Inspiratory muscle training enhances recovery post-COVID-19: a randomised controlled trial

Abstract

BackgroundMany people recovering from COVID-19 experience prolonged symptoms, particularly breathlessness. We urgently need to identify safe and effective COVID-19 rehabilitative strategies. The aim of the current study was to investigate the potential rehabilitative role of inspiratory muscle training (IMT).Methods281 adults (46.6±12.2 years; 88% female) recovering from self-reported COVID-19 (9.0±4.2 months post-acute infection) were randomised 4:1 to an 8-week IMT or a “usual care” wait list control arm. Health-related quality of life and breathlessness questionnaires (King's Brief Interstitial Lung Disease (KBILD) and Transition Dyspnoea Index (TDI)), respiratory muscle strength and fitness (Chester Step Test) were assessed pre- and post-intervention. The primary endpoint was KBILD total score, with the KBILD subdomains and TDI being key secondary outcomes.ResultsAccording to intention to treat (ITT), there was no difference between groups in KBILD total score post-intervention (Control: 59.5±12.4; IMT: 58.2±12.3; p<0.05) but IMT elicited clinically meaningful improvements in the KBILD subdomains of breathlessness (Control: 59.8±12.6; IMT: 62.2±16.2; p<0.05) and chest symptoms (Control: 59.2±18.7; IMT: 64.5±18.2; p<0.05), along with clinically meaningful improvements in breathlessness according to TDI (Control: 0.9±1.7 versus 2.0±2.0; p<0.05). IMT also improved respiratory muscle strength and estimated aerobic fitness.ConclusionsIMT may represent an important home-based rehabilitation strategy for wider implementation as part of COVID-19 rehabilitative strategies. Given the diverse nature of long-COVID, further research is warranted on the individual responses to rehabilitation - the withdrawal rate herein highlights that no one strategy is likely to be appropriate for all.

Influence of Manual Diaphragm Release Technique Combined with Inspiratory Muscle Training on Selected Persistent Symptoms in Men with Post-Covid-19 Syndrome: A Randomized Controlled Trial

“…Moreover, the findings of the current study showed a statistically significant decrease in dyspnoea in favour of the study group, in which the MMRC scale decreased by 48.9% ( p < 0.001), whereas in the control group, it decreased by 12.8% ( p < 0.01). This is compatible with McNarry et al ( 35 ), who demonstrated that IMT can dramatically enhance long-term COVID patients’ dyspnoea, respiratory muscle function, and functional capacity. Furthermore, in recovered COVID-19 patients, Abodonya et al ( 14 ) found that IMT improved pulmonary functioning, dyspnoea, and fatigue, which is also supported by Nopp et al ( 36 ).…”

Self-Assessed Aspects of Health 3 Months after COVID-19 Hospitalization—A Swedish Cross-Sectional Study

“…Though breathlessness is a common symptom of COVID-19 [1], progress of the respiratory impairments over time is not yet known. These results may indicate a need for respiratory follow-up after hospital discharge in these patients, also including respiratory physical therapy with inspiratory muscle training to manage breathlessness and regain inspiratory muscle function [32].…”

Long COVID: mechanisms, risk factors and recovery

“…Although SARS-CoV-2 is primarily a respiratory infection, it is a multi-system disease (Merad et al, 2022), including the nervous system. Understanding how dysfunction affects different interacting organ systems is important for understanding this disease, and discovering the abnormal subcellular alterations in function is likely to be vital for developing effective treatment strategies.…”