Recently, there are many cutter races held in many places. But their rowing method are each different based on their experiment method of each team. So, there is little study of evaluation for this sport. In this study, we aimed to clarify some features actually seen in the winning teams by quantifying and comparing of the boat speed or turning situations for the good prize in the cutter race. At the 62nd All Japan Cutter Race (total number of 12 teams) held in May 2018, a portable GPS terminal was attached to the bow of each total four 9-meter-long cutter boats, and the recorded the position data by every second. In this study, races are classified into three parts such as start dash (hereinafter "SD"), turning head and cruises. The boats speed, under water ratio of oar during cruising, and required time for SD are evaluated. As a result, SD has smallest time difference between teams and maximum time difference was 6 seconds. The turn can be divided into three groups from the total amount of course change value, boats speed or track pattern. Furthermore, cruise is most important as accounts for more than 80% of the total race, and there was positive correlation between the underwater ratio and the average boats speed during cruise.

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To increase boat speed during cutter races, improving the rowing efficiency of oars is important. To clarify the characteristics of rowing cutters, total 17 patterns rowing experiments were carried out at Togitsu Port in Omura Bay, Nagasaki Prefecture. At this experiments, total 6 scullers rowing power were measured and estimated total rowing power or rowing efficiency with changing scullers positions, respectively. Moreover,the boat speed was also recorded using a portable GPS device. Experimental results showed a difference of more than twice the rowing power was observed when the rowing position was changed even with the same rower, showing strengths and weaknesses. However, no correlation was observed between a subject’s average rowing power and their physique (height, weight, body fat mass, muscle mass, BMI, and FFMI). Furthermore, the rowing power may be attributed to factors other than physique. The average mean total rowing efficiency was 25.7% ± 2.1% (± S.D.) during headwinds. Even when the members are together, the rowing efficiency showed a difference of more than 7%, simply because the scullers were arranged in different positions. The rowing power and technical factors were suggested to be important factors influencing the rowing efficiency.

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In the present study we experimented man's pulling force on oarsmanship by a human power and evaluated its quantity for the new face of Cutter-crew of 6 universities in west Japan in October 1996. The experiment of "the basis pulling" means a pair of crewmen sitting on the No.7th and No.8th sheets with powerful rowing named "Tan-riki" was carried out by 2 preparing connection oars with distortion gauges. Meantime, other 5 pairs should be with no rowing. These experiments were carried out six times by every pair in turn. And also "the whole pulling", which means 12 crewmen rowing with "Tan-riki" and "the dash pulling", means 12 crewmen rowing with a hypothesis of the most powerful rowing for a race same as before a pair of the No.7th and No.8th crewmen were recorded for each university. All the experiments were held at Togitsu port in Omura-Bay during still water. We measured the area of output wave-like by analogue data records and calculated man's pulling force(kgf/s) for each univertity. The result was as follows : 1) The output wave-like analogue data record shows the characteristic of the oarsmanship of each university. 2) "The basis pulling" at the 12 crewmen from No.1 to No.12 of each university was calculated. The mean values were from 8.5 to 11.6kgf and their standard deviations were from 1.06 to 1.61kgf. 3) Basing on "the basis pulling", output ratios of the No. 7th and No. 8th crewmen of each university of "the whole pulling", and "the dash pulling" were calculated out. The order of the output ratios had a high correlation to the race result. 4) Race speed of the boat during still water was from 5.0 to 5.7 knots. They were corresponded to the total resistance from 33.0 to 43.6kgf (displacement of boat in 2, 700kgf) by the towing test. Consequently, effective horsepower of each university became from 1.1 to 1.7ps. We also quantitatively estimated the indicated horsepower of a crew, which was about from 0.29 to 0.43ps according to the position of grip, rowlock as well as blade of an oar.

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