# Health and fitness myths that need to die. **URL:** \ **Category:** In My Humble Opinion\ **Created:** [October 30, 2014, 9:00pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054 "2014-10-30T21:00:49Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [October 31, 2014, 4:31pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/41 "2014-10-31T16:31:53Z")
If two identical twins were matched up. One twin used weights and other muscle building activities while the other read books and surfed the internet. Twin #2 has 20# more lean muscle mass than twin #1. Will the twin with more muscle mass burn more calories while just sitting than twin #1? ---
**Author:** ![Richard\_Parker](https://avatars.discourse-cdn.com/v4/letter/r/35a633/32.png) [@Richard\_Parker](https://boards.straightdope.com/u/Richard_Parker)\ **Post date:** [October 31, 2014, 4:34pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/42 "2014-10-31T16:34:11Z")
Yes. Just maintaining muscle takes more energy. ---
**Author:** ![Hello\_Again](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@Hello\_Again](https://boards.straightdope.com/u/Hello_Again)\ **Post date:** [October 31, 2014, 4:37pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/43 "2014-10-31T16:37:00Z")
Mine is “starvation mode.” Yes, it’s true if you cyclically starve then binge, you’re going to screw up you metabolism along the human body’s famine-adapted pathways. No, it is not true that if you consistently eat fewer calories than you burn you will magically become fat or unable to lose weight. Thermodynamics do not work that way. It actually IS possible to starve to death! You don’t just keep getting fatter on air. Way too many people use “starvation mode” as an excuse to cram food on their face. “I have to eat more! To avoid starvation mode!” ---
**Author:** ![QuickSilver](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quicksilver/32/7832_2.png) [@QuickSilver](https://boards.straightdope.com/u/QuickSilver)\ **Post date:** [October 31, 2014, 4:44pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/44 "2014-10-31T16:44:50Z")
> [@Pabitel](#): > > The biggest myth for those obsessed with fitness is that more is always better. > It is very possible to overexercise and it can kill you as easily as remaining a couch potato can. > [Cite](http://www.menshealth.com/health/death-exercise) > [Cite](http://www.medpagetoday.com/Cardiology/Prevention/45785) > [Cite](http://www.mayoclinicproceedings.org/article/S0025-6196(12)00473-9/abstract?cc=y) I think we can all agree that moderation in all things is probably the best choice. Still, if mortality rates are grim for both extremes, do you think there is anything to be said about the quality of life of an physically fit individual vs a sedentary individual? Or should we assume that dead is dead, so what does it matter if you die fit or die fat? ---
**Author:** ![RTFirefly](https://avatars.discourse-cdn.com/v4/letter/r/c77e96/32.png) [@RTFirefly](https://boards.straightdope.com/u/RTFirefly)\ **Post date:** [October 31, 2014, 5:44pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/45 "2014-10-31T17:44:34Z")
> [@Richard\_Parker](#): > > I thought most daily fluctuation was just a matter of water retention and how quickly your bowel happened to be working. Wouldn’t you just be learning which foods cause you to retain more water or digest more slowly by focusing on daily changes? When I weigh myself in the morning, it’s usually been 8-9 hours since I’ve last eaten, so hopefully most of that’s evened out by then. Yeah, I suppose a food could fool me if it consistently caused one of those effects to hold up overnight, but if it was a food I ate regularly, either I’d be gaining weight over time or I wouldn’t. I might scratch a food off my OK list on the basis of what was essentially a false positive, but that’s about as much downside as I can see. ---
**Author:** ![RTFirefly](https://avatars.discourse-cdn.com/v4/letter/r/c77e96/32.png) [@RTFirefly](https://boards.straightdope.com/u/RTFirefly)\ **Post date:** [October 31, 2014, 5:47pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/46 "2014-10-31T17:47:52Z")
> [@QuickSilver](#): > > I think we can all agree that moderation in all things is probably the best choice. Still, if mortality rates are grim for both extremes, do you think there is anything to be said about the quality of life of an physically fit individual vs a sedentary individual? Or should we assume that dead is dead, so what does it matter if you die fit or die fat? Certainly dead is dead, but if I live a long time, I’d like to enjoy as many of those years as much as possible, and being in at least decent physical shape will probably help a lot with that. And if I can stay in shape by doing stuff I like, like (in my case) bicycling or hiking, then it’s win-win: I’m having a better time now, and I should be in better health when I’m 80. ---
**Author:** ![VinylTurnip](https://avatars.discourse-cdn.com/v4/letter/v/b2d939/32.png) [@VinylTurnip](https://boards.straightdope.com/u/VinylTurnip)\ **Post date:** [October 31, 2014, 5:55pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/47 "2014-10-31T17:55:18Z")
> [@Richard\_Pearse](#): > > Given that exercising until you puke is not uncommon, yes. I wonder if they also mean that you literally should never quit exercising. Because to me, that sounds really tough. ---
