Resumo em Inglês:

The aim of this study was to verify validity and reliability of the scores for physical exercise in leisure (PEL), leisure and locomotion activities (LLA), and total score (TS) of the Baecke habitual physical activity questionnaire in adult males. Twenty-one students of Physical Education were evaluated. For validation, the maximum oxygen uptake (<IMG SRC="/img/revistas/rbme/v9n3/17260s01.gif" WIDTH=10 HEIGHT=12>O2max) and the decrease of the heart rate in percentile (%DHR) were measured through the Cooper's 12-minute walk or run test, and an annual index of physical exercise (IPE), and a week index of locomotion activities (ILA). The reliability was verified through test-retest with interval of 45 days. The Pearson correlation coefficient, and partial correlation adjusted for age and body mass index were used for validation. The intraclass correlation and paired t-test were used for reliability. The results indicated that %DHR was correlated with LLA and TS (r = 0.47 and p = 0.030; r = 0.48 and p = 0.027, respectively). IPE was correlated with PEL and TS (r = 0.56 and p = 0.008; r = 0.46 and p = 0.036, respectively). ILA was correlated with LLA and TS (r = 0.64 and p = 0.002 and r = 0.51 and p = 0.017, respectively). There was no significant difference in PEL, LLA and TS means in test-retest. The intraclass correlations were r = 0.69; r = 0.80 and r = 0.77, respectively for PEL, LLA and TS. In conclusion, the Baecke questionnaire is valid and reliable to measure habitual physical activity in Brazilian adult men.

Resumo em Inglês:

OBJECTIVE: The aim of the present study is to compare the values of the maximal oxygen uptake (<IMG SRC="/img/revistas/rbme/v9n3/17260s01.gif" WIDTH=10 HEIGHT=12>O2 max) during two consecutive bouts in Wingate tests for arms and legs in swimmers (S) and water polo players (WP). METHODS: Sample - seven national level athletes (4 S and 3 WP), age 17,90 ± 2,14 years, body mass 71,41 ± 6,84 kg, height 176,65 ± 7,02 cm, % body fat 13,23 ± 4,18. Two Wingate bouts with 30 sec each with 3 min interval between them, for arms and legs in alternated days. Oxygen uptake: breath-by-breath using the gas analysis system K4 b² Cosmed. Statistical analysis: Wilcoxon test for dependent variables and Kolmogorov-Smirnov test for independent variables. RESULTS: The mean values found at the <IMG SRC="/img/revistas/rbme/v9n3/17260s01.gif" WIDTH=10 HEIGHT=12>O2 peak (P<IMG SRC="/img/revistas/rbme/v9n3/17260s01.gif" WIDTH=10 HEIGHT=12>O2), mean power (MP) and peak power (PP) for each bout of the Wingate test, for arms and legs. For Arms: P<IMG SRC="/img/revistas/rbme/v9n3/17260s01.gif" WIDTH=10 HEIGHT=12>O2 = 55.16 ± 5.72 ml.kg-1.min-1, MP = 5.28 ± 0.59 watts.kg-1 and PP = 6.71 ± 0.88 watts.kg-1 got in the first bout (1st Arms) and P<IMG SRC="/img/revistas/rbme/v9n3/17260s01.gif" WIDTH=10 HEIGHT=12>O2 = 60.12 ± 6.10 ml.kg-1.min-1, MP = 5.03 ± 0.40 watts.kg-1 and PP = 6.25 ± 0.51 watts.kg-1, got in the second bout (2nd Arms). For legs: P<IMG SRC="/img/revistas/rbme/v9n3/17260s01.gif" WIDTH=10 HEIGHT=12>O2 = 55.66 ± 6.85 ml.kg-1.min-1, MP = 4.75 ± 1.79 watts.kg-1 and PP = 7.44 ± 1.96 watts.kg-1 got in the first bout (1st Legs) and P<IMG SRC="/img/revistas/rbme/v9n3/17260s01.gif" WIDTH=10 HEIGHT=12>O2 = 62.09 ± 5.99 ml.kg-1.min-1, MP = 4.28 ± 1.47 watts.kg-1 and PP = 6.68 ± 1.63 watts.kg-1 got in the second bout (2nd Legs). DISCUSSION AND CONCLUSION: All variables studied did not present significant difference among arms and legs, as much the first as the second bout for arms for P<IMG SRC="/img/revistas/rbme/v9n3/17260s01.gif" WIDTH=10 HEIGHT=12>O2 (p < 0.05). There was no difference between the PM mean values of the first and the second bout. But the mean of the second bout of legs was significant smaller than the first bout (p < 0.05). For the PP variable there was no difference among the mean values to the first and second bout as much for arms as for legs. It looks like to exist larger magnitude to O2 adjustment for arms than legs, that could be associated to specific demands to which S and WP athletes are daily submitted in their trainings.

Resumo em Inglês:

With the advances in the studies of body composition, it has been observed that several factors can interfere with the estimates of relative body fat using the skinfold thicknesses method. Therefore, the purpose of this study was to investigate the impact of the use of different skinfold calipers for the analysis of body composition by skinfold thicknesses measurements. Two hundred and fifty nine male subjects (23.3 ± 2.9 years) took part of the study. Nine skinfold thicknesses were measured (abdominal, subscapular, suprailiac, triceps, biceps, midaxillary, chest, medial calf, and thigh) using the Lange (USA) and the Cescorf (Brazil) calipers with accuracy of 1.0 and 0.1 mm, respectively. Significant differences were found in the comparison between the two calipers on all the investigated skinfold thicknesses (1.8 to 31.0%) with highest values obtained by the Lange caliper (p < 0.01). When these values were applied to four different predictive equations, developed by different researchers, the body fat estimate was significantly modified (p < 0.01), resulting in differences of 5.2 to 6.9%. Results indicate that the use of different skinfold calipers may maximize the errors of estimation produced by different predictive equations used for the analysis of body composition.

Resumo em Inglês:

Because of the medium chain triglycerides (MCT) specific physical and chemical properties, they have been used over the last 40 years in enteral and parenteral nutrition. Results from clinical practice lead some researchers in the early 80's to use them for ergogenics purposes. The hypothesis was based on the relationship between the oxidation rates of carbohydrate and fat. The increase in fat oxidation would promote glycogen sparing effect, and therefore, delay the time to exhaustion. The aim of the present paper is to review the effects of MCT supplementation upon endurance exercise performance. Most of the studies failed to prove the ergogenic effect of MCT. A few studies that showed the ergogenic effect of MCT administration used alternative experimental designs, such as high MCT dose (above from the previous established limit) or infusion. The chronic use of MCT by athletes is new and few studies have been done in this matter. These few studies showed controversial results. There is a strong tendency in the literature that MCT is not a viable strategy to increase performance during endurance exercise. The aim of this study is to discuss the effects of MCT use on endurance exercise.

Resumo em Inglês:

Erythropoietin is an endogenous hormone of glicoproteic nature secreted by the kidneys and is the main regulator of the erythropoiesis. An alteration in its production generates a disturbance in the plasmatic concentration giving rise to several types of pathologies related to the hematopoietic system. The recombinant forms of erythropoietin have indiscriminately been used by athletes, mainly in endurance sports, by increasing the erythrocytes concentration, generating a better delivery of oxygen to the muscle tissue. The administration of recombinant erythropoietin was prohibited by the International Olympic Committee and its use considered as doping. This review has the intention to describe the physical, biological and pharmacokinetic properties of the endogenous erythropoietin, as well as its recombinant form, describing also its use in sports and the process of searching methodologies for its detection in doping control.