Can someone explain to me why my body would burn protein/muscle?

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  • I was reading somewhere that the body burns carbs/sugar (?) then fat then protein/muscle. But I have so much fat that I can't imagine it ever getting a chance to burn muscle no matter how much exercise I get!

    So does this mean I don't have to worry about burning muscle?

    Also, if I'm burning 30-50% fat calories then what is the other % that I'm burning? Different calories? It's not fat that's being burned??

    And does none of this fat calorie burnage start until I bun all the carbs??

    Obviously I'm seriously confused so feel free to just put a link to a helpful article if it's too much info to type out. THanks!
  • Unless you are at a point where you close to 18% body fat or lower, I wouldn't worry about these numbers. I use a heart rate monitor and I try to stay in my fat loss zone for the most part. But I love having great workouts where my heart rate gets a little higher. Here is a fact - the lower your heart rate, you burn a higher percentage of fat calories. The higher your heart rate, the less PERCENTAGE of fat you are burning. If you get your heart rate up, say above 180, you will probably start burning a higher percentage of protein/muscle especially on an empty stomach. But don't worry so much about all of this, just have a great calorie burning work out. And cross-train! Vary your routines while adding in strength training at the same time.

    Watching TV for 20 minutes
    40 calories - total calories burned
    60 percent - percentage of fat
    24 calories - total fat calories

    Walking for 20 minutes
    100 calories - total calories burned
    65 percent - percentage of fat
    65 calories - total fat calories burned

    Jogging & sprinting for 20 minutes
    250 calories - total calories burned
    35 percent - percentage of fat
    88 calories - fat calories burned
  • In an anerobic state (high intensity exercise) your body will use calories first from stored glycogen (which is the product of sugar carbs) for energy.. this is the bodies PREFERRED METHOD. your body can only oxidize fat in an AEROBIC capacity (meaning you burn most of your fat while sleeping, sitting on the couch, folding laundry, that type of stuf) If you are out of "energy"--> glycogen, and your body needs ENERGY NOW (cuz youre exercising or whatever, and you have no glycogen) your body CAN break down proteins in your myscles to use as fuel... burning fat takes too long..... and in an oxygen depleted state, it just cant do it
  • By the way, the other calories are carbohydrates that you are burning. If you are working out and haven't eaten in more than three hours, you won't have as much carbs to burn. But you also lose energy more quickly and may not have the stamina to work out at a higher intensity. There is always a trade off, just focus on having workouts where you are burning lots of calories or where you are adding strength. You will meet your goals more quickly if you don't focus so much on where the calories are coming from.
  • Ok... I'm going to try to explain this as best I can and simply but I'm not an expert and the information I have I've basically collected from reading about it myself. Just so you know, everything you eat needs to be processed by the body before it's used for energy. If you eat it and your body doesn't need it, it will either be processed through digestion and pooped out or you will store it as fat.

    You eat and consume 3 different types of food energy: protein, carbs, and fats. These macronutrients are all used by your body for cell function and repair. Cells mainly use glucose for energy which is just a very small sugar/carbohydrate. There are many kinds of sugars (I'm sure you've heard of fructose and so on) that the body basically wants to break down into something it's cells can use. Everything you eat is basically processed by the liver and a few other organs to turn into usable energy (all of this occurs in complex processes like glycolosis, I'm sure you've heard of ATP in high school biology). You usually have a set blood sugar level that your body maintains for immediate energy which is usually not that high in a regular person (because how much energy does one really need to pick up a pen and write?) Now let's say you are moving around and picking heavy things up. You are going to deplete your blood sugar stores and your body is going to look for it's next immediate source of energy to burn which is usually fat. Hormones are released that trigger certain organs to get fat cells to release their stored energy so that your heart can beat, your muscles can move... So on. Fats are pretty much energy, that needs to be processed as well.

    As you lose weight, you will be losing a little muscle in addition to fat. You can't really get around this, you're intentionally putting yourself in a calorie deficit. Protein (what your muscles are made of) is composed of amino acids. Your cells can only make and manufacture a certain number of these acid chains, you need the rest through diet. That is primarily why we consume animal flesh. THESE AMINO ACIDS ARE CRUCIAL FOR BRAIN FUNCTION AND CELLULAR REPAIR. If you are not getting protein through diet your only available stores are going to be muscle tissue. The goal with losing weight is to preserve as much muscle tissue as possible (because it's metabolically active and burns more energy than fat.) You will need to make sure you are eating enough. The best way to retain muscle and promote muscle growth is to lift heavy weights.

