Int J Sports Med 2000; 21(7): 518-523
DOI: 10.1055/s-2000-7409
Orthopedics and Clinical Science
Georg Thieme Verlag Stuttgart · New York

Compressive and Shear ForceGenerated in the Lumbar Spine of Female Rowers

F.  L. Morris1 , R.  M. Smith2 , W.  R. Payne3 , M.  A. Galloway4 , J.  D. Wark1
  • 1 Department of Medicine, University of Melbourne, Melbourne, Australia
  • 2 Department of Biomechanics, Faculty of Health Sciences, University of Sydney, Australia
  • 3 School of Human Movement and Sports Science, University of Ballarat, Australia
  • 4 Elite Sport Unit, New South Wales Academy of Sport, Australia
Further Information

Publication History

Publication Date:
31 December 2000 (online)

Rowers have and accrue greater lumbar spine bone mineral density (BMD) associated with mechanical loading produced during rowing. The aim of this study was to estimate the mechanical loading generated at the lumbar spine (LS) that is apparently providing an osteogenic benefit. The cohort comprised 14 female rowers (average age: 19.7 yrs; height: 170.9 cm, weight: 59.5 kg) and 14 female matched controls (average age: 20.9 m yrs; height: 167.5 cm; weight: 58.1 kg). BMD was assessed using the Hologic QDR 2000+ bone densitometer, indicating higher lumbar spine BMD in the rowers compared to the control subjects (1069 ± 0.1 vs. 1027 ± 0.1 g/cm2). No significant difference existed for BMD at any other site. All rowers performed a six-minute simulated race on a Concept II rowing ergometer. Mechanical loading generated at the lumbar spine during this task was assessed using a two-dimensional model of the spine, enabling the calculation of the compressive and shear forces at L4/L5. The shear force was the joint reaction force perpendicular to the spine at the L4/L5 joint. Peak compressive and shear force at the lumbar spine of the rowers were 2694 ± 609 (N) and 660 ± 117 (N), respectively. Peak compressive force at the LS relative to body weight was 4.6 times body weight. The literature would suggest that forces of this magnitude, generated at the LS during maximal rowing, may be contributing to the site specific higher LS BMD found in the rowers.

References

Dr. Fiona L. Morris

School of Biomedical and Sport Science Edith Cowan University

100 Joondalup drive Joondalup Western Australia Australia, 6027

Phone: Phone:+ 618 (9400) 5012

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