The Arizona Marathon: Nutrition Resources

What is the thought process behind carbohydrate loading?

2009-01-25T16:07:00.000-08:00

Carbohydrates seem to be a controversial energy source lately. With the "low-carb" craze continuing, what do you make of the traditional spaghetti dinner the night before a race?

First of all, I'm not a big fan of the low carb information that is so typical in our media right now. The goal should always be to have a balance of all three macronutrients (carbs, protein, fats) in your diet. Second, depending on what kind of performance you are expecting from your body, carbs are very important.

If you are planning to walk the half marathon, you probably don't need to make major changes to your day-before-the-race intake. Just continue eating a balanced diet and hydrating properly. However, if you are planning to run a minimum of 1-3 hours on race day, pay attention! At this level of activity, our body changes the types of fuel it can use. Muscle glycogen (energy stored in our muscle cells) and plasma glucose (energy in our blood from the food we've eaten) are the primary energy sources during this time frame. This supports the idea of having a meal rich in complex carbohydrates the night before a race and providing adequate complex carbohydrates the morning of the race. So enjoy your pasta!

-Nicole

Should I take a vitamin supplement?

2008-11-29T08:35:00.001-08:00

One of the most common questions I receive is whether I recommend taking vitamin supplements. You must ask yourself several questions when considering taking a supplement. First, what kind of supplement are you considering? For a healthy individual, I would encourage a multivitamin supplement that provides a full range of vitamins and minerals over supplements that provide specifically one vitamin. The benefit of this type of supplement is that it can serve as a back-up to a great diet. No one eats a "perfect" diet, so making sure that you are giving your body everything that it needs is a good idea. Supplements do not replace the role of food, but they can compliment a full and varied diet to ensure excellent nutrition. Taking a specific vitamin supplement can be a little bit more difficult. In my opinion, this only becomes necessary if you have a specific health concern that requires it. Often single vitamin supplements provide more than 100% of the recommended intake, and sometimes this can be problematic. If you are considering taking a single vitamin, I would encourage you to talk to a dietitian or doctor about your situation.
Second, what are you hoping to gain from a suppplement? If you are hoping to help your body function at its peak ability, you are in luck! If you are hoping to provide additional energy for your body or help your body acheive a goal that just isn't realistic, you are going to be disappointed. Vitamins and minerals do not provide energy. Only calories (found in carbs, protein, and fats) provide energy.
So, perhaps you've decided to go pick out a supplement. What should you be looking for? In general, look for products that provide around 100% of the recommended intake. You don't need anything more than 100%, especially because you are also getting nutrients in your food. For the water soluble vitamins (all of the B vitamins), if you get more than 100%, your body will excreted the vitamins as urine. There is little risk of serious toxicity with water soluble vitamins. With fat soluble vitamins (A, D, E & K), there is a risk of toxicity because the body stores these vitamins instead of excretes them daily. You want to be especially careful with not over doing it with these vitamins.
A few other tips for picking out a supplement: more expensive is not always better- remember check out the percentages on the back; don't rely on the supplement to take the place of food- food is absorbed better and provides the energy; take your new supplement with a meal- it is easier on the stomach and will increase the amount of vitamins that are actually absorbed; and supplements are not regulated by the FDA so we don't have any guarantees- be sure to eat well!
-Nicole

Nutrient Density

2008-10-31T06:40:00.000-07:00

The concept of nutrient density basically refers to getting the most nutritional "bang for your buck". We know that all foods provide calories (energy). This is necessary for us to participate in daily life. However, food also provides vitamins, minerals, and other nutrients. The idea of choosing nutrient dense foods supports the practice of choosing food items that provide nutrients as well as calories. This seems like a no-brainer, but really it can often be overlooked. It requires us to look beyond the macronutrients (carbs, proteins, fats) discussed in the last blog and check out a food label.

When you look at a food label to check for nutrient density, pay attention to
the nutrients listed on the left hand side. In the example picture to the right, calories, total fat, cholesterol, sodium, total carbohydrates, and protein are the main categories listed. In the green portion, you will find a listing of vitamins. Directly to the right, you will find percentages in the purple column. This column can be helpful. It provides the percentage of the average daily need for that nutrient provided in the food. Now, this doesn't necessarily mean that the percentage will be exactly right for you, but it does tell you if the food is a good source of a given nutrient. Anytime you can maximize these percentages, you are looking at a food it is likely a good choice.

Stay tuned for more food label information!

-Nicole

The image used was reproduced for educational purposes only from www.health.gov

Nutrition Basics

2008-09-21T21:22:00.001-07:00

Before we begin talking about specific nutrition needs while training, let's make sure that we are on the same page with some nutrition basics. We get energy (calories) from carbohydrates, proteins, and lipids (fats). Each of these nutrients has a slightly different function.

