Guillemant J, Accarie C, Peres G, Guillemant S
Faculté de Médecine Pitié-Salpêtrière, Service de Biochimie, Paris, France.
Calcif Tissue Int. 2004 May;74(5):407-14. doi: 10.1007/s00223-003-0070-0. Epub 2004 Jan 23.
Although sport and physical activity are generally considered as positive factors for bone metabolism some endurance trainings such as running and bicycling have few or no beneficial or even deleterious effects on bone mineral density. The present study was designed to investigate the acute effect of an intensive endurance cycling exercise on biochemical bone markers. Furthermore, the effect of the oral intake of 1 g calcium load, by drinking high-calcium mineral water, just prior to and during the exercise was checked. Twelve well-trained elite male triathletes aged 23-37 years were explored. The serum concentrations of calcium, phosphate, PTH, bone alkaline phosphatase (BALP) and C-terminal cross-linking telopeptide of type 1 collagen (CTX) were measured before, during and after a 60 min 80% VO2max cycle ergometer exercise. Since cycling exercise was accompanied by a reduction in plasma volume the total amount of biochemical bone markers was calculated. When the exercise was performed without calcium load both serum concentrations and total amount of CTX began to increase progressively 30 min after the start of the exercise and were still significantly elevated, by 45-50%, 2h after the end of the exercise. Ingestion of high-calcium mineral water completely suppressed the CTX response. By contrast serum concentrations and total amount of BALP fluctuated and showed no significant difference with or without calcium load. The present study demonstrates that the burst of osteoclastic activity acutely induced by an endurance cycling exercise can be suppressed by the previous intake of a calcium load afforded by drinking high-calcium mineral water.
尽管运动和体育活动通常被视为对骨代谢的积极因素，但一些耐力训练，如跑步和骑自行车，对骨矿物质密度几乎没有益处，甚至有有害影响。本研究旨在调查高强度耐力自行车运动对生化骨标志物的急性影响。此外，还检查了在运动前和运动期间通过饮用高钙矿泉水口服1克钙负荷的效果。研究了12名年龄在23 - 37岁之间训练有素的精英男性铁人三项运动员。在进行60分钟80%最大摄氧量的自行车测力计运动前、运动期间和运动后，测量血清钙、磷、甲状旁腺激素（PTH）、骨碱性磷酸酶（BALP）和I型胶原C端交联肽（CTX）的浓度。由于自行车运动伴随着血浆量的减少，因此计算了生化骨标志物的总量。在无钙负荷情况下进行运动时，CTX的血清浓度和总量在运动开始后30分钟开始逐渐升高，在运动结束后2小时仍显著升高45 - 50%。摄入高钙矿泉水完全抑制了CTX的反应。相比之下，BALP的血清浓度和总量波动，在有或无钙负荷情况下无显著差异。本研究表明，饮用高钙矿泉水提供的钙负荷预先摄入可抑制耐力自行车运动急性诱导的破骨细胞活性爆发。
