Weight Loss, Weight Gain and Weight Maintenance

1. Weight Loss, Weight Gain and Weight Maintenance

2. Energy Units • calorie • Basic energy/heat unit • The amount of heat necessary to raise temp of 1 gram of water 1° C. • Kilocalorie (kcal) • Basic food energy unit • The amount of heat necessary to raise temp of 1 kg water 1° C • 1 kcal = 1000 calories • Calorie is same as kcal

3. Body Fatness • Minimal Fat • Males: ~3% • Females: ~12% • Ideal Fatness • Varies with individual • Varies with type of athlete

4. Basic Energy Equation If Energy Consumed is = Energy Expended, then weight is stable If Energy Consumed is >Energy Expended, then weight is gained If Energy Consumed is < Energy Expended, then weight is lost

5. Energy Storage in the Body • Excess energy in any form is stored • Excess CHO is stored as fat • Excess Pro is stored as fat • Excess Fat is stored as fat • Must distinguish excess energy from energy necessary for muscular contaction • Liver glycogen • Muscle glycogen • Muscle triglycerides

6. Energy Stores in Normal, Sedentary Adults

8. 50 kcal Daily Energy Gain • 350 kcal per week (0.1 pounds) • 18,200 kcal per year (5.2 pounds) • 182,00 kcal per decade (52 pounds)

10. Food and Weight Loss • The most important factor is the total number of calories consumed • Carbohydrates and protein consumed in excess of the body’s need will result in the excess being stored as fat. • It is more efficient for the body to store fat as fat than to store carbos or protein as fat. • 95% of excess fat calories are stored as fat • 75-80% of excess carbo/protein is stored as fat

11. Glycemic Index (GI) The GI reflects the rate of digestion and absorption of CHO Blood glucose area after test food GI = X 100 Blood glucose area after reference food

12. Glycemic Index • Measure of how rapidly CHO is digested and becomes available in the blood • Highest value assigned to glucose (100) • The higher the value, the faster it gets into the blood • The higher the value, the greater the insulin response

14. Problem with Chronic Hyperinsulemia • Promotes fat storage • “wears out” the pancreas • Promotes Type II Diabetes

15. Characteristics of Fat That Make it Preferential to CHO as a Storage Substrate • More than 2X as much energy per gram • 1 gm fat = 9 kcals • 1 gm CHO = 4 kcals • Not hydrated when stored • For every gram of glycogen stored, 3 grams of water are stored. • Average person would have 50-75 additional pounds as water if fat were hydrated to the same extent as water.

18. Exercise and Weight Loss • Regular aerobic exercise may increase BMR • More calories can be expended doing aerobic exercise than any other kind • The harder you exercise and the longer you exercise, the more calories you expend.

19. Misconceptions about Exercise and Weight Loss • To loose fat from a certain area of the body, exercise that particular area • Exercising at a lower intensity will reduce fat more than exercising at a higher intensity

20. Tips for Effective Weight Loss • Weight loss is a long term project. There are no easy short cuts. • Reduce fat in your diet to less than 30% of total calories • Reduce total calories by no more than 25% of calories required to maintain weight • Increase caloric expenditure and REE with regular aerobic exercise???

22. Weight Gain • Adequate caloric intake • 2500-3500 kcal per pound of muscle • 1 pound of gain per week or 400-500 kcals per day • Adequate protein intake (0.8-2 g/kg) • Adequate stimulus of skeletal muscle • Adequate recovery for muscle • Adequate hormonal environment • Timing of protein intake • Supplements