Bone quality in the lumbar spine in high-performance athletes.

Little is known about the influence of high-performance training on the bone quality of the lumbar spine, in particular, the effects on bone mineral density (BMD) in athletes with high weight-bearing demands on the spine. Measurements were therefore performed in internationally top-ranked high-performance athletes of different disciplines (weight lifters, boxers, and endurance-cyclists). The measurements were carried out by dual-energy X-ray absorptiometry, and the results compared with the measurements of 21 age-matched male controls. The BMD of the high-performance weight lifters was greater than that of the controls by 24% (0.252 g/cm2) on the AP view by 23% (0.200 g/cm2) on the lateral view (P < 0.01), while difference in BMD between the boxers and the controls was +17% (0.174 g/cm2) on the AP view and +19% (0.174 g/cm2) on the lateral view. The BMD of the lumbar spine in all endurance cyclists was lower than that in the controls (AP view -10%, 0.105 g/cm2; lateral view -8%, 0.067 g/cm2; P > 0.05). The results show that training program stressing axial loads of the skeleton may lead to a significant increase of BMD in the lumbar spine of young individuals. Other authors' findings that the BMD of endurance athletes may decrease are confirmed. Nevertheless the 10% BMD loss of cyclists was surprisingly high.