, but the quality of it is very dependent on the deliberate, conscious effort we put into it.

I was prompted to think about this because I was both concerned and puzzled.  Though I am aging with great indignity, I am in reasonable nick.  By contrast, many people I know have deteriorated conspicuously and it seems, on reflection, that the various things I have enjoyed doing through the years, having always exercised both my mind and my body, have, by lucky chance, benefited me considerably.  Others, less fortunate, have pursued activities, which amount now to a policy of self-destruction. 

I am concerned, as these individuals are good friends and their condition saddens me.  

I am puzzled because despite being intelligent and rational and well aware of their condition they seem to be monumentally reluctant to adopt a few slight and gradual changes in their lives that could yield enormous benefits.  Their attitude has the feel not merely of ‘going quietly into that dark night’, but of helping to draw the bloody curtains!

So, where, I asked, does this dreadful, potentially lethal, reluctance come from and what can be done about it?

Let me play the bad author and jump to the end.   The condition can be painlessly cured with a little determination and almost minimal effort .  That said, without this effort and determination, your condition will worsen – there is no such thing as the status quo – your so-called ‘normal’ lifestyle does not exist and cannot be preserved.  Bluntly, if you are not improving, you are deteriorating. 

Change and Conservatism
From the sub-atomic world of quantum mechanics, through the prodigious biological ferment of the human body, and out into the vastness of galactic space, nothing anywhere is still – everything is moving - change is the norm.  Yet, we humans have evolved a powerful streak of conservatism that resists this.  Why?  Because we need to be able to control it to some extent in order to gain enough security and stability to breed and rear our young.  We have sufficient adventurousness to ensure we will be adaptable enough to find and maintain this security for a while but, at heart, our resistance to change dominates.

The Problem with Conservatism
Just as there has been no evolutionary pressure to help us with old age, so there has been none to switch off our conservatism once it has served its immediate purpose of providing security for our young.  It keeps on chugging away regardless, relentlessly resisting change.

Many of the things we do – fastening shoelaces, driving, writing, eating, on and on - we do by habit.  Our bodies have evolved to learn small repeated actions and do them for us.  Not only that, we keep on improving with continued repetition – we get good at what we do. Do not confuse small with trivial – ‘little-and-often’ is a powerful, powerful mechanism.

The Problem with Habits
Our habit-forming trait is splendid but it makes no judgements.  Whatever we do regularly, bad or good – smoking, drinking, eating badly, denigrating ourselves etc – our bodies will pick it up – it will become a habit, and the more we do it, the better we will become at it.  

Which leaves us where?
In our later years, our redundant, but continuing conservatism, having been practised relentlessly every day, has become a deeply entrenched habit.  As a result, any attempt to ‘change our ways’ however slightly, meets with truly prodigious and increasing resistance.  You think not?  Even now, it’s tempting you not to read any further – (if it let you get this far!).

At the very thought of doing something ‘different’, serried ranks of excuses spring up immediately – you’re too old, too stiff, too dignified, too settled, it’s too late (!!!), blah blah, on and on.  The best you might manage is, ‘well, er, I’ll think about it - maybe next week’.  And should you manfully defy these siren calls and actually attempt anything you will find that the urge to give up is almost overwhelming .

This is a perfectly natural, even inevitable response, but see it for what it is – an old and now useless habit that will kill you prematurely.  Don’t forget, there is no status quo, no way you can ‘stay the same’.  Fortunately, there are plenty of ways in which you can improve yourself which require little effort and little time.  There is a nice irony in the fact that a slight change to your lifestyle can produce a considerable and beneficial change to your life.  

What needs to be done?
The first thing is to accept not merely the uselessness of our residual conservatism, but its potential lethality – it has outlived its usefulness and now it is killing you.  Then you need to think about what you want.  If you are content to continue deteriorating, fair enough – read no further, but think about this: at no time in your life has there been a guarantee that you will be alive in five minutes, nor has there been any to say that you won’t last for many years.  Even at say, 85, you could be alive in 15 years.  That’s a very long time - do you really want to spend it waiting to die, and constantly whingeing about your decline, or do you want to take the chance that there might be plenty of good times ahead, and even the chance to do something useful?  Your choice, your responsibility. You cannot stop yourself aging but you can avoid becoming an old person.

If you are prompted to think about this a little more, you might find the following helpful.

An Overview
Basically, we need to get things moving.  Only dead things are motionless.  When you move a joint, nerve impulses, blood, lubricants and nutrients move to it and help to keep it in good order - waggling your toes anytime, for example, is not a trivial exercise, you are sending stuff to the farthest point from your heart.  Joints that are not moved, deteriorate.  The adage, ‘use it or lose it’ is desperately accurate.  There is an analogous response within the mind to creative and problem-solving thinking.  Mind and body are intimately linked – we all know that mood affects posture, but what we are usually less keen to admit is that posture affects mood – this is very important.

