André de Assis Lauria

ACUTE RESPONSES OF RATE PRESSURE PRODUCT IN SETS OF RESISTANCE EXERCISE

Objective: To compare the acute responses of rate pressure product (RPP) between dynamic and isometric sets of resistance exercise (RE); compare the acute responses of RPP between upper and lower limbs in RE. Methods: Nineteen active men (22.7 ± 2.2 years) attended this study in a random crossover model. In the first day they performed hemodynamic measurements and one maximum repetition tests (1RM) in leg press (LGP) and bench press (BCP) exercises. In the second, third, fourth and fifth days they performed the following tests: LGP isometric, BCP isometric, LGP dynamic and BCP dynamic, respectively. Isometric protocols were conducted in 3 sets of 40 s (1 st set: 25% 1RM, 2 nd set: 50% 1RM, 3 rd set: 75% 1RM) and dynamic protocols in 3 sets of 10 repetitions (1 st set: 25% 1RM, 2 nd set: 50% 1RM, 3 th set: 75% 1RM). The RPP was obtained immediately after each set. Results: A comparison between protocols showed that RPP was higher (P < 0.05) in dynamic than in isometric protocol. A comparison between exercises showed that RPP was higher (P < 0.05) in LGP than BCP exercise. Conclusions: In similar relative intensities, the acute cardiac responses are influenced by the exercise protocol, since the RPP was higher in the dynamic condition. Furthermore, RPP seems to be related with recruited muscle mass, since that were observed higher values of RPP in exercises for lower limbs .

Predição da frequência cardíaca basal de indivíduos com níveis de atividade física alto e baixo

INTRODUCAO: A frequencia cardiaca basal (FCbasal) e medida ao despertar, ja que apresenta alteracoes ritmicas ao longo do dia. OBJETIVO: Em vista da dificuldade em conseguir mensurar, o objetivo do estudo foi propor uma equacao de predicao da FCBasal. Para isto, foi necessario, em primeiro lugar, descrever o padrao de ritmicidade da FC e estudar a influencia do nivel de atividade fisica habitual (NAF) sobre tal ritmicidade. METODO: 90 individuos responderam o questionario de Baecke, cuja mediana foi usada para a constituicao dos grupos NAF A e NAF B. Os sujeitos autoavaliaram a FCrep as 6, 9, 12, 15, 18, 21 e 24 h. Para descrever a ritmicidade e identificar a influencia do NAF, aplicou-se ANOVA seguida do teste de Tukey (p > 0,05) aos valores absolutos e normalizados de FCrep. Os valores normalizados foram ajustados por polinomio de segundo grau para construir a equacao de predicao, cuja validade foi testada por correlacao de Pearson (p > 0,05) e erro padrao de estimativa (EPE). RESULTADOS: A FCrep do grupo NAF A foi menor que a do grupo NAF B em todos horarios avaliados: 60 ± 7,5, 64 ± 9,3, 63 ± 8,1, 66 ± 8,7, 66 ± 7,7, 64 ± 8,1 e 60 ± 8,2; em comparacao com: 66 ± 9,6, 71 ± 11,4, 72 ± 11,6, 73 ± 10,8, 74 ± 10,7, 69 ± 9,4 e 68 ± 10,7. Para os valores normalizados, nao foram encontradas diferencas significativas entre os dois grupos, ambos apresentaram padrao de ritmicidade semelhante a uma parabola. A equacao de predicao apresentou r de 0,70 a 0,83 e EPE de 4,8 a 6,2 bpm. CONCLUSAO: A FCrep apresenta valores mais baixos em individuos mais ativos, porem com o mesmo padrao de ritmicidade. E possivel predizer a FCbasal a partir da medicao da FCrep feita em diferentes horarios do dia.

Análise da correlação entre o protocolo Polar Fitness Test® para predição de VO2máx e ergoespirometria

INTRODUCTION: The importance of maximal oxygen consumption (O2max) measurement is justified by its international acceptance as the best physiological parameter to assess the functional capacity of the cardiorespiratory system in both athletes and non-athletes who physically train in order to achieve better health. OBJECTIVE: To determine the agreement between the Polar Fitness Test® protocols to estimate of O2max and the maximal exercise test with direct gas measurement. METHODS: Seventeen active males (22.5 ± 2 years) participated in the study. At rest, the Polar Fitness Test® protocol by direct gas collection under maximum effort on treadmill and the Bruce protocol were applied. RESULTS: Significant difference in the O2max estimation was observed between methods. The Polar Fitness Test® protocol underestimated O2max a mean of 15% (CI95%: 24;-53%) when compared to the direct protocol. The values obtained by the Polar Fitness Test® did not correlate well with direct measurement in ergospirometer (r = 0.1). CONCLUSION: The Polar Fitness Test® protocol is not valid to estimate O2max in physically active young men.