Introduction and objectives: Vocal fatigue is one of the most common voice symptoms. It usually refers to the sensation of vocal tiredness after a long period of speaking or singing. The purpose of this study was to compare the acoustic characteristics of the voice before and after a long period of voice use in a group of radio broadcasters. Methods: Eight radio broadcasters with normal voices were assessed. We used cepstrum, energy ratio, noise to harmonic ratio and soft phonation index as acoustic variables to assess the possible pre-post vocal loading changes objectively. Results: There were no statistically significant pre-post differences in any of the acoustic parameters. Although cepstrum at high pitch did not show a significant difference, it obtained the greatest difference among the acoustic variables. Conclusions: The acoustic measurements used in the present study might not be sensitive enough or appropriate for detecting vocal changes after a long period of voice use, whether in reading (as reported in previous research) or speaking tasks. Moreover, a longer period of vocal loading would eventually reveal more evident and consistent acoustic voice changes. © 2012 Elsevier España, S.L.