Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Do what? exercise may make you gain weight?

  1. Aug 8, 2009 #1
  2. jcsd
  3. Aug 8, 2009 #2
    "The basic problem is that while it's true that exercise burns calories and that you must burn calories to lose weight, exercise has another effect: it can stimulate hunger. That causes us to eat more, which in turn can negate the weight-loss benefits we just accrued. Exercise, in other words, isn't necessarily helping us lose weight. It may even be making it harder."

    -straight from the article, linked above.
  4. Aug 8, 2009 #3
    I think its an excersize without dieting issue. It sounds like he is saying people excersize but then eat what ever they want or feel that since they have excersized they can go ahead and indulge in more fatty foods. Its possible that these people are over excersizing and possibly occasionally under eating which leads to them being more hungery and then binging.
  5. Aug 8, 2009 #4


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Keep in mind that muscle is denser than fat.

    The article cites a study that followed overweight women and found no correlation between amount of exercise and weight loss. OK, but what about body composition changes? I can't believe that wasn't measured. The women who exercised most may have gotten a lot smaller, but as they exchanged fat for muscle, their weight may not have changed.

    Also in that study they didn't follow any particular diet, so maybe we can say exercise alone isn't enough for some people.

    But in my personal experience, when I get injured and can't exercise, I gain weight. When I heal and start exercising again, I lose the weight. So for me, exercise certainly correlates to weight loss.
  6. Aug 8, 2009 #5
    The point is, as lisab suggests, what is weight, and is it always undesirable? I wouldn't mind converting half my fat weight into equivalent muscle mass. Cardiovascular exercise is worth its weight gain, or for me, a stable overweight. (There are several ways to measure body fat index.)
  7. Aug 8, 2009 #6
    Makes sense to me. It's long been the standard weight loss philosophy that diet is far more important than exercise for weight loss (though not general fitness)
  8. Aug 9, 2009 #7
    Indeed...good points lisa. Talk about drawing conclusions from an UNCONTROLLED experiment. But hey, it makes headlines...
  9. Aug 9, 2009 #8
    It's all about people eating more. If you burn 300 calories while working out, it is very easy to eat something with 500 calories.

    I know many people who eat several donuts and feel good about it because they worked out that day. With that mindset of course you're going to gain weight!

    In general it is much easier to get rid of calories by making cuts in your diet than by burning them off (obviously a combination is best, but this is a general statement). The effort it takes to burn 500 calories vs eating that much is not matched, so many people have a misconception that they worked SO HARD that they can eat at least that much.
  10. Aug 9, 2009 #9
    Actually, it seems they did in an off-handed way:
    "It's true that after six months of working out, most of the exercisers in Church's study were able to trim their waistlines slightly — by about an inch. Even so, they lost no more overall body fat than the control group did." quote from article.

    However, I agree with what you are saying. Change in body composition is much more important than weight change. Diet is the most important factor in a person's weight. To say that exercise is not important in a persons weight management because no attempt at an intelligent diet was made is very misleading.

    There is also a concept of set point in each person's metabolic picture that needs to be understood and can be modified. As this is a fairly recent concept and without knowing if the powers that be on this site consider it an established concept...I feel constrained to talk about it. (I already got a demerit today for the heretical statement that there was a center to the universe) But if anyone is interested, let me know and I will tell you.
  11. Aug 9, 2009 #10

    Chi Meson

    User Avatar
    Science Advisor
    Homework Helper

    Is it made clear anywhere in the study as to what was considered "exercise"? I've seen the ladies in the pool waving their arms, holding noodles and sometimes foam "weights." Occasionally waving around milk jugs partially holding water. Some of them will even knock off a lap or two of breaststroke at super-slow ("lento" in musicians' terms).

    I understand that if one is already obese, actual "working out" needs to be approached systematically, but come on, what some call exercise is pathetic.
  12. Aug 9, 2009 #11


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Yes, I think we've all seen examples of that as well. So, yes, if you don't watch your diet along with exercising, it's quite easy to defeat the value of exercising. Spending a half hour on the treadmill in the morning does not justify pigging out on a giant piece of chocolate cake at lunch time, even if you try to negate the calories by washing it down with Diet Coke (that combination always makes me laugh...if you're going to have a giant piece of cake, you might as well give up pretending you're on a diet and have real Coke along with it).
  13. Aug 9, 2009 #12
    perhaps exercise stimulates our hunger. but for me (i am a competitive runner) finishing a long and/or hard workout never really seems to make me more hungry than i was before (because i have to fast several hours before running.)
  14. Aug 9, 2009 #13
    It depends on the person I guess. I often don't feel hungery even though I ought to. If you drink alot of water that may also keep your stomach feeling full.
  15. Aug 9, 2009 #14


    User Avatar
    Science Advisor
    Gold Member

    Indeed, according to my heart rate monitor I need to run at steady pace for for 25-30 minutes (depending on what shape I am in) in order to burn 500 calories*.
    And 500 calories is about the energy content of a 100g bar of chocolate....

