Exercising on an empty stomach burns muscle instead of fat?!

Options
Whoa, is this true?
Does exercising on an empty stomach really burn muscle instead of fat?
How did I not know this before...
Can someone please confirm, deny, discuss

http://www.fitsugar.com/Best-Food-Eat-Before-Workout-18055907

Replies

  • scottb81
    scottb81 Posts: 2,538 Member
    Options
    No, it's not true. It doesn't even make any sense physiologically. The only time you are going to burn muscle tissue is if you are on a starvation diet and have been on it for a long time. If you haven't eaten for several weeks and look like you are a concentration camp inmate then you will burn muscle tissue because there is nothing left to burn.
  • Matt_Wilken
    Options
    You start burning muscle tissue and fat when you have depleted your glycogen stores during exercise. Therefore it is essential to try and meet your daily protein intake of at least 1 gram of protein per pound of lean body mass to try and preserve most of your muscle mass when cutting down.
  • sijomial
    sijomial Posts: 19,811 Member
    Options
    I thought glycogen stored in the muscles and liver was the energy store that the body uses first.
    Unless you are doing an endurance event I don't believe you need to eat before a workout.
  • EdTheGinge
    EdTheGinge Posts: 1,616 Member
    Options
    What a load of cobblers
  • Janelle173
    Janelle173 Posts: 396 Member
    Options
    What a load of cobblers

    mmmm cobbler!

    haha i am thankful this is not true! i'd be really backpedaling as of late!
  • Hendrix7
    Hendrix7 Posts: 1,903 Member
    Options
    http://pulsthjalfun.is/wp-content/uploads/2011/11/doescardio.pdf

    ^^

    Full text of study the article is referencing.

    Most of this is not relating to muscle loss, rather it just confirms what we already know, overall calorie expenditure of the exercise is more important that trying to manipulate nutrients to maximise fat loss from the exercise.

    The part about muscle loss is a bit more flimsy as it only talks about nitrogen loss, this in itself does not show that exercise while fasted actually causes muscle loss over time as nitrogen balance would be restored with any post-exercise protein you ate. Long term muscle loss/growth still comes down to overall calories. Is anyone in the real world actually going to attempt any long distance cardio like a marathon in a fasted state....I doubt it. Most bodybuilders doing fasted cardio are doing 1hr on the step machine at the most.

    Cliffs
    - Do whatever exercise you prefer, whenever you prefer to do it
    - Hit your macros and you will be ok in the long run.
  • xidia
    xidia Posts: 606 Member
    Options
    I thought glycogen stored in the muscles and liver was the energy store that the body uses first.
    Unless you are doing an endurance event I don't believe you need to eat before a workout.

    Yes, this. Then fat and blood sugar. Breaks between sets in weights workouts are to allow the muscle glycogen stores to replenish.

    For endurance, it's more complicated and depends on the exertion level and the body's efficiency at converting fuel stores to energy.

    I tend to eat before a cardio workout because I deliberately work above the rate where my body can burn fat to fuel it, and I'm not doing cardio to shed fat, I'm doing it to increase endurance. If I wanted to purely burn fat from cardio, I'd spend twice as long at half the exertion level, because that's where my body can burn fat for fuel.
  • Claire_x90
    Options
    It's slightly different between men and women.

    But does it really matter about the science behind it? Don't you want to eat before you work out? you can go with that much more effort and energy when you have something

    What's the point if it's just half assed effort and you end up feeling faint and gross?
  • johloz
    johloz Posts: 176 Member
    Options
    It's slightly different between men and women.

    But does it really matter about the science behind it? Don't you want to eat before you work out? you can go with that much more effort and energy when you have something

    What's the point if it's just half assed effort and you end up feeling faint and gross?

    First of all, how is it different for men vs women? Would love to know this info.

    And when it comes to eating first to feel energy, everyone's different -- if I eat anything before a work out (doesn't matter what or how much), I feel sick and sluggish when exercising. I prefer to eat after I workout. And since I'm one of the most muscular women I know, I'm obviously doing something right. If you workout better if you eat before, do that. If you workout harder on an empty stomach, do that. The time you eat isn't as important as what you eat and how much you eat. Yes, timing of meals matters a little bit, but unless you are in training, the little bit won't matter enough to notice.
  • pinkraynedropjacki
    pinkraynedropjacki Posts: 3,027 Member
    Options
    It's slightly different between men and women.

    But does it really matter about the science behind it? Don't you want to eat before you work out? you can go with that much more effort and energy when you have something

    What's the point if it's just half assed effort and you end up feeling faint and gross?

    I know for me I can't go for a run on a full stomach, in fact I make sure I run on an empty stomach..... or else it's handy to know where a toilet is on the route.

    Nothing half assed about a 10km run.
  • tubbyelmo
    tubbyelmo Posts: 415 Member
    Options
    I use my exercise bike before breakfast a few days a week, I found this article a few months ago, made me feel quite virtuous about my pedaling!

    http://well.blogs.nytimes.com/2010/12/15/phys-ed-the-benefits-of-exercising-before-breakfast/
  • tigersword
    tigersword Posts: 8,059 Member
    Options
    It's slightly different between men and women.

    But does it really matter about the science behind it? Don't you want to eat before you work out? you can go with that much more effort and energy when you have something

    What's the point if it's just half assed effort and you end up feeling faint and gross?
    If your effort is half assed and you feel faint and gross just because you happened to decide to work out first, then eat, then you aren't eating enough in general. Your body runs on total calories, doesn't matter when you get them. Just like your car runs on the total amount of gas you put in, doesn't matter when you put the gas in.

