Kleshnev V.V.
Saint-Petersburg Scientific-Research Institute For Physical Culture, St. Petersburg

Andreeva E.A.
Saint-Petersburg Scientific-Research Institute For Physical Culture, St. Petersburg
Lesgaft National State University of Physical Education, Sport and Health, Saint Petersburg

Objective of the study is to determine the basic theoretical principles, measurement methods and provide practical examples of the correct determination of the efficiency (COP) of an oar blade in rowing.
Methods and structure of the study. A telemetry system was used for the measurement, which allows you to accurately measure the efforts, angles of the oar and the movement of the boat, use this data to reconstruct the trajectory of the oar in the water during the stroke.
Results and conclusions. On average, during the stroke, the hydro-lift force provides about 56% of the total force on the blade, and the drag force provides the remaining 44%. The total drift of the blade center along its curved trajectory is 1.7 m, the total efficiency of the blade is 80.5%. The oar blade is a fairly efficient mover compared to 24% for the average physiological efficiency of the rower. Therefore, of all the metabolic energy consumed by the athlete, only less than 6% is lost to the drift of the blade, and the main part is dissipated as heat in the rower's body. The efficiency of the blade was higher at the beginning and at the end of the stroke, so it is advantageous to quickly build up the force after the catch and maintain it longer at the end, in other words, to make the force curve more rectangular. This is also beneficial for both the overall power and the efficient dynamics of the rowing system.

Keywords: academic rowing, mechanical efficiency, paddle efficiency.

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