Comparison kinematic models of the traditional style deadlift are presented. Data was obtained through film and analyzed via computer and computer graphics. The comparison between the models revealed that the greater-skilled: 1. used less trunk flexion from the instant of initial trunk lean to the instant of maximum trunk lean, 2. used less knee extension (in same time interval as 1), and 3. demonstrated a smaller horizontal distance between the body center of mass (CM) and the CM of the bar at the instant the bar left the platform. A trend was also observed in which the greater-skilled subjects demonstrated less thoracic lean than the lesser-skilled group at the time the bar reached knee level.

This study investigated the self-concepts of five, six, and seven year old children after participation in organized and nonorganized play programs. The subjects were sixty boys and girls participating in Little League Tee-Ball programs and sixty boys and girls participating in the City Playground Program in the Fort Worth, Texas, area during the 1979 spring and summer season. The instrument used to measure self-concept was the Purdue Self-Concept Scale, Results indicated that the type of organization has little effect upon the self-concept of the children in this study.

The purpose of the study was to examine selected mechanical factors involved in hitting a baseball to the same and opposite fields. Special emphasis was placed on an identification of those factors which distinguish players of different hitting abilities. Twenty male college level baseball players, ten in each of two groups, hit six pitched baseballs, three each to two assigned areas of the playing field. The movement patterns for the opposite field and same field batting swings appeared to be similar in form with differences between the two swings due to (a) differences in the angular displacements at the left wrist and left elbow joints and (b) differences in the temporal characteristics.

Thirty trials of each of three roughness conditions were examined. The first condition consisted of a baseball pitched so that two of the roughness elements opposed the flow. The second condition consisted of a pitched baseball with four of the roughness elements opposing the flow. The third consisted of a pitched uniformly rough sphere. The conclusions were that roughness elements increase horizontal flight deviations when a baseball rotates about a vertical axis; roughness elements on the surface of a baseball may cause a decrease in the encountered drag forces; linear velocity has a dominating effect on the trajectory of a spinning baseball; previously developed mathematical models do not adequately predict flight deviations.