Transcript BONE HEALTH IN WOMEN

IN THE NAME OF GOD
BONE HEALTH IN FEMALE
ATHLETES
Dr. L.Hakemi
Internist
Sports Medicine Federation of IRAN
OSTEOPOROSIS
one of the most common metabolic disorders
and the most common metabolic bone disease.
.
Osteoporotic Fx
• a principal cause of disability and death.
• Approx. 1.5 million fragility fractures (after
trauma no greater than a fall from a
standing height) occur annually in the US,
and this number increases after 70s.
Factors:
nutrition
Physical activity
Chronic diseases
Medications
GENETIC
Exercise has positive effects on bone mass
Calcium supplements protect against bone loss in postmenopausal women
Reid, IR, Ames, RW, Evans, MC, et al, N Engl J Med 1993; 328:460.
Calcium supplementation decreases hip bone loss during the winter
Storm, D, Eslin, R, Porter, E, et al, J Clin Endocrinol Metab 1998; 83:3817.
recommendations
Daily calcium
• at least 1000 mg in premenopausal women and men
• 1500 mg in postmenopausal women who do not take
estrogen
• the total intake of calcium should not routinely exceed 2000
mg/day.
• Vit D
• 800 IU/day is for the elderly.
Estimation of calcium intake
• 300 mg for each glass of milk or yogurt or
30 ml of cheese.
• Calcium absorption from vegetables such
as spinach is less than dairy products.
• Calcium from dietary sources probably is
less likely to increase the risk of kidney
stones.
In an osteoporotic patient contact sports should be avoided
Recommendations
1.Aerobic exercise
2.Balance exercises
3.Strength exercises
4.Flexibility exercises
5.Weight bearing exercises
Osteoporosis prevention must be started from childhood
• Osteoporosis originates early in life and
bone mass development in childhood and
adolescents influences the risk for bone
fractures
• Daily physical activity in adolescence and
young adulthood is positively related to
bone mineral density in adulthood
• Risk of hip fracture in older females can be
reduced by nearly 20% if adolescent and
teenage girls engage in regular physical
activity
• The amount of exercise a girl gets at 12-18
years age is very important in the density and
strength of the proximal femur, and thus a crucial
factor in the prevention of hip fractures due to
osteoporosis in postmenopausal women
• Among 81 healthy white females exercise was
more important than dietary calcium in reaching
peak bone mineral density
• As the level of physical activity, fitness and lean
body mass increases, BMD also increase
Female Athlete Triad
• Eating disorders/
Disordered eating
• Amenorrhea/
oligomenorrhea
• Osteoporosis/
osteopenia
DURING HEAVY EXERCISE, THE
PULSATILE GNRH MAY DISAPPEAR AT
THE HYPOTHALAMIC LEVEL
Prevalence
30-60% of elite female athletes
• Highest in:
– Aesthetic
– Endurance
• Mostly cross country skiers
Lean habitus
High power/ weight
• Adolescents with anorexia nervosa are
often hypogonadal as well, and both
causes contribute to reduced bone mass
• Age at onset and duration of anorexia
correlate with bone mineral density
• Appropriately programmed exercise has salient effects
on the development of healthy bones. However, delayed
menarche may have adverse effects on the health of
their bones and also on other systems in their body.
• Heavy exercise together with a diet that is low in calories
puts the athlete at risk of developing delayed menarche.
Age at Menarche
Gymn/ Poland
15.1+/-0.9
Swim/ UK
13.3 +/-1.1
Gymn/ Switze
14.5+/-1.2
Tennis/ UK
13.2 +/- 1.4
Gymn/ Swed
14.5+/-1.4
Track/Poland
12.3+/- 1.1
Gymn/ UK
14.3 +/- 1.4
Track/ Hung
12.6
Gymn/ Hung
15.0 +/- 0.6
Row/ Poland
12.7 +/- 0.9
Gymn/ world
15.6 +/- 2.1
Skate/ US
14.2 +/- 0.5
Eliteballet/ US
15.4 +/- 1.9
Diving/ US
13.6 +/- 1.1
Soccer/ US
12.9 +/- 1.1
In 454 cases that were
passed menarche age
 mean of age at menarche:
158.2+/- 0.7 m. (13.18 yr)
HAKEMI, TORKAN, KABIR
• Earlier menarche was reported in :
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1-lower height (p<0.001)
2-lower age at beginning exercise (p=0.019)
3-lesser number of sisters (p=0.007)
4-lesser number of brothers (p=0.003)
5-higher percent body fat (p=0.037)
6-higher body mass index (p=0.002)
7-residing mountain side regions (p=0.001)
HAKEMI, TORKAN, KABIR
Does exercise affect height?
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NATURAL SELECTION
GH SECRETION
ENERGY REQUIREMENTS
MACRO AND MICRONUTRIENT
REQUIREMENTS
• AVOIDING APOPHYSIAL INJURIES
• AVOIDING TRIAD
• AVOIDING BANNED DRUGS
MALE
FEMALE
SPORT
HT
(CENTILE)
WT
(CENTILE)
SPORT
HT
(CENTILE)
WT
(CENTILE)
BASKETBA
LL
>=50
>=50
BASKETBAL
L
>=75
50-75
SOCCER
+/- 50
+/- 50
75
50-75
ICE
HOCKEY
+/- 50
50
VOLLEYBAL
L
SOCCER
50
50
DISTANCE
RUNS
+/- 50
=<50
DISTANCE
RUNS
>=50
<50
SPRINTS
>=50
>=50
SPRINTS
>=50
=<50
SWIMMING
50-90
50-75
SWIMMING
50-90
50-75
DIVING
<50
=<50
DIVING
=<50
50
GYMNASTI
CS
<25
<25
GYMNASTI
CS
=<10
10-50
TENNIS
+/-50
>=50
TENNIS
>50
+/-50
FIGURE
SKATING
10-25
10-25
FIGURE
SKATING
10-50
10-50
BALLET
<50
10-50
BALLET
=<50
10-50
Overuse injuries
• Common overuse injuries include stress
fractures, tendonitis, and bursitis.
• Female athletes are more susceptible
• Two apparent reasons for this:
• a lack of long-term preparation for
vigorous sports and
• not beginning sports training until growth
spurt (typically 11-13), a time when
musculoskeletal injury incidence is greater
Peak velocity of growth in
bone mineral content lags
nearly 1 year after peak
height spurt, thus during
this period the bones are
somewhat fragile and more
susceptible to injury
• Timing, duration and intensity of physical
activity determines whether a positive or
negative effect on bone mass density
• Excessive exercise may suppress
hypothalamic- gonadal axis, cause primary
or secondary amenorrhea and reduced
bone mineral density.