Low carb and racing

I've tried low carb before (that is, between 70-100 grams carbs a day on most days, even dipping down to less than 70 grams carbs on some days). I was also training for a marathon. The results were not good for me. I was unhappy and was feeling sluggish and had no energy. I also had difficulty controlling my BGs.

Now, there's this book titled The Art and Science of Low Carbohydrate Performance (Volek and Phinney). Since the book specifically targets athletes, I thought it may be a good idea to give their plan a try and low carb another chance. From what I can work out, they are generally advocating less than 50 grams carbs a day (that would be really low, for me). They also go for high fat and low protein. Sorry, I can't remember the macronutrient ratios at the moment.

Is there any one who is eating less than 50 grams carbs a day and racing? By racing, I mean competing in athletic events, whether as a pro or an amateur. Athletic events can be running, swimming, cycling, triathlons, race walking, tennis, and so on.

If yes, would you mind sharing your experiences, such as:

(1) difficulties when initially adjusting to the less-than-50 grams carbs a day
(2) how long your adjustment was (the authors say 2 weeks)
(3) any adjustment to your training program as a result of changing your diet
(4) any problem you have encountered which may be related to the diet and how you deal or dealt with it
(5) effect on your racing time

Given my previous unsatisfactory experience with low carb while doing marathons, this time, I'd like to arm myself with as much info as I can gather. I'm looking for ways to improve myself and am willing to try new things provided I see some logical reason to try them.

Thanks in advance.

I used to maintain a very strict less than 50 carb diet and was training and competed in a marathon - the transition was tricky in that off the bat you can't sprint very well and you BS may drop often-

however if you transition during a "non-training" season I find it works out better (such as go 2 weeks with only walking or light wt lifting then after you have been on the diet that long get back to normal workouts)

once race day came I hit my pace band perfect (well four seconds off but thats not bad for runing 26.2 miles) I never hit "the wall" and for the first half of my race only drank water and ate high fat/ low protein/ no carb mix - then after mile 14 because of the heat I gave into an every 4 mile chug of Gator-aid and mile 20 and 23 hit one gu pack- looking back now if i had been no carb longer i would not have resorted to the gator-aid or gu as this made me go high by the end of the race. on training runs i would hit 20 miles with just water/ cream chz/ and a few slices of summer sausage*** and no pump*** - by the end of those 20 miles my BS was the same as when i left

now i only run 5-6 miles a couple times a week and have more carbs , but because of this I have put on about 10 pounds-- i am trying to get back to less than 50 carbs a day - i feel better and maintain a better wt.

Hi there. I run, swim and weight lift. I'm T1 and on Tandem T:slim insulin pump. I can't even imagine 50g of carbs a day; I range about 150 and have very low body fat. I found this youtube about meal-planning and found it super informative. It's not necessarily for low-carb or diabetes per se, but it really shed the light on caloric intake and the difference of how much energy you get from protein vs. fat vs. carbs. .. Check it out!

i've also been told that even though you're eating low carbs, the protein you eat will convert to carbs in order to produce energy in the body. this is an "unknown" carb count; so you may not be bolusing for the additional carbs the protein converts to. don't know a whole lot about this, but heard it recently on a Webcast from Gary Scheiner.

Thanks for the responses so far. I'll be training for a November half-marathon and then a March marathon. I am still considering whether this is worth it. I'm always looking for ways to make my athletic life a bit better (I am not the fastest runner out there). I'll be watching the video that MichaelA recommended.