While I'm sure a query of this nature has probably been responded to a dozen times before in this forum, I have yet to find what I'm searching for. That said, here's the situation:

I've been a runner since July of 2003 when I started LCing, but this summer I'm attempting my first marathon. I weight train 4 days a week, run 5 days a week, and do Pilates or power walk on my "off" days of running. Frankly, I'm an exercise nut, but am primarily addicted to running.

I run cross-country and do 5k, 10k road races, and have been training heavily for my first marathon (June 4). Amidst my low carb diet, I've found I don't "hit the wall" until after ten miles. At the ten mile mark my body completely drains of energy and I find I finish my run not because of my energy or Asics shoes, but because of sheer mental will--and the fact that I need to get home!

My real question pertains to how to modify a low carbohydrate diet for marathon running. Should I add complex carbohydrates to my diet so that I may run without "hitting the wall" or is there another way? Has anyone ever ran the most excruciating 26.2 miles of the human experience on a low carbohydrate diet and survived? Will it really matter if I do use gel packs like Carb-Boost (27grams per packet) while training, since it's being immediately processed by my body? Is diluted Gatorade okay to drink while training, or will this toss me out of ketosis?

I'm just brimming with questions. If anyone can help out, I'd surely appreciate it.

I don't know how many carbs you take in now, but I follow the Lutz plan (70 grams starchy carbs /day), and I find it fine for running/cycling for longer periods of time. Its NOT a ketogenic diet, since Lutz doesn't feel such a practice necessary, and recommends against it.

Hmm.

I should've read a few more articles before posting, since several other members are marathoners and have commented on the issue.

It's just frustrating, because the people in my marathon team are life-long runners and also happen to be cross-country coaches. They strongly oppose a low carbohydrate diet, and keep advising me that I'll bonk out with low mileage on race day if I don't "eat normally" the week before and morning of the race.

We train together four days per week, and they continually chastize me for eating LC. I know they're just concerned, but I'm not about to throw away two years of hard work and my current lifestyle. There has to be a safe way to do this and still maintain my current eating habits and training schedule.

I've been low-carbing (Lutz-style) for years, and I wouldn't go back to high-carb as I followed in the early 90's. I've already proven to myself that I can function better with low-carb. What's unsafe or unproven about it?? They're old school...

Since 1998 I used Atkins but don't agree with everything espoused by him. I favor a Zone diet approach: carbs always balanced with protein.

The basic reason for all these low carb diets is to control insulin secretion. Insulin seems to be the "malignant evil" these days.

Runners do not need to worry about their insulin. While exercising, blood sugar gets into the muscles by alternate pathways; no insulin is needed. This is why diabetics can run.

If you believe this premise, then what is needed is to carbo-load before a run and again after the run. The rest of the day, stick to the low-carb diet.

Saturday night I had three large slices of homemade bread with peanut butter for dinner. Sunday morning I had one cup of instant coffee then ran 23 miles. While running I sipped dilute gatorade. At the end of the run I had some more bread and peanut butter. During the run I never felt like I was hitting the wall.

The need for carbs is partially determined by how intense the workout will be. If you're doing 10 miles at a jogger's 12:00 pace, you aren't getting your heart rate up very much. You shouldn't need much carb. Maybe an apple before the run, another after. If you are doing 440 repeats, you are working your heart at 90% of max heart rate. For that you need all the carb you can choke down. Gu, Hammergel or boiled potatoes put carbs into the bloodstream the fastest.

The problem I have with the lowcarb diets is they don't know what to do with endurance athletes. They seem to favor the iron pumpers or truly obese. You need to find a middle ground. Low carb is healthy in most respects but you will fail as a runner if you don't treat carbs as necessary. I treat carbs as medication: needed for certain tasks, not needed any other time.

The lowcarb stuff makes your body more efficient at burning fat but whenever you get your heart rate above the fat-burning zone, you will fail if you don't have some carb ready. Lowcarb will burn the fat off, which is why many athletes do it, but they all recognize the need for carbs somewhere in their training.

This has always been an interesting topic, if not an outright dilemma. As a follower of Lutz, I take in a modest amount of carbs daily (70/80 grams starchy carbs/day), and have always wondered how low-carb affects the various energy pathways of the body.

If one looks at the energy pathways (three to six pathways, depending on sources) as defined by the usual diet, the body will use fuels based on the level/duration of activity, and not necessarily only one source of fuel. Follow the activity from short, limit attempts through increasingly longer anaerobic events to aerobic events, and one sees how the body uses up to six basic "mixes" of fuels.

