The goal of this clinical trial is to learn if inspiratory muscle training (IMT) works to treat on clinical symptom severity and quality of life in patients with Non-erosive reflux disease (NERD). The main questions it aims to answer are:
Does drug IMT lower the clinical symptom severity ? Does drug IMT improve quality of life? Researchers will compare high intensity IMT to a sham-IMT (a IMT device with no resistance) to see if IMT lower the clinical symptom severity and improve improve quality of life.
Participants will perform the following protocol:
The IMT protocol will consist of home-based high-intensity training using a Threshold IMT device: two sets of 30 breaths with a 1-minute rest, twice daily for 4 weeks. The study group will train at 60% of baseline maximum inspiratory pressure (MIP), with weekly adjustments based on modified Borg scores (4-6), while the control group will perform sham IMT without resistance.
A clinical diagnosis of NERD,
No erosive lesions on endoscopy,
Presence of reflux symptoms for at least 3 months.
Current use of proton pump inhibitors (PPIs) or failure to complete a minimum 2-week washout period before enrollment.
With known gastroduodenal ulcers
Diagnosed with erosive esophagitis
With hiatal hernia