Nutrition---Fueling The Engine!

Fueling the Engine for St.Anthony's

A Perfect Nutrition Plan for any Olympic Distance Triathlon

Marni Rakes, M.S., CISSN

Among the many North America, multi-sport events, the 24th annual St. Anthony's Triathlon distinctly signifies the commencement of the triathlon season. Featuring the best professional triathletes around the globe and an opportunity to qualify for the 2008 World Championships, racing in St.Petersburg, Florida on April 29th, is not only a priority but a privilege. In light of this, however, the chance to successfully register before the race reaches capacity is just as competitive as the competition.  Registration usually closes within five hours!  So, whether you are hopeful for a slot for age group nationals or considering the thought of finishing your first Olympic distance triathlon, the excitement is building for the premier race of the triathlon season.

            Seeing that it is well into the New Year, and your time for making holiday weight gain excuses is far beyond the expiration date, finish up the recommended boring base mileage and start buckling down on your training nutrition. Learning about the importance of race day nutrition is one thing, but applying and perfecting your individualized nutrition plan is an opportunity to take your training and racing to a whole new level.

            Consider sports nutrition as an integral part of your training plan. Being a successful triathlete involves more than intense training, adequate rest and recovery and plenty of stretching. In part of being a triathlete, you daily caloric needs should be top priority in your training program. Although the multiplicity of "healthy" foods, sport drinks, gels and bars can be very confusing, let variety be your ally and learn the proper way to eat. With less than two months until race day, start experimenting with your new and controlled nutrition plan.

Why Nutrition?

            Although so many people complain about how hard sports nutrition is to understand, nutrition is one of the easiest components of your training to control. While you have no control of the heat, waves, blisters, stomach problems, cramps, start time, flat tires and too many fast people on the course, you have total control of what you put in your mouth. You have the option of sports drink or energy gel. What more do you need?  

            The interesting fact behind sports nutrition is that there isn't a specific controlled regimen for all triathletes to follow. For some athletes, rolling out of bed to start a 5:30 a.m. run on an empty stomach is a typical routine, while others allow at least an hour for a complete digestion of a piece of toast. We all know people like that, right? But with good reason, we should plan our nutrition routine to accommodate our lifestyle, training habits and dietary desires. So, with the following article, use these suggestions as guidelines to follow in an effort to fuel your active body.

Carbohydrates and the Glycemic Index           

            During exercise you burn predominately glycogen, the storage form of carbohydrates. As a competitive and active triathlete, carbohydrate consumption is vital for keeping you well-energized for all your weekly training sessions. Unfortunately, because every carbohydrate behaves differently in the body, it is necessary to consume only the best source of carbohydrate to maintain an adequate level of blood sugar. Therefore, prioritize the best type of carbohydrate to stabilize your fluctuating blood sugar levels.           

            Originally created as a tool for diabetics, the Glycemic Index (GI) is an effective method of ranking foods in reference to their overall effect on blood glucose levels. Once a carbohydrate food is consumed, depending on its low or high GI ranking, it will respectively produce either a small or great rise in blood sugar and insulin levels. In turn, you will experience a major effect (either positive or negative), thus contributing to your mood, appetite, exercise and overall health.            

            The process of breaking down and converting carbohydrates for fuel is simple. After food consumption (which is no problem for an athlete), the body will create several enzymes to digest food and a repercussion of sugar (glucose) will enter the bloodstream. As muscle glycogen stores deplete during exercise, the body relies on liver glycogen and correspondingly, blood glucose levels drop.  The body reaches a state of hypoglycemia (low blood sugar) if blood glucose levels fall to low (i.e. long periods without eating or excessive exercise), and the brain will release hormones forcing you to feel hungry, tired, dizzy or week. Intentionally, you may sense hunger, with the purpose of forcing the body to consume food and produce the necessary glucose. In contrast, if blood levels rise (i.e. eating processed or simple sugar carbohydrates), the pancreas will release insulin in order to take up the excess glucose. In the later case, a dramatic rise in blood sugar ("sugar spike") will force the body to release an abundant amount of insulin and blood sugar levels will dramatically decrease. Whereas an occasional change in blood sugar is tolerable, extremely high or low levels of insulin may create serious and detrimental health problems.

