What I’ve learned from glycogen depletion runs

Is it ever ok to go running on an empty stomach. Yes, if you know how.I’ve written a few times about my experimentation this training cycle with glycogen depletion (GD) runs to teach my body to tap into fat for fuel. Without having run my marathon yet, the jury is still out on the results. However, I’ve learned plenty new about how much and what type of fueling my body prefers from this trial and error.

I think in total, I did about six or seven GD runs. After the first couple, and as my runs became longer, I did them on an alternating weekly basis. My shortest (the first) was a 16-miler, and my longest was a 20. Truthfully, I never really intended to get up to a 20 without fuel, but decided that week to just give it a try. I surprised myself by feeling good enough to make it through without fuel that day.

So what have I learned? That I used to eat too much before and during long runs. I guess I was always afraid of bonking, but I discovered that I actually feel better on

Coffee is my new best friend

less fuel. The long runs where I ate as much as I used to and then fueled as often as I used to were not my best runs (a couple were downright crappy, in fact). My best long runs this training cycle were those in a glycogen depleted state, or when I ate far less than I did in the past.

I also learned that coffee is my new favorite training partner. Again, fear of the outcome (ahem, the literal outcome) prevented me from ever trying coffee before a long run. When Mark Cucuzzella recommended I try it before a GD run, however, I gave it a go. Now I know that it provides me with loads of fuel for a long run. I think it also allows me to stay strong on less fuel both before and during my runs. So marathon day, I will have a cup of coffee, something I’ve never done in a long race before.

The bottom line–I’m very happy I tried GD long runs. They are going to be my mainstay from now on, with the exception of the really long ones and those closest to marathon dates so that I can keep my system accustomed to gels for race days.

Do you have your long-run fueling perfected or are you still working on it? 

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  1. says

    I hate coffee…I think I’m the only one on the planet. I drink black tea sometimes before a run, but I really never get a buzz from it. Glad the GD experiment was a good one for you! Do you plan to use any fueling in the marathon at CIM?
    Jill recently posted..ChicagoMy Profile

  2. says

    I’ve thought about trying coffee before a long run but have been too scared! So…you haven’t had any “issues”? How long before you run do you drink it? So interesting about your better runs being the GD ones.
    GreenGirlRunning recently posted..Posting SignsMy Profile

  3. says

    I’m still working on fueling my long runs. Earlier this year I realized I was eating too much before long runs and with making just a few small changes with the when and how much I eat I notice an improvement. My husband is a big fan of GD runs! Maybe it’s time for me to give it a try before I start training for my first 50K :)
    Jill @ Fitness, Health and Happiness recently posted..Transitioning to Natural Running Part 1My Profile

  4. says

    It’s been interesting following along with your posts on this topic. I’ve actually myself never been a “before long run big eater” and seem to usually do fine. I do carb the 2 days before but not anything massive and then the day of the run I only have some morning coffee and then a gel or two along the long run if I’m going beyond an hour of running. I have now eaten a few bits of Quaker Oats granola bars before my last two races and that is only because standing around race day waiting for the start always takes so darn long and I get hungry! But generally, while I have never tried GD runs, I do find I run just fine on a “less food” approach too. In fact, I have always felt better running on an empty stomach. However, I still have to run my first full marathon next year so I’m sure I will need to consume more as I’m not as experienced yet with going beyond 13 :) You will be proud, I’m now in Newtons … working my way down in heel-to-toe drop!!!
    Christina recently posted..Weekend update: first Newton Gravity run and a GNC winMy Profile

  5. says

    I always drink coffee in the morning before runs, but I never really thought about the benefits of it, i just drink it out of habit. It is because of your GD posts that I have quit relying on GU during runs. Somehow I had started using it on nearly all runs out of habit two miles in I would eat one, even just to get me through a 7 mile run. HA! I was scared about how I would feel since I was so used to it, but I think it was more mental really, now I plan to train for a half without using any. I have been feeling great on my runs and just hydrate when I feel low on energy and it seems to help.
    Christy@ My Dirt Road Anthem recently posted..Things You Wanted to KnowMy Profile

  6. says

    I’m definitely still working on it! I’m curious about coffee, too… I’ve never tried it because I generally only have it once or twice a week, and I usually feel the “crash” coming off it a few hours later… but maybe I”ll add that to my experimenting the next few weeks.
    Laura recently posted..An Unconventional Marathon Training PlanMy Profile

