Function of the Axial Musculoskeletal System in Locomotion and Ventilation

9807534携带者剧烈运动需要更高的新陈代谢速度。因此，对于一种动物来说，要维持快速运动，它必须在跑步时呼吸。尽管人类认为运动中的呼吸是理所当然的，但越来越多的证据表明，在陆地脊椎动物中，同时奔跑和呼吸的能力是一种衍生条件。对鱼类和两栖动物的分析清楚地表明，腹部和胸部肌肉最初的功能是运动，而不是肺通风。这一点的重要性在蜥蜴身上是显而易见的，因为在蜥蜴中，产生通风的肌肉也在运动中发挥作用。在这些蜥蜴中，轴肌的运动功能超过了它们的呼吸功能。因此，在一些物种中，躯干肌肉的运动行为干扰了呼吸，以至于随着速度的增加，肺通气量和耗氧量都会下降。同样，在狗身上，轴向肌肉的运动功能似乎主导着这些肌肉的通风功能。当小跑的狗将它们的呼吸从运动周期中分离出来时，除了一到两块躯干肌肉的活动之外，所有的躯干肌肉的活动都保持在大步周期。这表明，四足动物要么不能同时奔跑和呼吸，要么它们的通风必须以某种方式与它们的运动相结合。这项研究旨在通过研究轴性肌肉-骨骼系统在跑步和呼吸中所起的作用，增加我们对运动和呼吸系统之间的机械联系的理解。它有两个目标。首先，卡里尔博士将使用肌电图术和运动力操纵来测试蜥蜴和哺乳动物的轴部肌肉运动功能的具体假设。其次，通过比较呼吸与运动周期耦合和不耦合时肌肉活动的强度，PI将确定运动-呼吸耦合是否减少哺乳动物奔跑和呼吸之间的冲突。这项研究将有助于我们理解在面对运动产生的相互冲突的需求时，氧级联是如何保持的；它将有助于澄清蜥蜴和哺乳动物之间的差异，这可能有助于解释奔跑蜥蜴对无氧代谢的依赖，以及哺乳动物维持有氧剧烈运动的能力。

9807534 Carrier Vigorous activity requires elevated rates of metabolism. Thus, for an animal to sustain rapid locomotion, it must breathe as it runs. Although humans take breathing during locomotion for granted, there is increasing evidence that the ability to run and breathe at the same time is a derived condition among terrestrial vertebrates. analysis of fishes and amphibians clearly shows that the original function of the muscles of the abdomen and thorax was locomotion rather than lung ventilation. The significance of this is apparent in lizards in which the muscles that produce ventilation also have a role in locomotion. In these lizards, the locomotor function of the axial muscles predominates over their ventilatory function. Consequently, in some species, the locomotor actions of the trunk muscles interfere with breathing to such an extent that and both lung ventilation and oxygen consumption decline as speed increases. Similarly, in dogs, the locomotor function of the axial muscles appears to be dominate over the ventilatory function of these muscles. When trotting dogs uncouple their breathing from the locomotor cycle, activity of all but one or two of the trunk muscles stays locked to the stride cycle. This suggests that tetrapods will either be unable to run and breathe at the same time, or their ventilation must in some way be integrated with their locomotion. The research described in this proposal is intended to increase our understanding of the mechanical linkage between the locomotor and ventilatory systems by investigating the role the axial muscle-skeletal system plays in running and breathing. It has two goals. First Dr. Carrier will use electromyography and manipulation of locomotor forces to test specific hypotheses of locomotor function for the axial muscles in both lizards and mammals. Second, by comparing the intensity of muscle activity when ventilation is coupled versus not coupled to the locomotor cycle, the PI will determine whether locomotor-venti latory coupling decreases the conflict between running and breathing in mammals. This study will contribute to our understanding of the ways in which the oxygen cascade is maintained in the face of conflicting demands resulting from locomotion; and it will help clarify differences between lizards and mammals which may help explain the reliance of running lizards on anaerobic metabolism and the ability of mammals to sustain vigorous locomotion aerobically.