If you are on a low carb diet that feeling you are getting that you describe as "not having your legs underneath you" is because your energy stores (glycogen stores) are extremely low. Those energy stores are essentially CARBS that your body has stored. BCAA are essentially more protein and research is very limited and conflicting if they in fact aide endurance. Protein is a very bad energy source. There is nothing wrong with eating bread and pastas as long as you eat them the right way. Whole wheat bread and pasta's are great.

If you want to be serious about endurance training, you cannot get by on a low-carb lifestyle. Carbs are your energy source.

I think you've trained yourself to view all carbs as bad, which they're not especially for an athlete. The whole wheat, natural carbs you allow yourself to "cheat" with on weekends are precisely the type of carbs an athlete's body needs, in a relative abundance

[quote=outexan]Protein is a very bad energy source.[/quote]

can you elaborate? that sounds oversimplified to me...

It sounds to me like the fitday.com thing would help you. There you can keep track of everything you eat every day. Then it will show you your balance of fat/protein/carbs.
I was carb-phobic as well. Yet as they are saying, if you are training hard, protein isn't going to do it for you. With fitday I now eat 15% fat/ 20%/ Protein/ 65% carb.
As for keeping your eating habits... chances are you will make some adjustments. I'm guessing you will be glad for the changes once they are your new "habit".

Fitday takes discipline, especially for the first couple weeks learning how to use it and entering custom foods. I found after 2 weeks it was very quick and easy.

+1 to outexan.

Also, I would be cautious about the 'long-term health benefits' of the low-carb things. Cutting out a huge category of food choices makes it easy to lose weight because there's a lot that you simply don't eat anymore. But that also cuts out a lot of potential nutrition, and not just carbs. You might try applying your dedication to making food choices based on glycemic index, which adds some nuance to the whole thing.

Since you are asking a lot of your body, you should give it what it needs. It might actually be worth talking to a nutritionist with a degree in this sort of thing to be sure you're on the right track. --M

From what I understand about protein, it is more utilized in rebuilding muscles or recovery. You burn fat at low intensity and carbs at high intensity and those are your "fuels" while working out. Protein is too inefficient to fuel a workout. In other words, protein is good to have in your diet, but not to fuel your workouts. I'm no expert, I just read a lot of books

There's a saying: "Fat burns in the fire of carbohydrates." You can't lose the fat if you don't have any carbs in your belly. Throw training into that mix and I think you're going to have recovery issues. My suggestion: A balanced diet, exercise, and time. Just think of it as putting skinny on layaway.

You're fine cutting out the bad carbs as you stated- breads, pasta, white rice etc. and still being able to get good carbs to fuel/recover from workouts and still lose weight. Focus your carb intake around fruits and vegetables. Eat bananas, sweet potatoes, dates, mangoes, grapes, cantaloup before or after workouts and take in apples, pears, berries, beans, lentils, green veggies, grapefruit, oranges, etc. with meals.

First of all, let's not call them "good" and "bad" carbs.

Second, I think that the sentiment from all the responses pretty much sums up what I would say. I think that it's best to just eat a balanced diet.... As for me, I try to avoid refined sugars, but don't really pay much attention to carb-intake all that closely. If I eat pasta, I try to make it whole wheat. If it's not, well I try to make sure I counter that with another vegetable that is high in fiber... I find that I feel much more "in balance" when I accompany any type of grain with a salad. Whenever I have my pre-race meal, I have a big salad along with it. I'm not sure if it's real, or just a placebo effect, but it helps me control the pre-race jitters.

But I'm getting off track... I would also like to add that your body doesn't work like a warehouse. You can't eat carbs all weekend, then expect them to last for the whole week. Carbs are your body's first source of energy, so if you take them in, your body is going to use those first... so the whole idea of "cheating" to let yourself have those carbs is a bit off-base. Don't get me wrong, I love cheat days as much as anybody, I'm just saying, don't base your diet around a cheat day, especially since your body has no way of stretching out that intake over a whole week.

[quote=jsk85]From what I understand about protein, it is more utilized in rebuilding muscles or recovery. You burn fat at low intensity and carbs at high intensity and those are your "fuels" while working out. Protein is too inefficient to fuel a workout. In other words, protein is good to have in your diet, but not to fuel your workouts. I'm no expert, I just read a lot of books[/quote]

jsk85, you hit it on the head. Your body wants to use carbs first, fat second and protein very last for energy. Our body knows nothing about training or carb loading or any of this. All it cares about is surviving. Therefore your body will resist using protein as an energy source until all of the fat and carbs are used up.

You can't think of carbs as "good" and "bad". Food is not "good" or "bad". There is an appropriate time and amount for everything. Low carbs is not the way to go for tri training - you are probably feeling low energy while training because of depleted glycogen stores. I suggest reading "Sports Nutrition for Endurance Athletes" by Monique Ryan.

I took a class in nutrition and I've read a couple of books on it. You can be as meticulous as your want, but all the research just comes down to moderation in the end. Moderation with more foods that are natural than foods that are highly processed. Timing also becomes more important when your are an athlete. The time when it is really important to eat simple sugars is during and right after a long training session. The time not to eat simple sugars would be right before you go to bed. BCAA's are just protein - you are probably already getting more than enough of that.