  7. says

    I am glad that the GD concept worked for you! I almost think I do something similar without even trying it. On long run days I don’t eat much breakfast, but have at least a cup of coffee. I do eat, just not a full bowl of oatmeal like usual. If I am running 20 miles I will usually only take 1-2 gels with me. The 2nd gel is just a safety net, I have never used it and the first gel I won’t take until around mile 11 or 12. When I get done working out whether its running or lifting I am rarely hungry. Other than some chocolate milk I don’t eat a meal for at least an hour. I think that this also helps settle my stomach.
    Tasha @ Healthy Diva recently posted..Weekend in Pictures & #ErikaDIDMy Profile

  8. says

    I feel like I’m getting there with perfecting my fuel game. Like you, I absolutely fueled too much in previous cycles. I remember the days of wearing a fuel belt full of sports drink + faithfully eating a GU every 45 minutes just like it says to on the package. GAH! While I haven’t been a “purist” with my glycogen depleted runs (i.e. I always have a bite to eat before I head out the door + coffee with cream), I definitely realize that less is more when it comes to eating/drinking on the go.
    Allison Johnson recently posted..Phoenix 3TV 10K Race ReportMy Profile

  9. says

    I wonder about this whole fueling issue a lot. I only ever have water during my runs which includes 20 milers, all those ‘sports’ drinks and fuels do not agree with me on the small number of occasions I’ve tried them. I am the type to question most things and i can’t help that feel there is a HUGE industry telling us that we NEED to take all this…stuff to make it through a marathon….I wonder. I am working hard towards marathon number 2 and have just gone from having nothing before I do my early long run to eating some oatmeal with a cup of tea or toast and tea. It gets me through 20 miles no problem, with just water (or no water if it’s cold) on the actual run, that includes pushing the last 10 miles at low 7 min/mile pace and even dipping into the 6’s.
    I like the idea of real food so much more during a marathon if I do have to have anything but I am so very tempted to run Houston with nothing but water. I also have a habit of learning things the hard way, I hope this is not another such occasion :s

  10. says

    I don’t like to eat during runs, but I’d struggle if I had to cut out all pre-run calories. Although lately, just due to my work schedule, I’ve found myself having to go on just a cup of coffee and a small bowl of oatmeal or a glass of almond milk, but I’ve gotten through just fine. So I do think there’s something to the idea that we don’t need to be chugging Gatorade and eating gels every 15 minutes. Honestly, when I read the packaging on certain race “fuel” products, I think their instructions are designed just to sell more product!
    Jen @ ConcreteNCoffee recently posted..Weekend/Sunday Funday(s)My Profile

  11. says

    This is great! I also do these depletion runs and they help my endurance a great lot. I believe in the coffee as well. It works! I have my long run nutrition nearly sorted out but still learn. As Catra Corbet said last week , she had to finish 86 hundred milers to finally get it right.
    Johann recently posted..Five Fotos For FridayMy Profile

  12. Jeff Irvin says

    Is that a coffee pot or is that your mug? if it is your mug I need to gets me one of those!

    Have you tried doing a hard effort the night before your long run yet? I did this a couple of times so that I’d be GD’ed but my legs would feel like shit too. Obviously, this isn’t something any of us would recommend doing on a regular basis or to a novice runner but DAMN, you really learn a lot about what you body needs or, more importantly, what it does not need.

  13. says

    This is so interesting to me. I really have to go back and read your earlier posts and research the whole GD thing more. Personally, up until now, my perfect pre long run food is oatmeal and a cup of coffee. It doesn’t cause me GI stress and it keeps my energy up. When I’ve tried a piece of toast with a little pb, I find myself getting tired midway. I also use gels. on runs of 8 or more. And coffee, always coffee before running, walking, or talking to another human.
    Jen recently posted..Taking control of my messy worldMy Profile

  14. says

    I’m definitely still working on it!! Something will seem to work for a while and then I’ll have a bad experience on a long run – HA. But I have learned that coffee before any run helps me…so I know make sure that I drink a cup of coffee first thing in the AM before I run.

    Getting so excited for you!!!

  15. says

    I pretty much do the same thing all the time. I eat bagel/butter or peanut butter, large coffee, sometimes a banana and go. Then depending on the distance, will use cliff blocks en route (usually just over 16 miles). In races it’s the same. I still have the large coffee too. Can’t run without my coffee :)
    Robin recently posted..Inaugural Downsview Half MarathonMy Profile

  16. says

    Since my little guy was born in May, I’ve become a 4 am runner and use both GD and coffee regularly. I’d agree that it really does help. Though I haven’t truly given full effort to marathon training with much more than a handful of GD runs during a build up, I am going to be during this one for my Spring race. I’ve done a couple of 16 milers GD already and most recently on Saturday, ran the last 10 min at just under MP, feeling the best I’ve felt yet. I do plan to extend them up to 18-20, but the key long runs where I practice a significant amount of time at race pace, and the last 3-4 weeks before the race will all be done with gels to both practice taking in food, as well as get my body used to it. I think it works well, and you sure do save a ton of $$$ not having to go through a handful of gels each time you head out. can’t wait to see how your race goes!
    LesserisMore recently posted..Running When The Sun Don’t ShineMy Profile

  17. Holly says

    It has been really interesting reading about the ups + downs of the GD training. People have posted great questions. I hope you continue to provide details. I think the biggest thing to me in reading about it is to ask myself why I am doing what I do. And when does it work/not work and why? Sometimes it is easy to take a gel when your running partner is – not when I actually need one.

