Is parasternal intercostal EMG an accurate surrogate of respiratory neural drive and biomarker of dyspnea during cycle exercise testing?

Andrew H Ramsook; Reid A Mitchell; Tyson Bell; Suzanne Calli; Chris Kennedy; Jenny Lehmann; Matt Thompson; Joseph H Puyat; Jordan A Guenette

doi:10.1016/j.resp.2017.03.003

Is parasternal intercostal EMG an accurate surrogate of respiratory neural drive and biomarker of dyspnea during cycle exercise testing?

Respir Physiol Neurobiol. 2017 Aug:242:40-44. doi: 10.1016/j.resp.2017.03.003. Epub 2017 Mar 20.

Authors

Andrew H Ramsook¹, Reid A Mitchell¹, Tyson Bell², Suzanne Calli², Chris Kennedy², Jenny Lehmann², Matt Thompson², Joseph H Puyat³, Jordan A Guenette⁴

Affiliations

¹ Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, Vancouver, BC, Canada; Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada.
² Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada.
³ Centre for Health Evaluation & Outcome Sciences, Providence Health Care Research Institute, University of British Columbia, St. Paul's Hospital, Vancouver, BC, Canada.
⁴ Centre for Heart Lung Innovation, University of British Columbia and St. Paul's Hospital, Vancouver, BC, Canada; Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada. Electronic address: jordan.guenette@hli.ubc.ca.

PMID: 28336390
DOI: 10.1016/j.resp.2017.03.003

Abstract

Recent evidence suggests that surface electromyography of the parasternal intercostals (EMGpara) can be a non-invasive alternative to diaphragmatic EMG (EMGdi) for estimating neural respiratory drive (NRD) during cardiopulmonary exercise testing (CPET). The purpose of this study was to determine if non-respiratory muscles influence EMGpara by having subjects place their hands on (H_on) and off (H_off) the handlebars during cycling-based CPET. Ten healthy adults performed an incremental cycling test until volitional exhaustion. Participants were instrumented with an esophageal electrode catheter to measure EMGdi, and surface electrodes on the 2nd intercostal space to measure EMGpara. Subjects alternated between 30s of H_on and 30s H_off during each exercise stage. There were no differences in EMGdi across all exercise intensities. However, EMGpara was significantly greater during the H_on vs. H_off condition at all exercise intensities (p<0.05). These results suggest that EMGpara may not be an appropriate surrogate of NRD during cycle exercise testing due to co-activation of adjacent skeletal muscles.

Keywords: Dyspnea; Electromyography; Exercise; Respiratory muscles.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bicycling / physiology*
Diaphragm / physiopathology*
Dyspnea / physiopathology*
Electromyography
Exercise Test
Exercise Tolerance / physiology
Female
Humans
Intercostal Muscles / physiopathology*
Male
Respiration*
Young Adult