Fasted cardio?

Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

Replies

  • stanmann571
    stanmann571 Posts: 5,727 Member
    The only way fasted cardio is going to make you lose weight faster is if you do it first thing in the morning instead of eating breakfast. And don't otherwise adjust your eating.
  • sijomial
    sijomial Posts: 19,809 Member
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.
  • ap1972
    ap1972 Posts: 214 Member
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    ap1972 wrote: »
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

    If someone has a 500 calorie deficit and trains fasted and the next person also has a 500 calorie deficit and trains fueled, they're going to both lose about 1 Lb per week...net fat loss won't be any different. The fuel you're using for a particular activity is irrelevant as you are always cycling between fat oxidation and storage...your net fat loss is going to come down to your deficit.

  • ap1972
    ap1972 Posts: 214 Member
    cwolfman13 wrote: »
    ap1972 wrote: »
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

    If someone has a 500 calorie deficit and trains fasted and the next person also has a 500 calorie deficit and trains fueled, they're going to both lose about 1 Lb per week...net fat loss won't be any different. The fuel you're using for a particular activity is irrelevant as you are always cycling between fat oxidation and storage...your net fat loss is going to come down to your deficit.

    Isn't that assuming all weight loss is fat though?
    What about those maintaining the same weight? Would they be able to lose fat in this way?
    Would it not be possible in that scenario for 2lbs of fat to be lost and a lb of muscle gained?

    Only asking out of curiosity rather than to prove people wrong as I am certainly not an expert.
  • Finafoshizzle93
    Finafoshizzle93 Posts: 157 Member
    Yeah, obviously the calorie deficit is what causes the weight loss. More curious about the makeup I guess of the weight lost (maintaining muscle/losing fat).
  • stanmann571
    stanmann571 Posts: 5,727 Member
    ap1972 wrote: »
    cwolfman13 wrote: »
    ap1972 wrote: »
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

    If someone has a 500 calorie deficit and trains fasted and the next person also has a 500 calorie deficit and trains fueled, they're going to both lose about 1 Lb per week...net fat loss won't be any different. The fuel you're using for a particular activity is irrelevant as you are always cycling between fat oxidation and storage...your net fat loss is going to come down to your deficit.

    Isn't that assuming all weight loss is fat though?
    What about those maintaining the same weight? Would they be able to lose fat in this way?
    Would it not be possible in that scenario for 2lbs of fat to be lost and a lb of muscle gained?

    Only asking out of curiosity rather than to prove people wrong as I am certainly not an expert.

    It's possible, but unlikely.

    You might change it from .7 lb of fat lost and .3 lb of lean mass lost to .72 or even .8 lb of fat lost and .2 lb of lean mass lost, but You're not going to change it from .7 lb of fat lost and .3 lb of lean mass lost to 2 lb fat lost 1 lb lean mass gained.
  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    Yeah, obviously the calorie deficit is what causes the weight loss. More curious about the makeup I guess of the weight lost (maintaining muscle/losing fat).

    Doesn't really matter for that...your overall diet, adequate calories, adequate protein, and resistance training is going to result in maintaining more muscle mass while you lose weight so that more of your weight loss would be fat vs muscle.


    ap1972 wrote: »
    cwolfman13 wrote: »
    ap1972 wrote: »
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

    If someone has a 500 calorie deficit and trains fasted and the next person also has a 500 calorie deficit and trains fueled, they're going to both lose about 1 Lb per week...net fat loss won't be any different. The fuel you're using for a particular activity is irrelevant as you are always cycling between fat oxidation and storage...your net fat loss is going to come down to your deficit.

    Isn't that assuming all weight loss is fat though?
    What about those maintaining the same weight? Would they be able to lose fat in this way?
    Would it not be possible in that scenario for 2lbs of fat to be lost and a lb of muscle gained?

    Only asking out of curiosity rather than to prove people wrong as I am certainly not an expert.

    I've been in maintenance for 5 years and that hasn't been my experience. I've recomped (lose fat/build muscle) over that time very slowly...mostly a result of the work I do in the weight room. I cycle as well for my cardiovascular work...I do fasted in the summer because I ride early and fueled most other times of the year...haven't noticed any perceivable difference.
  • sijomial
    sijomial Posts: 19,809 Member
    ap1972 wrote: »
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

    @ap1972

    No that's not how it works, you don't use fuels sequentially. People look at the exercising muscle and ignore the total body expenditure....