    It takes roughly 12 hours for your body to digest food (3 days if you include the time spent in the large intestine.) There's no reason why you wouldn't have energy to do a hard workout without eating right before hand, barring starvation or illness.
  • scottb81
    scottb81 Posts: 2,538 Member
    Options
    If you eat right before the main thing you do is raise your insulin level and cause the body to burn more glycogen instead of fat. If the purpose of the workout is to build aerobic endurance that reduces the effectiveness of the workout.
  • Sarauk2sf
    Sarauk2sf Posts: 28,072 Member
    Options
    http://pulsthjalfun.is/wp-content/uploads/2011/11/doescardio.pdf

    ^^

    Full text of study the article is referencing.

    Most of this is not relating to muscle loss, rather it just confirms what we already know, overall calorie expenditure of the exercise is more important that trying to manipulate nutrients to maximise fat loss from the exercise.

    The part about muscle loss is a bit more flimsy as it only talks about nitrogen loss, this in itself does not show that exercise while fasted actually causes muscle loss over time as nitrogen balance would be restored with any post-exercise protein you ate. Long term muscle loss/growth still comes down to overall calories. Is anyone in the real world actually going to attempt any long distance cardio like a marathon in a fasted state....I doubt it. Most bodybuilders doing fasted cardio are doing 1hr on the step machine at the most.

    Cliffs
    - Do whatever exercise you prefer, whenever you prefer to do it
    - Hit your macros and you will be ok in the long run.

    ^^this

    The study that seems to be the only one that discusses muscle loss is the one by Mullin and Lemon (I think this is the one you are referring to). I am not sure how they got to the conclusion in that study which was :

    "It was concluded that protein is utilized during exercise to a greater extent than is generally assumed and that under certain conditions protein carbon may contribute significantly to exercise caloric cost"

    to the conclusions in the pdf (which did not really note the context) and then to the even more more adamant statement in the article in the OP (especially as nitrogen balance is a flawed way to look at protein synthesis/breakdown in the first place).
  • Kagami_Taiga
    Kagami_Taiga Posts: 124 Member
    Options
    It's slightly different between men and women.

    But does it really matter about the science behind it? Don't you want to eat before you work out? you can go with that much more effort and energy when you have something

    What's the point if it's just half assed effort and you end up feeling faint and gross?

    I swim first thing in the morning before lectures. I tend to eat AFTER I've finished. But even eating before the swim I've not noticed any difference to my performance at all.

    I base this on the records I keep. I take note of the number of length in an hour, my quickest length time and highest number of continuous lengths.
  • Sarauk2sf
    Sarauk2sf Posts: 28,072 Member
    Options
    It's slightly different between men and women.

    But does it really matter about the science behind it? Don't you want to eat before you work out? you can go with that much more effort and energy when you have something

    What's the point if it's just half assed effort and you end up feeling faint and gross?

    How is it slightly different between men and women?
  • Boocakes08
    Options
    Peach cobbler! Yummy!
  • Claire_x90
    Options
    Oh wow I didn't realize there was so many responses to my post or I would have come on here earlier!

    To the men vs woman remark, this is the impression I am under

    "Women are better at burning fat in response to exercise. During endurance exercise, they exhibit lower respiratory exchange ratios than men, which indicates more fat burning and less carb burning." ( www.nrcresearchpress.com/doi/abs/10.1139/h00-024 )

    also of course the level your heart rate is at determines whether once you deplete immediate energy stores if you go to muscle or fat. it is easier for a man to get his heart rate into the protein burning stage with the same amount of effort (anything a man can do a woman can do as well, go feminists etc I know, just for men it does biologically take less effort to do so)

    Of course finding what is best for you is what matters and blah blah blah. I can't exercise on a full stomach either, but I can't exercise productively on an empty one. This only comes into play when I exercise in the morning, usually it's about 16 or so hours since I've eaten. If I exercise at night and it's only 5 or 6 hours since I ate it doesn't seem to make a substantial difference.

    If others can still feel tough and strong and like they are giving it their all without any food or shakes or anything then all the power to you!
  • Jesse_Hunter
    Jesse_Hunter Posts: 162 Member
    Options
    I always workout in a fasted state, because I practice Intermittent fasting.

    I will never go back to eating before a workout. I have never had more energy, more strength, and more muscle gain faster than I have training this way, believe it or not...

    I don't want to say that, anyone can successfully train fasted. I do agree that we are all different. However, I feel that the majority of the problems people run into when attempting to workout in a fasted stage is simply their "food conditioning", If you will. Basically, I mean that your body and mind have adapted to your eating routine. I fasted many times, and broke all chemical dependencies to food before I ever tried fasted training, so this absolutely helps explain my wonderful results with it.

    Regular consumption of refined sugar, and/or caffeine will cause the most problems with being able to function in a fasted state, in my experience. It is definitely something you have to stick with for a few days, maybe even longer sometimes in order to cleanse the body of such chemical dependencies. After you flush all of that out, I bet most people will find it very enjoyable!

    Also, New scientific research suggests that fasting raises Human growth Hormone 1500-2000% in males. I don't know if that is 100% positive, but I am gaining muscle quite fast.

    Ultimately, you have to step back here and look at things from an evolutionary perspective. If working out in a fasted state really burned all your muscle away, and produced weaker, less efficient results...you wouldn't be here to write about it. We know that our ancestors didn't have 24/7 access to food. A lot of times, they didn't have access to food at all, that is why we are so efficient at storing fat. A nomadic tribe of 30 people might have killed one bison, consumed it all in one big feast and then not had another meal for 3 days. Yet, along the way still having to travel, attempt to hunt, and do manual labor. We see these same patterns in many wild animals. The point is, our bodies were designed to be extremely efficient at fasting and performing simultaneously.