The forces acting on the boat are the drag force, stretcher force, pin force, buoyancy force, and the weight force. These forces determine the acceleration of the boat in three dimensions. Maintaining the highest and least variable boat velocity in the direction of progression is a goal of competitive rowing. The pin force is a major contributor to the net boat force especially during the drive phase and each of the propulsive, transverse and vertical pin forces have an effect on the instantaneous boat velocity. Oar handle force, usually the normal force, has been a regular target for measurement by researchers. While helpful information is available from recording the handle force, the longitudinal force on the oar is entirely neglected. Full decomposition of the oar force on the pin into the propulsive, transverse and vertical forces would provide a more complete picture of the effect of pin forces in all three directions. Sculling (1x) and Sweep oar rowing (2-) were examined. Three different stroke rates (20, 24, 28) were each tested over 500m. The 3-dimensional forces at both pins were measured with multi-component force transducers (Kistler). The angle of the oar was measured with a electrogoniometer. The data, which was telemetered (RowBot) to the laptop on the shore, was subsequently normalised and averaged to percent of stroke. The 3-dimensional pin forces allow us to separate out the propulsive force directly, which is needed to calculate the net propulsive force of the boat. Characteristics in the transverse force reflected the propulsive force although the magnitude of the ratio of these two forces was also a measure of the effectiveness of the stroke. Results indicate that the transverse forces pass 'neutral' at different points during the drive phase in sculling boats in comparison to sweep boats. There are also significant differences within the sweep boat between the two seats.
© Copyright 1999 5th IOC World Congress on Sport Sciences with the Annual Conference of Science and Medicine in Sport 1999. Alle Rechte vorbehalten.