    In reality for the vast majority of the time you are exercising you are using a blend of fuels and that blend is dependant on exercise intensity primarily. The lower the activity / exercise the higher proportion of fat is being used (but remember a low calorie burn rate).
    Gentle zone 3 is about 50/50 fat and carbs for me for example - my all day cycling pace.

    As you have enough carbs onboard in the form of glycogen (muscle and liver mostly) for about two hours intense exercise it's pretty irrelevant for the majority of people whether you are fasted or not.
    And if you have ever bonked (complete glycogen depletion) you would know that at that point exercise stops with crushing fatigue and mental confusion!
    I don't fuel any bike rides under two hours, it just fits in my day. It's only for rides approx 60 miles and over I get serious about more precise fuelling.

    What fasted cardio can do is make you better at fasted cardio as you do adapt to it. But still weight loss is down to calories not fuels. For weight loss it doesn't matter when you ingested your carb/fat fuels, just now, today, yesterday, last week - same as filling up your car's fuel tank the fuel level depends on the amount of fuel put in and fuel used, not when you topped up.


  • jolley07
    jolley07 Posts: 22 Member
    I've been on keto for a month now. I started intermittent fasting about 3 weeks ago and I feel amazing. 3 days ago I started running with my dog during my fast and I feel even better.
  • ap1972
    ap1972 Posts: 214 Member
    sijomial wrote: »
    ap1972 wrote: »
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

    @ap1972

    No that's not how it works, you don't use fuels sequentially. People look at the exercising muscle and ignore the total body expenditure....

    In reality for the vast majority of the time you are exercising you are using a blend of fuels and that blend is dependant on exercise intensity primarily. The lower the activity / exercise the higher proportion of fat is being used (but remember a low calorie burn rate).
    Gentle zone 3 is about 50/50 fat and carbs for me for example - my all day cycling pace.

    As you have enough carbs onboard in the form of glycogen (muscle and liver mostly) for about two hours intense exercise it's pretty irrelevant for the majority of people whether you are fasted or not.
    And if you have ever bonked (complete glycogen depletion) you would know that at that point exercise stops with crushing fatigue and mental confusion!
    I don't fuel any bike rides under two hours, it just fits in my day. It's only for rides approx 60 miles and over I get serious about more precise fuelling.

    What fasted cardio can do is make you better at fasted cardio as you do adapt to it. But still weight loss is down to calories not fuels. For weight loss it doesn't matter when you ingested your carb/fat fuels, just now, today, yesterday, last week - same as filling up your car's fuel tank the fuel level depends on the amount of fuel put in and fuel used, not when you topped up.


    Interesting you can go for 2 hours in a fasted state, when I was cycling regularly I would start to suffer after an hour or so. If I have breakfast before my ride that point would probably be 30-45 mins later so I would generally fuel as I went for anything over an hour unless I was trying to improve my fasted state performance. In those days cycling was primarily for fun and not for weight loss so I wasn't even considering whether it had an impact on burning fat.

    The car analogy is a little off as the fuel tank (Our stomach) is the only source of fuel and cannot be allowed to run out whereas our body uses energy stored in multiple ways all of which are replenished in different ways.

    If you exercise in a fasted state and burn 1000 calories causing a loss of 0.2 lb of fat and then eat 1000 calories when and how does that fat get replaced?
  • ap1972
    ap1972 Posts: 214 Member
    ap1972 wrote: »
    cwolfman13 wrote: »
    ap1972 wrote: »
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

    If someone has a 500 calorie deficit and trains fasted and the next person also has a 500 calorie deficit and trains fueled, they're going to both lose about 1 Lb per week...net fat loss won't be any different. The fuel you're using for a particular activity is irrelevant as you are always cycling between fat oxidation and storage...your net fat loss is going to come down to your deficit.

    Isn't that assuming all weight loss is fat though?
    What about those maintaining the same weight? Would they be able to lose fat in this way?
    Would it not be possible in that scenario for 2lbs of fat to be lost and a lb of muscle gained?

    Only asking out of curiosity rather than to prove people wrong as I am certainly not an expert.

    It's possible, but unlikely.

