Beeinflussung der Knochenqualität durch extreme körperliche Belastung

Abstract

The treatment of osteoporosis is still controversial. Rehabilitation programs which stress strengthening exercises as well as impact loading activities increase the bone mass. On the other side activity level early in life has not been proven to correlate with increased bone mineral content later in life. Little is known on the influence of high performance sports on the bone density especially in athletes with high demands on weight bearing of the spine. In (n = 40) internationally top ranked high performance athletes of different disciplines (n = 28 weight-lifters, n = 6 sports-boxers and n = 6 bicycle-racers) bone density measurements of the lumbar spine and the left hip were performed. The measurements were carried out by dual-photonabsorptiometry (DEXA; QDR 2000, Siemens) and evaluated by an interactive software-programme (Hologic Inc.). The results were compared to the measurements of 21 age-matched male control individuals. In the high performance weight lifters there was an increase of bone density compared to the control individuals of 23% in the Ward's triangle (p < 0.01). The sports-boxers had an increase up to 17% (lumbar spine), 9% (hip) and 7% (Wards' triangle). In the third athletes group (Tour de France-bikers) BMD was decreased 10% in the lumbar spine, 14% in the hip and 17% in the Wards' triangle. Our results show that training programs stressing axial loads of the skeletal system may lead to an increase of BMD in the spine and the hip of young individuals. Other authors findings, that the BMD of endurance athletes may decrease, is confirmed. Nevertheless the bikers BMD-loss of 10 to 17% was surprisingly high.

Boxing Practitioners Physiology Review: 2. Systemic Responses and Adaptations

“…The bone mineral density (BMD) of the boxers' lumbar spine has been found greater than that of the controls by 17% on the AP view (0.174 g•cm −2 ) and by 19% on the lateral view (0.174 g•cm −2 ) [46], as signaled in Table 5 and Figure 3. The boxers have shown an increase in hip BMD up to 9% and an increase in Ward's triangle BMD up to 7% [45], as also signaled in Table 5 and Figure 3.…”

“…That the increased hip BMD can be mediated by longitudinal weight bearing on the skeleton [19], has also been illustrated by the results of one of the studies here concerned [45]: there has been BMD increase in the boxers' hip (9%). The study has also signaled BMD increase in the Ward's triangle (7%) and in the lumbar spine (17%).…”

“…The control of bone mass is localized, and mechanical strain and its effect on bone can be very different from one part of the skeleton to another [19]. That is reflected in differences of percentage increases according to the concerned part of the skeleton, as shown by the results of the study here concerned [45]. Open Journal of Molecular and Integrative Physiology Effect of load-bearing is also expressed when the dominant arm is compared with the other arm, as suggested by the results obtained from examination of male veteran tennis players [19].…”