    Ok... So to answer your questions:

    So does this mean I don't have to worry about burning muscle?
    No... You will only experience muscle deterioration when you do not eat enough protein or you are starving but since you're trying to lose weight, it's pretty much inevitable that you'll lose a little bit of lean muscle mass. You can preserve and build strength though by incorporating a weight ligfting routine into your diet.

    Also, if I'm burning 30-50% fat calories then what is the other % that I'm burning? Different calories? It's not fat that's being burned??
    After blood sugar is depleted you are going to be burning some fat but it's not anything drastic. Most of your burned energy is simply going to happen from being alive.

    And does none of this fat calorie burnage start until I bun all the carbs??
    Kind of. After blood sugar, you're using fat stores but don't worry about losing all this fat through exercise. Exercise will make your heart healthy and give you muscle and maybe create a little bit of a calorie deficit but most of your weight loss is going to happen through diet.


    I have to go to lunch but I'll try to proof it better when I get back. Hope that helps.
  • I've always read that exercise and eating sufficient protein will minimize or prevent muscle loss.

    I don't remember the protein level that is generally considered "sufficient," to prevent muscle loss, because I lose best on a moderately low-carb diet so I was eating far more than the minimum. I eat 6 - 12 protein exchanges daily (the equivalent of 6 to 12 ounces of meat or fish - though meat and fish accounts for only about half of my protein. I also eat eggs, cheese, yogurt, nuts and beans and soy protein).


    If you can see a dietitian, I'd highly recommend it (remember to bring your list of questions). If you don't have insurance to cover it, sometimes the health department will offer free or very low-cost services. If you have a low to middle income, and have children under a certain age you also may
    qualify for WIC programs which include nutrition counseling.

    I'm not assuming you're in a low income bracket, just in this economy many of us are.
  • "So does this mean I don't have to worry about burning muscle?
    No... You will only experience muscle deterioration when you do not eat enough protein or you are starving but since you're trying to lose weight, it's pretty much inevitable that you'll lose a little bit of lean muscle mass. You can preserve and build strength though by incorporating a weight lightning routine into your diet.

    Also, if I'm burning 30-50% fat calories then what is the other % that I'm burning? Different calories? It's not fat that's being burned??
    After blood sugar is depleted you are going to be burning some fat but it's not anything drastic. Most of your burned energy is simply going to happen from being alive."

    I think she is talking about her calorie burn during the workout. As in what type of calories is she burning? Not on a daily or sendentary basis....
  • Quote: If you can see a dietitian, I'd highly recommend it (remember to bring your list of questions). If you don't have insurance to cover it, sometimes the health department will offer free or very low-cost services. If you have a low to middle income, and have children under a certain age you also may
    qualify for WIC programs which include nutrition counseling.
    Yes to this. If you can see a nutritionist, DO see a nutritionist. I've recently started going to one and it's helped a lot, even just for motivational purposes. But beyond that she knows where to shop, what brands to buy, ways to combine food to decrease hunger etc. She worked with my existing diet and made realistic changes that I can stick to so it wasn't like I had to overhaul everything. Oh, and she does this all with out making me calorie count (something that just does not work for me).

    Back to your original question. I think others have answered the timing aspect already but I wanted to reiterate. EAT PROTEIN. Seriously if you're working out at intense levels it always helps to have a lot of protein in your diet. It cuts back on your hunger levels, helps you avoid muscle loss, and it tastes pretty good too! Also, do heavy weight lifting. It's the best way to maintain/build muscle. If you don't have a routine established check out the New Rules of Lifting for Women. My DH even enjoyed reading it and we both learned a lot.
  • madamezombie is right on.

    the bottom line, eat enough calories and eat or drink good quality protein.
    Hubby drinks 1/2 EAS shake before workout and the other half within 20 -30 mins. after workout.
  • Quote: Also, if I'm burning 30-50% fat calories then what is the other % that I'm burning? Different calories? It's not fat that's being burned??
    After blood sugar is depleted you are going to be burning some fat but it's not anything drastic. Most of your burned energy is simply going to happen from being alive."

