Article Text

Download PDFPDF

Physiological factors associated with low bone mineral density in female endurance runners
  1. M Burrows1,
  2. A M Nevill2,
  3. S Bird2,
  4. D Simpson3
  1. 1University of East London, School of Health and Biosciences, Stratford Campus, Romford Road, London E15 4LZ
  2. 2University of Wolverhampton, School of Sport, Performing Arts, and Leisure, Gorway Road, Walsall, West Midlands WS1 3BD, UK
  3. 3Department of Nuclear Medicine, Kent and Canterbury Hospital, Canterbury, Kent CT1 3NG, UK
  1. Correspondence to:
 Dr Burrows, University of East London, School of Health and Biosciences, Stratford Campus, Romford Road, London E15 4LZ, UK;
 m.burrows{at}uel.ac.uk

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 osteoporosis.

  • osteoporosis
  • endurance running
  • female athlete triad
  • diet
  • lean body mass
View Full Text

Statistics from Altmetric.com

Footnotes

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.