Analysis of Knee Mechanics during the Squat Exercise: Differences between Females and Males

of Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements of the Degree of Master of Science. ANALYSIS OF KNEE MECHANICS DURING THE SQUAT EXERCISE: DIFFERENCES BETWEEN FEMALES AND MALES By Francis Arlington Forde May 2005 Chairman: John Chow Major Department: Applied Physiology and Kinesiology The purpose of this study was to analyze the differences in tibiofemoral joint mechanics between males and females during squatting using the Trapezoid bar (TB) and Straight bar (SB). Twenty-two subjects were recruited from the University of Florida. Each subject performed two randomly assigned squat tests, one using a straight bar and the other using a trapezoid bar. Each test consisted of two trials with each trial consisting of three repetitions. Video, force platform and EMG were used to collect kinetic, kinematic and muscle activity data. MANOVA results for the EMG data found significant differences for Quadriceps activity between the TB and SB squat conditions with the TB resulting in higher quadriceps muscle activation. Significant differences were also found between the ascending and descending phases of the squat for gluteal and hamstring muscle activity. The ascending phase resulted in higher muscle activation than the descending phase. The MANOVA also revealed significant interactions between phase and gender for gluteal