OPINION: A saying often used by fitness gurus is: "If you think exercise takes too much of your time, try having a heart attack".
We frequently hear that exercise is the key to a happier, healthier, longer life. Recent research proves this is true and provides an intriguing reason why.
A German television documentary called Escaping Illness recently examined the benefits of exercise; some of the issues it addressed are summarised in what follows.
It should be no surprise that exercise is good for us. After all, our bodies evolved to be capable of tracking and chasing our food over long distances. In the animal kingdom, according to Professor Klaus Michael Braumann of Hamburg University, humans are the gold medal winners for endurance. There are African tribes that literally track and follow their prey to death.
It is a reasonable assumption that modern living with its avoidance of exercise is going to result in health issues. Typically, we move from A to B in our cars, sit at office desks all day and lounge about in the evening. Lack of exercise is a huge contributor to heart attacks, diabetes, neurological disorders and inflammation related diseases.
Each of us should be burning 8400 joules of energy per day in exercise alone. That is equivalent to three hours a week of gentle jogging or four hours a week walking. Inactivity is a killer because energy reserves accumulate and fat cells are then distributed throughout the body.
Bigger, stronger muscles produce anti-inflammatory substances and it is known that inflammation plays a significant role in a wide range of diseases. Big muscles mean more blood vessels which are the highways to transport energy to the consumers. The more blood vessels, the more efficient is the disposal of energy. Regular exercise is also good for ensuring the joints and organs function properly.
Two-thirds of people over 60 have to stop whilst walking up three storeys of stairs. A hundred years ago the average person walked about 20 kilometres per day. Compare that with the largely sedentary lifestyle of most people today who on average walk only 1km a day.
Exercise increases the heart's ability to pump blood, achieving results unattainable through medicines. Professor Marion Kiechle from a women's clinic in Munich says that diet and exercise play a crucial role in determining the probability of relapse of cancer in her patients.
Her study showed that diet reduces the probability of relapse by one-third and exercise reduces the probability by a half. So compelling are the results of this research that many German hospitals even coax weak, immediate post operation cancer patients onto treadmills for gentle walking exercise.
Clues as to why exercise is so good for you were reported earlier this year in The Economist. Beth Levine of the University of Texas in an article in the prestigious journal Nature reported that she had demonstrated "autophagy" is the key. This is the mechanism by which surplus and worn out proteins and other cellular components are broken up for scrap and recycled.
Autophagy evolved to help the body survive when nutrients were scarce. Autophagosomes are molecules that assist in the breaking-up and recycling process. Dr Levine showed that exercising laboratory mice on a treadmill increased the number of autophagosomes in their muscles.
Significantly, autophagosomes also increased the uptake of sugar from their bloodstream (a key symptom of diabetes is high blood sugar levels).
Many studies report that near starvation diets can increase lifespan. Such diets stress the cells and cause the production of autophagosomes. The theory is that these molecules destroy the mitochondria of cells; mitochondria are the cells' power stations.
In the mitochondrion, glucose and oxygen react producing energy, but this process also generates free radicals which play a key role in disrupting DNA and hence accelerating the ageing process. This includes the disruption of neurological processes (leading to dementia and the like). The good news is that regular, mild exercise has a similar effect to stringent dieting.
The moral of this tale is that a little exercise goes a long way. If you have a medical condition then consult your doctor before exercising.
For anyone not used to exercising there are a few golden rules to follow: Don't be over ambitious; stick to within your limits, and get into an exercise habit. You'll be hugely rewarded by feeling much healthier and happier.
There is no excuse to avoid doing regular exercise. After all, a heart attack is so much more inconvenient.
- © Fairfax NZ News
What's your view of sand mining?Related story: Environmental group urges mining fight
with Rachel Stewart
Matt Rilkoff's perspective of contemporary life
with Gordon Brown
With Kathryn Calvert
The self-confessed bard of Brixton, offers views on life, politics and Akubra hats.
with Glenn McLean