Is Eating Low Carb & Training For Half Marathon Possible?

Hey just wondering how people have faired while eating low carb and half or full marathon training? I've read the body can use fat as a fuel for running as carbs are used in higher fast twitch muscle exercise...I guess this means things like sprinting as opposed to a moderate run?

Anyone else eating low carb and training for 1/2 or full marathon distances? Any challenges? Do you still carb load before long runs? How long to get into the mode where you body will use fat in lieu of the lack of carbs?

Any personal experiences or knowledge would be helpful thanks!
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Replies

  • scottb81
    scottb81 Posts: 2,538 Member
    I haven't done it but I know enough to say that it probably can be done within limitations.

    You will need to train your body to burn predominantly fat which means primarily training at a low heartrate. Training at higher intensities will need more carbs and will burn you out quickly on a low carb diet.

    Keep your runs below a heartrate of (age-50) and you will target training the body for fat burning. (Google Maffetone method).

    You will probably have to run pretty slow, especially at first, but that's ok. The training effect is there and you will get faster over time.
  • AJ_G
    AJ_G Posts: 4,158 Member
    Is it possible? Sure

    Is it a good idea? Probably not

    It's two opposing goals, I wouldn't recommend training for fat loss, and performance at the same time
  • GoldFish1326
    GoldFish1326 Posts: 81 Member
    I've run both ways, with high carbs and then with carbs mostly coming from fruits/vegetables. It was BRUTAL the first day where I had easily been running 5-6 miles now I was exhausted but then the next time it was alright again so not sure if that's a one off or the start of adjusting.

    I have an allergy to flour so I really don't eat much in the way of pasta, bread, white flour kind of things, although I love them. That's kinda where the hybrid lower carb eating came from.

    If I did my training at a slower rate and then ate more carbs on saturdays before my long runs would that possibly work? My other days I'd run but at a lower heart rate and on my longer runs I would be using carbs for energy.

    Do you think it's possible for your body to adapt to using fat for fuel so that after your carbs are burnt off you'd still have that fat burn energy or would it revert to you feeling sluggish as you've used up your carbs?
  • erickirb
    erickirb Posts: 12,294 Member
    A typically marathon runner gets 55-70% of cals from carbs. You can do it on less, yes but you will be sacrificing performance.
  • lizsmith1976
    lizsmith1976 Posts: 497 Member
    Possible but not preferable. If the half-marathon distance is something you have done many times + gone quite a bit further, then no doubt you can do it. If this is new for you and longer than what you are used to then it will be more difficult.

    How low carb do you want to go?

    I eat 40% carbs during the offseason when I am trying to cut body fat and 55% carbs during my marathon & ironman training season.

    Sensitivity to flour doesn't mean all carbs :) Sweet potatoes, white potatoes, beans, brown rice, quinoa, all other vegetables...

    Of course it's possible to adapt that way. If your body could only use stored muscle glycogen then no one would ever be able to complete an endurance event. the more endurance training you do, the better your body gets at using stored body fat for fuel. For me though, if I start out my training on a low carb diet, I can't function & perform for the time & distances that I want to go.

    You can certainly try slowing down & carb-loading on Saturdays before long runs on Sundays. Good luck testing it out. Keep notes :)
  • No_Finish_Line
    No_Finish_Line Posts: 3,661 Member
    Is it possible? Sure

    Is it a good idea? Probably not

    It's two opposing goals, I wouldn't recommend training for fat loss, and performance at the same time

    this is what i'd say. i see low carb supporting weight loss, but for optimal performance i'd think you'd need to be training and competing on a carb diet.

    if your not all about losing weight i wouldn't bother with low carb
  • motherwesser
    motherwesser Posts: 35 Member
    I am currently in the midst of my goals of a large weight loss but I am also trying to increase my performance on my new found hobby of triathlons...just 3 years into it now. I am training for an Ironman as my big goal for next year. I have a half marathon next month. I currently have my daily nutrition as balanced/moderate to attain the best of both for me now. As I get to my goal weight, the higher carb content as recommended by the other gents here is true. You may be in a similar situation as I. Currently, my daily goals are 40% carbs, 40% protein and 20% fats. I do, however, take higher carb intake around heavy training days and races.
  • holly1283
    holly1283 Posts: 741 Member
    Possible, yes. I have one question: how do you think you body will get the fuel it needs to perform running for 13+ miles? Why would you want to tax your body in such a way? Make healthy carb choices is your best bet.
  • ElliottTN
    ElliottTN Posts: 1,614 Member
    Sure but you probably won't be breaking any land speed records along your journey.
  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
    It can be done. Heck, almost anything can be done.

    Can it be done while running a competitive time? No. The human body cannot metabolize fat quickly enough to fuel an activity like running.

