Exercise to burn fat instead of calories?

I read somewhere that if you're overweight it's good to exercise in the morning before you eat or just have a light breakfast first so that your body will burn fat stores for energy instead of calories. This morning I woke up, ate a medium sized apple, then did a workout. About 15 minutes of squats and lunges, and 30 minutes of Hip Hop Abs. For reference, I'm 5'4 and 177 lbs, and I just started working out today. I worked up a pretty good sweat but it felt good! I'm somewhat out of shape, obviously, but not totally out of shape. I still have some strength and a little endurance. So anyway, I feel pretty good now and plan on eating a good lunch now that I've worked up an appetite. I was wondering if this is a good way to go about things. Thanks. (I also drank a lot of water before and during the workout.)
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Replies

  • Cherimoose
    Cherimoose Posts: 5,208 Member
    I read somewhere that if you're overweight it's good to exercise in the morning before you eat or just have a light breakfast first so that your body will burn fat stores for energy instead of calories.

    That is an old myth.

    Any other questions?
  • kgeyser
    kgeyser Posts: 22,505 Member
    It doesn't matter what time of day you work out, or what you eat or don't eat before a workout, the results are exactly the same. Sorry. But if morning workouts work for you, there's no reason to stop doing them.
  • lisawinning4losing
    lisawinning4losing Posts: 726 Member
    Well, if it's a myth that sucks because I was really hoping it would work. Lol.

    I also read somewhere that the best time to eat carbs is before or after a workout so you'll burn them off more efficiently. Another myth?
  • editorgrrl
    editorgrrl Posts: 7,060 Member
  • Llamapants86
    Llamapants86 Posts: 1,221 Member
    Do what works for you. I hate working out first thing in the morning, it just doesn't do it for me.

    And you burn calories either way, if you have fasted (eg over night) then you get the calories from energies stores in your body (like fat) and then you eat and use calories for day to day living on the food calories. If you eat then work out the calories for your work out come from food and are no longer there so that you burn energy stores for day to day living. In the end the equation is the same.
  • stevencloser
    stevencloser Posts: 8,911 Member
    Well, if it's a myth that sucks because I was really hoping it would work. Lol.

    I also read somewhere that the best time to eat carbs is before or after a workout so you'll burn them off more efficiently. Another myth?
    Yep.
    There's 2 major things you have to think about when trying to lose fat.
    1) Eating less calories than your body needs will cause weight loss. You'll lose fat and muscle because your body needs the energy to work, so it uses up its storages.
    2) To minimize the amount of muscle loss, eat a lot of protein and do weight lifting
  • Hi,
    Thanks for that tip. But I can't lift bec of a "bad back." Would the small 2 pound weights count, or doubling up on the 2 pound weights?
  • Natmarie73
    Natmarie73 Posts: 287 Member
    I was reading about this just yesterday but damned if I can find that article again :( My personal trainer certainly advocates it though and I trust his credentials pretty highly seeing as he coaches high level state track and field athletes. He recommends an hour of cardio first thing in the morning prior to eating breakfast for quicker fat loss, his premise being that after not eating all night your muscles do not have a lot of glycogen stores to use as fuel which forces your body to burn stored fat as fuel instead. You will still be burning calories, but they will come from stored fat instead of whatever you have just eaten.

    Another article I read said that in order to burn fat the duration of the excersise should be longer than 30 minutes and your heart rate should only get to 70 - 80% of your Max HR in order to burn fat most efficiently.

    http://www.umich.edu/~medfit/resistancetraining/timingiseverything101705.html

    I have to get up at 4:00 as it is to get to work on time so getting up any earlier than that to do an hour of cardio is not going to happen but I do try to do my cardio workout first thing when I'm on R&R because a) I like to run before it gets too hot and sunny, and b) I can't run with food in my stomach anyway. If I can't do mornings I do it in the evenings before dinner.

    Whatever gets you off the couch and is sustainable to your lifestyle is better than doing nothing and yes the results will be the same no matter what time you workout but you might lose fat quicker in the mornings maybe. No harm in trying it out if it fits your schedule.
  • meshashesha2012
    meshashesha2012 Posts: 8,329 Member
    what is a "bad back" .
  • lisawinning4losing
    lisawinning4losing Posts: 726 Member
    I was reading about this just yesterday but damned if I can find that article again :( My personal trainer certainly advocates it though and I trust his credentials pretty highly seeing as he coaches high level state track and field athletes. He recommends an hour of cardio first thing in the morning prior to eating breakfast for quicker fat loss, his premise being that after not eating all night your muscles do not have a lot of glycogen stores to use as fuel which forces your body to burn stored fat as fuel instead. You will still be burning calories, but they will come from stored fat instead of whatever you have just eaten.

