The Physiology and Time Factors involved with the Nutrition and Digestion

for Athletes: Pre-activity and Post-Activity meals and How to Design Meals

Brady JonesDeRon Jenkins Courtney Jones

The Digestive Tract

◦ Digestive System basics Organs of the GI Tract

Mouth Esophagus Stomach Small intestine Large Intestine

And Some accessory organs (Gallbladder, Pancreas, Etc.)

The Physiology of Digestion

Nutrition◦ The Science of how living organisms obtain and use

food to support the process required for life.

The Transformation of Food Breakdown of food through Catabolic Pathways Absorbed Rebuilds through Anabolic Pathways

3 Major types of food Proteins Carbohydrates Lipids

Purpose of the GI Tract

Defined as: A Nitrogen containing Macronutrient made from amino acids

Often called the building blocks of the body Basic Functions

◦ Combined to make muscle, bone, tendons, skin, hair, and other tissues

◦ Nutrient transportation and enzyme production 2 types

◦ Complete-(Includes all 8 of the essential amino acids)

◦ Incomplete-(lacks one or more essential amino acid)

Proteins

Athletic Need for Protein◦ Athletes need protein primarily to repair and

rebuild muscle that is broken down during exercise and to help optimizes carbohydrate storage in the form of glycogen

◦ Protein isn’t an ideal source of fuel for exercise, but can be used when the diet lacks adequate carbohydrate This is detrimental, though, because if used for fuel,

there isn’t enough available to repair and rebuild body tissues, including muscle.

Proteins (Cont.)

Defined as: An organic Compound made up of varying number of Monosaccharides.

Carbs are arguably the most important source of engery for athletes◦ No Matter what Sport

Carbs Provide energy for muscle contraction

Carbohydrates

Pathway of Carbs◦ Once eaten, carbohydrates breakdown into

smaller sugars (glucose, fructose and galactose) that get absorbed and used as energy Any glucose not needed right away gets stored in the

muscles and the liver in the form of glycogen Once these glycogen stores are filled up, any extra gets

stored as fat. Primary Source of energy for Exercise

◦ Glycogen ◦ Short Intense Burst of energy (Sprinting, Weight

Lifting) because it is immediately accessible

Carbohydrates (Cont.)

For Long endurance based activity ◦ Glycogen is used as well as Fat

Adequate carbohydrate intake also helps prevent protein from being used as energy

Replenishing the Energy Stores◦ If we don’t replenish the stores we can run out of

fuel for immediate exercise Referred to as “Hitting the Wall”

Carb-Loading◦ Is a planned, well-timed depletion and Intake of

high level of carbohydrates before a competition

Carbohydrates (Cont.)

Defined as: An Organic Substance that is relatively insoluble in water

and soluble in organic solvents. Negative Connotation

◦ Essential to optimal Health Adipose Tissue

◦ Stored Fat◦ Provides cushion for internal Organs

Fat provides the highest concentration of energy of all the nutrients

Lipids

3 types of Dietary Fat◦ Saturated Fats

This type of fat is often solid at room temperature found primarily in animal sources like meat, egg

yolks, yogurt, cheese, butter, milk◦ Unsaturated Fats

liquid at room temperature which are typically found in plant food sources

◦ Trans Fat Trans fatty acids are created (naturally or man-made)

when an unsaturated fat is made into a solid

Lipids (Cont.)

Ensure that athletes have adequate fluids during periods of active training and competition.

Provide adequate calories to meet growth and development needs (if in youth and adolescent years).

Provide calories to meet extra needs of physical activity.

Supply nutrients from food. Instill sound nutrition principles and practices

that will last a lifetime.

Goals Of Nutritional Care For Athletes

Design a meal pattern that fits your daily routine. Plan to eat at least three times a day. Use snacks between regular meals to help meet caloric and nutrient needs.

Eat a diet rich in complex carbohydrates (starches). Starchy foods such as pasta, breads, cereals, potatoes, corn, peas and others provide a major energy source to fuel your activities. These foods are also a source of fiber, vitamins, and minerals.

Drink sufficient fluids to stay hydrated during training and competition periods - don't wait until you are thirsty to drink.

Eat a diet that contains a variety of foods from breads and cereals; fruits; vegetables; meat and meat substitutes, and dairy groups. It is your best insurance for getting needed nutrients.

Good Eating Habits For Athletes

A pre-game meal three to four hours before the event allows for optimal digestion and energy supply. Most authorities recommend small pre-game meals that provide 500 to 1,000 calories.

