If you're sick of hearing bad news about ageing and physical decline, here's some good news. Not long ago, researchers at Saskatchewan's University of Regina took a group of men aged 60 to 70 and gave them a 22-week strength training program. They then compared them to a group of 18 to 31-year-old untrained men - and found that the two groups were pretty much equal in muscle mass and strength.
'Decline is inevitable' is one of the rules, 'how fast you decline is up to you' is another. In other words, there's a choice: we can sit around grumbling about thickening waistlines and dwindling strength or we can do something about it.
This book is a good place to start. It's neither glamour fitness ('your best body in six weeks!') nor macho boot camp, but an intelligent guide to using weights like dumb bells, kettle bells or barbells, and your own body weight, to build strength and power.
Start strength training now and by your 60s you can offset some of the age related changes that can cause muscle loss, adds Rob Newton, Foundation Professor of Exercise and Sports Science at Western Australia's Edith Cowan University.
"New research has found that regular strength training causes satellite cells attached to the outside of muscle cells to proliferate and donate nuclei to muscle tissue, allowing new cells to grow. It's like inserting a self-repairing kit into the muscle," he says. "This means that by the time you're in your 60s the engine under the hood might be an old one - but it's still good and tuned for repair and growth."
Strength training also helps preserve fast twitch muscle fibres – the fibres that generate force rapidly so that you can quickly move out of harm's way or stop yourself falling if you trip.
"These fibres dwindle rapidly from the sixth decade of life but this is predominantly due to changes in behaviour like being more sedentary rather than age per se," says Newton. "Once these muscle fibres shrink and lose their nerve supply you can't regenerate them again and this compromises our function."
Research now suggests it's loss of muscle, not just gaining extra fat, that's driving many diseases, he says.
"When you have a big meal you get a surge of insulin which drives glucose into the muscle – it's like ringing a dinner bell and saying 'here's your glucose'. If a muscle is big and active it can suck this glucose up but if not, the muscle says 'sorry – can't use it' and the glucose has to go elsewhere and be stored as fat or result in chronically elevated blood sugar and type 2 diabetes."
How much strength training is enough?
"Two to three sessions weekly with each session including six to eight exercises targeting different muscle groups," Newton suggests. "The weight needs to be heavy enough that you can only lift it six to ten times in one set – and three sets of each exercise are better than two."
The New Rules of Lifting for Life by Lou Schuler and Alwyn Cosgrove is published by Avery, RRP, $29.95