    Another article I read said that in order to burn fat the duration of the excersise should be longer than 30 minutes and your heart rate should only get to 70 - 80% of your Max HR in order to burn fat most efficiently.

    http://www.umich.edu/~medfit/resistancetraining/timingiseverything101705.html

    I have to get up at 4:00 as it is to get to work on time so getting up any earlier than that to do an hour of cardio is not going to happen but I do try to do my cardio workout first thing when I'm on R&R because a) I like to run before it gets too hot and sunny, and b) I can't run with food in my stomach anyway. If I can't do mornings I do it in the evenings before dinner.

    Whatever gets you off the couch and is sustainable to your lifestyle is better than doing nothing and yes the results will be the same no matter what time you workout but you might lose fat quicker in the mornings maybe. No harm in trying it out if it fits your schedule.

    Thanks. I'm also of the opinion that there's no harm in trying and since it fits into my schedule I might as well do it!
  • stevencloser
    stevencloser Posts: 8,911 Member
    Your body always burns calories just to function. That's why eating at a deficit makes you lose weight. Exercising raises that deficit.
    For better understanding, imagine your body is a bank account.
    Every day money gets transferred off it to pay for your bills throughout the day. That's the calories your body burns.
    Also throughout the day you deposit money to pay the bills. If you deposit less money than you have to pay, you have to use your savings to pay off the bills for the day. So you end up with less money after the day than you started with. That's weight loss.

    Now, if you buy a nice car early in the morning (exercise), it will still cost you the same amount of money as buying it in the evening does, and the money you used to buy it for comes back through the deposits you make in the day (eating).
    So no matter if you deposit first, then buy something, or buy it first then deposit the money, the end result will be the same.
  • Cherimoose
    Cherimoose Posts: 5,208 Member
    My personal trainer certainly advocates it though and I trust his credentials pretty highly seeing as he coaches high level state track and field athletes. He recommends an hour of cardio first thing in the morning prior to eating breakfast for quicker fat loss, his premise being that after not eating all night your muscles do not have a lot of glycogen stores to use as fuel which forces your body to burn stored fat as fuel instead.

    Sounds good in theory, but the studies disagree. A summary of the studies is here:

    http://pulsthjalfun.is/wp-content/uploads/2011/11/doescardio.pdf
    Another article I read said that in order to burn fat the duration of the excersise should be longer than 30 minutes and your heart rate should only get to 70 - 80% of your Max HR in order to burn fat most efficiently.
    http://www.umich.edu/~medfit/resistancetraining/timingiseverything101705.html

    Again, lots of good-sounding textbook theories at that link, but the studies disagree. Short exercise sessions are equal or better than long sessions:

    http://www.ncbi.nlm.nih.gov/pubmed/11601564
    http://jap.physiology.org/cgi/content/abstract/102/6/2158
    http://www.ncbi.nlm.nih.gov/pubmed/8963358

    I personally avoid long workout sessions in a fasted state, because - according to the textbook theories - it burns muscle as fuel, though a process called gluconeogenesis. I haven't found any studies on how much muscle is burned though.

    Anyway, there are no tricks or shortcuts to weight loss. Gotta eat less and/or move more.
  • fitandfortyish
    fitandfortyish Posts: 194 Member
    It doesn't matter what time of day you work out, or what you eat or don't eat before a workout, the results are exactly the same. Sorry. But if morning workouts work for you, there's no reason to stop doing them.

    There is some credible studies out there (lean gains, eat-stop-eat, Rusty Moore) who claim working out "fasted" -- min 4 hours since you last ate that seem to show better fat burning when doing HIIT...If anyone is interested in giving it a try to see if it works for you.
  • thefitnightowl
    thefitnightowl Posts: 32 Member
    It doesn't matter what time of day you work out, or what you eat or don't eat before a workout, the results are exactly the same. Sorry. But if morning workouts work for you, there's no reason to stop doing them.


