The effects of selected body positions on water resistance have been studied in previous experiments, using a series of existing standardized relationships from ship building model research (Clarys et al., 1974). Form is an important factor influencing resistance, but body position changes must also be considered as factors that increase or decrease resistance. Karpovich (1933) and Schramm (I 958-1959) reported that the supine streamlined position offered more resistance than a prone position. Hairabedian (1964), Schramm (1958-1959), Clarys et al. (1973), and De Goede et al. (1971) showed that resistance increased considerably when lifting the head out of the water from a streamlined prone glide. Total resistance also increases as the angle of inclination of the body to the water surface increases, especially at low velocities (Karpovich, 1933; Alley, 1952; Clarys et al., 1974). Ln their research, Kent and Atha (1971) showed that greater resistance is created in four transient breaststroke body positions than in the glide position. Finally, Counsilman (1955), who examined the total drag of prone and side positions, stated that "less resistance is created in the prone than in the side position because the flow of the water against his feet tended to lift them and to streamline the body to a greater extent. The waterflow when the subject was being towed on his side did not elevate his feet as much, and consequently, the body was not as streamlined." In all these studies a significant increase of total resistance was reported for all body positions (orientations) when compared with the glide or prone position. All experiments were carried out using a towing device consisting of an electromotor, a pulley system, a tow line, dynamometer (spring scale and strain gauges), and transducer systems with kymograph or galvanometer recordings. This study examined experimentally the total resistance (or drag) associated with two selected front crawl body positions at five different velocities. The validity of the results obtained during towing has been shown to be a function of the resistance as described in previous studies. This study also sought to establish resistance values at selected speeds for the side position. Comparison is also made with data reported by Counsilman (1955).
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