So, does a body accustomed to a higher-fat diet learn to deal with fewer carbs during events where one would expect carbs to be the key fuel? Does low-carb change these basic fuel mixes? Does low-carb diets eventually provide a "carb-sparing" affect? Don't know, and I guess we all have our own experiences when testing low-carb against activities.

As I understand it, the fuel used depends on the severity of the exercise. At low intensity, such as walking or mild jogging, the body is using mainly fat for energy. At the other end of the spectrum such as 100 yard sprints or escaping a hungry lion, the body uses sugar. This makes sense from an evolutionary approach. The body can only store a limited amount of carb. But that carb has to be instantly available for avoiding the lion. I assume low carb diets train the body to be more efficient fat burners. I don't know if that is true but it is a logical assumption. But when you are out of glycogen, you are entering ketosis and cannot generate a fast sprint to escape the lion.

I read a study that was published in Runners World: Two runners with similar conditioning and body size each ran a marathon on a treadmill while hooked up to machines that recorded the calories burned and from what source, fat, protein or glucose. One runner did the marathon in 4 hours. 70% of his energy came from fat. The other runner did the marathon in 3 hours. 70% of his energy came from glycogen. Interestingly, they each burned the same amount of calories even though the 3-hour runner was working much harder.

I've come to see that my running suffers if I don't use carbs. I find I cannot run well if I am in ketosis. The difference is this: In ketosis I average 14 minutes per mile and it's hell. With carbs on board I average 8 minutes per mile and it's easy.

Note what you just wrote; that the two runners were using either 70% of one, or 70% of the other. What if the runners had been given time to acclimate to a low-carb diet? Would there have been any difference in the results?

Also, a 100 yeard dash is only about 10-11 seconds for world-class sprinters; this would appear to fall under the energy pathway that is basically ATP-PC, meaning no carbs at all are used, just ATP-PC.

Also, please note that I'm not speaking of ketosis; the Lutz plan is 70/80 grams of starchy carbs/day; he doesn't support ketogenic diets, at least not for the average person. And perhaps thats why I'm not convinced that low-carb diets are necessarily a bad thing for runners, cyclists. As a "Lutz" low-carber, I'm quite pleased with my running, cycling over the past years. But, again, I don't follow a ketogenic-style low-carb diet...

Interesting perspectives.

I'm not quite sure which road to take. I took Robert Frost's "road less traveled" yesterdy to see how my body manages in ketosis during longer runs. Right now I'm comfortable at a 9:00 minute per mile pace when running short distances of 5-6 miles. I don't feel fatigued or sluggish when eating 20-30 grams of carbs per day. Most of my carb intake is in the morning for breakfast prior to work. I stick mainly to lean proteins and salads for lunches, and have an Atkins-like protein bar after work prior to lifting weights and running with my veteran marathoners. During our training circuit, I seem to function just fine.

However, as soon as I upped my mileage on this same diet over the weekend, my body quit on me somewhere around mile 9 at a 9:30 pace. I don't know if this was because I was doing a very intense hill workout, or because I slammed into the infamous "wall" due to lack of glucose.

After talking with a trusted trainer at my gym and a licensed nurse practioner, they both recommend that I start "cycling" my carbs, i.e., little to no carbs on light running days (3-5 miles), and 40-50 grams on more intense days (6-8). I think I'm going to try your advice, Kaypeeoh, and eat whole grain bread with peanut butter or fruit before longer workouts.

It's amazing, you know. My family is heavily immersed in the medical profession, and after plaguing them with questions about the diet they have no valid answers for me. While some of their colleagues advise the low carb approach, most only recommend it to diabetics or the severely obese. When I started all of this two years ago, I was definitely about 40 pounds overweight. Not the dreaded "obese" but definitely unhealthy. Now that I'm "fitter" than most of the American population, no one seems to have any answers, and all of the research is fairly new.

I just wish I would've thought seriously about nutrition before I decided to undertake a feat such as the marathon. Now I've screwed myself into training and experimenting at the same time, when all I really want to do is get out there and run.

Kaypeeoh, I aspire to your comfortable 8 minute pace for 23 miles. Here, bask in my glow of admiration.


"Marathoning is like cutting yourself unexpectedly. You dip into the pain so gradually that the damage is done before you are aware of it. Unfortunately, when awareness comes, it is excruciating." ~John Farringington

I think your trainer is starting to 'get it'. I don't have the answers either. I know I feel better on low carb. I don't get indigestion or heartburn. I don't get canker sores. All of which I lived with for much of my life. I'm less heavy which makes the running easier.

For now my training revolves around having carbs on board for serious runs. Like you, I don't seem to need much for the shorter stuff. I think you bonked when you ran out of stored glycogen. It happens sooner if climbing hills. Anytime your heart rate is high, you're burning sugar primarily.

