The respiratory metaboreflex is a physiological response to increased carbon dioxide (CO2) and decreased oxygen (O2) in the blood. It is part of the body's regulatory mechanisms to maintain homeostasis regarding respiratory and cardiovascular functions.

The respiratory metaboreflex regulates blood flow to the respiratory muscles during exercise. When CO2 accumulates and O2 decreases, receptors in the muscles and blood vessels, known as metaboreceptors, are activated. These receptors sense the metabolic byproducts of muscle activity, such as lactic acid and adenosine triphosphate (ATP). The activation of metaboreceptors sends signals to the respiratory and cardiovascular centers in the brainstem.

The main effect of the respiratory metaboreflex is an increase in ventilation or breathing rate. By increasing the respiratory rate, the body attempts to eliminate excess CO2 and replenish O2 levels. Additionally, the cardiovascular response involves increased heart rate and cardiac output to improve blood flow and oxygen delivery to the working muscles.

IMT involves exercises to strengthen the muscles involved in breathing, specifically the inspiratory muscles (like the diaphragm and intercostal muscles). Studies suggest that IMT provided with a PrO2 device utilizing the TIRE protocol can improve the strength and endurance of these muscles. Enhancing the strength and endurance of respiratory muscles through IMT can improve their efficiency and reduce the production of metabolic byproducts during exercise.

Therefore, IMT can indirectly benefit it by improving the overall efficiency and endurance of the respiratory muscles. This improvement may lead to reduced fatigue, better oxygen utilization, and possibly less activation of the metaboreceptors during exercise, thus optimizing respiratory muscle function.

The respiratory metaboreflex plays a crucial role in maintaining the balance of gases in the blood during physical activity and is an essential component of overall respiratory and cardiovascular regulation.