How Much?

            Because the body stores carbohydrates in limited quantities, it is important to eat throughout the day.  Aim to eat 5-7 small meals in order to keep your blood sugar stable and energy stores packed. As the intensity and duration of your exercise increases (more than 85% max heart rate or more than 60-90 minutes of exercise), the need for more carbohydrates also increases.

            On a daily basis, eat 60-65% of your total calories form good sources of complex carbohydrates. For a 2000 calorie diet, this would be approximately 1200 calories from carbohydrates. Because each gram of carbohydrate provides your body with 4 calories, you will need to eat around 300 grams worth of carbohydrate to meet your daily recommendations. To make it easier, aim for 5-10 grams of carbohydrate for every kilogram (kg) of body weight (lbs / 2.2 = kg).  

High or Low GI?

            The secret to an optimal training session, and an overall improvement in your health, is how to recognize and appropriately consume low and high GI carbohydrates. Low GI carbohydrates, which break down slowly and produce a small fluctuation in blood sugar levels, are given a low ranking on the GI scale. In contrast, carbohydrates which are digested quickly and produce a rapid rise in blood glucose levels are termed high GI carbohydrates and are given a high value on the GI scale.

            In reference to many published research studies, low GI carbohydrates are an ideal pre-training/racing snack. In addition to encouraging the oxidation of fat, rather than increasing the rate of muscle glycogen utilization, low GI carbohydrates support a better balance of blood glucose concentrations during your longer training sessions.  Immediately after your workout, however, hormones are elevated and blood glycogen levels are at their lowest. In order to increase plasma glucose and insulin concentrations and encourage the re-synthesis of muscle glycogen, the optimal post-training snack should be higher on the glycemic index.

Contributing Factors

Seeing that many factors contribute to a carbohydrates ranking on the GI scale, it is unreasonable that you would remember the GI of every food in your diet. As a dedicated, type-A triathlete, however, I wouldn't be surprised if you tried. Nonetheless, it is very important to recognize when to eat certain foods, why you are consuming them and specifically what to eat before, during and after training. The following factors may contribute to the GI index:

  • Refined, enriched (less refined = low GI)\
  • Fiber (more soluble fiber = low GI)
  • Protein (more protein = low GI)
  • Cooking (al dente/less time = low GI)
  • Stomach emptying (fiber in gut, acid in stomach = low GI)
  • Fat (more unsaturated fat = low GI)

Sweets - The Good Stuff!

            While though the ongoing excuse of "I burned it off during training" will usually work in your favor, the rule of the GI index is a valuable tool for keeping your body in racing shape. I will not deny that being an active triathlete has its benefits. Have you ever seen a post-race food table? Likewise, because I am a big devotee of the popular post-training pizza, pancakes and/or ice cream, it would be wrong of me to tell you to avoid all sweets and simple carbohydrates from your diet.  However, choose your "junk" food wisely and try to minimize or remove all products from the diet. Processed foods, with a prolonged shelf life, and most baked and fried goods often contain unhealthy partially hydrogenated oils and trans fatty acids, which are extremely harmful for your cardiovascular system.             

            Starting today, establish a new and controlled eating plan by timing the intake of your favorite low and high GI foods. Save the sugary sweets for an immediate post-workout snack and with no remorse, enjoy your favorite treat with a healthy smoothie of whey protein or milk. And as a bonus tip, be sure to eat a small helping of protein (i.e. nuts, cheese) or fiber (apple slices, figs) before a meal or snack, in an effort to offset the surge of blood sugar that occurs when eating carbohydrates. 

