Autonomic dysfunction and exercise intolerance in post-COVID-19 - An as yet underestimated organ system?

Area of Science:

• Cardiorespiratory physiology
• Autonomic nervous system function
• Post-COVID-19 sequelae

Background:

• Persistent symptoms like exercise intolerance and low cardiorespiratory fitness are common in COVID-19 recovery.
• The Wasserman gear system highlights the interplay of heart, lungs, and muscles in determining fitness.
• Peripheral, cardiovascular, and lung diffusion limitations are recognized contributors to post-COVID-19 exercise intolerance.

Purpose of the Study:

• To investigate the role of the autonomic nervous system (ANS) in post-COVID-19 exercise intolerance.
• To propose a psycho-pathophysiological model for ANS involvement in exercise intolerance.
• To encourage a broader examination of physiological systems contributing to post-COVID-19 symptoms.

Main Methods:

• Review and discussion of existing literature on the ANS and exercise physiology.
• Identification of four potential pathways through which the ANS may contribute to exercise intolerance.
• Synthesis of these pathways into a conceptual psycho-pathophysiological model.

Main Results:

• The autonomic nervous system has received limited attention in the context of post-COVID-19 exercise intolerance.
• Four key pathways are proposed: altered cerebral hemodynamics, aberrant afferent/efferent signaling, central hypersensitivity, and changes in physical activity appraisal/engagement.
• These pathways offer a framework for understanding ANS contributions to persistent symptoms.

Conclusions:

• The autonomic nervous system is a crucial, yet understudied, factor in post-COVID-19 exercise intolerance.
• A comprehensive understanding requires considering the ANS alongside pulmonary, cardiovascular, and peripheral factors.
• Further research into the ANS is warranted to develop effective interventions for post-COVID-19 exercise intolerance.