Sports Nutrition

53 flashcards · Other · by Myra Tall

1. What are macronutrients?

   refer to Carbohydrates, proteins, and fats which are the primary building blocks your diet. They are consumed in large amounts, which provide you body with energy.

2. what is a carbohydrate?

   The combination of carbon and water

3. What is the most basic general structure of all carbohydrates?

   CxH2xOx

4. What are monosaccharides?

   Simple sugars or carbs, made from one sugar unit.

5. What are the three main types of monosaccharides?

   glucose, fructose, and galactose

6. Glucose

   The most useful form in animals. Forms the bulk of our carbohydrate stores.

7. Why is the level of glucose in the blood very important?

   It the main energy source for the brain, so when it runs low, the brain becomes dysfunctional.

8. What is the main determinant of fatigue during long-term endurance events?

   The depletion of glycogen/glucose stores.

9. Term phrases " bonking" or "hitting the wall" describes what?

   The sudden loss of speed when glucose stores run out.

10. Excess carbs are converted into what?

    Fat

11. Fructose

    Fruit sugar; it is also the sweetest sugar.

12. When taken during exercise, fructose does not enhance blood glucose and can cause GI distress. Why is that?

    extra processing is needed to make it available as energy. Fruit also contains fiber which is not easily digestible for the body.

13. Galactose

    formed by animals as part of lactose

14. Mannose and Xylose

    wood sugar; occurs in plants as large complexes which are almost indigestible.

15. Deoxyribose

    forms the sugar backbone of DNA

16. Disaccharides

    formed by 2 chemically boned monosaccharides.

17. What are the three main types of disaccharides?

    lactose, maltose, and sucrose

18. Lactose

    found in large amounts of diary products. It is broken down in the small intestine with the aid of lactase.

19. The lack of the enzyme lactase causes what?

    lactose intolerance

20. what two sugars form lactose?

    glucose + galactose

21. Maltose

    Usually formed from the breakdown of starch. It is broken down with the aid of maltase.

22. What two sugars form maltase?

    Glucose + Glucose

23. Sucrose

    Table sugar. broken down with the aid of sucrase.

24. Trehalose

    Mushroom sugar; often added to foods (gum, jelly) to change consistency.

25. Sucralose

    an artifical sweetner with 600x the sweetness of sucrose. Used to make foods sweeter with adding as many calories (e.g. splenda)

26. Oligosaccharides

    3-10 linked monosaccharides. FOund in products such as beans.

27. True/False: Oligosaccharides have certain chemical bonds, so they are largely indigestible

    True; but certain bacteria in the intestines can break them down, producing ordorous gases in the process.

28. polysaccharides

    Complex carbs; longs chains of monosacchaides.

29. Starch

    polysaccharide; the storage form of glucose in plants.

30. What are the 2 forms of starch?

    amylopectin, and amylose

31. Amylopectin

    contains branch points and is more digestible due to a greater exposure of chemical bonds to digestive enzymes. found in fruits

32. Amylose

    straight chains of glucose. Founds mostly in breads, crackers Etc. Not as easily digested and absorbed as amylopectin.

33. Which is better for diabetics: amylopectin or amylose?

    amylose

34. Fiber

    Strictly a plant material, makes up many of the structures of plants including cell walls. Many different forms, but two basic forms

35. Water Soluble Fiber

    Digestible and provide some nutritive value as well as some health effects.

36. Water Insoluble Fiber

    Indigestible and include cellulose (plant cell walls) and chitin (found in shells of shellfish and insects), both indigestible

37. T/F: Soluble fiber lowers cholesterol?

    True; specifically LDL

38. Which type of cholesterol is bad and which is good?

    LDL (bad); HDL (good)

39. Scraping Action

    Insoluble fiber (dietary fiber) is not digested and therefore can scrape the walls of the intestines, reducing the chances of colorectal cancer (3rd leading cancer in men – 28,000 per year)

40. Glycogen

    animal starch

41. Recommended intake of CHO

    60% of total calories; high fiber, unrefined carbohydrates are the best

42. Recommended fiber intake

    20-40g/ day; Females (~21g) Males (~38g)

43. What is Glycemic Index?

    How much a food elevates the blood glucose levels.

44. T/F: high glycemic foods enter the bloodstream rapidly and can trigger large insulin releases, which may contribute over time to diabetes and weight gain

    True

46. T/F: Glucose is the body's most usable fuel

    True

47. At rest and during low intensity exercise, what is the main source of energy being used?

    fat (from the blood).

48. As exercise intensity increases, the body increasingly relies on ___________ as the primary energy source?

    Glucose, from both the blood and from stored glucose in the muscle.

49. Why are Type II fibers activated at high intensities?

    Because they are largely anaerobic, they almost exclusively use glucose as an energy source.

50. Using glucose as an energy source results in more ATP with less oxygen. Why is this good?

    This is good since O2 is less abundant in the body at high intensities.

51. During exercise, lactate in the blood does what?

    slows down the release of fatty acids from the fat stores.

52. During exercise, when does protein loss occur?

    When glycogen is depleted, blood glucose levels fall, and byproducts of fat metabolism increase. To keep blood glucose high enough for survival, protein is converted into glucose (gluconeogenesis). This removes protein from body structures (i.e. muscle).

53. What does the phrase “fats burn in a carbohydrate flame” mean?

    you need carbs to get it going, you not just going to burn fat straight away. Without carbs, fat breakdown only produces ketone bodies and acidic blood.