For the initial consultation, she calculated my daily calorie needs based on my weight, height, age, sex, and activity level. I also kept a food diary for 2 week days and 1 weekend day. She then constructed a 12-week meal plan to help me hone in on daily nutrition.
I have learned that it's not so much what you eat on race day or even the night before that affects performance; it's what you eat the weeks and months leading up to race day that matter. When I don't eat right, my performance suffers during training, and I have a hard time recovering. It can take up to a week to dig myself out of a hole--nutrition-wise or hydration-wise.
30 year-old female, 5'8", 130 lbs
Goal--hone in on Ironman nutrition for both training & race-day while maintaining optimum health, energy and fitness gains (gain muscle; no overall weight loss)
Specifics--figure out what works with a sensitive stomach
Energy Needs at baseline (not taking into account training): 2050 calories/day
1. eat several meals/day (4-6, 350-500 calories/meal)
2. eat a variety of foods (lots of different colors)
3. Hydrate properly (~65 ounces fluid a day at baseline, not including exercise; lots of water but juice and other fluids count as well)
1. cut back on sweets and saturated fats (who doesn't need to do this?)
2. increase fruits and especially veggies (again, who doesn't need to do this?)
3. increase protein (Yippee! More sushi!!!)
4. cut back on calcium (WTF? Apparently, with my love of dairy and calcium supplement (1000 mg/day), I was getting TOO much. Too much calcium can contribute to GI distress and actually leach calcium out of your bones. Who knew?)
Nutritional Considerations for Training:
Before: If workout lasts under an hour, need nothing. Beyond this, aim for 200-300 calories (mainly carbs) before starting. Personally, I love oatmeal and bananas. Also consume 1/2 liter of fluid. Do this 1-2 hours prior to workout.
During: Beyond 60 minutes of excercise, I need to replenish glycogen to prevent blood sugar from dropping (and the dreaded bonk). Aim for 200-250 cals/hr.
After: To speed recovery, eat within 30 minutes afer a workout (1/2 g carb; 1/8 g protein per pound of lean body weight; don't forget fluids and electrolytes! Chocolate milk is a complete post-workout recovery drink and meal)
Adjustments to Baseline Caloric Needs: For every 60 min of anaerobic and 90 of aerobic training, add 400 calories per day to my 2050 total caloric needs. Maintain same ratios of carbs:protein:fat. Don't forget electrolyte and fluid replacement! (See below).
On average, athletes lose 16 ounces of fluid (1/2 liters) per hour of exercise under cool conditions. 16 ounces=1 pound. (I'm not a big sweater, thankfully). The best way to calculate sweat rate is to weigh yourself before and after a workout. Don't forget to account for fluids taken in during the workout. You will sweat exponentially more when it's hotter. Performance likewise declines exponentially as fluid is lost. At 3% dehydration (3.9 lbs lost for me), performance has already decreased by 15%! Dehydration can lead to illness or even death so it is VERY important to hydrate properly. Unfortunately, or thirst response doesn't kick in until then, emphasizing the importance of drinking BEFORE you are thirsty.
1. Start your workout properly hydrated. This means drinking lots of water during the hours (and days) before workouts (eg 65 ounces daily, at baseline). It is recommended to drink 16 ounces of fluid 1 hour prior to exercise. Addition of 1/2-1 gram of salt in conjunction with water can increase absorption of fluid.
2. During exercise, drink 5-12 ounces of fluid every 15-20 minutes of exercise. A sports drink (containing elecrolytes and often carbs as well) is recommended for workouts lasting more than an hour. Remember, addition of electrolytes is just as important to prevent dehydration and can also increase fluid absorption and prevent GI distress.
3. Calculate your fluid needs based on weight lost during a workout. If you lose 16 ounces of fluid/hour, aim to sip 4 ounces every 15 minutes.
4. Adjust for conditions. Your need for fluid and electrolytes increases exponentially during hot conditions. The best way to calculate this is to weigh yourself before and after a workout in very hot conditions. Ironman Arizona will be hot and dry. Average temps are in the mid to upper 80s for the high in mid-April. I can expect need to 32-50 ounces of fluid an hour on the bike.
Race Day Nutrition:
I will get more into this as race day comes closer. Most of the nutrition is done on the bike since gastric absorption decreases so much on the run. Everyone's needs are different. But here's my preliminary plan:
InfinIT sports drink (contains complete set of carbs, protein, and electrolytes, customized for my needs)
Nuun Electrolyte Tablets
For the bike--at 17 mph, will take 6.5 hours. Need 1650 calories on the bike. Aero bottle will have straight water, which I can replenish at aid stations. 2 bottles on down tube and seat post will have InfinIT (3 heaping scoops/bottle=400 cals/bottle). Will replenish 2 InfinIT bottles at Special Needs.
For the run--will use 4-bottle Fuel Belt (each bottle has 8 ounces) containing water+InfinIT (low concentration). Supplement with Cliff Blocks (used 4-6 on 20 mile run at 62 degrees).
Race day will be hot, meaning I will have to rely more on liquid calories.
Thought this might help some of you guys out there training for an upcoming IM!