Thursday, August 20, 2009

Why Are Carbs So Good?

One big reason carbs are so good is that it's the only fuel that the brain can use. That's actually one of the reasons why you hit the wall around mile 20 in a marathon. When your brain realizes that you're just about about out of glycogen (the form in which carbs are stored in the body for fuel) the brain can actually send messages to begin fatiguing your muscles in an attempt to slow you down. It's basically a self-preservation mechanism kicking in because the brain needs some of that fuel too in order to function.

Carbs are stored in the muscles and liver in the form of glycogen. Glycogen is the most efficient fuel your body burns for energy. Carbs are also loaded with B vitamins, chromium, fiber, iron, magnesium, and phytochemicals (which come from plant nutrients) all of which are important to good health and can even help prevent many cancers.
Pick your carbs wisely. Most of your carb intake should be from complex carbohydrates. Complex carbs are usually from unprocessed, unrefined, whole grains. So instead of white rice, eat brown rice. Instead of white bread each whole grain bread, etc. They take longer for your body to digest and because of this complex carbs will stay with you and provide energy for the long haul. Most of the early part of the carb-loading phase before the race will consist of eating complex carbs.

Simple carbohydrates are food products that are made of processed and/or refined grains. Because they have been processed and refined, they are digested very quickly and provide quick energy. Sugary soft drinks, white rice, sugar, candy, and fruit are examples of simple carbs. Don't avoid simple carbs completely, however. For example fruits are simple carbs, but they are nutrient dense foods that provide many different vitamins as well as fiber. Simple carbs, because they are processed so quickly, do raise the blood sugar levels really quickly. That's why when you eat a candy bar you feel a quick boost of energy, but then soon after crash. Simple carbs tend to have a high GI (a rating using the Glycemic Index) and complex carbohydrates tend to have a lower GI. Foods considered high are 70+ on the GI scale, 56-69 are considered medium, and under 55 are considered low. [Click here] to find out more about the Glycemic Index.

As a runner, eating foods with a lower GI will provide you a better source of energy for the long haul. But simple carbs do have their place. Eating simple carbs shortly before a race can provide quick energy that will be used and if you have stock up prior to the race on complex carbs, you shouldn't feel that crash. Also during the race, using gels and sports drinks (which usually contain a combination of simple and complex carbs) and be used quickly by the body and provide that needed energy later on in the race when your glycogen stores begin to get depleted.

Note: If you are diabetic or have other health concerns, consult with your doctor before making any dietary changes.


Unknown said...

This is very helpful. I have been struggling to find which foods help me the most especially when doing the long run. I tend to slow down after doing 22-23 miles into marathon.

Unknown said...

Nice article what about pasta? Somehow i never eat pasta thinking it is pure carbs and not good for me. Mentally i avoid carbs like bread rice even potatoes even though i know it is good for me.
I do eat fruit though.

RunnerDude said...

Hey Ted! Welcome to the blog! Glad it helped! Are you training for any upcoming marathons?

RunnerDude said...

Hey Ness! Pasta is fine during carb-loading. Also Whole grain pasta is a complex carb and those are better for you. Muellers makes a line of whole grain pasta that's really good. It's not that thick chewey pasta like lots of whole wheat pastas are. Remember that whole grain bread are good too. Carbs are your fuel, so if your eating the "fuel" and then burning the "fuel" there's no danger of it going to fat. So eat you some carbs!

Unknown said...

Hey RunnerDude.. Yes, I am working toward my #7 marathon: Amica Newport (Rhode Island) marathon this October.

I am sort of having a mental issue. My average time in completing the past marathon is about 4:30. With half marathon, I can go all out and get it under 1:45. With marathon, I'd usually bonk out around 22-23 miles.

When I am doing my 5 or 6 miles, my average pace is between 7:45 to 8:30 pace.

Your recent post is very instrumental in term of what I need to eat to prepare for the marathon. My problem is that I read too many materials and cannot figure out which one to use. Terrific post!

I have put your blog in my Bloglines.

RunnerDude said...

Hey Ted! Could be a pacing, endurance, or a fuel issue. Email me at so I can get a little more info about your trainining.

Tanya said...

I'm currently ramping up my good carbs level; my current favorite is whole grain pasta with a heart healthy pasta sauce. Toss in a little diced grilled chicken and I'm good to go-I've been known to eat this even for breakfast!

RunnerDude said...

Hey Tanya! I think we're twins separated at birth! LOL! That sounds delicious!