Just a few words of advice before we press on.

Mental Exercise - If you have a particular unfulfilled ambition, do it, and do it now - or at least start planning it if it is something big.  If you haven’t, then do anything .  It really does not matter what.  Give it a good try and if you do not like it, do something else, and so on.  Read, write - your novel, play, epic poem, autobiography, whatever - do puzzles, play games, paint, draw, sculpt, learn to juggle, compose your opera, symphony, musical, learn an instrument, write out the rules for hopscotch in Sanskrit, run for Parliament, anything.  There are no limits here save your own imagination, just be patient and persistent – little and often will do it.

Physical Exercise – All the following can be practised at any age.
Tai chi and qiqong (chi kung) exercises .  Subtle and quite amazing.  If you do nothing else, do these!  Gentle co-ordinated movements surreptitiously improve balance, posture, breathing, flexibility, co-ordination, and overall physiological (mind and body) efficiency.  You can do many of the exercises sitting down if you are particularly frail or unsteady.  Ideally join a class, but there are plenty good books and a lot on the internet.  Don’t do more than 5 minutes a day at first and, if possible, do it outside.
Cardio-vascular training to improve the efficiency of your heart, lungs and circulation - your stamina.  You may well not have done any exercise for decades, so take this very steadily.  Here is one way: every day - dress appropriately for the weather – walk for half a minute, turn round and come back.  Next week, maybe walk for a minute, then maybe a minute and a half and so on.  Once the habit is established and you are doing all you want – say 4 minutes out and 4 back – stride out for a few paces.  Build this gradually until you are striding all the way then maybe trot for four paces etc etc.  Remember – set no targets.  As important as the exercise itself is the changing of the old habits. 
Resistance training to help prevent loss of muscle mass and bone density.  This is the hardest of the three forms of exercise as you will need to join a gym to get proper instruction and equipment.  It is also perhaps the least important, but it is very worthwhile and you may well be surprised at the age of some of the people you find yourself training alongside.

Some Tips
Learning tai chi.
Most of us find learning physical moves quite difficult.  Do not try to learn more than one move with each class.  When you get back home, do that move immediately – don’t take your coat off, put the kettle on etc – just do the move.  That way you are far more likely to remember it.

Can’t .
Tear this suffocating, dreadful, word from your vocabulary.  Your mind and your body are so intimately linked that just thinking you cannot do something provokes a physical response that makes it so – a classic self-fulfilling prophesy.  By all means admit that something is difficult because nothing worth doing is easy - but "can't" - never

Doing it right .
When, after endless repetition of something you eventually do it ‘right’, lock that into your mind, even if the skill slips away from you almost immediately.  You did it, therefore you can do it – this is hard data now, not open to debate - the rest is practice and patience.

Parkinson’s Law – work expands to fill the time available for its completion – applies to us at any age, so when you end up with not much to do and plenty of time to do it in, things can get pretty sluggish.  I found a small timer useful for dealing with this - one which you can set to bleep after a specified interval.  So if you have, say, 5 minutes to spare, set your timer and get on with whatever it is you want to do.  You can absorb yourself completely now - the timer will tell you when time is up, at which point you can either stop and turn to your next subject or, if engrossed, set it again and do some more.  
Obsessive?  Not remotely.  It is liberating.  It enables you to use chunks of time which would otherwise dribble pointlessly away.  Further, it is time spent at your best concentration.  This is particularly valuable, for example, when practising a musical instrument where initial concentration tends to be quite intense and falls off quickly without your noticing - two sessions of 5 minutes are far better than one of 15 minutes.

Bad Luck
All of the above will improve your quality of life radically but it will not, of course, prevent you from being struck down – either by a lorry or some dismal illness. It will however, improve the odds in your favour, and make you better able to deal with the consequences.

Just as a matter of interest
The human body consists of some 10^13 cells – ten million million – ten billion.  That is a big number - 10^13 millimetres is 12 round trips to the moon!  
The majority of these cells are in a permanent frenzy of highly complex, barely understood, chemical changes - repairing things, making things, destroying things, issuing instructions to one another- and the whole is organized into countless hierarchies of highly interdependent and dynamically balanced systems.
The brain oversees much of all this with its 10^11 neurons and 10^15 synaptic connections.
Oh, and don’t forget the 10^14 tiny life-forms of one kind or another, that we have in and on us, each pottering about pursuing its own particular destiny for our benefit.
The monkey suits we walk around in have been evolved over millions of years, with millions of prototypes having been tested to destruction to make each of us, quite unhindered by any ethical concerns or health and safety claptrap.  They are impressive and they are designed to survive.  So give yours a chance.  Let that evolutionary ‘Johnny come lately’ – your conscious mind – take charge and set you on a better way forward.
Good luck.