    So it depends on your goals.
  • srcardinal10
    srcardinal10 Posts: 387 Member
    I've done it while training for my last marathon so yes, it is possible. Are you going to hurt and feel like dying if you shoot for a competitive time -- absolutely. So my suggestion -- you do need be smart and make sure that you are getting your carbs and that they are coming from healthy sources though. You need them as fuel if you're looking to complete this without wanting to die. ;) So eat steel cut oats, yams/sweet potatoes, quinoa, ezekiel bread, etc.

    Good luck.
  • geekyjock76
    geekyjock76 Posts: 2,720 Member
    Couple a low-carb intake with the fact that the large energy demand of doing marathons will surpass your limit of 24-hour fat oxidation, where do you think energy to fuel the extra deficit will come from? A 130 lb person can burn approximately 2200 calories during a marathon.
  • Mjconnelly586
    Mjconnelly586 Posts: 41 Member
    I did that for my first half marathon. I was trying to drop lbs and wanted to increase mileage. I had some pretty miserable runs. It is hard to get up and run when you do not have the energy. Did not get a great time. Was happy to cross the finish line.

    My second and third half marathon I ate a well balanced diet and enjoyed my training and my time was MUCH better. I think that my diet had a lot to do with it. I was not looking to place or anything :)

    I would suggest eating "good carbs", have fruit, have sweet potatoes have some whole grain especially on your running days. You can still avoid white sugar and flour but give your body what it needs. Focus more on calorie deficit and having a well balanced diet vs low carb.
  • GoldFish1326
    GoldFish1326 Posts: 81 Member
    Sooooooo....it's pretty unanimous I'd be a tard to do this without upping my carb intake, done. Now if only I could turn ice cream into a healthy carb I'd be all set....

    I'm a "want to finish" the race kind of person but I'm signed up for the sub 2 hr, 1/2 marathon training group...I kind of doubt this falls into a competitive time for that race length but under 2 hrs is my goal.

    Out of curiousity what is a competitive time range for a 1/2? Purely since you've piqued my interest not because top heavy midgets like myself intend to rock out that kind of crazy training!

    RUNNING ON A TREADMILL QUESTION BELOW....

    So now let me pick your brains on something else, I live in Edmonton, Alberta....8 months of winter is what it feels like so ALOT of my Jan - March at least training will be done on a treadmill until I can get outside, anyone have experience with alot of treadmill training? (Winter running is way too hardcore for me and I've had 3 knee surgeries, not looking to slip and have another).


    Any personal experience using the treadmill for 50+ % of your training?
  • scottb81
    scottb81 Posts: 2,538 Member
    RUNNING ON A TREADMILL QUESTION BELOW....
    A lady in Alaska trained for the Olypic trials using mostly a treadmill, so it can be done.

    http://running.competitor.com/2010/12/features/treadmill-time_18361
  • srcardinal10
    srcardinal10 Posts: 387 Member
    RUNNING ON A TREADMILL QUESTION BELOW....

    So now let me pick your brains on something else, I live in Edmonton, Alberta....8 months of winter is what it feels like so ALOT of my Jan - March at least training will be done on a treadmill until I can get outside, anyone have experience with alot of treadmill training? (Winter running is way too hardcore for me and I've had 3 knee surgeries, not looking to slip and have another).


    Any personal experience using the treadmill for 50+ % of your training?

    Competitive times: Sub 2 hours

    Running on a treadmill: It can be done. Turn the incline on 1 at least to ensure that your legs are actually doing the work to simulate running on flat ground.
  • lizsmith1976
    lizsmith1976 Posts: 497 Member
    Hmm, competitive? At your age, and at a big race? Honestly - 1:30-1:35. Impressive? Sub 2 hours :)

    My half-maarthon that was sub 2 is still one of my best and happiest race days. Training for that is a lofty, and good goal.

    I train 50% on the treadmill because I live in Houston and during the summer we spend half the days in the high 90s and low 100s (36-40 for my C people). It's miserable and the heat makes me sick. I think it is great for training your mind to accept boredom and for getting in the miles. It's also good for speedwork since you can be very accurate. +1 to the above commenter who said give it some incline. Otherwise, you will be surprised at how "slow" you are when you take it back outside. I just use 1 degree incline, and I think that's enough. You can use more for "hill repeats", and use even more if you just want to be surprised at how super-fast you are when you take it back outside :)
  • GoldFish1326
    GoldFish1326 Posts: 81 Member
    RUNNING ON A TREADMILL QUESTION BELOW....
    A lady in Alaska trained for the Olypic trials using mostly a treadmill, so it can be done.

    http://running.competitor.com/2010/12/features/treadmill-time_18361

    Cool I'd heard about upping the incline sweet link thanks!
  • GoldFish1326
    GoldFish1326 Posts: 81 Member
    Hmm, competitive? At your age, and at a big race? Honestly - 1:30-1:35. Impressive? Sub 2 hours :)

    My half-maarthon that was sub 2 is still one of my best and happiest race days. Training for that is a lofty, and good goal.





