Abstract : It has been shown that a pedaling frequency component can be extracted from the heart rate variability (HRV) signal using a time-varying filter. It is shown that this filter can be implemented directly in the time-frequency plane with different approaches. The need of resampling the data is also discussed with regard to the artifacts produced when the shanon condition is not fulfilled. In order to interpret the similar amplitude profiles of the pedaling component for untrained and trained subjects, an attempt for the model parameters setting is proposed. Consistent results on a large data set illustrate the feasibility of such processing.