This study aimed to clarify the influence of a smaller goal used for children's water polo games in 2010 on total shot, score and shot success rate. Data obtained from three games using standard (spring 2009) and smaller goals (summer 2010 and spring 2011) were analyzed.
  Results were as follows;
1) The total score for the spring 2009 game was significantly higher than the summer 2010 game (p<0.05).
2) The total shot success rate for the spring 2009 game was significantly higher than the summer 2010 (p<0.05) and spring 2011 (p<0.05) games.
3) Middle shots occurred significantly more frequently in the spring 2011 game than the summer 2010 game (p<0.05) because direct shots from outside the 5 m line were permitted by the 2011 rules.
4)  Counter attack shots and goals occurred significantly more frequently in the spring 2009 game than the summer 2010 game (p<0.05).
  These results indicate that shooters should adapt to the smaller goal early.

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Kicking like a propeller in breaststroke is nowadays widely used by breaststrokers. Maglischo⁵⁾ explains that a breaststroker kicks until legs are stretched straightly to generate thrust, drawing a semicircle with both legs like a propeller. It is said that the breaststroke kick like the propeller is supposed to generate big thrust. But in the process of this study, the calculation result of propeller-like kick thrust revealed that enough thrust does not occur in the usual propeller theory. It seems that the application of Dynamic Stall is to be supposed to generate enough thrust to apply the second law of Newton. The purpose of this study is to obtain the method for the analysis of this big thrust using Dynamic Stall.

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The purpose of this study was to find out the physiological response difference of long-distance (LDS) and sprint swimmers (SPS) to intermittent swimming test at critical swimming velocity (CV) in swimming flume. First, twelve trained swimmers (LDS, n=6; SPS, n=6) swam at five swimming speeds with maximal effort to determine the CV. Then, ventilation (VE), oxygen consumption (VO₂), heart rate (HR), blood lactate concentration (BLa), respiratory exchange ratio (R) and relative oxygen consumption (%VO_2max) were examined during intermittent swimming test at CV. For the LDS, only HR increased significantly during intermittent swimming test. For the SPS, significant increases in VE, VO₂, HR, and %VO_2max were observed. In the comparison between the two groups, VE, VO₂, HR, BLa and R were significantly higher in the LDS at all repetitions. Thus, intermittent swimming at CV induces constant physiological intensity in the LDS and gradually increases physiological intensity in the SPS, and there were clear differences in physiological responses between LDS and SPS.

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