    You might change it from .7 lb of fat lost and .3 lb of lean mass lost to .72 or even .8 lb of fat lost and .2 lb of lean mass lost, but You're not going to change it from .7 lb of fat lost and .3 lb of lean mass lost to 2 lb fat lost 1 lb lean mass gained.

    Thanks, I realised the example I gave would be dramatically more than was likely but interesting that the possible difference would be so marginal
  • Azdak
    Azdak Posts: 8,281 Member
    My only addition, given how many times this subject has been discussed, is to remember that what happens in the body as an acute response to exercise is temporary, not permanent. Your body runs 24/7/365/life—what happens during the 60 or so minutes you work out is just a blip on the metabolic radar. So even if all the myths about fasted cardio were true, the overall effect would still be insignificant.
  • DancingMoosie
    DancingMoosie Posts: 8,619 Member
    I do fasted cardio every morning. I have lost, maintained, and gained weight. I don't think it matters..
  • Whey115
    Whey115 Posts: 73 Member
    I do fasted cardio every morning. I have lost, maintained, and gained weight. I don't think it matters..

    Same, I never really saw a correlation.
  • gamerbabe14
    gamerbabe14 Posts: 876 Member
    I enjoy fasted cardio just bc I don't feel as sluggish. I haven't seen it drastically impact my loss.
  • sijomial
    sijomial Posts: 19,809 Member
    ap1972 wrote: »
    sijomial wrote: »
    ap1972 wrote: »
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

    @ap1972

    No that's not how it works, you don't use fuels sequentially. People look at the exercising muscle and ignore the total body expenditure....

    In reality for the vast majority of the time you are exercising you are using a blend of fuels and that blend is dependant on exercise intensity primarily. The lower the activity / exercise the higher proportion of fat is being used (but remember a low calorie burn rate).
    Gentle zone 3 is about 50/50 fat and carbs for me for example - my all day cycling pace.

    As you have enough carbs onboard in the form of glycogen (muscle and liver mostly) for about two hours intense exercise it's pretty irrelevant for the majority of people whether you are fasted or not.
    And if you have ever bonked (complete glycogen depletion) you would know that at that point exercise stops with crushing fatigue and mental confusion!
    I don't fuel any bike rides under two hours, it just fits in my day. It's only for rides approx 60 miles and over I get serious about more precise fuelling.

    What fasted cardio can do is make you better at fasted cardio as you do adapt to it. But still weight loss is down to calories not fuels. For weight loss it doesn't matter when you ingested your carb/fat fuels, just now, today, yesterday, last week - same as filling up your car's fuel tank the fuel level depends on the amount of fuel put in and fuel used, not when you topped up.


    Interesting you can go for 2 hours in a fasted state, when I was cycling regularly I would start to suffer after an hour or so. If I have breakfast before my ride that point would probably be 30-45 mins later so I would generally fuel as I went for anything over an hour unless I was trying to improve my fasted state performance. In those days cycling was primarily for fun and not for weight loss so I wasn't even considering whether it had an impact on burning fat.

    The car analogy is a little off as the fuel tank (Our stomach) is the only source of fuel and cannot be allowed to run out whereas our body uses energy stored in multiple ways all of which are replenished in different ways.

    If you exercise in a fasted state and burn 1000 calories causing a loss of 0.2 lb of fat and then eat 1000 calories when and how does that fat get replaced?
    Ref the bold.....
    From your next meal.
    You are shuttling fat into storage and taking it out of storage multiple times a day. It's the balance that matters.

    It's part of the reason to look outside the exercise period and put it in context of the day/week/month.


  • heybales
    heybales Posts: 18,842 Member
    edited March 2018
    ap1972 wrote: »
    sijomial wrote: »
    ap1972 wrote: »
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

    @ap1972

    No that's not how it works, you don't use fuels sequentially. People look at the exercising muscle and ignore the total body expenditure....

    In reality for the vast majority of the time you are exercising you are using a blend of fuels and that blend is dependant on exercise intensity primarily. The lower the activity / exercise the higher proportion of fat is being used (but remember a low calorie burn rate).
    Gentle zone 3 is about 50/50 fat and carbs for me for example - my all day cycling pace.

    As you have enough carbs onboard in the form of glycogen (muscle and liver mostly) for about two hours intense exercise it's pretty irrelevant for the majority of people whether you are fasted or not.
    And if you have ever bonked (complete glycogen depletion) you would know that at that point exercise stops with crushing fatigue and mental confusion!
    I don't fuel any bike rides under two hours, it just fits in my day. It's only for rides approx 60 miles and over I get serious about more precise fuelling.

