Glycogen Depletion Training

I read an article on glycogen depletion training and decided to give it a shot for my 15 mile run yesterday. What is glycogen depletion you ask?  It's when you go for a longer run that will last 1.5-2 hours and you don't fuel before or during your run.  It's suppose to train your body to use more fat for fuel. Apparently ,if your body isn't used to using some of your fat for fuel, you will end up hitting the wall or how they call it, "bonk" after about mile 20 during marathons.  They say to do this 2-3 times per training plan when you hit 14-18 miles.  The goal for this type of training is to work on endurance training and not speed work.  I have never been a big breakfast eater so knew it wouldn't be hard for me.  In fact, I usually train and do my runs first thing in the morning and I always run on an empty stomach.  I just take my water to hydrate as needed on my runs (I don't drink a lot because it makes my side hurt or makes me want to stop for bathroom). Everybody is different and that's what works for me.  However, if I do run more than 13 miles, I eat half a banana before heading out the door and take my favorite Gu to eat half way through my run.  So, I took with me a whole banana and 16oz water with Amino Energy to hydrate and eat after.  I usually drink coconut water, but didn't realize I was out.  It's still very hot in the mornings here in Texas and started running at 80 degrees.  Last weekend I ran fast in the beginning and then bonked at my last 4 miles because it got hotter, I was running against the sun and just ran out of fuel!  So, I decided to do the opposite and shoot for a negative split this time and not worry about my pace just endurance.   I have to admit, I have never bonked during a marathon.  Most of my problem after mile 20 is usually injury related like cramping, but my endurance is still good.  Training in this hot summer is what is tough for me.  Friday night, Eddie and I went to eat and got my carb load by eating some lasagna and a lot of water with lemon.  For my 15 mile run Saturday morning I didn't eat anything other than drinking my water and ate 3 gu chomps before my run and then 3 more half way through (a little fuel). Well, guess what??  I did way better than last weekend and wasn't hungry nor did I miss not eating that half banana like I usually do.  My pace improved by 5 minutes and I ran one mile more than last weekend!!  Yes, it's true and I started off way slower than usual, but was able to speed it up my second half.  I ran off that lasagna and used my fat for fuel.  Of course, after I finished I drank all my drink and ate that banana in a heartbeat!  The best part was that I didn't feel exhausted the rest of the day.  So, I plan to do it again!