Imagine this scenario. You work out a couple of times a week, you walk more than you take the car and you play the odd game of squash or tennis.
And you feel great - lively, focused and full of vim.
Despite that, your weight remains stubbornly one, two or even three stone higher than you'd like it to be. Your BMI (Body Mass Index) is in the 'overweight' category and doctors say you need to slim down. They say your weight increases your chances of getting a range of nasties, from diabetes and heart disease to various cancers.
If that sounds a bit like you, you're certainly not alone. Plenty of men - especially in the 18 - 40 age group - exercise pretty regularly but still find themselves in the 'unhealthy' zone when they stand on the scales.
Fat and healthy?
And for that group of men, a new study, published this week, is good news indeed. Because what the research seems to indicate is that your doctor - and popular opinion - may have got it wrong. You can be both fat and as healthy as a slimmer counterpart.The study, by the University of South Carolina, looked at data from 43,000 people and found that, on its own, being overweight didn't add to your health risks. It found that obese people had the same risk of developing or dying from cardiovascular disease or cancer as people of ideal weight, provided they were 'metabolically fit'.
What is metabolic health?
And put simply, what they mean by 'metabolically' fit is that under the bonnet all is well, even if the bodywork needs a bit of loving attention.
So you're metabolically fit if you have normal cholesterol, blood sugar and blood pressure ratings. If any of these are raised, you start sliding into the metabolically unfit category.
The problem for obese people is that extra weight makes them more likely to have raised cholesterol, blood sugar and blood pressure. The British Heart Foundation says that obesity is an "undeniable risk factor" for developing coronary heart disease, because it tends to have an adverse effect on all three.
But the new research suggests one way in which overweight and obese people can overcome this added risk. Quite simply, they can exercise.
What does exercise do?
In a nutshell, the research found that a subset of obese people didn't suffer from raised blood pressure, blood sugar or cholesterol, and they were the ones that exercised. The study suggests that overweight people who want to limit their chances of contracting a range of diseases should concentrate more on getting fit, and less on getting thin.
"This research highlights once again the important role of physical fitness as a health marker," says lead researcher Dr Francisco Ortega.
And it's not the only research that leads to this conclusion. Exercise scientist Professor Stephen Blair, also of the University of South Carolina, is one of the world's leading experts on weight and health. He agrees that overweight people are unhealthier than people of normal weight, if they're unfit.
If they're fit, he says, "the harmful effect of fat just disappears."
Not everyone agrees
It's fair to say that the latest research swings the argument towards the 'fat and fit' conclusion. You can be overweight and, as long as you exercise enough, reasonably healthy.
But it should be pointed out that other research leans in the other direction.
For example, a study on men in the Swedish city of Uppsala found that overweight men were at higher risk of heart disease than men of healthy weight, and that was despite other factors. Exercise might lower the risk for overweight people, but it was still higher than the risk for people of normal weight.
"Some researchers have suggested that a heavy person without other risk factors didn't need to lose weight," said lead Swedish researcher Dr Johan Arnlov. "Our data does not support this notion."
Can you really be fat and fit?
So it's impossible to draw a definitive conclusion on the 'fat and fit' debate - yet. But the latest study does add to a growing body of evidence suggesting that, if you're carrying a few pounds - or a few stone - too many, you should get off the scales and into the park.
The study proves that it's at least possible to be fat and 'metabolically' fit, so whatever your weight, it seems that taking exercise is one of the surest ways to give your health a boost.