No stage of life has a worse reputation than middle age. There might be some very good reasons for that, writes Shane Gilchrist.
What do model Naomi Campbell and actor Daniel Craig have in common with me and more than a million other New Zealanders? Okay, maybe it is easier to point out what we don't share. But the fact is, we're all middle-aged. Campbell is 40, with the body of a 20-year-old (her mood is another issue entirely). Craig is 42, with the body of a 20-year-old and a swagger to match. While that might appear to put the middle-aged in good company, some of the accompanying data surrounding the middle years is less comforting. At 41, I am between the pair and possess the body of a ... hmmm. (When last I checked, my wife's Wii Fit coolly suggested a 53-year-old physique. At this juncture, it's perhaps best to deflect any deficiencies by mentioning the results of a United States-Norway joint study, which found middle-aged men to be, well, good at sex. Then again, such proficiency is a bit like integrity - it's an external assessment, one cannot bestow it upon oneself).
As for my fellow middle-agers, Campbell seems to be struggling with her memory these days - if the recent blood diamond hearings were anything to go by - while the trajectory of Craig's stellar career has perhaps flattened with the news that financial troubles at MGM studio have put his next appearance as James Bond on hold.
But that's all by the by. The point is, many of us are middle-aged, defined in the Collins Dictionary as "the period of life between youth and old age, usually between the ages of 40 and 60". As of June this year, New Zealanders aged between 40 and 64 numbered 1.4 million, comprising 32 per cent of the population, up 3 per cent on the previous decade.
We're on the rise then, doubtless aided by the gradual increase in the nation's life expectancy, driven by improved quality of life, healthcare and nutrition. Indeed, by 2021 the median age for the country is projected to be 40, and by 2061 it could be 43.5. We're on course to become a nation of the middle-aged. Although at that point, an out clause might be in the offing. It would be arguable that the definition of middle age should be adjusted, perhaps pushed back a few years.
Perhaps. But there are only so many things you can cover up by tweaking the entry criteria.
There is a point in life when, like it or not, the body slows down, when we step beyond the threshold of maximum physical potential.
Take a look at those who hold world records, Olympic-bests and so forth, says Phil Sheard, a senior lecturer in physiology at the University of Otago's School of Medicine. "Professional sportspeople, those who make a living from their physical performance are, in general, between 20 and 35 years of age. Beyond 35 it is very difficult, in most sports, for a professional athlete to compete with people who are 10 or 15 years younger.
"That is not usually because of lack of skill, motivation or initiative. It is because their physical performance is not up to the required standard anymore. What is true of elite athletes is true of most people at large. Pretty much beyond the age of 40, we do experience a decline in our physical potential."
Though Sheard points out there are inconsistencies in the literature on the subject, it is estimated we lose nerve cells and muscle fibres from about 40 onwards.
"Some aspect of ageing - which we don't yet understand - results in the progressive loss of cells in the brain, the nervous system and in muscles that are primarily responsible for generating strength, speed, endurance and power. Some of those will die, which puts more responsibility on the cells that remain. Probably the rate of cell death increases as we get older because the responsibility falls on a progressively smaller number - the stress on them is higher and they end up dying as well. "It's not that the actions in the nervous system that dictate our activities are moving slower. Action potential is not slower, synaptic activity is not slower, but the numbers of nerve cells and muscle fibres that are doing it are progressively getting fewer."
There are ways to minimise the effects of these processes, primarily through exercise and lifestyle. Muscle, endurance, speed and strength are attributes that can be trained.
"If you are a couch potato, you are going to be weak and lack endurance," Sheard says. "If you decide to do something about it and go to the gym and lift weights you can increase your muscle mass ... It's possible to delay the onset of noticeable weakness with a modest exercise regime. Look at things like masters records for the marathon. The world record for an 80-year-old is about 65 per cent of that of the [open] world record. That's phenomenal."
Physical activity and bone density are also closely linked. Like muscle, a lack of weight-bearing exercise will weaken and demineralise bone. In regard to our brains, we possess a safety margin, a "redundancy" that Sheard likens to an engine. Though that red sports car might produce 200 horsepower, it requires only 30hp when driving around town. "What that redundancy means is that when those brain cells start dying you are losing one or two nerve cells a day or a week. Because you're rarely using 100 per cent of your capacity, if you lose 1 per cent you're never going to notice it. It is only when you lose a significant amount that it becomes limiting."
A more obvious sign of ageing can be found on the surface. Skin's texture - tight, smooth and without wrinkles (attributes on which cosmetics companies thrive) - will give someone a more youthful appearance. However, our skin's elastic tissues are constantly being stretched.
Although the sun's rays play their part, talking, laughing, frowning, closing your eyes, gaining or losing weight weaken the skin. It gets looser, allowing folds to form.
"Without being a dermatologist, my feeling would be the factors that influence the lifespan of nerve cells, like hormone status and metabolism, are going to impact on the death of the cells which produce elastic tissue," Sheard says. "I'd suggest that if nerve and muscle starts to decline between 35 and 40, our ability to make new elastic tissue is going to start declining at about the same time."