    This is not true. Actually, when you work out before you eat in the morning, in a fasted state they call it, your body will burn FAT more efficiently because just like the girl in the top post said, your muscles will use the workouts to deplete any energy left in your muscles. I have done this for years and it significantly makes a different in my tummy area, where most fat is stored.
    Feel free to add me anyone!
    -Shannon
  • thefitnightowl
    thefitnightowl Posts: 32 Member
    It doesn't matter what time of day you work out, or what you eat or don't eat before a workout, the results are exactly the same. Sorry. But if morning workouts work for you, there's no reason to stop doing them.

    There is some credible studies out there (lean gains, eat-stop-eat, Rusty Moore) who claim working out "fasted" -- min 4 hours since you last ate that seem to show better fat burning when doing HIIT...If anyone is interested in giving it a try to see if it works for you.

    I completely agree with this post. Ive seen significant results from fasted morning workouts! Thanks for this!
  • thefitnightowl
    thefitnightowl Posts: 32 Member
    My personal trainer certainly advocates it though and I trust his credentials pretty highly seeing as he coaches high level state track and field athletes. He recommends an hour of cardio first thing in the morning prior to eating breakfast for quicker fat loss, his premise being that after not eating all night your muscles do not have a lot of glycogen stores to use as fuel which forces your body to burn stored fat as fuel instead.

    Sounds good in theory, but the studies disagree. A summary of the studies is here:

    http://pulsthjalfun.is/wp-content/uploads/2011/11/doescardio.pdf
    Another article I read said that in order to burn fat the duration of the excersise should be longer than 30 minutes and your heart rate should only get to 70 - 80% of your Max HR in order to burn fat most efficiently.
    http://www.umich.edu/~medfit/resistancetraining/timingiseverything101705.html

    Again, lots of good-sounding textbook theories at that link, but the studies disagree. Short exercise sessions are equal or better than long sessions:

    http://www.ncbi.nlm.nih.gov/pubmed/11601564
    http://jap.physiology.org/cgi/content/abstract/102/6/2158
    http://www.ncbi.nlm.nih.gov/pubmed/8963358

    I personally avoid long workout sessions in a fasted state, because - according to the textbook theories - it burns muscle as fuel, though a process called gluconeogenesis. I haven't found any studies on how much muscle is burned though.

    Anyway, there are no tricks or shortcuts to weight loss. Gotta eat less and/or move more.

    I also completely agree with this. A fast 20-30 minute HIIT (where you max out your heart rate 3 or 4 times in the session) will do WONDERS for your body fat %....trust me girl..... I used to be 240 pounds. I have my fair share of experience! Im super pumped you learned about this morning cardio!!
  • fitandfortyish
    fitandfortyish Posts: 194 Member
    It doesn't matter what time of day you work out, or what you eat or don't eat before a workout, the results are exactly the same. Sorry. But if morning workouts work for you, there's no reason to stop doing them.

    There is some credible studies out there (lean gains, eat-stop-eat, Rusty Moore) who claim working out "fasted" -- min 4 hours since you last ate that seem to show better fat burning when doing HIIT...If anyone is interested in giving it a try to see if it works for you.

    I completely agree with this post. Ive seen significant results from fasted morning workouts! Thanks for this!

    Me too---I dropped quite a bit of fat and no muscle so yes, i'm a huge fan, but also know it's not for everyone
  • indianarunner76
    indianarunner76 Posts: 108 Member
    From personal experience, the last four months I have done cardio first thing in morning on empty stomach and it worked out well for me. I have lost a total of 57 pounds. I did my strength training 3-4 times per week in afternoon to help maintain lean muscle mass. Definitely worth a shot. Only failure is not to try.
  • Sunbrooke
    Sunbrooke Posts: 632 Member
    I workout early in the mornings. I usually have a small smoothie and the go workout about a half hour later. I notice that if I work out on a fairly empty stomach, I can push harder on cardio and drink more water during my workout. Also, I like having a routine in the morning and i feel good the rest of the day knowing that i worked out. Ever notice many people like eating the exact same thing for breakfast, but not other meals? Everyone is different, but mornings are just good for routines.
  • lisawinning4losing
    lisawinning4losing Posts: 726 Member
    Thanks everyone for your input! I know that it's probably all the same in the long run, but after reviewing all the information, I think I'll just continue doing what I did today--only eat a piece of fruit or very light breakfast before my workout--in hopes that it will help to burn extra fat. The theory makes sense to me, but either way it couldn't hurt. :wink:
  • heybales
    heybales Posts: 18,842 Member
    Eating the fruit, the sugar, just killed the whole effect you were attempting to get.
    It only makes sense because you don't understand how the body and energy systems work.

