Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disorder that impairs motor neurons, with a life expectancy of 2 to 7 years after diagnosis. ALS manifests as 'spinal' when it primarily affects limbs, or 'bulbar' when it impairs speech and swallowing. The disease progressively weakens all skeletal muscles, causing respiratory issues and increased risk of lung infections due to ineffective coughing. Mechanical cough assistance via In-exsufflation therapy/ mechanical in-exsufflator devie (INEX/MI-E) applies positive and negative airway pressures non-invasively to improve coughing. However, MI-E may fail in some ALS patients due to airway collapse, often related to brainstem muscle dysfunction.Research by Andersen et al. in 2017 highlighted that during MI-E, ALS patients often experience adverse laryngeal movements, which can obstruct airways and reduce the therapy's effectiveness. To combat this, they suggested individualized MI-E settings to minimize airway collapse. Modern MI-E devices, such as the EOVE-70, offer adjustable positive expiratory pressure (PEP) between cycles to potentially enhance airway stability and coughing efficiency. The current study focuses on the impact of PEP during therapy pauses on the peak expiratory flow rate in ALS patients, which could lead to improved therapeutic outcomes.