Confused about carb loading?

[UGAFan0829]

I've read and heard lots of things about carb loading before a race and I'm a little confused since it seems to have a different effect on me. I understand that the carbs help give you the energy you need to go long distances, but when I eat carbs I tend to get a lot more winded. For instance, before I ran my first half, I had pasta and bread for dinner. I struggled nearly the entire race with feeling like I was having a hard time breathing. Then before the last half that I ran, I had chicken fingers for dinner and didn't hardly feel winded at all. I've noticed the same thing happening with my training runs. Does anyone else experience this, or am I totally missing something?

 

[SAHDad]

Well, first off, every runner is an experiment of one, ultimately. What works for others might not work for you, and vice versa. If you feel sluggish or winded after having pasta the ngiht before, but fine with more protein, then go for the protein, and ignore everyone else.

I've never noticed a huge reserve of energy after carb-loading, nor a lack thereof if I fail to do it, but I have learned to avoid unfamiliar foods the night before a race (or a long run).

Just a random fact - originally, the carb loading was part II of the process - you ate almost nothing but protein for most of the week before the race, and then nothing but carbs the day or so before. The first part got dropped, and the pasta dinner has just become a marathoning tradition.

 

[rubato]

I try not to eat a big meal of anything the night before. I eat a decent lunch, but then have something light for dinner. I don't want any "issues" the morning of. I eat a very balanced diet, try to do a little protein loading the week before and a little more carbs the 2 to 3 days prior to the race. It is a very personal thing. Each person's body needs something different.

 

[ChimneysweepGeorge]

A few things to bear in mind about carb loading.
First is, effectiveness is highly dependent on how you train and what your normal diet is. The whole point of the exercise is to make sure your glycogen stores are full. On a proper taper, with a proper diet for an endurance athlete, it's not a huge difference.

The second thing is the race distance. At any distance under a half marathon, it's largely irrelevant, you aren't going to deplete anything and honestly, even most people will still be fine for a half.

The whole point of full glycogen reserves is to reduce the chance of a "bonk" where you simply run out of easily available energy and the remainder of the race becomes murderously hard (called "hitting the wall"). Slow or heavier runners can have this happen inside a half marathon but for most people, this starts to happen somewhere around mile 20. That's why the joke about a marathon being a 20 mile warm up for the most miserable 10k of your life is hysterically funny to people who have run them.

 

[cewait]

First a little background on carb loading; what ideally is and what it has become and how it can be abused.

Carb loading is a method of topping off sugar (glycogen) stores in the body. Carb loading actually starts with unloading. A true carb loading activity requires a few days of carb depletion in the diet coupled with higher intensity workouts so that in layman’s terms, blow the soot out of the system. Your workouts should be star seeing I feel nauseous type of big muscle work. It should occur over a 2-3 day period 7-10 days pre-race. From there, while maintaining you Kcal you up your carb intake by 10-15% for 3-4 days. I have gone through this cycle and the first time I went through, I was ready to shoot my coach as I felt sore and weak for a couple days. Then all of a sudden my body felt refreshed and I ran a couple PR’s This is not a pleasant experience and not one that I recommend to anyone who is just looking to finish.

What it has become… simply a pre-race party where we get to have a meal with fellow runners. It has morphed to a night before the race meal, way too late to do anything physiologically other than top off you sugar stores. It really serves no other purpose than to celebrate, “I have arrived and I am ready to slay the course.”

How it is abused… First, the average person in the US population carb loads as a matter of course with their normal diet. Many American’s diets are 60+% carbs or higher. If you think comfort food, or processed foods, you are really thinking carbs. I have seen folks go back for 3rds and 4ths at a prerace pasta feed. I have always wondered if they were the runner or the spectator… I am never sure how they would digest their intake over the next 5-7 hours.

A good rule of thumb is to follow a balanced diet plan as you train. Feel free to bump carbs up the night before a long run, but within reason… but make sure that you stay light with the meal. If you feel satiated or stuffed, then you over loaded. I think it more important as you come into a long run (training or race) to hydrate very well (to a point where urine is just colored) and keep you meal the night before light. It is also important to eat a carby breakfast 2 hours or so prerace so you spike up the glycogen levels in the blood stream as the race starts.