**Author:** ![Richard\_Parker](https://avatars.discourse-cdn.com/v4/letter/r/35a633/32.png) [@Richard\_Parker](https://boards.straightdope.com/u/Richard_Parker)\ **Post date:** [October 31, 2014, 5:59pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/48 "2014-10-31T17:59:18Z")
> [@RTFirefly](#): > > When I weigh myself in the morning, it’s usually been 8-9 hours since I’ve last eaten, so hopefully most of that’s evened out by then. Yeah, I suppose a food could fool me if it consistently caused one of those effects to hold up overnight, but if it was a food I ate regularly, either I’d be gaining weight over time or I wouldn’t. I might scratch a food off my OK list on the basis of what was essentially a false positive, but that’s about as much downside as I can see. The point is that daily fluctuations in weight don’t tell you much about how much fat and muscle you’re putting on or taking off. That’s because not all weight variation involves the addition or deletion of body tissues. There are lots of ways to gain weight between Tuesday and Wednesday that will disappear by Thursday regardless of your overall caloric intake and activity level, from water retention to glycogen retention to the weight of undigested food itself. Water retention in particular accounts for most of the daily fluctuations, and can be affected by a whole range of things from sodium content, to overall hydration, to activity. So assuming you are weighing yourself to assess progress on some program to lose fat, or maintain fat, or gain muscle, or some other long-term change, there’s way too much noise in daily measurements to be useful in assessing whether you did the right thing yesterday in your diet. With very efficient and regular bowel movements, I suppose you can control for undigested food. But I don’t think you can really control for water retention. ---
**Author:** ![Hello\_Again](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@Hello\_Again](https://boards.straightdope.com/u/Hello_Again)\ **Post date:** [October 31, 2014, 7:26pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/49 "2014-10-31T19:26:25Z")
That’s all true but there’s a pretty strong correlation between maintaining weight loss and weighing yourself regularly. ---
**Author:** ![Richard\_Parker](https://avatars.discourse-cdn.com/v4/letter/r/35a633/32.png) [@Richard\_Parker](https://boards.straightdope.com/u/Richard_Parker)\ **Post date:** [October 31, 2014, 8:17pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/50 "2014-10-31T20:17:05Z")
> [@Hello\_Again](#): > > That’s all true but there’s a pretty strong correlation between maintaining weight loss and weighing yourself regularly. I’m sure there is. I’m sure there’s also a strong correlation between caring about your weight and weighing yourself regularly, and between caring about your weight and doing something about it. But whether it is helpful or harmful to discipline, it is almost certainly fruitless to try to correlate daily changes in weight to diet, if your goal is to fine tune your diet for personal fat loss. If you really think there’s something magic about daily instead of weekly weigh-ins, the simple solution would be to do some kind of rolling average. Indeed, I’ll bet RTFirefly could design such a model far better than I could. 🙂 ---
**Author:** ![Hello\_Again](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@Hello\_Again](https://boards.straightdope.com/u/Hello_Again)\ **Post date:** [October 31, 2014, 8:53pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/51 "2014-10-31T20:53:00Z")
No, I don’t think there’s anything magic about daily weighin (or any schedule of weigh ins) . And I agree that trying to tie it to your specific diet is a fools errand, especially for women. But it’s not an obviously harmful or invalid process or a “myth” that it helps with weight loss. All signs point to it being helpful. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [October 31, 2014, 9:49pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/52 "2014-10-31T21:49:34Z")
Well it is _associated with_ better weight loss and weight loss maintenance but the question always is if it is a marker (for self-discipline and concern) or a contributing factor. And it _may_ be a marker more than anything else afterall. [A recent large RCT](http://www.ijbnpa.org/content/11/1/125) found daily weighing to be ineffective in facilitating greater weight loss. ---
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [October 31, 2014, 10:12pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/53 "2014-10-31T22:12:23Z")
> [@The\_Joker\_and\_the\_Thief](#): > > Interesting post. I graphed the points and then fitted them with a logarithmic function, then factored in the time spent walking. Turns out walking 7.5 hours/week only becomes optimal if you’re over 47–otherwise, you’ll spend more time walking than you’ll gain in life expectancy. > > And that doesn’t even factor in diminishing marginal returns–a 47 year old walking 4 hours a week gets 94% of the time he would have at 7.5 hours a week, and he’s getting better quality time when he’s younger rather than when he’s older. > > In other words: just go out and walk for a couple hours a week. I wonder if you have to spread those walks out. I’m the kind of person that would rather go on a couple 1.5 hour walks than six 30 minute walks. I wonder if that matters, and if so how much. ---
