Dose-Response Effects of Inspiratory Muscle Strength Training on Blood Pressure and Vascular Function

Inclusion criteria

• Age ≥18 years
• Resting SBP ≥120 mmHg as measured during screening 1 & 2
• Free from serious CV or metabolic diseases as identified by self-report and blood chemistry analysis.
• No contraindications to IMST (recent abdominal surgery, ruptured eardrum, asthma with very low symptom perception, fractured ribs, or pneumothorax)
• Language: English-speaking, with ability to comprehend study materials and instructions.
• Pre-visit Compliance: Willing to comply with pre-visit instructions (avoiding food and caffeine ≥ 3 hours, vigorous exercise, alcohol, and non-prescribed medications ≥ 24 hours) prior to each measurement visit.
• Lifestyle: Non-smokers (defined as self-report of not smoking cigarettes or vaping over the past year).

Exclusion criteria

• Self-report of history of cardiovascular disease, or conditions affecting the ear (e.g., ruptured eardrum).
• Recent abdominal surgery or presence of an abdominal hernia.
• Asthma with very low symptom perception, frequent severe exacerbations, or abnormally low perception of dyspnea.
• Ruptured eardrum or any other condition of the ear.
• Markedly elevated left ventricular end-diastolic volume and pressure.
• Current respiratory conditions such as a cold, sinusitis, or respiratory tract infection (participants may be included once they recover from the respiratory condition).
• Female-Specific: Pregnant or planning to become pregnant during the study period.
• Compliance: Unable or unwilling to comply with pre-visit restrictions (e.g., avoiding caffeine, alcohol, and exercise within specified hours before visits).