Simulated obesity-related restrictive ventilatory load impairs moderate exercise sustainability in nonobese men

Tom K K Tong*, Kui Lu, Binh Quach

*Corresponding author for this work

    Research output: Contribution to journalJournal articlepeer-review

    1 Citation (Scopus)


    This study aims in investigating the effects of simulating obesity-related restrictive ventilatory load (RVL) with external thoracic restriction (ETR) on sustaining moderate exercise and on associated cardio-respiratory responses, perceived breathlessness sensation and ventilatory muscle fatigue in nonobese men. Seven male adults with body fat <15% performed two identical exhaustive constant-load moderate cycle exercises with their resting total respiratory elastance either increased twofold by the ETR, with concomitant reduction in functional residual capacity in the RVL trial, or not manipulated in the control trial. In RVL condition, the ETR induced inspiratory muscle fatigue (as indicated by the reduction in post-exercise static maximum mouth pressure) and shortened the exercise time to exhaustion in all subjects (p < 0.05). At exhaustion, hyperventilation composed of rapid and shallow breathing pattern and decreased end-tidal CO2 tension occurred, while arterial O 2 saturation and whole-body O2 consumption were maintained in the control group. Subjective rating of perceived breathlessness sensation (RPB) was increased in the RVL condition (p < 0.05). The increase in RPB was correlated to the reduction in exercise sustainability (r = -0.83). Such findings implied that the perceived sensation of breathlessness in obesity mediated by obesity-related RVL during moderate exercise might contribute to their inferior exercise tolerance.

    Original languageEnglish
    Pages (from-to)42-51
    Number of pages10
    JournalJournal of Exercise Science and Fitness
    Issue number1
    Publication statusPublished - 2006

    Scopus Subject Areas

    • Physical Therapy, Sports Therapy and Rehabilitation
    • Public Health, Environmental and Occupational Health

    User-Defined Keywords

    • Breathlessness
    • Inspiratory muscle fatigue
    • Total respiratory elastance


    Dive into the research topics of 'Simulated obesity-related restrictive ventilatory load impairs moderate exercise sustainability in nonobese men'. Together they form a unique fingerprint.

    Cite this