Saturday, June 16, 2012


ram·bling  adj.
1. Often or habitually roaming; wandering.
2. Extended over an irregular area; sprawling: a large rambling country estate.
3. Lengthy and digressive: a rambling speech.

rambling  adj
1. straggling or sprawling haphazardly; unplanned a rambling old house
2. (of speech or writing) lacking a coherent plan; diffuse and disconnected
3. (Life Sciences & Allied Applications / Botany) (of a plant, esp a rose) profusely climbing and straggling
4. nomadic; wandering

I enjoy the running I do with Team in Training because I get reminded about just how many questions new marathoners have.  In the past we have discussed shoes, hydrations packs, stomach cramps, and other common concerns.  

Today as we physically rambled along the trails and paths of a beautiful NJ park, I got to verbally ramble with the group about fueling and bonking and what to do to avoid this. I enjoy this topic because in order to understand how attempt to avoid bonking, we have to discuss a whole lot of related topics, like hydration, electrolytes, and fuel consumption.  

My position on most things related to running is to quote Sheehan and explain that we are all an experiment of one.  I also like to use myself as an example of someone who has done absurd things which turned out to bring me some success.  For example, I fueled my best marathon with 6 gels.  This seems excessive to most people.  I took 1 before the start.  I opened 1 at the gun and sipped it through mile 4.  By mile 5 I opened my third, by mile 10 I opened my 4th, by mile 15 I opened by 5th, and by mile 20 I opened the last one I could tolerate.  I drank water and gatorade at each water stop.  I took a few e-caps at the start and half way.  I ran a 3:15 and took 3rd place in the race.  

This admission of gel gluttony often gets some reaction.  This leads me into my next question which is how well do we understand how many calories we burn per mile and how much fuel we need to succeed.  Most new runners have no idea how many calories are in one gel let along how many calories we burn per mile. 

In general, most runners think a good rule of thumb is to guess 100 calories per mile.  So that suggest that without counting a few ounces of gatorade or anything (usually liquids) that I consume pre-race, I am burning 2600 calories during a marathon, while consuming 600 calories in gel.  It no longer seems so absurd to consume so many gels for a marathon.  It even seems like maybe I should be taking more. 

This leads us to discuss how much energy the body stores.  We know that carbohydrates are the primary energy source for muscles.  Specifically, glucose, the product from breaking down carbohydrates is the fuel we use.  Glucose get stored in the body as Glycogen.  Apparently we store glycogen in our liver (100 g) and in our muscles (500 g).  The 500 g in our muscles will provide us with close to 2000 calories worth of energy.  If you don't fuel up properly or allow your body to be depleted, you may have less.

Ok, so  this suggests that the 2000 calories of energy stored in my body plus the 600 calories I consume during the race is enough to get me through the marathon.  It seemed to work for me that day. 

However, I recently learned that the 100 calories per mile rule is not so accurate. Apparently this information has been floating around for years, but I did not know it.  According to the cited article the most accurate formula for determining your "net calorie burn" (calories burned minus basal metabolism) is to multiple your weight in pounds by .63.  So a 120 lb woman burns about 75 calories per mile.  This information is not terribly crucial.  It could help with making sure your recovery meals are not more than your net burn if you are attempting to lean up.,7120,s6-242-304-311-8402-0,00.html

After spending all this time pointing out how I consumed a bunch of calories and ran a bonk free marathon, I then like to share the story of my PR 50k from 2011.  During that race, I consume some real food prior to the event and only fueled en-route with 2 gels and about 20 oz of gatorade.  I ran a 4:15 31.06 mile race with a 5 second negative split with my last 5k faster than my first. 

How can it be that a ton of gel was just as good as two.  My only explanation is that the body burns energy in mysterious ways.  Weather may be a factor to help us stay hydrated and tolerate fuel. Also I am a fan of occasional depletion training.  I tend to trained depleted when I run with TNT.  I believe that as we training more, we use less fuel because we get more efficient, but what do I know?

I share my 50k low fuel story after seeming to suggest that tons of gel is the way to go to show that there are many ways to fuel a race. I believe that good training helps us run more efficiently so less fuel will be needed.  I believe that good pacing can help avoid a crash at the end.  But most importantly I believe that we have to just experiment with what works for us and it may vary as we get fitter.  Newer runners, who may run slower and less efficiently may need to fuel differently than leaner, lighter, faster, more efficient runners.  

I have found success and failure with both consuming a lot and consuming a little.  I am sure there are elements that can't be identified that do influence what each runners needs.  So I encouraged those I was with to alternate their fueling.  Some runs train by consuming more fuel.  Other runs, train by consuming less and just see how it feels.  

I have no idea what is the absolute right way to fuel a marathon, but what I do know is that we need carbohydrates, electrolytes and water.  Give the body those things in moderation and it should make the experience of running a marathon much better than if you fail to supply one of these vital elements. 

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