Jockology: How long does it take to get fit?

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The latest Jockology column is now up on the Globe website:

The question

How long does it take to get “fit?”

The answer

The pair of “before and after” pictures is a staple of fitness hucksterism. Follow our patented program for a few weeks or months, the ads say, and your body will be transformed.

Intrigued by such ads, Megan Anderson and her colleagues at the University of Wisconsin-La Crosse put 25 subjects through an intense six-week exercise program, modelled on claims made by companies such as Bowflex and Body-for-LIFE, in a 2004 study published in the Journal of Strength & Conditioning Research. The subjects’ before-and-after attractiveness was rated by a panel of six judges, who were unable to detect any change whatsoever.

Does that mean six weeks isn’t long enough to reshape your body? Not necessarily.

“The ‘time course’ of fitness changes depends on the training stimulus: intensity, duration and frequency,” says Friederike Scharhag-Rosenberger, a researcher at the University of Potsdam in Germany who published a study on the topic in Medicine & Science in Sports & Exercise earlier this year.

Under the right circumstances, six weeks may be enough. But even if it takes longer, the benefits of exercise start long before you begin to bulk up or run faster.

Here’s what you can expect from different kinds of workouts… [read on here]