|Title: ||Physiological factors associated with low bone mineral density in female endurance runners|
|Citation: ||British Journal of Sports Medicine, 37: 67–71|
|Publisher: ||BMJ Publishing|
|Issue Date: ||2003 |
|Additional Links: ||http://bjsm.bmj.com/cgi/content/abstract/37/1/67|
|Submitted date: ||2007-12|
|Abstract: ||Objective: To explore potential factors that could be associated with low bone mineral density (BMD)
in female endurance runners.
Methods: Fifty two female endurance runners (1500 m to marathon), aged 18–44 years, took part.
Body fat percentage, lumbar spine BMD, and femoral neck BMD were measured using the Hologic
QDR 4500w bone densitometer. Data on training, menstrual cycle status, osteoporosis, and health
related factors were obtained by questionnaire. Dietary variables were assessed from a prospective
seven day dietary record of macronutrients and micronutrients.
Results: The mean (SD) lumbar spine and femoral neck BMD were 1.11 (0.11) and 0.89 (0.12) g/cm2
respectively. A backward elimination regression analysis showed that age, body mass, body fat, distance
run, magnesium, and zinc intake were the variables significantly associated with BMD. Lumbar
spine BMD (g/cm2) = -1.90 + (0.0486 ´ age (years)) + (0.342 ´ log mass (kg)) - (0.000861 ´ age2
(years)) - (0.00128 ´ distance (km/week)), with an R2 = 30.1% (SEE = 0.089 (95% confidence interval
(CI) 0.05 to 0.23); p<0.001). Femoral neck BMD (g/cm2) = -2.51 - (0.00989 ´ age (years)) +
(0.720 ´ log mass (kg)) + (0.000951 ´ magnesium (mg/day)) -(0.0289 ´ zinc (mg/day)) - (0.00821
´ body fat (%)) - (0.00226 ´ distance (km/week)), with an R2 = 50.2% (SEE = 0.100 (95% CI 0.06
to 0.22); p<0.001). The negative association between skeletal BMD and distance run suggested that
participants who ran longer distances had a lower BMD of the lumbar spine and femoral neck. Further,
the results indicated a positive association between body mass and BMD, and a negative association
between body fat and BMD.
Conclusions: The results suggest a negative association between endurance running distance and
lumbar spine and femoral neck BMD, with a positive association between body mass and femoral neck
and lumbar spine BMD. However, longitudinal studies are required to assess directly the effect of
endurance running and body mass on BMD, and to see if the addition of alternative exercise that
would increase lean body mass would have a positive effect on BMD and therefore help to prevent
|Keywords: ||Bone mineral density|
|Appears in Collections: ||Sport, Exercise and Health Research Group|
Exercise and Health
Learning and Teaching in Sport, Exercise and Performance
|Files in This Item:|
|Nevill bjsm 2003.pdf||314Kb||Adobe PDF|
All Items in WIRE are protected by copyright, with all rights reserved, unless otherwise indicated.