Impact of expiratory strength training in amyotrophic lateral sclerosis

Abstract

Introduction We evaluated the feasibility and impact of Expiratory Muscle Strength Training (EMST) on respiratory and bulbar function in persons with amyotrophic lateral sclerosis (ALS). Methods 25 ALS patients participated in this delayed intervention open-label clinical trial. Following a lead-in period, patients completed a 5-week EMST protocol. Outcome measures included: maximum expiratory pressure (MEP), physiologic measures of swallow and cough, and Penetration-Aspiration Scale (PAS) scores. Results Of those participants who entered the active phase of the study (n=15), EMST was well tolerated and led to significant increases in MEPs and maximum hyoid displacement during swallowing post-EMST (P<0.05). No significant differences were observed for PAS scores or cough spirometry measures. Discussion EMST was feasible and well tolerated in this small cohort of ALS patients and led to improvements in expiratory force-generating pressures and swallow kinematics. Further investigation is warranted to confirm these preliminary findings.

Expiratory muscle strength training for radiation‐associated aspiration after head and neck cancer: A case series

“…Dysphagia research has increasingly considered downstream targets in the respiratory system to improve airway protection in dysphagic populations and populations at risk for aspiration (such as those with progressive neurodegenerative conditions like PD and ALS) . In this case series of HNC survivors with chronic aspiration, we observed the MEPs improved by 57% among those who completed 8 weeks of a resistance exercise in the EMST therapy program.…”

“…During EMST, a patient expires forcefully into a one‐way spring‐loaded valve that can be tightened incrementally to increase resistance of the exercise task to strengthen recruited muscles over time. For patients with swallowing impairment, EMST is thought to act on one of two mechanisms to improve airway protection: 1) strengthening subglottic expiratory pressure‐generating forces, translating to a stronger cough to clear aspirate from the lower airway; or 2) improving airway closure for swallowing by exercise of swallowing‐related muscles, such as those in the submental suprahyoid region . Trials examining a progressive‐resistive exercise paradigm of EMST in patients with or at risk for dysphagia related to neurogenic pathologies (i.e., Parkinson disease [PD], amyotrophic lateral sclerosis [ALS], and stroke) report improvement in airway protection after a 5‐week strengthening exercise program (detailed summary in Table ) .…”

Trends in Research Literature Describing Dysphagia in Motor Neuron Diseases (MND): A Scoping Review

“…Still, the majority of studies reporting swallowing physiology/function present observations in descriptive terms, limiting our ability to compare results across studies or measure discrete degrees of change. For example, hyolaryngeal excursion is often reported as “reduced” (e.g., [33,45,60]), however, when measured in reference to a scalar or anatomical marker, the results are more variable (e.g., [51,65]). Quantification of swallowing physiology has largely been limited to studies using manometry (e.g., [40,59,66]) and EMG (e.g., [67,68]).…”

“…Recordings taken from EMG have identified longer swallow durations [67,68,72], variability in cricopharyngeal pause duration [68,72], and discoordination between the timing of laryngeal excursion and cricopharyngeal relaxation [72]. Additional tools used as part of a swallowing assessment, including spirometry/airflow measures, tongue pressure measurement, and sonography, have identified (respectively): irregularities in voluntary cough airflow and respiratory-swallow coordination [67,73–75], reduced swallow pressures and maximum isometric tongue strength [52,76–78], and reduced tongue thickness and reduced/disorganized tongue movement during swallowing [29,78,79]. Taken together, research to-date has generated a great deal of information regarding the physiological and functional differences of swallowing that may be observed in individuals with MND.…”

The level of effort, rather than muscle exercise intensity determines strength gain following a six-week training

“…The application of this finding to medical rehabilitation is obvious as many frail patients and elderly persons are afraid of or feel difficult in engaging in high-intensity physical training such as weightlifting, yet these individuals are capable to carry out strong-willed mental exercises alone or combined with low- to moderate-level muscle contractions to strengthen their muscles [21]. Weakness is considered as a primary factor contributing to physical disability in aging [22–23] and other conditions [24–25]; yet, individuals with prominent muscle weakness are ones mostly challenged by conventional strength training. The finding of the current study points to a beneficial and cost-effective muscle strengthening therapy for populations enduring significant weakness.…”