    What fasted cardio can do is make you better at fasted cardio as you do adapt to it. But still weight loss is down to calories not fuels. For weight loss it doesn't matter when you ingested your carb/fat fuels, just now, today, yesterday, last week - same as filling up your car's fuel tank the fuel level depends on the amount of fuel put in and fuel used, not when you topped up.


    Interesting you can go for 2 hours in a fasted state, when I was cycling regularly I would start to suffer after an hour or so. If I have breakfast before my ride that point would probably be 30-45 mins later so I would generally fuel as I went for anything over an hour unless I was trying to improve my fasted state performance. In those days cycling was primarily for fun and not for weight loss so I wasn't even considering whether it had an impact on burning fat.

    The car analogy is a little off as the fuel tank (Our stomach) is the only source of fuel and cannot be allowed to run out whereas our body uses energy stored in multiple ways all of which are replenished in different ways.

    If you exercise in a fasted state and burn 1000 calories causing a loss of 0.2 lb of fat and then eat 1000 calories when and how does that fat get replaced?

    That 2 hr reference wasn't to fasted like overnight, but just what people normally have available in fed state.

    That's the 2 hr "hitting the wall" in marathons or bonking on rides when you go out too hard, and have more to do.
    The pro's and those experienced know that pace that uses just enough glucose stores and fat as source to make it the distance/time.
    And they won't do a race fasted of course, perhaps light breakfast.

    That being said, I have done an almost 2 hr ride in evening after not eating since prior midnight, very sedentary desk job though, and barely made it. But wasn't near race speed either. Definition of fun & fast is very flexible at those times.
  • ap1972
    ap1972 Posts: 214 Member
    sijomial wrote: »
    ap1972 wrote: »
    sijomial wrote: »
    ap1972 wrote: »
    sijomial wrote: »
    Anyone have any anecdotal success with "faster" fat loss by incorporating fasted cardio?

    That's not how fat loss works.
    The fuel you use during exercise or whether that exercise is partially fuelled from food just eaten or eaten and stored at some point in the past isn't what's important - it's your long term calorie balance.

    If training fasted suits you then great, it gives you more scheduling options, some people may feel and perform better.

    If it doesn't suit you then your exercise performance and calorie burn from your exercise will also drop.

    I saw something on You Tube recently suggesting Fasted Cardio increased results and it reminded me of something I read 20 years ago and would so do it occasionally mainly due to preferring not to eat first thing rather than for any expected benefit

    Now my understanding of how we fuel exercise is limited but don't we use carbs from muscle first then from the stomach and then from fat stores? If that is correct (More than happy to be stood corrected) then if you are able to work out for long enough then wouldn't there be extra fat loss if in a fasted state? I know from cycle rides my performance would drop if I don't take on fuel during the ride so I certainly try and avoid that state now.

    @ap1972

    No that's not how it works, you don't use fuels sequentially. People look at the exercising muscle and ignore the total body expenditure....

    In reality for the vast majority of the time you are exercising you are using a blend of fuels and that blend is dependant on exercise intensity primarily. The lower the activity / exercise the higher proportion of fat is being used (but remember a low calorie burn rate).
    Gentle zone 3 is about 50/50 fat and carbs for me for example - my all day cycling pace.

    As you have enough carbs onboard in the form of glycogen (muscle and liver mostly) for about two hours intense exercise it's pretty irrelevant for the majority of people whether you are fasted or not.
    And if you have ever bonked (complete glycogen depletion) you would know that at that point exercise stops with crushing fatigue and mental confusion!
    I don't fuel any bike rides under two hours, it just fits in my day. It's only for rides approx 60 miles and over I get serious about more precise fuelling.

    What fasted cardio can do is make you better at fasted cardio as you do adapt to it. But still weight loss is down to calories not fuels. For weight loss it doesn't matter when you ingested your carb/fat fuels, just now, today, yesterday, last week - same as filling up your car's fuel tank the fuel level depends on the amount of fuel put in and fuel used, not when you topped up.


