October 2011
In late September, many Valley residents joined other happy walkers from further afield in the Trek for Timor. We set out in a delightfully cool light mist, with some opting to stop after the enjoyable 14 kilometre walk to Fitzroy Falls and others of us battling on for the full 50 km.
I suspect I was the oldest woman to complete the 50km, although I must admit I had to push myself a bit for the last 12 kilometres when various ‘bits’ of the body started to complain!
No one needs to walk 50 km in a day for health reasons, but something more moderate is important.
A growing body of evidence shows that physical activity is not only beneficial for us, but essential for good health. By contrast, no research has shown that we should spend more time in sedentary pastimes.
With two-thirds of men and more than half of all women in Australia now overweight or obese, physical activity deserves more attention. Being active not only helps control weight, but it substantially reduces the risk of type 2 diabetes, heart disease, some types of cancer (especially bowel cancer), osteoporosis, mental health problems and dementia. Any pill that did even a fraction as much would be hailed as a miracle!
My own interest in physical activity and health has centred on two factors: prevention of excess body fat and the increased blood flow that delivers a better balance of nutrients to improve general health. More recently (and no doubt likely to grow stronger with age), my interest is increasing in the value of physical activity in reducing the risk of dementia.
‘Reducing risk’ is not absolute. We cannot give an ironclad guarantee of total protection, but when we look at studies involving hundreds of thousands of people, those with increased physical activity have far greater chance of a long and healthy life.
I’m sure we’ve all heard (or known) someone who eats appallingly, smokes, drinks too much, has no exercise and lived to 95! Such people exist, although they are rare. They may have luck and ‘good’ genes on their side, but the fact that the odd person gets away with risky behaviour doesn’t make that behaviour a good idea.
Some people cross the road without looking and get safely to the other side. But it would be silly to tell children (or adults) that it’s OK to run out onto the road any time you like because someone did that all his life and lived to be 95! So why do we use this argument when it comes to eating, drinking and doing no exercise?
Simple actions to reduce risk seem sensible to me and the ‘action’ doesn’t need to be as extreme as walking 50 km in a day. It just needs to be something other than sitting down for many of our waking hours.
Physical activity burns kilojoules. The numbers don’t look good on paper – for example, it takes several hours of walking at 5 km/hr to burn off the energy from a burger and fries. But the kilojoules burned do add up for every bit of activity and so it does count. For those who are heavier to start with, the good news is that any activity you do will burn more kilojoules than occurs with lighter people.
Even more important than burning off kilojoules, however, is the fact that those who are physically active improve their appetite control. One of the major reasons so many people eat more than they need is because the appetite control mechanism goes haywire without physical activity.
Ironically, we often misjudge ‘busyness’ for physical activity. Being busy is a major reason so many people are less active. Being busy often means we have no time to walk or play sport. How busy do we really need to be?
For those who are not overweight, physical activity also means you can eat more and stay slim. Our daily lives used to involve lots of physical activity, but most of us now need to consciously take time for activity.
What is even better news – the brain works better after physical activity. Studies in South Australia found that when schools programmed an hour of physical activity into every school day, the students got through more schoolwork in their remaining hours than students in similar schools without the activity program.
For adults, physical activity also changes the way the body uses glucose from the carbohydrates we eat. If we are not active, a high intake of carbohydrate-rich foods can mean some blood glucose is converted to fat. When we are active, this carbohydrate is converted to glycogen which powers the muscles and allows us to be more active without feeling tired.
Our sedentary lifestyle has led to a rapid increase in type 2 diabetes, which makes up almost 90% of all diabetes and is the fastest growing health problem threatening Australians (and our future health budget).
The Australian Bureau of Statistics has just released data showing type 2 diabetes affected 3.3% of the population in 2007-8, up from 1.1% in 1995. Diabetes triples the risk of heart disease and increases problems with kidneys, eyes and nerve fibres (neuropathy). The latter can cause weakness in the arms and legs or problems in the digestive tract, the heart or blood flow to sexual organs. Many cases of type 2 diabetes would never occur if we were fitter and thinner.
To return to where I started, now would be a good time to commit to the 2013 Trek for Timor. The full 50km takes a lot of work, but the first 14km to Fitzroy Falls passes through such a wonderful part of our Valley, and every walker I saw arriving there looked happy!