Laboratory of Physical Activity and Health Promotion, Institute of Physical Education and Sports, University of Rio de Janeiro State, Rua São Francisco Xavier, 524, sala 8133F, Maracanã, Rio de Janeiro, RJ, CEP, 20550-013, Brazil.
Graduate Program in Exercise and Sports Sciences, University of Rio de Janeiro State, Rio de Janeiro, RJ, Brazil.
Eur J Appl Physiol. 2021 Nov;121(11):2943-2955. doi: 10.1007/s00421-021-04756-8. Epub 2021 Jun 29.
Abnormalities in the muscle metaboreflex concur to exercise intolerance and greater cardiovascular risk. Exercise training benefits neurocardiovascular function at rest and during exercise, but its role in favoring muscle metaboreflex in health and disease remains controversial. While some authors demonstrated that exercise training enhanced the sensitization of muscle metabolically afferents and improved neurocardiovascular responses to muscle metaboreflex activation, others reported unaltered responses. This narrative review aimed to: (a) highlight the current evidence on the effects of exercise training upon cardiovascular and autonomic responses to muscle metaboreflex activation; (b) analyze the role of training components and indicate potential mechanisms of metaboreflex adaptations; and (c) address key methodological features for future research. Though limited, accumulated evidence suggests that muscle metaboreflex adaptations depend on the individual clinical status, exercise modality, and training duration. In healthy populations, most trials negated the hypothesis of metaboreflex improvement due to chronic exercise, irrespective of the training duration. Favorable changes in patients with impaired metaboreflex, particularly chronic heart failure, mostly resulted from long-term interventions (> 16 weeks) including aerobic exercise of moderate to high intensity, performed in isolation or within multimodal training. Potential mechanisms of metaboreflex improvements include enhanced sensitivity of channels and receptors, greater antioxidant capacity, lower metabolite accumulation, increased functional sympatholysis, and muscle perfusion. Future research should investigate: (1) the dose-response relationship of training components within different exercise modalities to elicit improvements in individuals showing intact or impaired muscle metaboreflex; and (2) potential and specific underlying mechanisms of metaboreflex improvements in individuals with different medical conditions.
肌肉代谢反射异常与运动不耐受和更大的心血管风险相关。运动训练有益于静息和运动时的神经心血管功能，但它在促进健康和疾病中的肌肉代谢反射的作用仍存在争议。虽然一些作者证明了运动训练增强了肌肉代谢传入纤维的敏感性，并改善了对肌肉代谢反射激活的神经心血管反应，但其他人报告说反应没有改变。本综述旨在：（a）强调运动训练对肌肉代谢反射激活的心血管和自主神经反应的影响的现有证据；（b）分析训练成分的作用，并指出代谢反射适应的潜在机制；（c）解决未来研究的关键方法学特征。尽管有限，但积累的证据表明，肌肉代谢反射适应取决于个体的临床状况、运动方式和训练持续时间。在健康人群中，大多数试验否定了慢性运动改善代谢反射的假设，无论训练持续时间如何。在代谢反射受损的患者中，特别是慢性心力衰竭患者，由于长期干预（>16 周），包括中等至高强度的有氧运动，单独或在多模式训练中进行，往往会产生有利的变化。代谢反射改善的潜在机制包括通道和受体的敏感性增强、抗氧化能力增强、代谢物积累减少、功能性交感神经松弛增加和肌肉灌注增加。未来的研究应调查：（1）不同运动方式的训练成分的剂量-反应关系，以诱发对具有完整或受损肌肉代谢反射的个体的改善；（2）不同医疗条件的个体中代谢反射改善的潜在和特定潜在机制。