    Interesting you can go for 2 hours in a fasted state, when I was cycling regularly I would start to suffer after an hour or so. If I have breakfast before my ride that point would probably be 30-45 mins later so I would generally fuel as I went for anything over an hour unless I was trying to improve my fasted state performance. In those days cycling was primarily for fun and not for weight loss so I wasn't even considering whether it had an impact on burning fat.

    The car analogy is a little off as the fuel tank (Our stomach) is the only source of fuel and cannot be allowed to run out whereas our body uses energy stored in multiple ways all of which are replenished in different ways.

    If you exercise in a fasted state and burn 1000 calories causing a loss of 0.2 lb of fat and then eat 1000 calories when and how does that fat get replaced?
    Ref the bold.....
    From your next meal.
    You are shuttling fat into storage and taking it out of storage multiple times a day. It's the balance that matters.

    It's part of the reason to look outside the exercise period and put it in context of the day/week/month.


    Thanks :smile:

    Interesting that we cycle the fat in our bodies like that
  • ValeriePlz
    ValeriePlz Posts: 517 Member
    I do my runs fasted (or maybe with a protein shake) because it helps me avoid stomach cramping, but I agree with others that it is not shown to help with weight loss.
  • Cbean08
    Cbean08 Posts: 1,092 Member
    I eat before I workout in the morning. I'm focusing mostly on strength and speed goals right now. I feel like having the food in my stomach about an hour and a half before I work out help push me through. But, I'm not a big dinner eater, so I wake up feeling pretty empty.
  • colors_fade
    colors_fade Posts: 464 Member
    Fasted cardio literally makes no difference. The caloric deficit is what matters.

    https://www.youtube.com/watch?v=IEbWdoceH-A
  • Jthanmyfitnesspal
    Jthanmyfitnesspal Posts: 3,522 Member
    I have to say that MFPers (which includes me) are a self selected bunch who all believe in mean caloric deficit/surplus (CICO), period.

    There are several important factors not captured in this mantra:

    - Controlling intake means controlling appetite. Fasted exercise and fasting in general can be instrumental in controlling appetite. I find that cardo dulls mine and I eat less afterward (so long as I don't wait too long). (Eating low carb can also help control appetite.)

    - Energy level. Exercising fasted in the morning can have an effect on energy level both during and after exercise. I personally get a huge energy boost from morning fasted exercise (when I do it, which isn't often enough). But, this only works for sub 60min efforts. Longer workouts (like a 2 hour bike ride) benefit incredibly from eating carbs beforehand or during.

    So, CICO rules but so are feelings. You should do what makes you feel your best overall and makes it easiest to attain your goals. It is worth experimenting with a range of approaches. (I would like to experiment with exercising in the morning, for example.)
  • nhorton5
    nhorton5 Posts: 32 Member
    I only do cardio fasted as it's first thing in the morning and I couldn't manage to get up any earlier to eat
  • AnvilHead
    AnvilHead Posts: 18,343 Member
    nhorton5 wrote: »
    I only do cardio fasted as it's first thing in the morning and I couldn't manage to get up any earlier to eat

    To be clear, there's nothing wrong with doing fasted cardio. If it fits your schedule best or works best for your eating habits or whatever, that's perfectly fine. The error comes in people thinking that it somehow has magical properties that make it superior to non-fasted cardio.
  • Jthanmyfitnesspal
    Jthanmyfitnesspal Posts: 3,522 Member
    AnvilHead wrote: »
    nhorton5 wrote: »
    I only do cardio fasted as it's first thing in the morning and I couldn't manage to get up any earlier to eat

    To be clear, there's nothing wrong with doing fasted cardio. If it fits your schedule best or works best for your eating habits or whatever, that's perfectly fine. The error comes in people thinking that it somehow has magical properties that make it superior to non-fasted cardio.

    What if it helped you to control you appetite? That's a kind of magic.
  • AnvilHead
    AnvilHead Posts: 18,343 Member
    AnvilHead wrote: »
    nhorton5 wrote: »
    I only do cardio fasted as it's first thing in the morning and I couldn't manage to get up any earlier to eat

    To be clear, there's nothing wrong with doing fasted cardio. If it fits your schedule best or works best for your eating habits or whatever, that's perfectly fine. The error comes in people thinking that it somehow has magical properties that make it superior to non-fasted cardio.

    What if it helped you to control you appetite? That's a kind of magic.

    I figured that was implicit in "fits your schedule best or works best for your eating habits".