The exercise pressor response (EPR) is mediated by free nerve endings in muscle (group III/IV fibers) that are able to detect variations of the mechanical and metabolic status of the muscle. Neural feedback from these fibers results in a haemodynamic adjustment to regulate blood flow based on the contracting muscle's status. Metabolic syndrome is a condition that causes alterations of the EPR and other hemodynamic responses to physical activity.

The sensitivity of muscle receptors to changes in the mechanical and metabolic conditions of the muscle (mechano-metabo receptors) is decreased in patients with obesity, insulin resistance, diabetes, or cardiovascular disease. These changes result in a decrease in exercise pressor response that is not accompanied by increases in heart rate or cardiac output.

This is the reason why some studies have shown that the EPR response is decreased in obese subjects and patients with hypertension or diabetes. However, it is still unclear how these alterations in the EPR response occur.

Our aim was to investigate the influence of both isometric and rhythmic handgrip forearm exercise on central hemodynamic parameters (blood pressure, cardiac output, systemic vascular resistance) in subjects with metabolic syndrome. The hemodynamic parameters were assessed using impedance cardiography before and after exercise.

Subjects volunteered for the study. They were matched on age, gender, and physical activity.

A total of 11 healthy volunteers completed the test. The tests included post-exercise muscle ischemia (PEMI) to activate the metaboreflex, control exercise recovery (CER), PEMI + MT, and CER + MT.

During PEMI, the metaboreflex stimulates sympathetic tone without any motor cortex activation. This is a crucial distinction to make because it excludes the possibility of interference caused by motor cortex activity, which may be present during real exercise.

Metabolic USA syndrome has been linked to decreased cerebral oxygenation in response to exercise and the exaggerated increase in systemic vascular resistance (SVR) in these patients during metaboreflex is evidence of impaired COX. Therefore, we aimed to assess the impact of metaboreflex on COX during contemporary mental task (MT) and the effect of a training session using POWERbreathe Inspiratory Muscle Training on the effect of metaboreflex on hemodynamics.