April 23rd I'm running a 50 mile race in Fruita, Colorado. My plan is to eat as much protein and carb as I can the week prior. During the race I'll use Hammergel. I may change my plan tomorrow. Who knows what is best?

I've been wondering about this for quite some time as well. I've noticed that as I stay on LC for longer, my body is adapting better to exercise. But I don't do endurance events at present either, just short HIT stuff.

Now, I came across this site today, and you all should read it. In fact after reading it, I would say "carb loading is a load of sh*t", would be the summary.

If you're "bonking", try eating more FOOD, not more carbs! We're all so brainwashed...why not try a chicken leg or leftover steak on your next long run/bike, instead of some sugar gel, and let us know how that went...

remember, historically, humans did occasionally have to do some long-distance "exercise", and yet we somehow managed to survive without hammer gel or watered-down gatorade...

When I started LC I thought I needed "carbs" during exercise too, I used to use honey...all it gave me was hypoglycemia. It did not improve performance at all. But again I didn't do long distance stuff.

So... read this page it's VERY enlightening!

DIET FOR ATHLETIC PERFORMANCE:
http://www.second-opinions.co.uk/athletic_diet.html

The human animal can only store one day's worth of glycogen. That's enough for a 20 mile run. Once you run out, you're relying on fatty acids for energy. It's logical that nature only allows a small amount of glycogen storage. Early man was a hunter-gatherer. That meant working constantly but at low heart rates. Occansionally he would have to race to catch an antelope or avoid a lion. Then he was working at 90% of maximum heart rate, which can only be done using glucose.

I've used Atkins since 2003. I'm a distance runner: 30+ marathons, 15 fifty-mile races and so far, 5 one-hundred-mile races. I'm always one of the last finishers. I attribute that to not having a storage pool of glycogen. On the plus side, by relying on fatty acids for energy I don't suffer a lot of lactic acid induced muscle soreness post-race. In races, I eat a mix of fat, protein and carbs. I've tried running long distances with no carbs on board and invariably fail. Meaning that I'm reduced to walking in the later hours.

I lost 165 lbs so far on Atkins and Running Phase I. In the past 6 months I do atkins phase one on lower output days and up to 40-50 net carb on longer run/training days. Just Did My First 1/2 Marathon Official Race w/ 11.5mins/mile in Chicago Lakeshore Marathon on Memorial Day 2005. I did a half marathon on my own in training 3 weeks ago also with only 30 net carbs of food, and I drank one 16 oz diluted bottle of gatorade in 20 minute intervals before during and after the first half. I felt so sore after. Later instead On Memorial day I ate italian the night before with noodles and seafood and had a bagel w/ LC PBJ for breakfast on race day. So this time I consummed 24 oz's Accelerade before and during the race with one banana and one scoop of endurox 2 hours post race. I felt so good this time having upped the carbs like medicine to enhance my performance. I feel so good 48 hours post race that I signed up for the Chicago Marathon today also. I am just about to up my distances while training for the Lake Zurich Triathlon On Aug 14. I need to find the lutz meal plan for endurance athletes so I don't have to reinvent the wheel. Let me know if you have a training plan for me to follow to train for both Lake Zurich Olympic Triathlon and Chicago Marathon concurrently along with a complimentary meal plan to go with the training plan.

Joesterdamus
my email is the same handle on the microsoft network emai system.

The Lutz low-carb plan outlined in his books is basically the 6 bread units (about 72 grams of starchy carbs) per day, so its not specifically a "ketogenic" diet. Its also based on the Austrian treatment system for diabetics used prior to WWII.

He doesn't support very low-carb plans, and does suggest sticking with animal fats over vegetable fats. Life Without Bread is the only one of his books currently available in english.

It sounds like you're getting the idea. I think the official Atkins website has a physician/triathlete who went from back-of-the-pack to front-of-the-pack when he switched to Atkins. If he's still posting there, you might get some dietary advice from him.

Right now my breakfast is oatmeal, soymilk, eggbeaters and peanut butter, all microwaved together. Lunch is turkey and cheese rolled up in a burrito. Dinner is stir-fry fish and veggies. For snacks I eat almonds throughout the day.

For Sunday long runs I'll have oatmeal mixture for breakfast and nibble on pringles while running. I'll go through nearly two of the sleeves during the run. I drink gatorade for extra salt.

Last month I had planned a 50 mile trail race in Colorado but I turned an ankle around mile 9. I had to hobble the next 16 miles before I could get help. The diagnosis was a torn talofibular ligament. I'm back to running 50 miles a week but every mile, every step, hurts like hell.