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Why Doesn't Exercise Lead To Weight Loss?

Posted by timothy on from the that-would-be-too-easy dept.

antdude writes "The New York Times' Well blog reports that 'for some time, researchers have been finding that people who exercise don't necessarily lose weight.' A study published online in September 2009 in The British Journal of Sports Medicine was the latest to report apparently disappointing slimming results. In the study, 58 obese people completed 12 weeks of supervised aerobic training without changing their diets. The group lost an average of a little more than seven pounds, and many lost barely half that. How can that be?"

6 of 978 comments (clear)

  1. Hackers Diet FTW. by RGreen · · Score: 5, Insightful

    The Hackers Diet makes it clear: Exercise just doesn't burn that many calories. You can lose weight just by eating less calories than you burn, no exercise required.

    http://www.fourmilab.ch/hackdiet/www/hackdiet.html

    1. Re:Hackers Diet FTW. by iocat · · Score: 5, Insightful
      You can over-simplify calorie counting, but it isn't a myth. Eat less calories and you eventually weigh less. You may be less healthy, but I guarentee, you'll weigh less! I read some woman's magazine article one time that was like "Eating less calorines doesn't mean you lose weigh!" I was like, "really, tell that to someone starving to death..."

      Getting 150 calories from a Twinkie certainly is less beneficial than 150 calories from oatmeal, for the exact reasons you describe, but they both give your body 150 calories to use (or store...).

      --

      Dude, I think I can see my house from here.

    2. Re:Hackers Diet FTW. by stjobe · · Score: 5, Insightful

      Course, this may be more of a girl thing.

      No, no, it's absolutely not a "girl thing". There's plenty of guys that are embarrased about how they look in a gym outfit or in a pair of swimming trunks, and therefore do not go to the gym or the pool.

      Exercising next to all the ripped guys by the mirrors is intimidating for us guys as well.

      --
      "Total destruction the only solution" - Bob Marley
    3. Re:Hackers Diet FTW. by realityimpaired · · Score: 5, Insightful

      Eating some amount of calories in oatmeal and eating the same amount in breakfast cereal will have different results: your body works harder to digest the oatmeal so your metabolism is higher, resulting in lower total calories; the added fiber changes how your body digests the other food in your digestive system.

      I think this is the point, more than your point about muscle mass (though that's a valid point, too...). TFA says that these people did supervised cardio without changing their diets. If your body requires 2500 caloreis per day to maintain a healthy weight, and you're consuming 4000, then burning an extra 500 calories in cardio isn't going to make a difference.

      You're right that with a high muscle mass, it's possible to be in the "morbidly obese" category while not actually being fat or unhealthy. Professional athletes are frequently in that category, for example. But most people don't have such large amounts of muscle, and when they tip the scales at 250lbs, it's because they have much more body fat than they should. Doctors tell them thatt they should lose weight, not because they necessarily need to lose the weight, but because it's easier than testing their body composition and telling them that they have too much fat in their body. But the doctor is supposed to apply some common sense... if a male is tipping the scales at 250lbs, but wearing a 34" waist, then even though he's in the "obese" category, he's obviously not actually obese.

      If you want to lose body fat, you need to look at the big picture. It's fine and well for you to say that you ate more in exchanging 20kg of fat for muscle... but I can tell you first-hand that it doesn't work that way for females. We have to put in twice as much work to build muscles due to lower testosterone levels, and people tend to look at you weird if you're muscle-bound. Having muscle tone, and adequate strength is much better than building muscle mass, thanks to societal pressures... and that comes from cardio. But the only way you're going to lose weight through cardio is by not consuming way more calories than you need. It's well and good that you're in the cardio zone, and burning fat calories (I run 6 miles a day, and usually finish under 45 minutes, for example), but if you're still consuming way more calories than your body actually needs (including the extra 500-700 you'd burn from that level of cardio workout), then you're not going to lose weight. It's becoming a tired mantra, but it's no less true: eating less and exercise is the only way to do it.

  2. Re:How can that be? by DeadDecoy · · Score: 5, Insightful

    I think we as a culture are too used to being sold quick weight loss 'solutions'. True fitness, as you say, comes from a change in lifestyle, where one should be exercising not for 12 weeks but for several years to be in a healthy state. Unless you go through some painful and hellish training regimen, getting fit doesn't happen quick.

  3. Re:Unfortunately not by drgonzo59 · · Score: 5, Insightful

    That is not true. In starvation mode the body will use the fat first and then the muscle. A body without muscle and all fat is useless. In other words, look at the victims of famine, they usually can still move even though they are emaciated, _but_ they are not fat. If muscle would burn first, they would just end up as sacks of lard + bones completely unable to move. If such an organism ever evolved it probably, it would have quickly died out out as it would not be very efficient.