    I've never had anyone say at my age...HILARIOUS! I'm glad under 2 hours is attainable that's in my wheelhouse yay. Also glad that I can use the treadmill incline to simulate outdoor conditions to some extent, I guess it's the weather outside too that you don't get used to and that could be deterimental if it psyches you out!

    I never really thought hill training could be done on the treadmill but that's good news too thanks!
  • GoldFish1326
    GoldFish1326 Posts: 81 Member
    I'm brutal at trying to reply to individual comments, I don't want to quote everything but it's slightly messed up.


    My apologizes to your eyes people but much love for all the sweet tips!

    Thanks!
  • lizsmith1976
    lizsmith1976 Posts: 497 Member
    HAHA! Apologies!

    I actually meant at your YOUNG age! You are younger than me. As you get older it gets easier to be competitive at a slower speed :) I can't wait to "age up" into the 40s. I'll be more competitive then!
  • RunBrew
    RunBrew Posts: 220 Member
    Out of curiousity what is a competitive time range for a 1/2? Purely since you've piqued my interest not because top heavy midgets like myself intend to rock out that kind of crazy training!

    http://www.pace-calculator.com/average-half-marathon-pace-by-age-sex.php

    Use the column on the right side of the page to adjust your demographics.

    Edit:
    That link will give you a per-mile pace not a total time.
    Convert the pace to time, or input a goal time to get a target pace using this link
    http://www.coolrunning.com/engine/4/4_1/96.shtml
  • GoldFish1326
    GoldFish1326 Posts: 81 Member
    HAHA! Apologies!

    I actually meant at your YOUNG age! You are younger than me. As you get older it gets easier to be competitive at a slower speed :) I can't wait to "age up" into the 40s. I'll be more competitive then!

    Awesome, that's like me and playing "classics" soccer...defeinetly an advantage once I'm at that age!
  • KathleenMurry
    KathleenMurry Posts: 448 Member
    WHY?!?!?!?!?!?!
  • GoldFish1326
    GoldFish1326 Posts: 81 Member
    Out of curiousity what is a competitive time range for a 1/2? Purely since you've piqued my interest not because top heavy midgets like myself intend to rock out that kind of crazy training!

    http://www.pace-calculator.com/average-half-marathon-pace-by-age-sex.php

    Use the column on the right side of the page to adjust your demographics.

    Edit:
    That link will give you a per-mile pace not a total time.
    Convert the pace to time, or input a goal time to get a target pace using this link
    http://www.coolrunning.com/engine/4/4_1/96.shtml

    Cool, my 10km time is under the average for my age but the further I run the slower I'll get so it's doable to be under 2 I'll just have to work a bit harder to make up for the slow down, thanks for the info!
  • lithezebra
    lithezebra Posts: 3,670 Member
    I don't see a problem, as long as you're eating enough, paying attention to how you feel, making adjustments as needed, and your goal is to run a half marathon, not win a half marathon. I eat a low carb diet at about 150 grams a day. Some people eat a low carb diet at 250 grams a day, and some people do it at 50 or less.
  • Deanna_garnermommy
    Deanna_garnermommy Posts: 118 Member
    I think you are fine as long as your body is okay with it! I am a low carber and I run!
  • wilsoje74
    wilsoje74 Posts: 1,720 Member
    How fast can you run a mile? Under 2 would be great, I don't think I could do it. I just did a 10 mile in 1:37 which is about 9:45 min miles.
  • SonicDeathMonkey80
    SonicDeathMonkey80 Posts: 4,489 Member
    I cannot imagine a life without Cheez-its and Goldfish, but best of luck to you :huh:
  • GoldFish1326
    GoldFish1326 Posts: 81 Member
    Haha yeah WIN a half marathon is not my goal, it's funny how I never even considered there being something you could win...obvs I think finishing = I'm WINNINGEST!

    Glad to hear it's possible I will still up my carbs but I won't start eating 300 carbs a day on a regular basis or anything, I'll adjust if I feel exhausted that'll be a good indicator methinks.

    I like the IDEA of cheezits, cause I love cheese but it's like mac n cheese the colour tricks me into thinking it's super cheesy and then it totally isn't...so orange dye #7 isn't my favourite food. But things like taco salad with cilantro sour cream and pico de gallo...I'd much rather have num num.