Control of ventilation during submaximal exercise: a brief review

Area of Science:

• Exercise Physiology
• Respiratory Control
• Human Physiology

Background:

• Ventilatory control during exercise is crucial for meeting metabolic demands.
• The rapid increase in ventilation (VE) at exercise onset (exercise hyperpnoea) is a well-documented phenomenon.
• Existing research presents multiple hypotheses regarding the underlying mechanisms of exercise hyperpnoea.

Purpose of the Study:

• To review and discuss the primary hypotheses explaining ventilatory control during submaximal exercise.
• To examine the evidence supporting neural and humoral mechanisms in exercise hyperpnoea.
• To highlight the unresolved questions in the field of exercise-induced ventilation regulation.

Main Methods:

• Literature review of existing hypotheses on ventilatory control during exercise.
• Analysis of proposed neural mechanisms, including afferent and efferent pathways.
• Evaluation of proposed humoral mechanisms, focusing on CO2 return to the lung.
• Consideration of integrated models involving both neural and humoral factors.

Main Results:

• Four main schools of thought exist regarding exercise hyperpnoea: afferent neural feedback, efferent neural activity, humoral mechanisms (CO2 return), and combined neural-humoral control.
• Evidence suggests both neural and humoral factors contribute to the ventilatory response during exercise.
• No single hypothesis has definitively resolved the debate on the primary driver of exercise hyperpnoea.

Conclusions:

• Both neural and humoral mechanisms are likely involved in mediating exercise hyperpnoea.
• The precise contribution and interplay of neural and humoral factors remain an active area of research.
• Further investigation is needed to fully elucidate the complex control of ventilation during exercise.