Home > Journals > The Journal of Sports Medicine and Physical Fitness > Past Issues > The Journal of Sports Medicine and Physical Fitness 2012 October;52(5) > The Journal of Sports Medicine and Physical Fitness 2012 October;52(5):489-500


A Journal on Applied Physiology, Biomechanics, Preventive Medicine,
Sports Medicine and Traumatology, Sports Psychology

Indexed/Abstracted in: Chemical Abstracts, CINAHL, Current Contents/Clinical Medicine, EMBASE, PubMed/MEDLINE, Science Citation Index Expanded (SciSearch), Scopus
Impact Factor 1,111




The Journal of Sports Medicine and Physical Fitness 2012 October;52(5):489-500

language: English

BMD in elite female triathletes is related to isokinetic peak torque without any association to sex hormone concentrations

Wulff Helge E. 1, Melin A. 2, Waaddegaard M. 3, Kanstrup I.-L. 4

1 Department of Exercise and Sport Sciences, University of Copenhagen, Copenhagen, Denmark;
2 Team Danmarks Testcenter, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark;
3 Psychotherapeutic Center Stolpegaard, Eating Disorders Clinic, Copenhagen, Denmark;
4 Herlev Hospital, Department of Clinical Physiology and Nuclear Medicine, University of Copenhagen, Copenhagen, Denmark


AIM: Female endurance athletes suffering from low energy availability and reproductive hormonal disorders are at risk of low BMD. Muscle forces acting on bone may have a reverse itespecific effect. Therefore we wanted to test how BMD in female elite triathletes was associated to isokinetic peak torque (IPT) and reproductive hormone concentrations (RHC). A possible effect of oral contraceptives (OCON’s) is taken into consideration.
METHODS: Eight female elite triathletes (training 8-24 hrs/wk) and seven sedentary controls, age 21-37 years, participated. Total body and regional BMD (g.cm-2) were measured by DXA. IPT were measured during knee extension, and trunk extension and flexion (Nm). Serum RHC and biochemical bone markers were evaluated. Energy balance was estimated from 7-days training-and weighed food records.
RESULTS: Despite a high training volume, BMD in triathletes was not higher than in controls. In triathletes trunk flexion IPT, but not RHC, was a strong predictor of BMD in both total body and femur (0.70CONCLUSION: The association between trunk flexion IPT and BMD in triathletes supports the theory that muscle forces are important osteogenic factors. The findings of no correlation between RHC and BMD, but a tendency to a negative effect of low RHC only in OCON-controls, might indicate that in female athletes muscle forces acting on bone potentially counteract a negative effect of reproductive hormonal disorders on BMD.

top of page