NUTRIENTS AND DIET Module 3- Metabolism and Nutrition

Macronutrient  A macronutrient is a nutrient that is required in significant amounts in the diet  Three macronutrients:  Carbohydrate  Protein  Fat (lipids)

Carbohydrate  Primary energy source in the body (provides 4 kcal/g)  Can exist as a mono/di/polysaccharide  All carbohydrate converted to glucose  Carbohydrate is stored as glycogen Converting glucose to glycogen is glycogenesis  Requirements:  General Population: 45-65% of total calories  Aerobic endurance athletes (>90 min/day): 8-10g/kg  Resistance/Power Athletes: 5-6g/kg

Carbohydrate  Simple vs Complex  Fiber  Men: 38 g/day  Women: 25 g/day  Prevents ketosis and is critical in sparing of protein as a metabolic substrate

Protein  “Building blocks” of all tissues, hormones  4 kcal/g  Exist as chains of amino acids  11 non-essential amino acids  9 essential amino acids  Recommendations  General: 10-15% of total calories  General Population: 0.8g/kg  Aerobic Endurance Athlete: g/kg  Resistance/Power Athlete: 1.7g/kg  Athletes (in general): 1.5 to 2g/kg

Protein  High Quality/Complete Proteins vs Low Quality/Incomplete Proteins  Recommended that at least 65% of protein in diet is high quality protein  Vegetarian/Vegan diets

Lipids  Function as membranes, hormones and hormone transport and energy stores  9 kcal/g  Bonds dictate type  No double bonds are saturated  One double bond are monounsaturated  Two or more double bonds are polyunsaturated  Recommendation  General Population: 20-35% of total calories  Athletes: 15-35% of total calories  Less than 10% of calories from saturated fat  Avoid trans-fatty acids or “partially hydrogenated” fats

Lipids  Good Fat?  HDL (high density lipoproteins) Help prevent CV disease Found in fish oil, flaxseed oil, fruits and vegetables, whole grains and beans  DHA Nervous system growth/restoration Pregnancy CV disease Found in fish (and their oils), game, seeds and plants

In-Class Assignment #11  Jane consumes 2000 calories per day. How much of each macronutrient should she consume per day?  Carbohydrate- 55% of total calories  2000 x 0.55 = 1100 calories from CHO  1100 kcal/4kcal/g = 275 g CHO  Protein- 20% of total calories  2000 x 0.2 = 400 calories from PRO  400 kcal/4kcal/g = 100 g PRO

In-Class Assignment #11  Fat- 25% of total calories  2000 x.25 = 500 calories from fat  500kcal/9kcal/g = 55.6 g fat

In-Class Assignment #11  Ed is a 220 lb strength and power athlete who consumes 4400 kcal per day. How many grams of each macronutrient does he consume and what is the percentage of total calories of each macronutrient?  220 lbs/2.2 lbs/kg = 100 kg  Carbohydrate  100 kg x 6 g/kg = 600 g CHO  600 g x 4 kcal/g = 2400 kcal CHO  2400 kcal/ 4400 total kcal = 54.5% CHO  Protein  100 kg x 1.7g/kg = 170 g PRO  170 g x 4kcal/g = 680 kcal PRO  680 kcal/4400 total kcal = 15.4%

In-Class Assignment #11  Fat  4400 total calories – 2400 kcal CHO – 680 kcal PRO  = 1320 kcal Fat  1320 kcal/9kcal/g = g Fat  1320 kcal/4400 kcal total = 30% Fat

Micronutrients  Nutrient that is required in small amounts (typically measured in milligram—or even smaller—quantities) in the diet  Two types of micronutrients  Vitamins Vitamins are organic substances (i.e., containing carbon atoms) that cannot be synthesized by the body They are needed in very small amounts and perform specific metabolic functions Table 10.5  Minerals Minerals are required for a wide variety of metabolic functions For athletes, minerals are important for bone health, oxygen-carrying capacity, and fluid and electrolyte balance Table 10.6

Micronutrients  Recommendations:  Same as general population  Vitamin C and D, iron, calcium and electrolytes (sodium chloride and potassium)  Be sure not to get to toxic levels

Hydration  Water is the largest component of the body, representing from 45% to 70% of a person’s body weight  Total body water is determined largely by body composition; muscle tissue is approximately 75% water, whereas fat tissue is about 20% water  Recommendations: Average Male: 3.7 L per day; Average Female: 2.7 L per day Athletes need 3-4 gallons (11-15 L) more than general population

Hydration  Risks of Dehydration Fluid loss equal to as little as 1% of total body weight can be associated with an elevation in core temperature during exercise Fluid loss of 3% to 5% of body weight results in cardiovascular strain and impaired ability to dissipate heat At 7% loss, collapse is likely  Monitoring Hydration Status Signs of dehydration include the following: Dark yellow, strong-smelling urine Decreased frequency of urination Rapid resting heart rate Prolonged muscle soreness

Pre-Competition/Training Nutrition  Food  Meal 2-4 hours before High in carbohydrate, moderate in protein, low in fat  Snack 30 minutes prior g CHO 4-8 g PRO  Hydration  1 pint (0.5 L) prior to competition

In-Competition/Training Nutrition  Food  Small amounts of CHO (4-6 g) and PRO (1-2 g)  Hydration  As needed (approximately every 15 minutes) in 8 oz doses

Post-Competition/Training  Immediately Post  6-8 g simple sugar  g PRO  75 g CHO  1-2 Hours After  Full meal (composition depends on competition/training schedule)  Hydration  Must replace every pound lost with 1 pint (0.5 L) of fluid