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Nutrition forPerformance and Weight Control
Adam Pennell MS, CSCS, SNS
Energy
Energy Density
Carbohydrate Protein Fat Alcohol0123456789
10
Macronutrient
kcal
/g
Estimating Energy Expenditure
• Revised Harris-Benedict Formula1
– Basal metabolic rate (BMR)– Activity factor (AF)– Total daily energy expenditure (TDEE)
Estimating Energy Expenditure
• Revised Harris-Benedict Formula1
– Men• BMR = 88.362 + (13.397 x weight in kg) + (4.799 x
height in cm) - (5.677 x age in years)
– Women• BMR = 447.593 + (9.247 x weight in kg) + (3.098 x
height in cm) - (4.330 x age in years)
Estimating Energy Expenditure
• Revised Harris-Benedict Formula1
– TDEE = BMR x AF• Little to no exercise Daily kilocalories needed = BMR x 1.2• Light exercise (1 – 3 days/week) Daily kilocalories needed = BMR x 1.375• Moderate exercise (3 – 5 days/week) Daily kilocalories needed = BMR x 1.55• Heavy exercise (6 – 7 days/week) Daily kilocalories needed = BMR x 1.725• Very heavy exercise (twice/day, max ex) Daily kilocalories needed = BMR x 1.9• Pregnancy Daily kilocalories needed = +300• Lactation Daily kilocalories needed = +500
Energy Expenditure
• Resting metabolic rate (RMR)2
– 60 – 75% daily energy expenditure• Thermic effect of activity (TEA)2
– 15 – 30% daily energy expenditure• Could be even higher in extremely active individuals
• Thermic effect of feeding (TEF)2
– ~10% daily energy expenditure
Nutrition Strategies
Macronutrient Contributions
• A well balanced diet should consist of the following macronutrient percentages– Ranges vary for individual demands/goals
• CHO 55 – 65%• PRO 15 – 25%• FAT 15 – 25%
*Per day, not per meal necessarily
Diet Analysis
• Female, 22 years old, 120 lbs, 5’3”– BMR = 1,352.4– AF = 1.375 (light exercise; 1 – 3 days/week)– TDEE = 1,352.4 x 1.375 = 1, 860 kcal
60% CHO1,116 kcal
279 g
20% PRO372 kcal
93 g
20% FAT372 kcal
41 g
Low CHO Diet
• Glycogen– Stored CHO– Extremely important energy substrate– Requires water retention• 2 – 4 g of water/1 g CHO3-5
– Low CHO diet = ↑ water loss
Low CHO Diet
• Insufficient CHO intake leads to depleted glycogen, blood glucose– Brain, nerves, blood, are fueled by CHO
• Fat cannot be converted directly to glucose• Glucose is then created via non-ideal
pathways– Glycerol from triglycerides– Muscle degraded to create CHO
Low CHO Diet
• Fat breakdown is dependent on CHO presence • ↓CHO
↓ pyruvate↓ TCA cycle intermediates
↓ TCA cycle↓ fat catabolism
• “Fat burns in a CHO flame”
Low CHO Diet
• ↑ protein↑ nitrogen
↑ deamination ↑ ammonia
↑urea ↑ water loss
Carbohydrate: C-H-O Protein: C-H-O-N
Low CHO Diet
• Protein is a horrible energy source• Only a small contribution (~2%) to total energy
production during exercise6
– May increase to 5 – 15% late in prolonged-duration exercise
Low CHO Diet
• Diuretic• Depletes glycogen• Promotes incomplete fat mobilization• Promotes muscle degradation • Promotes central fatigue• Potentially high in saturated fat, fat• Potentially low in micronutrients, fiber• Potentially costly
Low CHO Diet
High PRO7
61.2%35.0%3.8%
Mixed7
37.1%59.5%3.4%
Starvation7
60.9%32.4%6.7%
W:F:P:
Energy Expenditure
• Thermic effect of feeding (TEF)– More meals = increased energy expenditure?• False8-10
• Likely helps curb cravings, hunger though
Calorie Shifting
• Keep your body/metabolism guessing?– Anecdotal and no real research, however…• Could be used as a good base
– Don’t have to stress about calorie content of each meal
• Could promote a well-rounded diet– Not eating the same foods
• Should not use extremes
Nutrition for Weight Loss
Underfeeding
• Caloric decrease should be modest to maximize weight loss, minimize hunger, and maintain physiological functioning – ~500 kcal/day is generally suggested• Equates to 1 lb/week
– Women should consume at least 1,200 kcal/day11
– Men should consume at least 1,800 kcal/day11
Exercise
• Easiest way to provide a negative energy balance– Cutting calories in the diet is not always an option– Typically cardiovascular exercise
– Also weight training, interval training, etc.