  18. says

    This is such a timely post!! I’ve been experimenting with my fueling during training runs and just had a terrible race day experience so I’m going back to the drawing board. Thanks for sharing your experience.
    Holly recently posted..Track TuesdayMy Profile

  19. says

    I am not a coffee drinker at all in regular life, but I always have some before a race. If there is going to be a “literal outcome,” it helps it happen before the race, which I like, and like you said, it also helps with how I feel on the run itself.

    My fuel plan for the race is pretty solid–Shot Bloks and water when I feel like them, more at the beginning of the race. For me, it’s what I eat in the two days before that can hurt. I have to go really bland (like white bread and Special K bland) and eliminate dairy and high fiber entirely, or I will have problems.
    Terzah recently posted..A Virtual Race and a Long RunMy Profile

  20. says

    In college, our coach used to encourage us to have a half cup or cup of coffee before races (XC raced 5Ks). I was worried that the caffeine would dehydrate, but it never did and I always felt more alert and my legs felt more “on fire” (in a good way) an hour or two after a cup of joe. I’m all for it.
    Efo recently posted..FriendsGivings 2012My Profile

  21. says

    Just like you, I’ve learned less gets me more. I don’t do GD runs for my own nutritional beliefs but I do agree with you, we can get into a rut when we OVER fuel and it taxes our performance.
    As for coffee, I tried it one time before a run and felt sick the entire run. I couldn’t get the taste out of my mouth. I’ll stick to the caffeine in the gels.
    Joanne recently posted..CNYEats A Taste of Utica Calginiti aka Ceci CookiesMy Profile

  22. says

    That’s interesting about the coffee, I’ve always been scared to drink that before running too. I also did quite a few glycogen depleted runs this training cycle and was surprised by how good I actually felt. I’ll definitely keep it up.
    Beth @ Miles and Trials recently posted..Plan B…MaybeMy Profile

  23. says

    I had done a few glycogen depletion runs before my injury and they were better than I thought they would be!! I found running with just coffee actually was much better than running with any other fuel! I am glad to here you had success with them, as I plan to incorporate them into my training in 2013!
    Toni Church recently posted..Happy Hug A Runner Day!!!!!My Profile

  24. jason says

    Long runs with only coffee is wonderful. I’ve always done this because I run before work and there’s no way I’m getting up even earlier. I found out there’s plenty of calories from last night’s dinner to start burning fat stores. Make sure not to cave to last minute anxiety before the marathon by eating something. I did during last years NYC marathon simply because the wait was soooooo long, and i just gave into boredom and a nerves. Never felt so sluggish from the start.

  25. Ray says

    Drinking coffee before a run (advised time for other issues is 60-90 min prior) enhabces the burning of free fatty acids, which leaves the glycgyn for slightly later which pushes fat burning further back still. The whole thing is smoother than when digesting food.

    That being said I save coffee for race efforts, and never take food on training runs, and frequently no water either. I have done as much as 50K on nothing, several water only. Idid 50 miles once water only, and as part of a medical experiment once ran the better part of 14 hours taking only water and electrolytes, not a single calorie.

    Runners do tend to picnic too much in training, and especially races.

  26. says

    I totally agree with you on this post! I have to have my coffee before my runs/races…It just gives me that little pep in my step that I need. I have never been one to fuel on runs or race day so I am so glad that there is more info on GD. A lot of people would tell me I was crazy for not using gel or GU’s but I find that my body does not respond well to them and I will stick with what I have been doing.

    By the way Richmond was gorgeous and I think I will have to do that race again and add some hill training to my plan!
    stacey recently posted..Philadelphia Marathon Expo…We have a ChampionMy Profile

  27. says

    I usually have one cup of coffee and about a cup of oatmeal before my runs and then about 100 calories during any runs longer than 15 miles. If the run is less than 15 miles, I don’t fuel during at all. In fact, today I ran 13 and only had about 8 oz of water, which could be bad, but during my first marathon I drank so much water I had to stop and pee SIX times. I am getting a bit more productive with my runs/fuel!
    Travel Spot recently posted..10 Days of Thanksgiving: Days 9 & 10My Profile