The influence of weight-bearing impact exercise and muscle strength on bone properties in healthy humans: sex- and age-specific effects

负重冲击运动和肌肉力量对健康人类骨骼特性的影响：性别和年龄特异性影响

• 批准号: RGPIN-2020-04791
• 负责人: Gibbs, Jenna
• 金额: $ 1.75万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=757849
• 关键词: influence; weight; bearing; impact; exercise

Exercise and muscle strength play a critical role in developing bone strength, providing mechanical protection, and preserving skeletal tissue. Bone remodeling is influenced by mechanical forces applied to bone, including ground reaction forces and internal muscle forces. Weight-bearing impact exercise, involving moderate-to-high magnitude loads (=2-4 times body weight) and multidirectional movement patterns, is considered the most effective strategy for inducing changes in bone material and structural properties. Muscle forces can influence bone strength by applying strains to stimulate bone formation, and therefore contribute to the regulation of bone strength (known as the functional muscle-bone unit theory). Muscle-derived growth factors may also stimulate bone formation independent of mechanical loading, further demonstrating evidence of a muscle-bone relationship. Despite substantial evidence in support of a positive association between muscle mass and strength and surrogates of bone strength, we have limited understanding of which mechanical and biochemical muscle-related factors explain the most variability in true estimates of bone strength. As well, the relationship between muscle and bone size and strength may differ between sexes and change significantly with age, yet we do not know how these sex- and age-related differences impact the capacity of bone to respond to anabolic stimuli (e.g., exercise). Therefore, the purpose of this proposal is to examine the influence of weight-bearing impact exercise and muscle strength on bone properties in healthy individuals and to determine whether their effects differ between sexes and with age. The goals of the proposed research program are to examine the sex differences in the muscle-bone regulatory mechanism as well as compare its determinants in younger and older adults. We will also conduct a pilot randomized study comparing a 12-month resistance training plus high-impact loading intervention versus resistance training alone and an attentional control group. These studies will provide novel insight into the independent and interacting roles of weight-bearing impact exercise and muscle-generating loading on bone strength, geometry, and structure in humans. Combining specialized measures to quantify bone material and structural properties with assessments of mechanical and biochemical muscle factors, we aim to provide new evidence on the role of muscle in governing the regulation of bone metabolism and the downstream effects on bone strength. The results from these studies will enhance our fundamental understanding of bone responses to different stressors of daily life and exercise in men and women across the lifespan.

运动和肌肉力量在发展骨骼强度，提供机械保护和保存骨骼组织方面起着至关重要的作用。骨重塑受到施加到骨骼的机械力的影响，包括地面反作用力和内部肌肉力。重量撞击运动涉及中度至高度载荷（= 2-4倍体重）和多向运动模式，被认为是诱导骨骼材料和结构特性变化的最有效策略。肌肉力可以通过施加菌株刺激骨形成来影响骨骼强度，因此有助于调节骨强度（称为功能性肌肉骨单位理论）。肌肉衍生的生长因子也可能刺激与机械负荷无关的骨形成，进一步证明了肌肉骨关系的证据。尽管有大量证据支持肌肉质量与力量与骨骼强度的替代物之间的正相关，但我们对哪些机械和生化肌肉相关的因素的理解有限，可以解释骨强度的真实估计值最大的可变性。同样，肌肉与骨骼大小和力量之间的关系可能会随着年龄的增长而显着变化，但是我们不知道这些与性别相关的差异如何影响骨骼对合成代谢刺激反应的能力（例如运动）。 因此，该提案的目的是检查体重撞击运动和肌肉力量对健康个体骨骼特性的影响，并确定其影响在性别和年龄之间是否有所不同。拟议的研究计划的目标是检查肌肉骨调节机制的性别差异，并比较其在年轻和老年人中的决定因素。我们还将进行一项试验随机研究，以比较12个月的电阻训练以及单独的电阻训练以及一个注意力控制组。这些研究将提供对体重撞击运动的独立和相互作用的新见解，以及人类骨骼强度，几何形状和结构的肌肉产生负荷。将专门的措施与机械和生化肌肉因素的评估相结合，以量化骨骼物质和结构特性，我们旨在提供有关肌肉在管理骨代谢调节和对骨强度的下游影响方面作用的新证据。这些研究的结果将增强我们对整个生命周期中男性和女性对不同压力的骨头反应的基本理解。