    Eating the sugar will cause insulin to go up, and fat burning to turn off. That's what insulin does, read up on it. You eat any sugar, it goes up. You eat enough protein, it goes up. Eat fat, no. But eating butter before a workout might backfire. ;-)

    You will now burn what you ate until insulin returns to normal and fat burning is turned back on.
    In other words - you will burn NO fat on your body until back to normal. That can take from 1-4 hrs depending on meal size.

    The whole premise being doing a fasted workout (last meal night before) is your body is already in the best fat-burning state it's going to be in. It's been there the whole night.

    As soon as you start moving more, like more intense exercise, you will burn more carbs, no way around that. Go anaerobic, and it's total carbs to power the effort.

    Guess what lifting is?

    Ya, the fasted idea is for cardio, not lifting. Normally it takes about 30 min of moderate cardio for your body to settle in to the normal fat to carb ratio of energy source. Prior to that it's higher carbs used.
    The idea of fasted cardio is to jump to that state faster, right from the start, of more fat burn.

    But it must be slow cardio that was going to burn mainly fat anyway, go intense and you'll burn more carbs no matter what, you got plenty in your muscles already, just not as much in your liver for your blood sugar levels.

    But the whole thing backfires when you look at the day. You just had 1 hr say of cardio time. And you just burned say 200-300 calories less because you went so slow. So what if it was mainly fat, you would have burned the same amount of fat calories anyway going more intense, and burned more overall.
    Burning more overall would have meant after the next meal, when insulin goes up and carbs are refilled, you would have had more to refill, and insulin would have returned to normal faster, and you'd get back to normal fat burning state faster.

    That's why you burn more fat in a diet, almost always about the insulin effect being shorter and refilling carb stores. Gets you back to fat burning state faster than otherwise.

    Fasted lifting is pure preference. Some can do it, and trying to eat before early morning workout makes stomach trouble. Others feel weak and need energy.
    Since you aren't burning fat for that anaerobic effort anyway, being in fasted state provides no benefit to lifting.
  • And i was just about to ask, Is walking an efficient method for burning weight or is going to the gym better for you?
    glad i found this thread :D
  • heybales
    heybales Posts: 18,842 Member
    My personal trainer certainly advocates it though and I trust his credentials pretty highly seeing as he coaches high level state track and field athletes. He recommends an hour of cardio first thing in the morning prior to eating breakfast for quicker fat loss, his premise being that after not eating all night your muscles do not have a lot of glycogen stores to use as fuel which forces your body to burn stored fat as fuel instead. You will still be burning calories, but they will come from stored fat instead of whatever you have just eaten.

    Fire your trainer, he/she's a goof ball.

    If you accurately stated what they said, that implies a belief your muscle glycogen stores can be used for general blood sugar use, general energy use through the night, and will be depleted enough in the morning to make any difference.

    Your muscle glycogen stores can only be used locally by the muscle - they cannot be put into the blood stream for use anywhere else.

    Only the liver stores can.

    And your liver stores topped off can generally make it through 10-12 of sleep providing the brain energy in blood sugar.

    Your level of exercise, the intensity, is going to dictate what the ratio of carbs to fat as energy source is going to be, with a slightly higher carb focus for first 30 min of easy cardio until normal ratio is hit.
  • Dewymorning
    Dewymorning Posts: 762 Member
    A calorie is a unit of energy.

    Fat is a substance which the body can convert into energy, at approximately 3500 calories per pound.

    I am confused.
  • fitandfortyish
    fitandfortyish Posts: 194 Member
    A calorie is a unit of energy.

    Fat is a substance which the body can convert into energy, at approximately 3500 calories per pound.

    I am confused.

    I'm not a huge expert but tend to prefer working out fasted so I'll try to explain some of it for you--hopefully if I screw up a detail someone will correct me...

    Yes, what you say is right--at some level when you exercise really shouldn't matter because you are burning the same amount of calories at 8am as you would at 8pm. A calorie, is a calorie afterall. Working out fasted ---first thing in the morning after not eating since dinner the night before, or 4 hours after your last meal in the afternoon, forces your body to "take" energy from fat.