What Do I Need to Eat?

            With your new eating plan comes a goal of regulating blood sugar levels. You must learn how to eat intuitively and recognize the needs of your body.  In other words, eat frequently, include protein and fat at all meals and control portions when snacking. 

            Higher GI foods are best eaten in the earlier part of the day, and above all, during and after a workout. In contrast, lower GI foods should be consumed in the later part of the day and are favorable at least 30-minutes to an hour before a workout. Additionally, your appetite, cravings and waistline will greatly appreciate a regular intake of low GI foods.
            Based on the GI scale, the following carbohydrates are appropriate to eat before training, and on a daily basis, to keep your blood sugar levels in check.

  • 100% Whole wheat, rye or stone-ground bread
  • Oats, oatmeal
  • Whole grain/High fiber cereals
  • Whole wheat pasta (al dente)
  • Brown rice, couscous
  • Lentils
  • Vegetables (carrots, peas, asparagus, broccoli, corn) *watch for gastrointestinal upset when training
  • Beans
  • Fruits (figs, apples, pears, prunes, apricots, ripe bananas)

What about Protein?

      Although dietary protein is not a direct energy source, protein is a great way to control your appetite and foster a speedy recovery after exercise. Due to the constant wear and tear on your body, your muscles require necessary amino acids (building blocks of protein), in an effort to repair and rebuild damaged tissues after training. In order to improve training, research shows that consuming a protein beverage in the first 30 minutes after exercise not only repairs damaged tissues, but helps to restore glycogen levels to support your subsequent training sessions. Immediately after exercise, when your body is very sensitive to the hormone insulin, digested carbohydrates will be quickly taken up by the bloodstream to restock glycogen storage. Because your body will quickly absorb most, if not all, digested nutrients after exercise, combine protein with carbohydrates in an effort to repair any damaged tissues.  Aim for a 150 - 200 calorie liquid carbohydrate-protein snack immediately after exercise.  For example, add whey protein to a glass of milk, eat a yogurt with a handful of almonds or have some egg whites with a piece of toast.  For vegetarians, who struggle consuming complete proteins, such as fish, lean meats and eggs, be sure to eat complementary proteins, such as lentils with spaghetti, tofu added to vegetables or beans on top of your salad.

      Similar to carbohydrates, each gram of protein provides four calories.  Although daily recommendations suggest 1.2-1.4 g/kg/day of protein for active individuals (while sedentary people should aim for .8 g/kg/day), endurance athletes should consume 1.4-1.8 g/kg/day.  Aim for a protein intake at around 20-25% of your total daily calories and be strict with your protein consumption immediately after exercise. The following foods are great options for meeting your daily protein requirements. 

  • Fish (salmon, tuna)
  • Lean meat/soy meat
  • Nuts
  • Skim/Soy milk
  • Whey/Soy protein
  • Low-sugar yogurt
  • Low-fat cheese
  • Low-fat cottage cheese
  • No sugar added ice cream
  • Eggs (1 yolk per 2 whites) / Egg substitute     

Good Luck!

      When preparing for a triathlon, your nutritional plan is only one portion of your training plan. Start your new nutrition plan by learning how to eat intuitively and control what and when to eat. No matter what distance triathlon you are racing this season, proper nutrition is essential for achieving the most favorable race performance and an optimal recovery.  Seeing that your St.Anthony's race appearance will last less than 4 hours, much of reaching the finish line will be heavily on your physical training. The best of luck in your training and nutrition routine and I'll see you at the finish line!

Marni Rakes is an active endurance triathlete who holds a Master of Science in Exercise Physiology and is certified sports nutritionist. Marni is currently serving as the USAT Florida Region Director and is a USAT Level-1 Coach. Marni recently finished her first Ironman (Ironman Florida) and qualified to compete in the Ford Ironman World Championships in Kona, Hawaii on October 13, 2007. Any questions regarding this article, training or nutrition please contact and visit