Weight Loss
• Weight loss is a gradual process• It takes ~4 weeks to establish the desired
pattern of fat loss for each pound of weight loss12
Fat Storage
• Reference man13
– 15% body fat• 12% storage• 3% essential
• Reference woman13
– 27% body fat• 15% storage• 12% essential
Nutrition for Weight Gain
Resistance Training
• Must overload/stress the body– Consistently
• Muscle growth is gradual and highly individual14-16
• 12 weeks (+/-) for untrained individual• Chronic resistance training typically leads to 0 – 1
kg/month increase in fat-free mass
Overfeeding
• Typically only 30 – 40% of weight gain is fat-free mass15,17-18
• Caloric increase should be modest to maximize muscle-to-fat gain– 300 to 500 kcal/day19
– 55 – 60% should come from CHO19
Practical Performance Recommendations
Pre-Exercise
• 1 – 4.5 g/kg CHO19
– 2 – 4 hours prior– Complex CHO, low glycemic index
220 lbs = 100 kg100 x 1= 100 g100 x 4.5 = 450 g
100 – 450 g CHO
During Exercise
• 1 g/min CHO19
– Generally not necessary if <60 minutes
Post-Exercise
• 6 – 20 g PRO19
– Within 15 – 30 minutes– Quality and a combination of proteins are likely
the best factors– Protein in excess of 20 g irreversibly oxidized
Hydration
• 2 – 3 cups/lbs lost19
– Pre/post dry bodyweight– Monitor urine color
Chocolate Milk• Nature’s engineered recovery beverage• Provides fluid• Cheap
– ~$5/gallon (CA prices in 2013)• Serving
– 1-2 cups depending on needs– ~$0.32/cup
• CHO:PRO ratio– 3:1 – 4:1
• For lower ratio (anaerobic) you can “cut” with plain milk or use less chocolate• For higher ratio (aerobic) you can add chocolate
• Casein, whey protein 8-11 g/cup• High glycemic index 25-30 g/cup• Fat-free 0 g/cup• Low-fat 2.5 g/cup
– Not ideal but a small amount of fat will likely not delay gastric emptying too significantly• Vitamins/minerals
– Calcium, vitamin D, sodium, potassium, etc.
Supplements• Completely unregulated industry
– Too much?– Too little?– Safe?– Purity?– Cost?– Adverse effects?– Spiked?– Tainted?– Contamination?– No research?– Bad research?– Research sponsor?– Marketing?
Lifestyle Nutrition
Basic Nutrition Strategies
• Moderation• Variety– “Colorful” plate• High in fiber• High in nutrient-dense foods
• Not stressful/restricting or overindulging• Consistency• Physical activity*
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3. Greenleaf, J., et al. (1969). Muscle glycogen and its significance for the water content of the body. Acta Physiologica Scandinavica Supplementum.
4. Kreitzman, S., et al. (1992). Glycogen storage: Illutions of easy weight loss, excessive weight regain, and distortions in estimations of body composition. The American Journal of Clinical Nutrition, 56, 292S-293S.
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starvation and low-calorie ketogenic and nonketogenic diets. The Journal of Clinical Investigation, 58(3), 722-730.8. Hill, J., et al. (1988). Effects of meal frequency on energy utilization in rats. American Journal of Physiology, 255, R616-R621.9. Wolfram, G., et al. (1987). Thermogenesis in humans after varying meal time frequency. Annals of Nutrition and Metabolism, 31(2), 88-97.10. Bellisle, F., et al. (1997). Meal frequency and energy balance. British Journal of Nutrition, 77, S57-S70.11. American College of Sports Medicine. (2005). Resource Manual for Guidelines for Exercise Testing and Prescription.12. McArdle, W., et al. (2010). Exercise physiology: Nutrition, energy, and human performance.13. Behnke, A., & Wilmore, J. (1974). Evaluation and regulation of body build and composition. 14. Kraemer WJ. General adaptations to resistance and endurance training. In: Baechle T, editor. Essentials of strength training and
conditioning. Champaign (IL): Human Kinetics, 1994: 127-5015. Forbes, G. (1991). Exercise and body composition. Journal of Applied Physiology, 70, 994-997.16. Wilmore, J. (1974. Alterations in strength, body composition, and anthropometric measurements consequent to a 10 week weight training
program. Medicine and Science in Sport and Exercise, 6, 133-138.17. Welle, S., et al. (1989). Stimulation of protein turnover by carbohydrate overfeeding in men. American Journal of Physiology, 257, E413-
E417. 18. Forbes, G., et al. (1986). Deliberate overfeeding in women and men: Energy cost and composition of weight gain. British Journal of
Nutrition, 56, 1-9.19. Fink, H., et al. (2009). Practical Applications in Sports Nutrition.