Comparison of lower body specific resistance training on the hamstring to quadriceps strength ratios in men and women.

In this study, we compared hamstring (H) and quadriceps (Q) strength changes in men and women, as well as changes in conventional and functional H:Q ratios following an identical 12-week resistance training program. An isokinetic dynamometer was used to assess 14 male and 14 female participants before and after the intervention, and conventional and functional H:Q ratios were calculated. Hamstring strength improved similarly in men and women, but improvement in quadriceps strength was significantly greater in men, while women showed only modest improvements. For the conventional and functional H:Q ratios, women showed significantly greater improvements than men. Both men and women were able to exceed the commonly recommended 0.6 conventional and 1.0 functional H:Q ratios after the 12-week lower-body resistance training program.

Comparison of longitudinal biomechanical adaptation to shoe degradation between the dominant and non-dominant legs during running.

This study compared the biomechanical adaptation to running shoe degradation between the dominant (D) and non-dominant (ND) leg. Twenty-four runners performed a pre-test in the laboratory, completed 200 miles of road running in a pair of assigned shoes and then returned for a post-test. Kinetic and kinematic data of running in new and worn shoes were collected. Repeated measures ANOVA (Shoe×Leg) were used to analyze temporal, kinetic and kinematic variables (α=.05). A symmetry index (SI) was calculated for the temporal and kinetic variables and paired t-tests were used to compare the SI between shoe conditions. Stance time increased by approximately 7 ms in worn shoes (p=.027). Bilateral differences in the kinematic change (Shoe×Leg interaction) were seen in the torso (p<.05), knee (p<.05), marginally at the hip (p<.10) but not the ankle. No difference in kinetic variables or SI was observed. When running in worn shoes, the torso displayed reduced forward lean for both sides and to a greater extent during the D leg strike. The D hip and knee showed a more extended position for the worn shoe condition while an increased flexion was observed in the ND leg. Most of the kinematic differences observed were small and within the intra-subject variability measured during the same session. Future studies may consider performing a three-dimensional analysis at a higher sample rate and further explore whether asymmetrical adaptation is related to running injuries.

Correlation of three different knee joint position sense measures.

OBJECTIVE: The purpose of this study was to investigate correlation during concurrent measurement among three knee joint position sense (JPS) measures in sitting position and between two measures in standing position. METHODS: Isokinetic dynamometer, electrogoniometer, and two dimensional (2D) video analysis were used for measuring knee JPS. The JPS was measured both in sitting and standing positions. All three measures were employed concurrently to measure knee JPS in sitting position; however, only the electrogoniometer and 2D video analysis were concurrently used in the standing position. The knee JPS was recorded in sitting position at 15 degrees, 30 degrees, and 45 degrees and in standing at high, mid and low knee flexion positions. RESULTS: The results of the study suggest excellent correlation (0.94-0.98) between the electrogoniometer and 2D video analysis measures in standing position. In sitting position, good to excellent correlation (0.63-0.92) was found between the isokinetic dynamometer and electrogoniometer; however, fair to good correlation was found between 2D video analysis and either of the two measures (electrogoniometer [0.52-0.57] and isokinetic dynamometer [0.41-0.63]. CONCLUSION: Either 2D video or an electrogoniometer may be used to measure JPS in standing position; however, in sitting position 2D video should not be used if the camera is required to be placed at 10 degrees from the plane of motion.

A comparison of knee joint laxity among male and female collegiate soccer players and non-athletes.

Female athletes are at least twice as likely to sustain an anterior cruciate ligament injury than male athletes. The underlying cause of ACL injury is multifactorial. However, several researchers have identified knee joint laxity as a possible contributing factor. The purpose of this study was to provide a comparison of knee joint laxity between male and female collegiate soccer players and male and female non-athletes. Thirty-nine (19 male, 20 female) apparently healthy, collegiate athletes from the University of Texas at El Paso's 2001-2002 women's intercollegiate soccer team and men's club soccer team, and forty (20 male, 20 female) non-athletic students volunteered to participate. All participants were tested bilaterally using the KT-1000 MEDmetric knee joint ligament arthrometer. Three tests were used to determine anterior laxity: passive displacement, active displacement, and the Lachman test. The mean passive displacement, mean active displacement, and Lachman (only for the left leg) were significantly lower for the athletic group than for the non-athletic group. There were no significant differences found between males and females for the passive and active drawer tests. However, females had significantly more laxity than males in the Lachman test. These findings suggest that strength and conditioning may play a more significant role in knee joint laxity than the sex of the individual.