In:
PLOS ONE, Public Library of Science (PLoS), Vol. 17, No. 12 ( 2022-12-7), p. e0277131-
Abstract:
Fatigue is defined as loss of capacity to develop muscle force and/or velocity that is reversible at rest. We assessed non-invasively the fatigue and recovery of inspiratory rib cage muscles during two respiratory endurance tests in healthy individuals. Methods The sniff nasal inspiratory pressure (SNIP) was assessed before and after two respiratory endurance tests: normocapnic hyperpnea (NH) and inspiratory pressure threshold loading (IPTL). Contractile (maximum rate of pressure development and time to peak pressure) and relaxation parameters (maximum relaxation rate [MRR], time constant of pressure decay [τ] , and half relaxation time) obtained from sniff curves and shortening velocity and mechanical power estimated using optoelectronic plethysmography were analyzed during SNIP maneuvers. Respiratory muscle activity (electromyography) and tissue oxygenation (near-infrared spectroscopy—NIRS) were obtained during endurance tests and SNIP maneuvers. Fatigue development of inspiratory rib cage muscles was assessed according to the slope of decay of median frequency. Results Peak pressure during SNIP decreased after both protocols (p 〈 0.05). MRR, shortening velocity, and mechanical power decreased (p 〈 0.05), whereas τ increased after IPTL (p 〈 0.05). The median frequency of inspiratory rib cage muscles (i.e., sum of sternocleidomastoid, scalene, and parasternal) decreased linearly during IPTL and exponentially during NH, mainly due to the sternocleidomastoid. Conclusion Fatigue development behaved differently between protocols and relaxation properties (MRR and τ), shortening velocity, and mechanical power changed only in the IPTL.
Type of Medium:
Online Resource
ISSN:
1932-6203
DOI:
10.1371/journal.pone.0277131
DOI:
10.1371/journal.pone.0277131.g001
DOI:
10.1371/journal.pone.0277131.g002
DOI:
10.1371/journal.pone.0277131.g003
DOI:
10.1371/journal.pone.0277131.g004
DOI:
10.1371/journal.pone.0277131.g005
DOI:
10.1371/journal.pone.0277131.g006
DOI:
10.1371/journal.pone.0277131.g007
DOI:
10.1371/journal.pone.0277131.g008
DOI:
10.1371/journal.pone.0277131.t001
DOI:
10.1371/journal.pone.0277131.t002
DOI:
10.1371/journal.pone.0277131.s001
DOI:
10.1371/journal.pone.0277131.s002
Language:
English
Publisher:
Public Library of Science (PLoS)
Publication Date:
2022
detail.hit.zdb_id:
2267670-3
Bookmarklink