The flashcards below were created by user efrain12 on FreezingBlue Flashcards.

  1. 4 dietary sources that affect bone health



    -vitamin D
  2. Stages of bone development) growth
    • The size of the bone is determined during its growth phase
    • *occurs in developing skeleton
  3. Stages of bone development) modeling
    • The shape of the bone is determined during this phase
    • *occurs in developing skeleton
  4. Stages of bone development) remodeling (3)
    • -Process of replacing existing bone
    • *turnover

    -maintains mineral homeostasis

    -occurs both in developing skeleton and adult bone
  5. Bone remodeling process) osteoclasts
    • erode the bone surface and form cavities in the bone
    • *resorption
  6. Bone remodeling process) Osteoblasts
    • Act at site of bone cavities to synthesize new bone matrix
    • *formation
  7. Bone remodeling process) when does bone loss occur?
    When resorption exceeds formation
  8. 3 factors that affect bone remodeling

    -nutrient status

  9. Factors that affect bone remodeling) hormones
    Estrogen, vitamin D, parathyroid hormone, calcitonin
  10. Factors that affect bone remodeling) nutrient status
    Calcium bioavailability
  11. Factors that affect bone remodeling) Exercise
    • Weight bearing or not?
    • *weight bearing exercise causes stress marks on the bone which leads to new formation of bone
  12. 2 types of bone

  13. Types of bone) trabecular (3)
    • -20% of skeleton
    • *faster turnover than cortical

    -found in axial skeleton, flat bones, ends of long bones

    -lower in density and strength than cortical
  14. Types of bone) cortical (3)
    • -80% of skeleton
    • *only 5% of surfaces in active remodeling at one time

    -found in long bones of body

    -more dense than trabecular
  15. When is the peak bone mass for females?
    90% reach peak at 16.9 yrs
  16. When is the peak bone mass for males?
    Most reach their peak between 20-29 years
  17. 5 things to know about bone loss?
    -increases with age

    -accelerated during periods of prolonged activity or bed rest

    -post menopause

    -poor calcium and or vitamin D intake

    -amenorrheic athletes
  18. 5 other exercise related functions of calciium
    -enzyme activation

    -nerve transmission

    -muscle contraction

    -hormone function

    -membrane transport
  19. 2 facts about intake requirements on calcium
    -calcium intakes are typically less in females than males

    -requirements increase with high sweat rates
  20. 2 facts about calcium
    • -largest component of the solid particles of bone
    • *99% of calcium in body is in bone

    -body prioritizes maintaining blood calcium levels over bone levels
  21. Food sources of calcium
    Milk products, spinach, kale, kidney beans, tofu
  22. Phosphorus) important roles related to exercise (4)
    -part of nucleic acids, proteins, ATP, and lipids

    -part of bone mineral composition

    -phosphorus salts act as buffers that maintain acid-base balance

    -important as electrolytes in fluid balance
  23. Phosphorus) 2 facts regarding intake
    -calcium and phosphorus absorption are coupled so that a low phosphorus absorption causes low calcium absorption

    -very high phosphorus intakes can possibly result in bone loss
  24. Phosphate loading- what occurs if an athlete consumes high does of phosphorus prior to competition?
    May increase VO2 max and anaerobic threshold
  25. Magnesium) 3 facts
    -Important in bone mineralization

    -holds calcium in tooth enamel

    -plays important role in substrate metabolism and energy production
  26. Magnesium) what roles does it play regarding postmenopausal women
    It reduces fracture risk and bone loss
  27. What is the primary role of vitamin D
    To maintain proper serum calcium concentration
  28. 5 functions of vitamin D
    -helps maintain skeletal calcium balance

    -promotes absorption of calcium

    -promotes bone resorption

    -maintains adequate calcium and phosphorus for bone formation by its action on the kidneys and intestines

    -allows proper functioning of parathyroid hormone to maintain serum calcium at proper levels.
  29. What are the consequences of excessive vitamin D intake?
    result in toxicity or decreased bone mass
  30. 2 sources of vitamin D
    -Synthesized in skin tissue upon exposure to UV light

    -milk, margarine, baked goods, grain products
  31. Effects of exercise on bone health) 2 positive effects exercise has on bone health
    -regular participation in moderate to vigorous weight bearing physical activity is related to a higher bone density

    -active people tend to have higher bone density values than do sedentary people
  32. Effects of exercise on bone health) one negative impact regarding this topic
    Females with altered menstrual function and males that participate in non-weight bearing activities (cycling) are at risk for low bone density
Card Set:
2014-03-13 16:25:50
Sports Nutrition

Bone health
Show Answers: