If you know anything about fitness you may probably already realise the effect exercise has on your body in terms of helping you burn calories even after you've finished your work-out. But a new study shows the effect can last for a surprising 14 hours if you really go for it.
After-run calorie-burn: is that Reese Witherspoon's secret? Photo: Greenpix/bauergriffinonline.com
According to exercise physiologists at the University of South Australia, whose study has just been published in the journal Medicine & Science in Sports & Exercise, an intense 45-minute workout not only helps you burn loads of calories while you're exercising, but you could continue to burn calories for a further 14 hours afterwards.
That's what we call a result. The study was, however, carried out with male volunteers, aged between 22 and 33, who had varying levels of fitness. They had to work out on a gym machine called a cycle ergometer, and burned an average of 519 calories in 45 minutes - which is pretty good going.
And on average, they burned an extra 190 calories during the 14 hours after their workout (that's in addition to the calories they would normally burn during that time).
The problem is you have to really push it to see those kinds of results - and of course, there's no real evidence the same would apply to women (though we don't see any reason why it shouldn't).
While we're on the subject of exercise, a separate study by US fitness experts claims stretching before a run doesn't stop you pulling a muscle or having any other type of injury.
Will you be going for a run this weekend, or is a lie-in more your style?