Análise da existência de máxima fase estável de lactato nos exercícios resistidos leg press 45º e supino reto

Abstract

MAGOSSO, R. F. Analysis of the existance of a maximal lactate steady state on resistance exercises leg press 45° and bench press. 2010. 97f. Dissertacao (Mestrado). Programa de Pos-graduacao Interunidades em Bioengenharia EESC/FMRP/IQSC, Universidade de Sao Paulo (USP), Sao Carlos, 2010. The purpose of the study was to verify if there is a maximal lactate steady state (MLSS) for the Leg Press (LP) and Bench Press (BP) exercises and to analyse ventilatory responses ventilation (Ve) and oxygen uptake (VO2), heart rate (HR), blood lactate concentration (BLC) and ratings of perceived exertion (RPE) to those exercises performed on MLSS intensity and to compare those responses for the exercises. 12 young healthy men with a minimal experience of 6 months of resistance training volunteered for the study. Volunteers underwent a 1 repetition maximum test (1RM), na incremental test to determine anaerobic threshold (AT) and three more sessions to determine MLSS. Session were performed on the same time of Day and separeted by a 48-72h interval. 1RM values for LP and BP were 298,0 ± 36,6kg and 93,7 ± 21,8kg, respectively. The maximal intensity in the incremental test was 70 ± 12,25% of 1RM for LP and 50,00 ± 8,16% of 1RM for BP, which was a significant difference (p˂0,05). Post-test blood lactate concentration (BLS) was also significantly higher for LP (8,36 ± 2,34 vs. 5,43 ± 1,12 mmol/L, respectively) (p˂0,05). AT intensity and was not significantly different for LP and BP (27,9 ± 3,7% vs. 24,1 ± 3,6, respectively). BLC on AT was not significantly different for LP (2,29 ± 0,58 mmol/L) and BP (2,52 ± 0,65). MLSS intensity on LP (29,17 ± 7,02% of 1RM) was significantly higher (p˂0,05) compared to MFEL on BP (21,67 ± 4,44% of 1RM). When compared to AT, MLSS intensity for LP was not significantly different, but for BP it was significantly lower. During exercise on MLSS, oxygen uptake and ventilation, HR and RPE rose significantly compares to rest and then stabilized. There were no differences between exercises. These results show that it is possible to identify a MLSS on the LP and BP exercises, and that for LP this intensity is higher. The differences found between exercises can be atributted to the intrinsic caractheristics of each exercise. Key-words: resistance exercise, anaerobic threshold, maximal lacatate steady state, ventilatory parameters, heart rate, ratings of perceived exertion LISTA DE ABREVIATURAS: 1RM: 1 repeticao maxima AT: limiar anaerobio EPOC: excess post-execise oxygen consumption = consumo excessivo de oxigenio pos exercicio FC: frequencia cardiaca LP: leg press MFEL: maxima fase estavel de lactato PSE: percepcao subjetiva de esforco SR: supino reto Ve: ventilacao VO2 : consumo de oxigenio VO2max: consumo maximo de oxigenio VO2pico: consumo pico de oxigenio