Exercise canhelp prevent weigth gain - but it wont be easy

ractayjon

By Katherine Hobson, USNews.com
There's a lot of attention paid to what works when it comes to losing weight. But that's not really the hard part; anyone can diet or exercise in the short term, but maintaining a loss, avoiding age-related weight creep, and keeping up healthful habits over time is much more difficult. That's why the researchers behind a new study, published this week in the Journal of the American Medical Association, wanted to examine the habits of people who were eating what they considered a normal diet and were "living life as usual," says one of the authors, I-Min Lee, an associate epidemiologist at Brigham and Women's Hospital in Boston and associate professor of medicine at Harvard Medical School. And they made some interesting discoveries about the power of exercise.

When researchers followed more than 34,000 non-dieting women (average age 54.2) over many years, they found that regular physical activity was associated with gaining less weight over time—but only in women who weren't overweight or obese. (That means a BMI of lower than 25, or less than 150 pounds for a 5'5" woman.) And those women had to exercise quite a bit: An average of an hour a day of moderately intense activity—such as a brisk walk—or the equivalent (if you exercise more strenuously, less time is required) during a week was the amount of activity recorded for the normal-weight women who gained less than 5 pounds during the 13-year study. (Just 13.3 percent of women studied fit that bill.)

That may sound like bad news for those people of normal weight who aren't exercising that much, not to mention everyone who is overweight or obese, says Lee. But it doesn't mean that physical activity of less than 420 minutes a week is worthless. Working out at a moderate intensity for 150 minutes a week, as the government recommends, is associated with a lower risk of many chronic diseases, no matter your weight.

But it does underline that exercise on its own, with no attention paid to calories, is unlikely to carve away excess weight or prevent gain. (Even people training for a marathon can gain weight; it's far easier to eat than to burn off what you eat.) Remember that none of these women were consciously dieting; the study can't say whether exercise is useless for overweight or obese women who are actively attempting to lose weight by also changing their eating habits. And that "usual diet" consumed by the women probably differs by their weight. It's likely that normal-weight women eat fewer calories as a matter of routine, without thinking of it as a diet.

Yet exercise also appears to be an important factor in maintaining a healthy weight, according to this and other studies. Research published in 2008 found that women who dieted and were then able to keep off 10 percent of their body weight for two years also exercised more than the government recommends, about 275 minutes a week. The amount of exercise needed to sustain a healthy weight may be in question, but the principle is consistent: Get out there and move.

workoutqueen628

Great article. Thanks for posting

muth3rluvx2

so in other words - 20 minutes a day is a load of bull.

sendmoretigers

so in other words - 20 minutes a day is a load of bull.

pretty much, but i'm pretty sure no legitimate source ever claimed that 20 minutes a day would do the trick. i think maybe a few junk peddling info-mercials have said things along those lines

i should add that 20 minutes a day is better than doing nothing, it's a starting point, at least

Azdak

so in other words - 20 minutes a day is a load of bull.

Not necessarily--you have to define your goals. The "20 min" guideline was based on early research that attempted to determine the *minimum* amount of aerobic exercise needed to increase cardiovascular fitness. Based on that definition, the guideline is perfectly appropriate.

What happens with a lot of fitness information is that bits and snippets from here and there get scraped together and generalized to subjects for which they were never intended to by used. Someone sees an "expert" guideline that you should work out "3 days/wk, 20 min a day, 60% to 75% ot maximum heart rate", takes it verbatim, and uses it as the basis for their own story about weight loss.

I would estimate that 60% to 80% of the fitness information available out there (esp on the internet) is text that is "borrowed" from another source. Do a search on a fitness topic, read an original story, and chances are you will find the exact same text used dozens of times on different web sites, all under a different author's name. It's pathetic after awhile.

The American College of Sports Medicine has stated for quite a few years that, for weight loss, a LOT more exercise is needed than 3 days/20 min. I have handouts and educational materials that I wrote in the late 1980s that say the same thing. There is accurate information out there, but the average consumer has a hard time finding it.

angelwings2000

I am still going to keep squeezing in my 20-30 minutes a day. I feel better, my muscle tone has improved and I am steadily losing weight at a a slow rate. I lead such a fast paced life, that I know if I try to et in more workout, I will not be able to maintain that over the long haul. The rest of my lfie I plan felling & looking good. My snail's pace works for me.

FireMonkey

I think "eating habits" is the key here. It appears the study didn't look at what the women were eating and took their word for it being a "normal" diet. Exercise is good for many reasons such as heart health, muscle tone, stronger bones, keeping mentally fit etc, but on its own it won't keep you healthy.

One of my friends was running every day and thought he was pretty fit; doesn't smoke; moderate drinker - a few years ago at the age of 46 he had a heart attack. His only risk factor was his terrible diet - red meat, lots of it, and starches, ditto. No vegetables or fruit. He grew up on the prairies; that may have something to do with it. Even after he recovered from the heart attack he's finding it very difficult to change his eating habits.

questionablemethods

Just to chime in on the 20 minutes a day thing. 20 minutes of a light stroll 3x/week isn't enough. But 20 minutes of super high intensity plyometrics and body weight exercises can burn a LOT of calories and 6 times a week it adds up. It isn't going to make up for a cruddy diet, but then again, most exercise plans won't.