I have recently read a wonderful short article at New Scientist: http://www.newscientist.com/special/get-physical-nine-facts-about-fitness
DOES an activity have to get you out of breath to count as exercise? Do you really have to do half-an-hour a day? Is pumping iron a good way to keep your heart healthy? These are just some of the dilemmas many of us face when working out the best way to get fit. The good news is scientists do broadly agree on the best ways to get fit, they just haven’t been very good at telling us what they’ve discovered
One of the most striking part was: Can you be fat and fit?
In a study published in 2007 Blair recruited 2600 people of varying weight and timed how long they could run on a treadmill before becoming exhausted, a proxy for fitness (JAMA, vol 298, p 2507). Among those who were mildly obese, only a third met a common definition of being physically unfit, and only half of those who were moderately obese were unfit. Blair points out that measures of aerobic fitness – the body’s ability to deliver oxygen to the muscles – have nothing to do with the amount of fat tissue present.
In the 12 years during which the subjects were followed, Blair’s study found that the risk of dying was more closely linked to fitness than fatness. People who were fit but obese had a lower risk of dying than people who were unfit but of normal weight. That’s important, says Blair, because while many overweight people find it hard to get slim, they could still become healthier with more exercise. It’s a point he would like doctors to bear in mind when advising overweight patients.
I think this provides yet another reason for me to keep on running 😉