    You may have read on this board that foods, especially carbs, are energy. When you body doesn't use up all available energy, it stores it as fat. Conversely, if you just eat something and go work out, your body will grab that energy first and use it, because your body doesn't need to 'pull' energy from it's stored resources.

    So the logic here is if the body doesn't have readily available energy it will burn up stored fat to fuel your exercise.

    People who are lean already, don't have much stored fats and can run into trouble because the body will start to break down muscle (protein) to fuel itself. Which is why you will see posts about protein balance etc.

    At the end of the day, calories burned are calories burned like you say--and you will lose weight for sure. But if you body is pulling from its fat reserves to fuel -- then a person *should* see a decrease in their overall body fat %---keep in mind that you must not put an excessive amount of carb back into your system for the rest of the day, or you just end up putting back what you took out.

    I want to add here that I DO NOT advocate low carbs diets for myself. I love me my carbs, I just keep my carb intake at only 10% of my daily calorie intake.

    Did I make that more confusing ... or less??
  • richardheath
    richardheath Posts: 1,276 Member
    Did I make that more confusing ... or less??

    More.

    Yes, the body will burn fat if you exercise fasted. However, the body will also burn fat if you don't exercise at all and are in a calorie deficit.

    Exercise isn't needed for weight loss - a calorie deficit is all that your body requires. Exercise (in terms of weight loss) just increases the amount you can eat and still have a deficit.

    In terms of ensuring the most of your weight loss is fat, the very best thing you can do is to lift weights (some form of resistance training) and eat sufficient protein at an overall calorie deficit. This will help preserve lean body mass (i.e muscle) while shedding weight (i.e fat). Meal timing is essentially irrelevant for anyone but the elite athletes.

    Don't over complicate things. Eat when it suits you. Exercise when you can. If you are tired, have a few "quick" carbs before or after. If not, don't...

    For the record - I usually exercise first thing in the morning and rarely eat beforehand. But that is just because I don't like to eat that early. I have a protein shake afterwards, and consider that "breakfast".
  • richardheath
    richardheath Posts: 1,276 Member
    Hi,
    Thanks for that tip. But I can't lift bec of a "bad back." Would the small 2 pound weights count, or doubling up on the 2 pound weights?

    Talk to a physical therapist. It really depends on how bad your back is, and we can't diagnose that.

    But in general, a 2 lb weight is not considered "weight lifting" for most people. Weight lifting would be a weight you can just do 3-5 reps for 3-5 sets (for strength building. also known as "heavy lifting") or 10-12 reps by 3-5 sets for sarcoplasmic hypertrophy. Any more reps than that and it's cardio/endurance, not strength. {Not that that is bad, it's just not weight lifting.]
  • urban_ninja
    urban_ninja Posts: 175 Member
    I was curious about this so I did an internet search and found this article.

    http://www.jillianmichaels.com/fit/lose-weight/myth-empty-stomach-workouts?xid=nl_LosingItWithJillianMichaels_20140203

    This makes sense to me. I usually grab a little food before a workout in the morning so I was looking for validation.
  • Dewymorning
    Dewymorning Posts: 762 Member
    A calorie is a unit of energy.

    Fat is a substance which the body can convert into energy, at approximately 3500 calories per pound.

    I am confused.

    I'm not a huge expert but tend to prefer working out fasted so I'll try to explain some of it for you--hopefully if I screw up a detail someone will correct me...

    Yes, what you say is right--at some level when you exercise really shouldn't matter because you are burning the same amount of calories at 8am as you would at 8pm. A calorie, is a calorie afterall. Working out fasted ---first thing in the morning after not eating since dinner the night before, or 4 hours after your last meal in the afternoon, forces your body to "take" energy from fat.

    You may have read on this board that foods, especially carbs, are energy. When you body doesn't use up all available energy, it stores it as fat. Conversely, if you just eat something and go work out, your body will grab that energy first and use it, because your body doesn't need to 'pull' energy from it's stored resources.

    So the logic here is if the body doesn't have readily available energy it will burn up stored fat to fuel your exercise.

    People who are lean already, don't have much stored fats and can run into trouble because the body will start to break down muscle (protein) to fuel itself. Which is why you will see posts about protein balance etc.

    At the end of the day, calories burned are calories burned like you say--and you will lose weight for sure. But if you body is pulling from its fat reserves to fuel -- then a person *should* see a decrease in their overall body fat %---keep in mind that you must not put an excessive amount of carb back into your system for the rest of the day, or you just end up putting back what you took out.