What I have been reading about over the last 3-4 years is fat loading the 2-3 days prerace and how it can work to fuel your engine. Note that your body looks to two fuels (there are others but keeping this simple) for running down the road. Sugar or carbs is a high energy, fast burning fuel. But if used exclusively, you will fall flat on your face in less than 90 minutes. The other fuel source is from fats. Your long lean slow twitch muscles (the ones you recruit for a marathon) use fat as their fuel source. Your body has multiple days of fat stored and ready for use in the event it needs a long-term fuel. Walking is almost all fat sourced activity while sprinting 100m is an almost all sugar-based event. Running a marathon is a uses a high percentage of fat as fuel, but requires some level of sugar for the fast twitch muscles being recruited for speed. All this to say that fat loading has some merit, if done correctly. Again, we are talking about shifting the diet 10% higher in fat for 2-3 days. Remember it should be good fats and not the bad ones. Even with this type of loading, I shift back to a light and balanced evening meal prerace.

A lot of stuff to say hang in there. It takes some experimenting to see what your body favors. Based the fat loading theory, your chicken fingers are not all that bad.

 

[ChimneysweepGeorge]

What I have been reading about over the last 3-4 years is fat loading the 2-3 days prerace and how it can work to fuel your engine.

The problems with that are largely the same as carb loading for the average American. A pound of fat will power an average person for 4-6 miles. So unless you have a VERY low fat percentage, you are in good shape.

It's also worth noting that sugar and fat as fuels is even slightly more complex and that's worth talking about. Too many people are under the impression (fostered by companies selling HRM gear) that there is somehow a switch between the two fuel sources when there isn't. It's always a continuum of what fuel you are burning the most of at a given moment. This is an important distinction because you are always burning glucose. The processes that turn the various fuels in your body into ATP are all dependent on the presence of glucose...in other words, once your blood glucose and glycogen stores are depleted, it will take your body a long time to create more ATP. Your central governor knows that this is bad news for your body and will attempt to slow or shut down voluntary muscle activity, depending on how dire the situation has become.

 

[rubato]

From what I understand, our body uses stored ATP, then stored creatine, then stored glycogen and turns each of these into ADP. Then, we turn to fat stores and lastly to muscle protein. I agree with Coach that our american diets are already so full of carbs, that carb loading doesn't tend to work. I think a bigger thing to consider is our stored oxygen levels. More training would be a more efficient way to race. If we can go longer in an aerobic state, we'll burn that fuel more efficiently and have less lactic acid buildup. This might be why you felt so winded. I not only don't carb load, but I try to eat almost no processed foods. I do add a tiny bit the few days before the race and at lunch the day before the race, but that's it. Then, on race day, I like my simple sugars. I think if you experiment while you train, you'll find what works for you.

 

[ChimneysweepGeorge]

From what I understand, our body uses stored ATP, then stored creatine, then stored glycogen and turns each of these into ADP. Then, we turn to fat stores and lastly to muscle protein.

Pretty much but the usage of the glycogen, fat, lactic acid (about 20% of the lactic acid you produce in steady state exercise is broken back down into glucose) and finally proteins can be controlled depending on your training level and current energy needs. It's not strictly a sequence of moving from one to the next.

 

[cewait]

I was just trying to get the point that carb loading as practiced by eating a double portion of spaghetti the night before a long run is not really doing the body good. All you are doing is creating a small hydration issue from the excessive digestion required from the high food input and that most Americans actually carb load as a matter of practice in their daily diets.

I agree that I over simplify the set of reactions in the body, but most folks will simply skip off if one gets dives too deep into the process. Imagine how confusing this can be if you are only trying to get folks to think fuel. Again, I try to keep this at a really high level on the forum as well as when I have a group cycling or running. I would lose folks if I did not keep it to fat and sugar.

The matra for the general public has to be improve the quality of fuel. One of the often repeated sayings I have for classes is When planning your meal you have the opportunity to fuel a Ferrari or a Yugo. What fuel to you want?

 

[rubato]

Understood!