This study was undertaken to determine the metabolic and cardiorespiratory differences between treadmill running, ergometer cycling and roller skating in top level roller skaters. The subjects performed 3 discontinuous graded tests until exhaustion. The protocol was established so that heart rate kinetics during exercise were similar in all the tests. Maximal oxygen uptake (VO2max), maximal heart rate and exercise time to exhaustion were higher during running (p < 0.05) than during cycling. Blood lactate during submaximal and maximal running exercise was significantly lower (p < 0.05) than during cycling or roller skating. There were no differences between cycling and roller skating in any of the variables studied. These results seem to suggest that, compared with running, VO2max during cycling is limited more by local muscle fatigue than by cardiac factors. The similar response found during roller skating and cycling supports the concept that cycloergometer testing is a valid simple laboratory test for testing physical fitness in top level roller skaters.

Purpose. To compare the performance in the execution of specific motor skills among novice futsal players in 3 competitive categories (U-7, U-9, and U-11) and to compare their performance in specific motor skills during the offensive and defensive phases of the game. Methods. Ten specific motor skills were investigated, including 6 offensive actions and 4 defensive actions, in 49 futsal players aged 6-11 years. Technical performance was analysed in terms of the number of actions, the effectiveness of the action (successful or unsuccessful), and where the action occurred (offensive or defensive midfield). One-way ANOVA was used with the Tukey test, when appropriate, or Student's t-test, with a significance level of 5%. Results. Players in the older categories were more effective defensively than those in the younger categories (F 2,46 = 6.04, p < 0.01, partial 2 = 0.21). The two older groups had an approximately two-and three-fold greater chance, respectively, of executing successful defensive technical actions (OR = 1.82, p < 0.05; OR = 2.83, p < 0.01). Furthermore, the players were more technically effective in the offensive phase of the game than in the defensive phase (M = 41.35, SD = 21.53 and M = 16.47, SD = 7.90, respectively; t 96 = 7.60, p < 0.01, d = 1.69). Conclusions. Players in older competitive categories were more effective, and players were more effective offensively than defensively.