尽管增加了新陈代谢率和乳酸稳定状态,但仍保持了燃料混合
在PubMed上查看摘要
概括
此摘要是机器生成的。较高的循环节奏降低了碳水化合物氧化 (CHO) 和总效率 (GE),但增加了血液乳酸度 (BLC). 精英骑自行车者可以从更高的步数中获益,以节省CHO储量,提高性能.
科学领域
- 运动生理学
- 运动科学
- 代谢研究
背景情况
- 了解长时间运动中的基质利用对于优化运动表现至关重要.
- 循环节奏是影响新陈代谢反应和效率的关键变量.
- 之前的研究对节奏对碳水化合物氧化和血中乳酸水平的影响产生了不同的结果.
研究的目的
- 研究循环节奏 (60比100rpm) 对血液乳酸度 (BLC),碳水化合物氧化 (CHO) 和总效率 (GE) 的影响.
- 检查运动强度和预负荷在长时间循环过程中如何影响这些代谢参数.
- 为耐力运动员提供最佳节奏策略的见解.
主要方法
- 十一名男性三项运动员进行了增量测试,以确定峰值功率 (Pike).
- 长时间循环测试 (60分钟) 在不同强度 (40%,60%,70%峰值) 和节奏 (60和100rpm) 进行.
- 测量包括BLC,氧气吸收,二氧化碳产量,并计算了GE,CHO和用于CHO的氧气吸收分数 (relCHO).
主要成果
- 更高的节奏 (100rpm) 导致更低的GE和增加的BLC,氧气吸收和CHO.
- 碳水化合物氧化 (CHO) 和relCHO在冷却阶段与热化相比较低,不论BLC.
- 增加运动强度导致了更高的relCHO,但节奏并没有显著影响relCHO.
结论
- 较高的循环节奏可能会在给定的代谢需求和BLC下促进较低的碳水化合物利用,特别是在较低的强度下.
- 预负荷可能会降低CHO和relCHO,这可能与pyruvate和乳酸可用性无关.
- 对于精英骑自行车者来说,在更高的速度下保持稳定或改进的GE可以通过持续的CHO存储来获得潜在的性能优势.
相关概念视频
Muscle fatigue refers to the decline in a muscle's ability to maintain the force of contraction after prolonged activity. It primarily stems from changes within muscle fibers. Even before experiencing muscle fatigue, one may feel tired and have the urge to stop the activity. This response, known as central fatigue, occurs due to changes in the central nervous system, namely the brain and spinal cord. While there is no single mechanism that induces fatigue, it may serve as a protective...
Pyruvate is the end product of glycolysis, where glucose is oxidized to pyruvate, simultaneously reducing NAD+ to NADH. Two molecules of ATP are also produced by substrate-level phosphorylation.
In aerobic organisms, pyruvate is metabolized via the citric acid cycle to produce reduced coenzymes NADH and FADH2. These coenzymes are then oxidized in the electron transport chain to produce ATP and, in the process, regenerate the NAD+ and FAD. As seen in some cell types and organisms, fermentation...
During the initial hours of fasting, the body uses up its glycogen stores as an energy source. Once these glycogen reserves are depleted, the body begins breaking down stored triglycerides and structural proteins. During this stage, glycerol becomes a key substrate for gluconeogenesis, while free fatty acids undergo beta-oxidation to provide energy for tissues, such as skeletal muscle. In the fasting state, the body spares protein breakdown as much as possible to conserve muscle and structural...
The human body is a powerhouse of energy, with every cell performing numerous functions that require energy. This energy production and consumption is measured by the metabolic rate, which quantifies the total heat generated by all the body's chemical reactions and mechanical work. This measurement helps to determine the rate of kilocalorie (kcal) consumption needed to fuel all ongoing activities.
The Basal Metabolic Rate (BMR) measures the energy expended at rest.
Several factors influence...
The postabsorptive state usually starts about four hours after a meal and lasts until the next meal is eaten. During this time, the digestive system stops absorbing nutrients, and the body uses stored energy reserves to maintain stable blood glucose levels.
Initially, glycogen stored in the liver is broken down to release glucose into the bloodstream, while glycogen in the muscles is broken down to supply glucose for energy directly within the muscle cells. As glycogen stores diminish,...
The hypothetical Carnot cycle consists of an ideal gas subjected to two isothermal and two adiabatic processes. Since the internal energy of an ideal gas depends only on its temperature, which is the same before and after the completion of the Carnot cycle, there is no change in its internal energy. Hence, using the first law of thermodynamics, the total heat exchanged by the ideal gas equals the total work done. Thus, we can quantify the efficiency of the Carnot cycle via the heat exchanged...