High-sugar foods lead to a rapid rise in blood sugar, followed by a decline in blood sugar and less energy. In addition, concentrated sweets can draw fluid into the gastrointestinal tract and contribute to dehydration, cramping, nausea and diarrhea. Don't consume any carbohydrates one and a half to two hours before an event. This may lead to premature exhaustion of glycogen stores in endurance events.

Regardless of age, gender or sport, the pre-game meal recommendations are the same. Following a training session or competition, a small meal eaten within thirty minutes is very beneficial. The meal should be mixed, meaning it contains carbohydrate, protein, and fat. Protein synthesis is greatest during the window of time immediately following a workout and carbohydrates will help replete diminished glycogen stores.

Pre-Activity Meal

Eat lightly before an athletic competition. Eat complex carbohydrates and keep

protein and fat intakes low since these are slow with digestion.

Avoid bulky foods. They may stimulate bowel movements. Bulky foods include raw fruits and vegetables, dry beans and peas, popcorn.

Avoid gas-forming foods such as vegetables from the cabbage family and cooked dry beans.

Eat slowly and chew well.

Pre- Activity Meals

Drink water to be adequately hydrated. One suggestion is to drink 2 1/2 cups water 1 to 2 hours before the event. Follow this by drinking about 1 1/4 cups water 15 minutes before the event.

Avoid drastic changes in your normal diet routine immediately prior to competition. Some athletes prefer to use favorite foods which may give them a psychological edge.

Pre-Activity Meals Contd.

Eat carbohydrate-rich foods and beverages as soon as possible after competition. They will replenish glycogen stores quickly and get the athlete back into performance shape. Fruits, juices, high carbohydrate drinks, pop are examples.

Replace fluids that have been lost. For every pound that is lost, drink 2 cups of fluids.

Replace any potassium or sodium that has been lost during competition or training by using foods. Fruits and vegetables are excellent sources of potassium. Replace sodium by eating salty foods.

Return to your normal high carbohydrate diet at your next meal.

Post Activity Meals

Breakfast Milk, fat-free 12 ounces 125 Calories Nutty barley cereal 1 cup 94 400 Calories Cinnamon raisin bagel 194 Calories Reduced-calorie margarine 1 tablespoon 50

Calorie        Morning snack       Granola bar with oats, sugar, raisins and coconut

2 (1 1/2 ounces total) 180 Calories Grape juice, unsweetened 12 ounces 227 Calories Carrots, baby (12-10) 42 Calories

Sample Meal Plan For an Athlete

Lunch       Milk, fat-free 8 ounces 84 Calories Whole-wheat bread 4 slices (1 1/2 ounces per slice)

440 Calories Chicken breast, roasted without skin 3 ounces 140

Cal. Romaine lettuce, shredded 1/4 cup 2 Calories Mayonnaise-type salad dressing 2 tablespoons 57

Calories Tortilla chips, baked 1 ounce 110 Calories        Afternoon snack       Low-fat fruit yogurt 8 ounces 250 Calories Wheat crackers (10-19) 142 Calories Apple, medium 72 Calories

Sample Meal Plan Cont.

Dinner       Salmon, baked 4 ounces 233 Calories Brown rice 1 1/2 cups 337 Calories Broccoli, steamed 1 cup 52 Calories Milk, fat-free 8 ounces 84 Calories Lettuce salad with tomatoes and carrots 1 1/4 cups 16 Calories Low-calorie Italian salad dressing 2 tablespoons 15 Cal. Walnuts

1/4 cup 196 Calories         Evening snack       Banana 105 Calories Fig bars 110 Calories Frozen yogurt, fat-free (not chocolate) 1 1/2 cups 285   Calories

Total Calories for the day:  3,948    

Sample Meal Plan Cont.

During Michael Phelps’ run for 8 gold medals he ate 12,000 calories a day. Here is his meal regimen.

Breakfast: Three fried-egg sandwiches loaded with cheese, lettuce, tomatoes, fried onions and mayonnaise. Two cups of coffee. One five-egg omelet. One bowl of grits. Three slices of French toast topped with powdered sugar. Three chocolate-chip pancakes.

Lunch: One pound of enriched pasta. Two large ham and cheese sandwiches with mayo on white bread. Energy drinks packing 1,000 calories.

Dinner: One pound of pasta. An entire pizza. More energy drinks

Fun Fact

No Two people are going to have the same Ideal Meal◦ Factors

Types of Activity Endurance Vs. Strength

Athletes Body composition Type of Athletes

Endurance (Marathon Runner, Swimmers, Etc) Strength (Sprinters, Power lifters, Etc)

Ideal Meal