Glycogen Part 2

Monday, September 10, 2012 · Mike Davis

The first part of this two part blog discussed the effects of glycogen on you and the benefits both in weight loss and your daily energy. Using the glycemic index you can make choices that avoid sugars that eventually equate to increased pounds as well as zapping your prolong energy level. Having a cup of coffee will provide increased energy and performance, adding sugar will increase weight and may counter the energy benefits. Interesting….

How will the glycemic index benefit your running? Let me share an experience with you. A few years back I ran my first marathon in Frankfurt Germany. I was pretty ignorant of the dos and don’ts of running a distance of that magnitude. I was going along and around mile 16 I begin to struggle mentally and physically. A water stop came up and I was surprised to see a table with small cups of coke there. Having quit soda some time ago I surprised myself by grabbing one of the small Dixie cups of soda. I emptied it into my mouth and enjoyed the bubbly feeling as it went down. Within minutes I had a great feeling come over me like I was suddenly refreshed! OMG, I found the secret to success in marathon running. That feeling lasted maybe 5 minutes (if that) and as I came down from the sugar spike I felt worse than I did before the coke. I struggled on hoping to come across another coke station as I was in dire need of another shot! I believe I hit 2 more stations that provided coke but each time it got worse for me. Mentally I blocked out what I was doing because I wanted to somehow get enough spikes to get to the finish line, but in reality I was suffering because of it. Coke= High Glycemic

That marathon was my first and I really never discussed nutrition with anyone, so I just did the carb loading that Runners World directed. That strategy didn’t really help me personally even beyond the soda decision (which was not a Runners World suggestion), as I became somewhat glycogen starved. Understanding what fuels our bodies while we exercise is not as simple as some publications or other resources might indicate. The carb loading strategy seems to be somewhat universal and I would dare say it’s popular because folks enjoy guilt free pasta loading. However, a balanced approach using both the lower end of the glycemic index while choosing your carbohydrates gives you better stored fuel.

As we run outside of 60 minutes muscular and liver glycogen deplete and that’s when we begin to struggle both physically and mentally. So a simple thought is that we should eat the right carbohydrates that increase our glycogen levels and then we can run for hours without a problem. Nice idea, not totally wrong, but not necessarily scientifically proven. Improving our glycogen levels certainly appears to help us, but there are no studies that provide us with a formula that will insure we have enough fuel to sustain us for extended periods of running. Does that mean that we should not attempt to store additional glycogen prior to or even during a long run? No; there’s enough data to show that glycogen levels are linked to our bodies fuel and proper increases will help to sustain distance running. Confusing yes, but while increasing our glycogen level is helpful, how much your body can store both physically and safely is debatable. At some point an increased amount of glycogen becomes useless as your body will only store so much and then you run the risk of GI issues or a bellyache. Don’t believe there’s a formula, as of yet no studies have proven there is one.

Bottom line

Pay attention to your consumption, focus on low glycemic products that will increase your glycogen (stored fuel), but don’t overdo it. A few days out from a particular long run (70 minutes or longer), eat some good carbs (low glycemic) and decrease as you get closer to the actual run. Don’t stop fueling, but don’t go heavy. During the run you might carry something that your digestive system has told you it can handle and provides some increased glycogen. There’s no perfect formula but you can use your training to figure out a balance that works for you.