An Oldie but Goodie

This was Time Magazine’s Cover Photo from a 2009 article written by John Cloud. One of my favorite, most controversial fitness covers I’ve seen in years. Brought to me by one of  my clients, man what a good article. It’s a message that has gotten louder over the last few years: exercise doesn't work for weight loss. There was The Myth about Exercise featuring a photo of a woman pounding a treadmill, her eyes focused on a yummy looking cupcake. It symbolized the story’s thrust: research suggesting exercise won’t help weight loss because it makes us eat more to make up for the calories we burn. It’s a message repeated recently in the new book Big Fat Lies in which author David Gillespie – a lawyer – describes exercise for weight loss as ‘pointless’. But is it really true? No, says David Driscoll – not a lawyer, but an exercise physiologist and sports dietitian – who thinks that exercise deniers, like climate change deniers, don’t tell the whole story – they cherry-pick the evidence that suits their message instead. It’s not hard to find research showing exercise does shift weight, especially when it’s combined with a leaner diet, says Driscoll, a member of Sports Dietitians Australia. But when studies do find little or no weight loss benefit from exercise, this may have more to do with behavior than biology. 

 “Can Exercise make us eat more? – YES – what’s not clear is whether this is because our bodies are demanding the extra fuel or because we think we deserve it,” he says. “In studies where people do consume more calories after exercise no one’s asked them if it’s because of real hunger or because they feel they need a reward for working out. We need to establish this – it’s well-known that eating isn’t always related to hunger. When research finds little weight loss from exercise, Driscoll believes it’s also important to look at how much fat is shed, not just weight. In some studies people may not lose much weight but they may lose fat and gain muscle.

As for a shining example that diet and exercise do work, there’s the U.S. , a project tracking the progress of 10,000 people who’ve lost an average of 65 lbs and kept it off for over five years – and guess what? Ninety eight per cent of these successful weight loss losers report that they changed their diet in some way to lose weight – and 94 per cent increased their physical activity.

So is the exercise-is-useless message a dangerous one?

It’s irresponsible, but it’s also a message that some people want to hear and it appeals to people who don’t like exercise. But I don’t think it will make people who are already exercising stop. Driscoll says – “And in the unlikely event that exercise turned out not to work and actually caused weight gain, the health benefits of physical activity are so great they’d offset the problem of a little extra weight gain.”