Laboratory of Applied Sport Physiology, School of Applied Sciences, University of Campinas, Pedro Zaccaria Street, 1.300, Jardim Santa Luíza, Limeira, SP, 13484-350, Brazil.
Laboratory of Endocrine Physiology and Physical Exercise, Department of Physiological Sciences, Federal University of São Carlos, São Carlos, SP, Brazil.
Sci Rep. 2021 Mar 19;11(1):6414. doi: 10.1038/s41598-021-85585-9.
High-intensity interval training (HIIT) is of scientific interest due its role in improving physical fitness, but the effects of HIIT on bone health need be carefully explored. Further, it is necessary to know whether HIIT effects on bone health are dependent on the physical activity levels. This may be experimentally tested since we have built a large cage (LC) that allows animals to move freely, promoting an increase of spontaneous physical activity (SPA) in comparison to a small cage (SC). Thus, we examined the effects of HIIT on biophysical, biomechanical and biochemical parameters of bone tissue of C57BL/6J mice living in cages of two different sizes: small (SC) or large (LC) cages with 1320 cm and 4800 cm floor space, respectively. Male mice were subdivided into two groups within each housing type: Control (C) and Trained (T). At the end of the interventions, all mice were euthanized to extract the femur bone for biophysical, biomechanical and biochemical analyses. Based a significant interaction from two-way ANOVA, trained mice kept in large cage (but not for trained mice housed in SC) exhibited a reduction of tenacity and displacement at failure in bone. This suggests that long-term HIIT program, in addition with a more active lifestyle correlates with exerts negative effects on the bone of healthy mice. A caution must also be raised about the excessive adoption of physical training, at least regarding bone tissue. On the other hand, increased calcium was found in femur of mice housed in LC. In line with this, LC-C mice were more active (i.e. SPA) than other groups. This implies that an active lifestyle without long-term high intensity physical training seems to play a role in promoting benefits to bone tissue. Our data provides new insights for treatment of osteo-health related disorders.
高强度间歇训练（HIIT）因其在改善身体健康方面的作用而引起了科学界的兴趣，但 HIIT 对骨骼健康的影响需要仔细探索。此外，有必要了解 HIIT 对骨骼健康的影响是否取决于身体活动水平。由于我们建造了一个大型笼子（LC），可以让动物自由移动，与小笼子（SC）相比，促进了自发性身体活动（SPA）的增加，因此可以进行实验测试。因此，我们研究了生活在两种不同大小笼子中的 C57BL/6J 小鼠的 HIIT 对骨组织的生物物理、生物力学和生物化学参数的影响：小（SC）或大（LC）笼，分别具有 1320cm 和 4800cm 的底面积。雄性小鼠在每个笼中分为两组：对照组（C）和训练组（T）。在干预结束时，所有小鼠均被安乐死，以提取股骨进行生物物理、生物力学和生物化学分析。基于双向方差分析的显著交互作用，在大笼中接受训练的小鼠（但不在 SC 中接受训练的小鼠）表现出骨韧性和破坏时位移的降低。这表明，长期 HIIT 计划，加上更积极的生活方式，与健康小鼠的骨骼负相关。还必须对过度采用身体训练（至少对骨骼组织而言）提出警告。另一方面，LC 饲养的小鼠的股骨中发现了更多的钙。与此一致的是，LC-C 小鼠比其他组更活跃（即 SPA）。这意味着，没有长期高强度体力训练的积极生活方式似乎在促进骨骼组织受益方面发挥作用。我们的数据为治疗与骨健康相关的疾病提供了新的见解。