    I want to add here that I DO NOT advocate low carbs diets for myself. I love me my carbs, I just keep my carb intake at only 10% of my daily calorie intake.

    Did I make that more confusing ... or less??

    So, I eat in the morning, and my body burns energy from my fat. I then eat breakfast. For the rest of the day from when I ate breakfast I eat more calories than I burn. So what does my body do with the excess calories?

    I think the answer is, store them as fat.

    So....

    I think I will stick with my current routine.

    I do usually exercise just before I eat my lunch, but that is just because exercising straight after eating gives me cramps.
  • heybales
    heybales Posts: 18,842 Member
    So the logic here is if the body doesn't have readily available energy it will burn up stored fat to fuel your exercise.

    People who are lean already, don't have much stored fats and can run into trouble because the body will start to break down muscle (protein) to fuel itself. Which is why you will see posts about protein balance etc.

    Most of that was pretty good, there are the 2 that need some clarification.

    The reason for muscle breakdown isn't because of lack of fat. Lack of carbs.
    Your 140 lb 5% BF marathon runner, considering 3% is vital, has 2% available, or 4.2 lbs, or 14,700 calories available for energy needs. No, they have enough fat to run several marathons in a row.

    The breakdown comes from 2 places.
    Your liver stores got depleted enough your body is going to maintain blood sugar levels, so it turns on gluconeogenesis for any available amino acids to maintain that, and some are broken down from normal muscle repair and usage. That's minor, starts happening after 60-90 min depending on your intensity or available stores prior to exercise.
    The big one is when your muscles run out of glycogen stores. That's the "wall" of your recreational marathoner that went out faster than they should have, and carb burning ratio was too high, using them up. That's your 3 or more hour range.
    Hit the wall, you still got fat that is being burned, but for the pace you were trying to do, more carbs needed, and gluconeogenesis is too slow to provide them all, so you body slows way down to compensate. That's the big muscle burner if you try to keep a strong pace maxing out that process.

    That same effect can be obtained too in a diet, where muscle glycogen stores are always at some level of depletion compared to where they could be. That's some of the big water weight loss starting a diet. Less stored with water.
    But you do several days of intense effort in a row, never replenishing enough carbs for that storage, by the end of several days, you can be in exactly the same state.

    And you can mimic the first effect too by doing intense cardio fasted. Liver stores already low, you finish them off in first 30 min, and after that some protein use is coming in to play.

    You can train your body through your type of workouts to use more fat as fuel at higher intensity levels though. It is indeed with low intensity fasted cardio. But that's a low calorie burner, and most want to optimize their time if not training for an endurance event.

    But going in to a workout fasted won't change the needed ratio. If you aren't providing enough oxygen for a certain level of fat to be used as the fuel source, carbs will be used.
    Actually, as soon as you start exercising, the ratio is usually around 80% fat usage, mid-aerobic zone it's about 50%, and at lactate threshold going anaerobic it's 0%.

    If you went into a HIIT routine fasted, and pushed it to the anaerobic zone because you are doing it correctly - you are using total carbs, no way around that.

    The only thing the fasted helps with is about the first 30 min of medium intensity cardio, where you might start out say 30% fat uses that eventually settles down to the normally expected 50%.

    So your 250-300 cal burn for that 30 min is 125-150 calories of fat, compared to unfasted 75-90 calories of fat normally.

    A difference of 50-60 calories. Fat is 9 calories per gram, so 50-60 / 9 = 5.6-6.7 grams of fat burned off extra.

    That's 0.2 - 0.24 ounces of extra fat you burned off because of that difference.

    And that's exactly why you shouldn't just look at the narrow window of the workout, but the whole day effect.

    If you had a bite to eat to allow you to do a more intense workout, you'd burn more carbs from your muscle and liver stores.
    After your next meal those will be replenished first, along with using that food for energy right then.

    Guess what happens if you have a lot of carb stores to refill? Blood sugar drops back to normal faster than if you ate a normal bigger meal, and you are back in to fat burning mode faster until your next meal.

    That's where the real fat burning comes in - the after effects.

    Like it's mentioned with lifting. Same thing in a diet, you store the less than normal carbs faster, return to fat burning mode faster. And now your body is repairing the muscles from your workout, which elevates metabolism to do so.