    *although you do continue to burn calories at at higher rate than normal for a while even after you stopped running so the actual "energy loss" is somewhat higher.
  16. Aug 9, 2009 #15


    User Avatar
    Science Advisor
    Gold Member

    What kind of running do you do?
    I really enjoy long(ish) runs that last 1.5-2 hours and sometimes more (when I am in better shape that now, that is). I don't get hungry while running but once I get home and start to relax I tend to get very hungry; although that is of course quite natural considering how much energy I just used up (and if I don't eat I get very tired and the recovery takes a long time).
  17. Aug 9, 2009 #16
    This discussion reminds me of an amusing memory on my first day as an undergraduate. After moving into my dorm there wasn't anyone to talk to and I didn't want to sit around bored so I randomly decided to go on a long exploration run. After about 3 hours I found myself out in the middle of nowhere in the woods, particularly starving and exhausted...so when I ran into a corn field, that corn looked irresistible. I tried to eat some of it it was the starchiest, nastiest thing I had ever put into my mouth!

    Back when I used to run hardcore, after running I would often treat myself to a huge root beer float that was about 60% Edy's vanilla ice cream and 40% Barq's root beer (let me tell you...there is no better combination. Something about this combination causes the ice cream to instantly develop a 2mm thick hard caramelized crust as soon as it is immersed into the root beer that is to die for). Anyway, it didn't affect my weight, as no amount of exercise, eating, working out, not working out, or lifestyle changes has ever made my weight fluctuate by more than about 2 pounds in the past 10 years...
  18. Aug 9, 2009 #17


    User Avatar

    Staff: Mentor

    The article didn't say how tall the guy was - maybe 163 lb is pretty lean and he just has a little bit of belly fat because he only does cario and never does abds?
  19. Aug 9, 2009 #18
    spot reduction is a myth. doing a bunch of crunches isn't going to preferentially reduce subcutaneous ab fat.

    which kind of relates to the main problem i have with this sort of article. where do people get this idea that having ripped abs is normal?
  20. Aug 10, 2009 #19
    f95toli- i am a distance runner. my longest race thus far is a half marathon. i also run XC for my high school.
  21. Aug 10, 2009 #20

    i experience the same problem. i can love four pounds from being sick, and it will take me several months to gain them back, if at all. otherwise, its nearly impossible for me to alter my weight, no matter how many times i go to the gym and shove massive amounts of protein down my throat..haha
  22. Aug 10, 2009 #21


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    It is widely known that, after high-intensity exercise, many people immediately go home and eat more calories than they just expended. This kind of "overshoot" is a normal phenomenon in all control systems, including the hormone-based control system used to control the human experience of hunger.

    The people most likely to fall victim to this are those who do not eat well enough before their exercise, and those that simply exercise too intently over too short a period of time.

    Our culture has polarized the idea of exercise; many people believe you're either running for your life, sweat pouring down your back, heart pounding in your ears, or you're not really exercising. Gyms, workout classes, videotapes, and exercise machine manufacturers all encourage people to think that they can be sedentary all day, then compress all their exercise down into a blistering 30-minute assault on their body, and achieve the same results. Not so, of course, and the biggest culprit is the over-eating response discussed in this thread.

    If your goal is to lose weight, high-intensity exercise is your enemy. Diet and lots of easy, light exercise are far more effective. Walking has long been considered the best exercise for weight loss, though obviously not for cardiovascular fitness.

    - Warren
  23. Aug 10, 2009 #22


    User Avatar
    Gold Member

    After months of burning up all the calories I could eat (rough paper-machine startup - bleeding-edge technology), the machine was tweaked to the point at which my job as the lead operator got more sedentary, though I kept eating those big lunches my wife packed for me. After realizing that I was putting on weight (fat), I bought a gym membership and trained there for a couple of hours a day, several days a week. I also started eating a bit lighter. The fat was gone in a couple of months, but not the weight. I had packed on a lot of muscle, and due to over-general guidelines, the plant nurse told me that I was "overweight". Not only that - when I wanted to donate blood, the Red Cross staffers made me see a supervisor after the initial screenings because they said my rest pulse rate was "too low". My BP was normal, but I had to convince the supervisor that my pulse rate was low simply because of the heavy free-weight work-outs.
  24. Aug 10, 2009 #23
    Haha...that's pretty stupid of them, but take it as a compliment! The more conditioned you are the lower your resting heart rate, the more healthy you are. My dad used to be a professional distance runner and had got his resting heart rate down to 30.
  25. Aug 10, 2009 #24
    i envy a person with a 30 bpm heart rate. after almost five years of competitive running, i cant get mine under 50.dang.
  26. Aug 10, 2009 #25
    now, these women didn't gain weight. there was simply an optimum somewhere in the middle for the given constraints.


Share this great discussion with others via Reddit, Google+, Twitter, or Facebook