The purpose of this study was to quantify and contrast the instantaneous segmental and total body energy patterns of rowing a single scull racing shell with rowing a Gjessing (Norway) rowing ergometer (RE), and to contrast energy savings through exchanges of mechanical energy among segments and conversions of energy within segments. Four scullers, two male and two female, were filmed at three stroke rates while rowing on a stationary and a wheeled RE, and rowing in single sculls racing shells. Coordinates of joint markers were digitized, digitally filtered, and combined with estimated body segment parameters using link-segment mechanics to obtain segmental centre of gravity kinematics. Mechanical energy and internal work analyses were conducted to compute the energy savings due to exchange and interconversion of segmental energy. The internal work was least in the wheeled RE and greatest in the boat. Savings of energy through exchanges were greatest in the boat, and least in the stationary RE. Savings of energy through interconversion were greatest in the wheeled RE. The interconversions (expressed as a percentage of total work) were quite similar for both the boat and the stationary RE. The additional energy savings with the wheeled RE allow the conclusion that wheeled RE testing will permit athletes to work at stroke rates similar to racing levels.
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