    I think she is talking about her calorie burn during the workout. As in what type of calories is she burning? Not on a daily or sendentary basis....
    I addressed that exactly. After she uses up available energy in the blood during a workout, she is going to address her fat stores. The calories she is burning is from sugar, the rest from adipocytes that release stored fatty acids into the blood as free fatty acids, in order to supply muscle cells with energy. I simply added that although she is going to be burning some energy during a workout, most of the energy will be burned off while she is just up and about living her daily life. I don't know the specific percentage, I just know the general order of the processes. Carbs then fat.
  • Quote: Unless you are at a point where you close to 18% body fat or lower, I wouldn't worry about these numbers. I use a heart rate monitor and I try to stay in my fat loss zone for the most part. But I love having great workouts where my heart rate gets a little higher. Here is a fact - the lower your heart rate, you burn a higher percentage of fat calories. The higher your heart rate, the less PERCENTAGE of fat you are burning. If you get your heart rate up, say above 180, you will probably start burning a higher percentage of protein/muscle especially on an empty stomach. But don't worry so much about all of this, just have a great calorie burning work out. And cross-train! Vary your routines while adding in strength training at the same time.
    This information isn't entirely correct. Your body doesn't cannibalize muscle for energy unless it is in desperate need of protein and that usually doesn't happen through a decent diet and moderate exercise, even if you're exercising on an empty stomach. Also, the low intensity "fat burning zone" is a myth. Here is further reading on the topic.

    The only time you're going to immediately go for protein is when it's already in the blood (maybe you had a nice high protein snack before working out) because outside of muscle tissue, you have no way to store protein. Glycogen is also stored in muscle tissues. However, it is the glycogen in them and not the tissues themselves that get burned while you are exercising.
  • I disagree with the above. And point out what was stated my another member who commented on this post:
    "your body CAN break down proteins in your myscles to use as fuel... burning fat takes too long..... and in an oxygen depleted state, it just cant do it"
  • Trainers tend to disagree on the "fat burning zone". But who cares? If it's been working for me and I've seen great results by basing my training on it, then I'll continue to do it. Do what works for YOU.

    (I do CrossFit as well. And even some Crossfit trainers tend to disagree on this subject matter)
  • Quote: I disagree with the above. And point out what was stated my another member who commented on this post:
    "your body CAN break down proteins in your myscles to use as fuel... burning fat takes too long..... and in an oxygen depleted state, it just cant do it"

    Trainers tend to disagree on the "fat burning zone". But who cares? If it's been working for me and I've seen great results by basing my training on it, then I'll continue to do it. Do what works for YOU.

    (I do CrossFit as well. And even some Crossfit trainers tend to disagree on this subject matter)
    You're not just disagreeing with my comment, you're disagreeing with actual research. The link I provided was an article published by a professor in the department of biomedical physiology and kinesiology at a university, not a trainer. I don't know that you can compare someone with a bachelors AND a masters degree to a trainer who needs nothing more than a high school certificate and 3 hours test to be a trainer. Further more, you are using someone's anecdotal evidence to support your point which doesn't fit anyway. In order to enter a catabolic state, you would have to have a severe energy deficit and you would have had to have starved yourself for a quite a while. I'm not disagreeing with the fact that there are diminishing returns with several hour long workouts but again, it's not as easy as jumping on a treadmill for 30 minutes and suddenly losing your biceps.

    I'm glad that what you're doing it working for you, I'm not attacking your methods I'm just saying that your statement wasn't entirely factually correct. And you're right, you have to do what works for you. I'm just making sure that erroneous info isn't being spread.
  • Oh, wow. I wasn't even disagreeing with the research. I skimmed through it but didn't want to waste my time reading something like that which I've read a hundred times before.

    There is a fat burning zone. Whether you spend your time walking for two hours or running for one hour to meet the same fat calorie burn. (which I'm sure your article reflected on in some form or fashion).

    And no, you can not jump on a treadmill and lose a bicep. But you can jump on a treadmill, with an empty stomach, run for an hour or two, and have some of your calorie burn come from protein/muscle.

    I do high intensity cardio workouts, but I try to keep them less than an hour. If I get in my groove and go over, I don't worry so much about it. I have a great strength training routine and I try to intake a lot of protein. (Which I mentioned in my first comment, that she shouldn't get so tied up in the percentages at this point as long as she varies her routine and adds in strength training.)

    What I disagree with is that the fat burning zone is a myth. And yes, I would tend to agree with trainers - regardless of their education - who have given myself and friends great results by having us focus more on our fat burning zones.


    Good article:

    "When your heart rate is sitting between 50 and 80 percent of its maximum, the body continues burning half carbohydrates and half fat. This 50-50 zone is called the "fat burn" zone. When you increase the intensity and your heart rate rises to between 80 and 90 percent of its maximum, your body switches into carb burn mode. In this "cardio zone," your body starts burning 85 percent carbohydrates and just 15 percent fat. If your body starts to run low on carbohydrates during these extended cardio sessions, it will begin using protein in combination with fat. Some of these protein calories come from amino acids, and some come from muscle."



    Read more: http://www.livestrong.com/article/20...#ixzz1YnwBG2hQ