TY - JOUR
T1 - Inspiratory pressure waveform influences time to failure, respiratory muscle fatigue, and metabolism during resistive breathing
AU - Poulsen, Mathias Krogh
AU - Rees, Stephen Edward
AU - Hansen, John
AU - Stevenson, Andrew James Thomas
AU - Kjærgaard, Søren Christensen
AU - Volta, Carlo Alberto
AU - Spadaro, Savino
AU - Karbing, Dan Stieper
N1 - © 2023 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.
PY - 2023/5/5
Y1 - 2023/5/5
N2 - Increased ventilatory work beyond working capacity of the respiratory muscles can induce fatigue, resulting in limited respiratory muscle endurance (Tlim). Previous resistive breathing investigations all applied square wave inspiratory pressure as fatigue-inducing pattern. Spontaneous breathing pressure pattern more closely approximate a triangle waveform. This study aimed at comparing Tlim, maximal inspiratory pressure (PImax), and metabolism between square and triangle wave breathing. Eight healthy subjects (Wei = 76 ± 10 kg, H = 181 ± 7.9 cm, age = 33.5 ± 4.8 years, sex [F/M] = 1/7) completed the study, comprising two randomized matched load resistive breathing trials with square and triangle wave inspiratory pressure waveform. Tlim decreased with a mean difference of 8 ± 7.2 min (p = 0.01) between square and triangle wave breathing. PImax was reduced following square wave (p = 0.04) but not for triangle wave breathing (p = 0.88). Higher VO2 was observed in the beginning and end for the triangle wave breathing compared with the square wave breathing (p = 0.036 and p = 0.048). Despite higher metabolism, Tlim was significantly longer in triangle wave breathing compared with square wave breathing, showing that the pressure waveform has an impact on the function and endurance of the respiratory muscles.
AB - Increased ventilatory work beyond working capacity of the respiratory muscles can induce fatigue, resulting in limited respiratory muscle endurance (Tlim). Previous resistive breathing investigations all applied square wave inspiratory pressure as fatigue-inducing pattern. Spontaneous breathing pressure pattern more closely approximate a triangle waveform. This study aimed at comparing Tlim, maximal inspiratory pressure (PImax), and metabolism between square and triangle wave breathing. Eight healthy subjects (Wei = 76 ± 10 kg, H = 181 ± 7.9 cm, age = 33.5 ± 4.8 years, sex [F/M] = 1/7) completed the study, comprising two randomized matched load resistive breathing trials with square and triangle wave inspiratory pressure waveform. Tlim decreased with a mean difference of 8 ± 7.2 min (p = 0.01) between square and triangle wave breathing. PImax was reduced following square wave (p = 0.04) but not for triangle wave breathing (p = 0.88). Higher VO2 was observed in the beginning and end for the triangle wave breathing compared with the square wave breathing (p = 0.036 and p = 0.048). Despite higher metabolism, Tlim was significantly longer in triangle wave breathing compared with square wave breathing, showing that the pressure waveform has an impact on the function and endurance of the respiratory muscles.
KW - Adult
KW - Humans
KW - Muscle Fatigue/physiology
KW - Respiration
KW - Respiratory Insufficiency
KW - Respiratory Muscles/physiology
KW - Respiratory Rate
KW - resistive breathing
KW - respiration pattern
KW - muscle fatigue
KW - respiratory muscles
UR - http://www.scopus.com/inward/record.url?scp=85159309350&partnerID=8YFLogxK
U2 - 10.14814/phy2.15668
DO - 10.14814/phy2.15668
M3 - Journal article
C2 - 37147887
SN - 2051-817X
VL - 11
JO - Physiological Reports
JF - Physiological Reports
IS - 9
M1 - e15668
ER -