Calorie Requirements

In order to maintain a healthy weight one must eat an equal number of calories to the number of calories they burn daily. Active individuals have a higher calorie requirement due to the number of calories they burn during their workouts. These calories should be spread out throughout the day, and they should still come from nutrient dense foods most of the time (yes, one is allowed to indulge occasionally!). The percentages of calories from each nutrient may change slightly as such:

Carbohydrates in Exercise

If you have ever participated in or have observed a long lasting athletic event such as a marathon or triathlon, you have seen the athletes sucking down packets of a goo-like substance. This goo provides the athletes with, among other things, carbohydrates. As I explained in the carbohydrate section above, carbs are converted into ATP, which is our body’s energy currency. The first step our bodies take to get ATP is through a process called glycolysis. There are two types of glycolysis that our muscles use to make ATP during exercise: aerobic and anaerobic glycolysis.

Aerobic Glycolysis

Requires oxygen
Used in slow endurance activities
Examples: distance running and distance swimming
Pros: more ATP (energy) produced per carbohydrate molecule; No lactic acid produced during process
Con: slow process

Anaerobic Glycolysis

Does not require oxygen
Used in fast and explosive activities
Examples: weight lifting, sprinting
Pro: fast process
Cons: less efficient; fewer ATP produced per carbohydrate molecule

Lactic acid is a byproduct of this reaction; it will build up in muscles and give a burning sensation during the workout

Our muscles can store 30-35 grams carbohydrate per pound of body weight. This amount is sufficient for all daily functions plus a 30-60 minute workout. Marathon and triathlon athletes, however, know what “hitting the wall” feels like, which occurs when all of the muscle carbohydrate has been depleted, usually after 75-90 minutes of working out without any additional carbohydrate sources. In an attempt to prolong the time before hitting that wall, 15 grams of carbohydrates should be consumed every 30-45 minutes during exercise lasting longer than 1 hour.

If you are familiar with the glycemic index (GI) of foods, you know that not all carbohydrates have the same effect on our bodies. Some carbohydrates are called “complex carbs”. They are more fibrous and digest slowly, supplying a steady sugar source for the blood stream. Some sources of complex carbohydrates are whole grains and fibrous vegetables. These types of carbohydrates are excellent for your general health and weight maintenance. Other carbohydrates are referred to as “simple carbs”, and they supply a quick rush of sugar to your blood stream. Some food examples include candy, dried fruits, and those gooey gel packets that are consumed during endurance races. Here is a chart of some food’s glycemic indexes. The higher the number is, the more simple the carbohydrate, and the quicker the sugar rushes to your blood stream.

Food	Glycemic Index
Peanuts	1
Raw Cherries	3
Carrots	3
Skim Milk	4
Orange	5
Kidney beans	6
Whole Wheat bread	9
Apple juice	10
Banana	11
Gatorade	12
Sweet Potato, boiled	18
Fruit Loops	18
Power bar, chocolate	24
Lender’s bagel, white	25
Baked potato, russet	26
Raisins	28
Skittles	32
Dried dates	42
Power bar energy gels	89

According to Monique Ryan’s book “Sports Nutrition”, there are three keys to carbohydrate intake for the athlete; timing, amount, and type.See the Pre-run, Mid-run, and Post- run sections below for meals and snacks containing the right type and amount of carbohydrate needed to maximize your performance for each time of day.

Many endurance athletes practice “carb- loading” which trains their muscles to absorb and store more carbohydrates than normal. If done properly carb loading can prolong one’s energy source and prevent the “hitting the wall” effect. This process begins during the taper of training, 2-3 weeks prior to the big race. The athlete’s carbohydrate intake gradually decreases with the number of miles the athlete is running, down to about 30-40% of their total caloric intake. A large amount of carbohydrates are taken in the day or two prior to the race with the idea that the muscles are craving carbohydrates, and will absorb more than normal. Here is a useful article on Mayo clinic’s website about carb-loading:

http://www.mayoclinic.com/health/carbohydrate-loading/MY00223

Proteins and Exercise

Protein’s role during exercise can be thought of like an engine in a car. Without the protein in our muscles we would not be able to exercise, and without an engine a car wouldn’t be able to move when the gas pedal is down. Much like the wear and tear that an engine takes on long road trips, muscles pay a price for hard bouts of exercise. The proteins in our muscles break down during and after exercise. In order to repair the muscle and gain the full benefits from exercise muscles require recovery and proper nutrition following the exercise period. Refer to the “Post run foods” section below for snacks that contain proteins that are great for mending your muscles for your next run.

I must touch on the subject of protein supplements. What you really must know is that they are not needed to improve performance. The truth is that any protein intake above your requirement is stored as fat! So, save your money and your body, and go without the protein supplements.

Fat’s Role in Exercise

There is a lot of talk about fat burning exercises in today’s fitness media. Though it isn’t as efficient to burn fat rather than carbohydrates during exercise, they are very important in preserving our carbohydrate stores. Fat provides a higher percentage of the energy needed during long duration exercises. A well trained endurance athlete will burn a higher percentage of fat than a normal person in the same workout. Here is a chart that might represent the percentage of energy provided by each macronutrient during exercise for an average person.

Foods containing high amounts of fat should be avoided before, during, and immediately after exercise. Fats slow digestion, and can feel heavy in one’s stomach which would hinder performance during a workout or race. Consumption of omega- 3 fats during meals has been shown to reduce inflammation throughout the body, including inflammation caused by exercise. Remember… quality, not quantity!

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