**Author:** ![Hello\_Again](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@Hello\_Again](https://boards.straightdope.com/u/Hello_Again)\ **Post date:** [October 31, 2014, 10:52pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/54 "2014-10-31T22:52:35Z")
> [@DSeid](#): > > Well it is _associated with_ better weight loss and weight loss maintenance but the question always is if it is a marker (for self-discipline and concern) or a contributing factor. > > And it _may_ be a marker more than anything else afterall. [A recent large RCT](http://www.ijbnpa.org/content/11/1/125) found daily weighing to be ineffective in facilitating greater weight loss. This is a far cry from saying it a hurtful lie which must be stamped out. I realize I’m being trivial, picayune, and redundant, but as Great Evil Myths of Weight Loss go this one is pretty far down the list. The worst you can say for daily weigh-ins is that its not clearly the cause of weight loss or weight loss maintenance. But I suppose at the end of the day the thread is for things that bug us, and not necessarily the Worst Things Ever. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [October 31, 2014, 11:33pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/55 "2014-10-31T23:33:17Z")
Completely agreed. ---
**Author:** ![Silvorange](https://avatars.discourse-cdn.com/v4/letter/s/8dc957/32.png) [@Silvorange](https://boards.straightdope.com/u/Silvorange)\ **Post date:** [November 1, 2014, 12:41am UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/56 "2014-11-01T00:41:31Z")
> [@Richard\_Parker](#): > > If you really think there’s something magic about daily instead of weekly weigh-ins, the simple solution would be to do some kind of rolling average. [Like this?](http://www.weightgrapher.com/) I’m a daily weigher, but it’s the overall trend that’s important. ---
**Author:** ![OneCentStamp](https://avatars.discourse-cdn.com/v4/letter/o/13edae/32.png) [@OneCentStamp](https://boards.straightdope.com/u/OneCentStamp)\ **Post date:** [November 1, 2014, 1:00am UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/57 "2014-11-01T01:00:05Z")
I weigh myself daily, but graph my weekly average. That way, one sturdy dump, or one bowl of salty chips that makes me hold on to two pounds of water weight overnight, don’t throw me into unnecessary despair or ecstasy. ---
**Author:** ![DinoR](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dinor/32/2821_2.png) [@DinoR](https://boards.straightdope.com/u/DinoR)\ **Post date:** [November 1, 2014, 4:26pm UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/58 "2014-11-01T16:26:56Z")
> [@Hello\_Again](#): > > This is a far cry from saying it a hurtful lie which must be stamped out. I realize I’m being trivial, picayune, and redundant, but as Great Evil Myths of Weight Loss go this one is pretty far down the list. The worst you can say for daily weigh-ins is that its not clearly the cause of weight loss or weight loss maintenance. Forwarding the email that said Microsoft would pay you to send it to everyone wasn’t evil either. There was a myth behind it. A nice moderate diet to lose 1lb a week is on average .14 lbs a day. That’s easy to get lost behind a couple pounds of water and bowel weight variance. If the person implements a strength training program for exercise it’s can be further obscured behind added muscle mass. Fat loss is good but muscle gain is good and your scale can’t tell the difference. Throw the muscle gain and fat loss together and you can be pushing the accuracy of most home scales. With care and effort a minority (Although probably more in sample from here ;)) can pry out the truth behind the daily fat loss Some might still miss it with muscle mass changes. At best it’s minimal gain in information for the effort. Personal values on the marginal cost of the time to track and analyze the data will decide if it’s worth it to them. How many really do that in the population exposed to the notion that weighing more often is better? In my anecdotal experience few. I actually talked someone down from the twice a day weighing when they were going to get “serious” about losing weight. I’ve seen day to day dietary yo-yoing and mood swings based on the day to day noise from the scale. I’ve seen people consider quitting because they were tired of the emotional load from the measurement. A possible small benefit for a minority vs a negative for a majority - I consider that a downside to a myth that you should/need to/won’t lose weight if you don’t. I won’t say its evil. It’s not saying everyone should stop doing it. I do encourage people in my life to think about it. I think they’d be even better off if they hid the scale completely or only used it monthly and instead used a weekly method to compute body fat like a simple [tape test.](http://www.calculator.net/army-body-fat-calculator.html?ctype=standard&csex=f&cage=21&cheightfeet=6&cheightinch=0&cneckfeet=1&cneckinch=4.5&cwaistfeet=3&cwaistinch=0&cwaistfeetf=3&cwaistinchf=0&chipfeet=2&chipinch=10.5) That’s more work though and for those with very high body fat the difference is negligible. Beside for the ones that are day to day diet and exercise adjusting that’s usually way to far to expect them to make a change. Baby steps. ---
**Author:** ![lorene](https://avatars.discourse-cdn.com/v4/letter/l/65b543/32.png) [@lorene](https://boards.straightdope.com/u/lorene)\ **Post date:** [November 2, 2014, 3:38am UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/59 "2014-11-02T03:38:20Z")
Well, this is working out well to clear up any myths. ETA: mine is that any food eaten after a certain time of night will “turn to fat.” ---
**Author:** ![Ambivalid](https://avatars.discourse-cdn.com/v4/letter/a/a5b964/32.png) [@Ambivalid](https://boards.straightdope.com/u/Ambivalid)\ **Post date:** [November 2, 2014, 3:56am UTC](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054/60 "2014-11-02T03:56:23Z")
> [@lorene](#): > > ETA: mine is that any food eaten after a certain time of night will “turn to fat.” Similarly, the notion that unused muscle mass will “turn to fat” over time. [Previous page](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054.md?page=2) [Next page](https://boards.straightdope.com/t/health-and-fitness-myths-that-need-to-die/703054.md?page=4)