So I mentioned in my last post that I was trying a new fueling strategy. Partially prompted by my review of why I bonked during my long run two weeks ago and partially because I am always on the look out for new research etc on topics like this.
The change was prompted by a posting on the 1stEndurance blog reviewing Carbohydrates for Endurance Athletes. While I am no foodie (or control freak) per se I do believe in taking control of the things you can and fueling and hydration is something that you can definitely take control of. I should also caveat this by saying that I am no qualified expert, this is simply based on my own experience and I apologize if this gets too technical but I will try to dissect the info into bite size chunks for your consumption.
Glycogen is the body’s store of carbohydrate based energy; the body has a glycogen store of 1500-2020 kcal. Therefore the body typically has enough of this type of energy store to fuel 3 hours of exercise, assuming a consumption level or 600-700 kcal/hour. Any marathon runner, in fact any runner, has probably heard mention of the wall, this is the threshold the runners encounter typically around the 20 mile mark or three hours, working on the standard of 100 calories per mile, (personally I consume a little higher: 130), assuming that there is no replenishment along the way.
When you exercise or race at or above your threshold level blood is drawn away from non essential functions; digestion is one of these functions, and redirected to the working muscles, this leaves the digestion of foods difficult and can lead to gastric distress and dehydration. This is not something I personally suffer from, but I know a lot of people do.
The criticality comes in consuming the right carbohydrate at the right time as not all carbs are created equal. You may have all heard of slow burning carbs like oatmeal and faster burning carbs like, say, a doughnut. You don’t have to be the sharpest tool in the shed to see the difference between oatmeal and a doughnut, well how about oatmeal vs. a bagel?
Well this is where my change applies; my typical pre-run staple has been a bagel…oops!
Before I commence on the great bagel debate I want to bring into the conversation another measure called the Glycemic Index, the Glycemic Index measures how fast a food is likely to raise your blood sugar. The Index is generated based on glucose, which is one of the fastest carbs available. Glucose is given an arbitrary value of 100 and other carbs are given a number relative to glucose.
This is helpful to know because if your blood sugar is low and continues to drop during exercise you would eat a carb that is high on the Glycemic Index i.e. water melon (Index # 72) this will raise your blood sugar quickly. On the other hand for endurance athletes to keep the blood sugar from dropping during hours of activity, you would eat a carb that has a lower glycemic index and longer action time i.e. fettuccine (#32), hence the pre-marathon pasta dinners you see.
So the proposition is that before exercise you need to ingest slow burning carbohydrates or carbs that are LOW on the Glycemic Index, these, consumed 30-60 minutes before a race are beneficial in as much that they prolong your endurance level.
During exercise there should be a focus on a mix of HIGH and LOW Indexed carbs that both top up the tank immediately and also add fuel for the longer term. Consuming carbs; specifically those that contain fructose (#20) and or glucose (#99) that are easily digested and absorbed reduces the potential for stomach issues and address the immediate and longer term needs.
Post race consuming foods HIGH on the Index promote a speedier replenishment of the lost glycogen stores; additionally protein ingestion has been noted to improve recovery.
So how does the lowly bagel come into play here, well put simply the bagel has an index number of 72! So my simple strategy was to swap out the bagel for a bowl of my cereal killer, and to be quite honest the impact was quite amazing. A 1000g bowl provided 585 calories, during the ride I consumed a bottle of EFS Liquid Shot (400 calories) a bag of Sharkies (140) and a Cliff Builders Bar (270), fluid wise a bottle Amino Vital (90) and two bottles of Perpetuem (520) total 2005 calories, sounds a lot right, well according to my Forerunner I burnt 4050, even allowing for a +/- discrepancy of 20% I was well into the red, however finishing the ride I still felt strong and fueled up with more miles in the tank.
So in typical verbose fashion the take away (excuse the pun) here is; bagels are good after the run and so bye bagel bagel bye bye…at least till I get home, when in fact it would be a good thing to eat!