Carbohydrates provide quick energy for our cells. We get carbs from foods such as cereal, pasta, breads, rice, fruits, and starchy vegetables (grain, fruit, and veggie groups). It is important to incorporate adequate carbohydrates into you diet on a daily basis. For most individuals, adequate carbohydrates means a minimum of 6-9 servings each day. You can maximize your nutrient density by choosing carbohydrates that are whole grain and high in fiber.

Proteins are the basic building blocks of our bodies. Protein foods include meat, fish, poultry, dairy, nuts, and legumes (meat, dairy, and veggie groups). We must have enough protein to maintain muscle tissue. This is especially important during training to be sure that our body is able to repair the damage that occurs during normal training. For many individuals, this is a minimum of 4-5 servings each day of protein foods including dairy. Most Americans meet our protein needs easily because of our portion sizes- you don't hear many people ordering a 2-3 ounce steak at a restaurant!

The last macronutrient group is the lipid group. I prefer to say "lipid" instead of "fat" because the word "fat" gives us the idea that fats in food will automatically be stored as fat in our bodies. This is not true. Lipids are a vital part of our diet. They provide energy and satiety as well as facilitate the absorption of fat soluble vitamins. Lipids are already incorporated into many foods we each such as some meat and dairy. We can also add lipids to our diets through use of oils, dressings, and butter. We should use the foods from this macronutrient groups sparingly, because these foods are calorically dense. This means that a little goes a long way.

Once you have an understanding of nutrition basics, it becomes easier to be sure that you are nourishing your body well!

Nicole

Hydration: Is it really that important?

2008-09-09T21:54:00.000-07:00

Hello everyone,

I think an important topic to begin with is hydration. We all know that in the Arizona heat we have to stay hydrated! With high temperatures continuing throughout the month of September, it is possibly more important to pay attention to hydration now than it will be in our race month of February when our temperatures will be more moderate!

Here is the deal on why hydration is so important. Sweating is the body's main mechanism of controlling body temperature during exercise. Picture this: You are training by running 5 miles today. As your muscles are utilizing glucose, they are giving off heat. This increases the temperature of the blood. The blood is carried to the surface of the skin. The skin temperature increases and perspiration appears on the surface. Through evaporation, the skin temperature is cooled as well as the blood under the surface. To be able to continue this process continually, you have to continue to provide your body with water to be used for sweating!

So hopefully you are sold on the idea that you need to remain hydrated. What should you use for hydration? Both water and sports drinks have a place, in my opinion. The presence of glucose (sugar) and sodium (Na) help the intestines to absorb water. This supports the use of sports drinks in addition to water alone. When you are choosing a sports drink, aim for about 6% of carbohydrate (CHO) and 80-120 mg of Na for each 8 oz serving.

To figure out the % of CHO take the g (grams) of CHO in a serving divided by the weight of 1 serving. For example, I looked at Gatorade Thirst Quencher (I'm not endorsing this specific product- I'm just using it for an example in how to figure out the information).

16 g carbohydrate/ serving

__________________= .0655 x 100 = ~6.5 % CHO

244 g (1 cup or 8 fluid ounces)

Hydration is an issue that you must continue to be aware of throughout your training, not just when you are actually working out. If you begin your run dehydrated, drinking an appropriate amount throughout your work out will not be sufficient. Here is a model of what adequate hydration may look like for you.

Throughout the day: 8 oz fluids with each meal & snack
Before working out: 8-16 ounces of water/fluid
During work out: 4-8 ounces of water/ fluid every 15-20 minutes *
After work out: 8-16 ounces of water/fluid*

*For the "during" fluids, I would encourage you to consider an energy drink if you are going to be exercising for greater than 60 minutes. For the "after" fluids, I would encourage the use of a sports drink that meets the criteria discussed earlier in the blog.

I hope this information is useful to you!

-Nicole

I consulted the following text while writing this blog: Krause's Food Nutrition & Diet Therapy 10th Ed. By L. Kathleen Mahan and Sylvia Escott-Stump

Welcome to the Nutrition Blog for the Arizona Marathon!

2008-09-03T19:18:00.000-07:00

Hello future marathoners!

I have been invited to provide you with nutrition information that will support you on your way to participating in the Arizona Marathon. I will post information that I think is nutritionally important for your training such as hydration issues, sports nutrition in general, and race day nutrition. Optimal nutrition is integral in your body's ability to perfom at its peak, so to race well we have to nourish well. I will also provide links to sites that I have found helpful in my own athletic career.

I look forward to seeing many well nourished and well hydrated runners on race day!

-Nicole