A new instrumentation system for training rowers

Abstract

A dry-land rowing system was developed to provide the coach and/or athlete with quantitative information about the athlete's kinetics and kinematics while the athlete trains. This system consists of a Concept II rowing ergometer instrumented with a force transducer and potentiometer, four electrogoniometers attached to the athlete's ankle, knee, hip, and elbow, and a data acquisition computer. The force transducer is used to quantify the athlete's pulling force. The potentiometer signal is used to locate the position of the handle. The electrogoniometers provide signals proportional to joint angles. A link segment model of the human body is used to locate joint centers based on limb lengths and joint angles. The computer is used to collect and process all the transducer signals, perform the link segment calculations and provide feedback to the coach or athlete in the form of a stick figure animation overlaid with kinematic and kinetic information. This system allows the coach and athlete to quickly study a rower's mechanics, to evaluate the effects that technique changes have on the power produced by the athlete, and to identify technique differences between athletes.

Introduction

Competitive rowing is an extremely technical and physically demanding activity. The task of propelling a racing shell across a given distance of water as fast as possible involves the interaction between physical strength, endurance, technical skill of the athlete, and the design of the shell/oar system. A potentially valuable tool for training both novice and elite rowers is a feedback system that provides the athlete with quantitative information about his/her rowing mechanics and the instantaneous power developed throughout a stroke as he/she rows.

Though the technology is available to construct a training tool of the type described above, the literature does not suggest that such a device exists. Researchers have studied physiological aspects of rowing (Di Prampero et al., 1971; Hagerman et al., 1978; Hagerman, 1984), movement kinematics and kinetics during rowing (Bompa, 1980; Martin and Bernfield, 1980; Struble et al., 1981; Schneider and Hauser, 1981; Asami et al., 1981; Nelson and Widule, 1983; Deming et al., 1988; Hartmann et al., 1993; Roth et al., 1993; Pudlo et al., 1996; MacFarlane et al., 1997), and boat/oar loading (Celentano et al., 1974; Deming et al., 1988; Roth et al., 1993). Typically these studies involve considerable lag time between the data collection, data processing and analysis, and finally the presentation of the findings to the coach or athlete. This lag time limits the coach's effectiveness in using the information to modify technique and evaluate the impact these modifications have on performance.

The objective of this study was to construct a dry-land rowing system that provides immediate feedback about the rower's joint kinematics, pulling force and pulling power. The unique feature of this system is its ability to provide immediate feedback on both human movement characteristics and the force and power delivered to the rowing handle throughout a rowing stroke. This feature allows the coach and athlete to quickly identify movement strategies that maximize propulsive power. Further, the feedback information can be compared between rowers and used to assist coaches in team selection.