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Sports Physiology TIME COURSE CHANGES AND PHYSIOLOGICAL FACTORS RELATED TO CENTRAL AND PERIPHERAL DETERMINANTS OF PERCEIVED EXERTION IN HIGHLY TRAINED ADOLESCENT ALPINE SKIERS

LINDA M. LEMURA, SERGE P. VON DUVILLARD, FRANK STANEK. Time Course Changes And Physiological Factors Related To Central And Peripheral Determinants Of Perceived Exertion In Highly Trained Adolescent Alpine Skiers JEPonline. 2001;4(4):29-40. The purposes of this study were 1) to investigate changes in respiratory-metabolic (central) and peripheral (local) determinants of perceived exertion (RPE) in highly trained adolescent alpine ski competitors on a mechanically braked cycle ergometer, and 2) to test the efficacy of utilizing two different scales to determine differentiated RPE. Thirteen adolescents (3 females and 10 males) performed an incremental graded exercise test (GXT) consisting of two-minute stages. The average maximal oxygen consumption (VO2 max) achieved by this group was 52.9±6.8 ml/kg/min. Blood samples were collected at the end of each two-minute exercise stage and analyzed for lactate concentration (LA). Participants provided a measure of RPE at the end of each exercise stage for the duration of the test for both central or respiratory-metabolic (Borg scale 6-20) and peripheral or local (Borg scale 0-10) factors associated with effort sensation. Correlation analyses revealed that the RPE measured by Borg=6-20 scale was significantly related (r=0.89; p<0.05) to lactate accumulation throughout the GXT. Central exertion values (RPE-C vs. VO2, r=0.94; p<0.05 and RPE-C vs. VE r=0.98; p<0.05) were significantly higher at 3 distinct phases of the graded exercise test when compared to peripheral exertion values. Our data indicate that the sensory cues used to select an RPE value coincide with a combination of central and peripheral mediators at varying phases of the incremental test, and that one physiological mediator may predominate over another in shaping perceptional responses in this group. Furthermore, the utility of the two-scale approach lies in encouraging participants to think critically about RPE selections, even at the highest intensities of the GXT.