Introduction: Performance on cardiopulmonary exercise test (CPET) is influenced by genetic, racial and environmental factors. It is important to establish a set of reference values for the Filipino population. This study aimed to establish the maximum working capacity, peak oxygen uptake (VO2), peak carbon dioxide output (VCO2), tidal volume (TV) for normal Filipinos during exercise; determine the median perceived rate of exertion using the Borg Scale; and derive prediction equation models for maximum working capacity, peak VO2, peak VCO2 and maximum attained TV.

Methods: The maximal cardiopulmonary responses were analyzed for 118 healthy sedentary adult Filipino subjects who underwent CPET using a symptom limited incremental progressive cycle ergometer driven protocol. A Vista Mini- CPX Model 17670 was used. Models for predicting VO2 max, VCO2 peak, TV peak, and work max were derived with height, weight, age and sex being screened for significance as predictors. Linear and non-linear regression analyses were done.

Results: The maximum working capacity for males was 154.21+26.6 watts and 93.02+15.57 watts for females while the peak VO2 for males was 4.90+3.11 and 4.56 2.41 liters/ minute for females. The predictive formulae derived from this study for maximum work capacity, peak VO2, VCO2 and tidal volume had acceptable correlation coefficients and performed as well as other published predictive equations based on Caucasian and Asian populations.

Discussion: Differences between races as to performance in exercise testing was confirmed in this study so that it is worthwhile to utilize predictive equations specific for a certain racial population in the accurate interpretation of results. Performance in an exercise test also depends on the exercise protocol used so that the predictive equations in this study can be used only for exercise tests using a similar protocol.

Conclusion: Cardiopulmonary exercise testing was performed on a community based, healthy, sedentary Filipino population using a standard maximal incremental cycle ergometry protocol. Predictive equation models were derived for Maximum Working Capacity (r2=0.728), peak VO2 (r2= 0.123), peak VCO2 (r2=0.648), and TV (r2=0.579). The derived predictive formulae performed as well as other published predictive equations.

Keywords: cardiopulmonary exercise test; Philippine normal reference values

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