Name: VANESSA CÂNDIDO ABREU
Publication date: 04/04/2017
Advisor:
Name |
Role |
|---|---|
| LUCIANA CARLETTI | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| LUCIANA CARLETTI | Advisor * |
Summary: The VO2max is traditionally identified by the occurrence of the plateau at maximum effort. The classic criterion for plateau identification was proposed by Taylor et al. (1955). However, due to criticism of this method, several criteria, different analysis times and protocols appeared that resulted in the lack of consensus among the scientists on which would be the most appropriate method for the identification of the plateau, impairing the comparison and reproducibility between the studies, as well as the quality of the studies. The dissertation consisted of two studies described below: Study I, whose objective was to investigate the methods of identification and the occurrence of the VO2max plateau, describing the procedures for data collection and analysis. Searches were performed in PUBMED and BIREME databases. From the results, we excluded work with animals, individuals with pathologies, with only women or children and adolescents, articles of revision, written in a language other than English or that did not use the plateau. There was a great variation in the occurrence of plateau (4,8% to 100%), and diversity of test protocols (ramp predominance), analysis times (predominantly 10 to 20s and 30s) and different analysis criteria (Threshold of consecutive differences and statistical criteria). It is concluded that the problems of occurrence and methodology of the identification of the VO2max plateau presented in this systematic review, result in very divergent works regarding the percentage of occurrence of the plateau and in confused and misrepresented criteria. In sequence, Study II proposed a new analysis model for the VO2max plateau using individualized criteria and statistical analysis and to identify the physical fitness characteristics of the subjects who perform a VO2max plateau by the proposed model. The sample consisted of 31 male runners (age between 18 and 40 years). Subjects were submitted to resting electrocardiogram and cardiopulmonary exercise test, using the ramp protocol to verify VO2max and other physiological variables. The data were tabulated from breath by breath. The identification of the VO2max plateau was performed through segmented linear regression with unknown breakpoints for each test. Of the sample, 58,06% presented plateau of VO2max, no statistically significant differences were found in metabolic, ventilatory and velocity variables. It is concluded that this model has advantages because it is adapted to the ramp protocol, to analyze VO2 variations individually and by the use of statistical method. And yet, from the data analyzed there is no difference in the fitness characteristics between the groups.
