Nutrition II

1. Nutrition II

2. Nutrients Macronutrients Micronutrients Carbohydrate Vitamins Fat Minerals Protein H2O

3. Micronutrients and H2O • vitamins and minerals • found in variety of foods • balanced diet  no supplementation (Ca++)

4. Vitamins • Accessory nutrients (C,H,O) • Supplied thru diet (except D) • Manufactured during photosynthesis

5. Types of Vitamins • Lipid soluble - A, D, E, and K • Water soluble - C - B: B1, B2, B6, B12, niacin, folic acid

6. Lipid Soluble • Should not be consumed in excess • E.g. kidney damage 20 excess D

7. Water Soluble • Generally not stored • Excess is voided

8. Role of Vitamins • Links & regulators in energy releasing reactions • Control tissue synthesis

9. Supplementation Supplementation Proper Diet Repeated Use However?

10. Supplementation • Exceptions: - C - B – folic acid - B1 and B6 (some athletes) - B12 in vegetarians

11. Antioxidant Role • Free radicals - highly chemically reactive molecules/fragments • Produced in body: - O2-, H202, OH- • Produced in environment: - smoke, pollutants, medications

12. Antioxidant Role •  free radicals   oxidative stress/cellular damage •  oxidation of LDL   atherosclerosis • Oxidataive stress  cell deterioration, advanced aging, CA, DM, CAD

13. Antioxidant Vitamins • A (& precursor -carotene), C , E • Protect plasma membrane • -carotene & C   CA • E & -carotene   CAD, blood clots

14. Recent Research •  roundworm life by 50% • synthetic drugs that mimic: • superoxide dismutase • catalase • persist longer than vitamins

15. Vitamins and Exercise • B-complex – coenzymes for CHO, lipid, & protein catabolism  energy • Contribute to Hb synthesis (RBC)

16. Megavitamins • 10-1000x RDA

17. Minerals • Elements • Constituents of enzymes, hormones, vitamins • Combine w/ other chemicals (calcium phosphate in bone, heme blood) • Critical for certain processes (muscle contraction)

18. Minerals • Naturally occurring • Supplementation unnecessary (except Ca, Fe) • Excess can be toxic

19. Roles of Minerals Structure (bones/teeth) Function: - heart rhythm - muscle contraction - neural conductivity - acid-base balance

20. Roles of Minerals Regulation • Cell metabolism (enzymes/hormones) • Balance catabolism/metabolism • electrolytes

21. Calcium • Osteoporosis • : - less bone density to start - reduced intake teenage years -  activity -  estrogen / menopause • Other factors: smoking, alcohol abuse

22. Prevention • Ca++ supplementation • Vitamin D availability • Estrogen therapy • W/b activities (consistent) • Avoid excessive meat, salt, coffee, alcohol

23. Prevention • 20 amenorrhea   estrogen

24. Phosporus • Provides rigidity to bones & teeth • Essential to ATP, CP • Combines w/ lipids  plasma membrane • Buffer acids produced 20 heavy exercise

25. Magnesium Involved in: • anabolism of serum glucose  liver/muscle glycogen • catabolism of glucose, fatty acids, AA • anabolism of lipids & proteins • nerve conduction and muscle action

26. Iron • Found in: - hemoglobin - myoglobin - cytochromes

27. Iron-deficiency anemia •  hemoglobin conc. • Sluggishness • Loss of appetite • Reduced capacity for exercise • Common in 

28. Iron-deficiency anemia in Females • Pregnancy • Menstruation • Vegetarian diet - animal Fe more readily absorbed

29. Iron RDA

30. Exercise-Induced Anemia? • Loss of iron thru: - Perspiration - Urine 20 RBC destruction &  temp. - Spleen activity - Mechanical RBC destruction • Probably minimal

31. Supplementation? • Hematological work-up • Accumulate to toxic level and contribute to: • Liver disease • DM • Heart damage / CAD • Joint damage

32. Electrolytes • Na+ - blood plasma/extracellular • Cl- - blood plasma/extracellular • K++ - chief intracellular

33. Na+ and Cl- • Modulate fluid exchange • Regulate exchange of nutrients and wastes between cell and external medium

34. Na+ and K++ • Establish electrical gradient across cell membranes for: • Nerve impulses • Muscle contraction • Gland function

35. Na+ induced HTN • 1/3 of individuals w/ HTN • Typical diet exceeds RDA by 10x • Not always the problem

36. Minerals & Exercise • Excessive loss  • Impair heat tolerance & performance  • Cramps • Exhaustion • Heat stroke

37. Supplementation Minerals & Exercise Good diet  Glass of OJ  replaces Ca, K, Mg lost in 3 L of perspiration

38. Water • 40 – 60% of body mass • 65 – 75% of muscle • 50% of body fat

39. Water • 62% extracellular • 38% intracellular

40. Functions of Water • Transport and reactive medium - diffusion of gases - transportation of nutrients, gases, & wastes • Heat-stabilizing • Lubricates joints • Structure & form

41. Water Regulation

42. Water Regulation in Hot Weather during Exercise

43. Water and Exercise • 100% relative humidity - evaporation impossible - loss of cooling mechanism • No humidity - optimum cooling - excessive fluid loss   plasma volume  circulatory strain

44. Assessing Fluid Loss • Accurate body weight pre- and post-exercise • 1 lb. BW = 450 mL (15 oz.) dehydration

45. Hyponatremia • Water intoxication 20: • Loss of electrolytes (Na+) • Large ingestion of water

46. Hyponatremia • Dilution of extracellular Na+ • Headache, confusion, malaise, nausea, cramping, coma, pulmonary edema, death

47. Hyponatremia • Usually during prolonged exercise • Do not consume > 1 L / hr. • Include some Na+ • Include glucose  facilitate glucose-sodium transport