The structure of the force-energy domain of motor performance

This study was designed to delineate parameters of the force-energy domain of human motor performance. It involved the development of a theoretical model in which the hypothesized parameters of the force-energy domain were represented and a factor-analytic investigation of the hypothesized parameters within the theoretical model. The review of literature presented and discussed the development of factor-analytic strategies which were used in the statistical methodology portion of this study. In addition, factor-analytic findings related to the categories of strength and speed in the human motor performance domain were reported. The concept of force-energy in human movement defined in the context of classical physical mechanics provided theory supporting the need to investigate the interrelations between muscular strength and speed of body movement. The domain of force-energy vzas divided into two hypothesized categories; each category in turn was subdivided into dimensions as follows: I. Category I: Potential Force A. Isometric Leg Strength 1. Specific Isometric Leg Strength 2. General Isometric Leg Strength B. Body Composition 1. Positive 2. Negative II. Category II: Kinetic Energy A. Projection of Relative Body Mass 1. Acceleration of Relative Body Mass 2. Velocity of Relative Body Mass B. Projection of Absolute Resistance 1. Acceleration of Absolute Resistance 2. Velocity of Absolute Resistance The subjects for this study consisted of 68 male physical education majors at the University of Houston. Twenty-two experimental variables were selected to assess the domain of force-energy. Each variable measured a specific dimension of the domain, and moreover all dimensions were represented. Multiple trials of each test were administered in six test sessions for each subject during an eight-week time interval. Four different factor-analytic procedures; Alpha Factor Analysis, Canonical Factor Analysis, Truncated Principal Components Analysis, and Truncated Image Analysis were used to test the theoretical model posited for the force-energy domain. The solution delineated by each factoring procedure was orthogonally rotated to increase factor interpretability. Each orthogonal solution was subsequently relaxed through an oblique rotation procedure to enhance simple structure. Since several of the oblique factors were significantly intercorrelated, hierarchical factor analysis was employed to generalize across the primary dimensions to establish the higher order categories of the force-energy domain. Five of the hypothesized dimensions coincided with the six robust factors delineated in the primary solutions. These robust, primary factors were: (1) Specific Isometric Leg Strength, (2) Velocity of Relative Body Mass, (3) Acceleration of Absolute Resistance, (4) Velocity of Absolute Resistance, (5) First Phase Acceleration of Relative Body Mass, and (6) Second Phase Acceleration of Relative Body Mass. A tentative seventh factor, Second Specific Isometric Leg Strength, was also isolated. The hierarchical factor analysis yielded two factors coinciding with the hypothesized categories of the force-energy domain: (1) Potential Force and (2) Kinetic Energy. Five of the six primary factors supported the delineation of the potential force and kinetic energy categories. The dominant influence of the sixth primary factor, Second Phase Acceleration of Relative Body Mass, was probably neuromuscular coordination; a third potential category describing human motor performance.