Wrinkles and the erosion of athletic prowess are not the end of it. Exposure to high-energy soundwaves, to be found anywhere from rock concerts to roadworks, damages the part of the ear responsible for high-frequency sounds, resulting in a progressive loss of efficiency - something that's likely to have taken a toll by about, oh, middle age.
Fortunately, Sheard points out, most of the sounds we need to hear, such as human speech, are at the lower end of the range.
"We can hear up to 20,000Hz, but anything over 10,000Hz is really unpleasant and you wouldn't miss it." If you are around 40 and haven't yet noticed the typeface of novels or newspapers becoming a little blurry, it's more than likely you will soon enough as you progress through a decade that could be called the age of presbyopia.
About 90 per cent of us require reading glasses by age 50 as the muscles that control lens adjustment lose their natural elasticity, meaning the lens is less able to bend light in such a way as to bring near objects into focus. At 20, we can focus on objects as close as 10-15cm; by the time we are 60, that point is closer to 60-80cm.
"All right," I hear you say. "There's only so much sobering truth any middle-aged person can face in one go." Surely there's a silver lining. An equanimity of disposition and tranquility of the soul that arrives with the grey hairs and spreading midriff.
Well, there's not much evidence for that. Rather, the research appears to be that middle age can make you miserable.
A 2008 study analysing data from 80 countries showed depression is most common among men and women in their 40s.
Researchers at Britain's University of Warwick and Dartmouth College, in the United States, analysed data on depression, anxiety levels and general mental health and well-being taken from some two million people.
They found that happiness followed a U-shaped curve: life begins cheerful enough before turning tough during middle age and then returning to a more joyful existence in later life. Although previous studies have shown that psychological wellbeing remained flat throughout life, the findings published in the journal Social Science & Medicine suggest we are in for a topsy-turvy emotional ride.
The probability of depression slowly builds and then peaks when people are in their 40s. It happens to men and women, to single and married people, to rich and poor, and to those with and without children, the researchers say.
"Only in their 50s do people emerge from this low period," one researcher said, suggesting people begin to value their own remaining years and embrace life after seeing their middle-aged peers begin to die.
Statistics New Zealand data reinforces this claim: under the heading "people who were very satisfied/satisfied with life overall" (for April 2008-March 2009), those aged between 45 and 64 were least happy.
And when we're unhappy, we go shopping. Finally there is some better news here. When it comes to money matters, the financial health of people between 40 and 60 is generally rosy, according to BNZ senior economist Craig Ebert.
This at least affords the middle-aged the ability to indulge in some denial behaviour.
"The whole concept of age groups, how people should behave, is changing. Some people I know who are in their 50s are acting like teenagers. They go off and get big motorbikes and all sorts of things," Ebert says. "They should be the sector of society with the highest earning potential. I think you see that in most surveys. The most debt loads are carried by people in their 30s, probably running into the 40s, but you'd expect by the time people are in their 50s and 60s they are wanting to pay down debt.
"There is a lot of literature about it, to do with life-cycle of income theories and what have you. A lot of it is pretty basic, actually: you start off and run up a bit of debt, then acquire a bit more debt to buy a home. The theory goes that when you get a bit more experience you can grapple your way up the greasy pole of a career and earn more money, increase savings and provide for your retirement."
Ah, retirement - riding in on its snow-white steed to deliver the middle-aged from their troubled middle years. Light at the end of the tunnel.
As the age at which we die steadily gets pushed out, so too do our chances of enjoying better health longer. Thus, 65 could be the new 55. That's a good thing, Ebert contends - though it's unclear whether it will mean an extension to middle age or more golden years.
"These people are fully able to work," he says. "These days it's not as though many of us are working down coalmines. If you use your brain - as long as it's still working - away you go.
"People are living longer, but they also have better-quality years," Ebert says. "Say someone hits 70. These days they could well be working and functioning well, whereas probably only a few decades ago those people were in nursing homes."
There you have it then. Middle age. It seems there's a good chance it is not all it is not cracked up to be.
Proponents are hard to find, though, of course, in that great unmediated ocean of rambling, the internet, there are a few. Robert L. Adams, key author of the US-based website middleage.org, has a few good words to say.
"Once we are in our 40s, 50s or 60s, we ought to think that we finally have enough experience and enough freedom to really begin to grow, not begin to decline. I know people who are 85 or older, but who still look forward to tomorrow."
Sounds a bit desperate, however.
A colleague, also a few years beyond 40, echoes those sentiments, his words suggesting middle age to be a convenient position from which one can pause and reflect on the many years gone by and, hopefully, plan for many more to come.
"In a world obsessed by a culture of youth, I rather regard middle age as the point at which the uncertainty, vicissitude and doubts of earlier years fall away, and a little clarity and even, dare we say it, wisdom begins to manifest," he says.
He may have something there. By middle age, many of us will have just about perfected the art of self-delusion.
- OTAGO DAILY TIMES