The effects of obesity classification method on select kinematic gait variables in adult females.

AIM: Obesity has been associated with gait alterations, but most studies have utilized BMI for classification. This study examined gait alterations based on body fat and BMI. METHOD: Participants (N.=22) had BMI and body fat percentage determined and underwent gait analysis. Body fat percentage was determined using dual energy x-ray absorptiometry (DEXA). Gait variables were examined in 3 groups: step width, preferred walking speed, and stride length; angular displacement at the knee and angular displacement at the ankle; and peak knee flexion velocity and peak knee extension velocity. A multivariate approach with follow-up univariate tests was used. RESULTS: Based on BMI, there was a significant effect for step width, preferred walking speed, and stride length (F[3, 16]=3.47, P=0.04). Univariate tests were significant for preferred walking speed and stride length (both P<0.03). Overweight by BMI participants had a lower preferred walking speed (1.31±0.16 m/s vs. 1.53±0.18 m/s) and shorter stride length (1.23±0.11 m vs. 1.38±0.11 m). Based on body fat percentage, there was a significant effect for peak knee flexion velocity and peak knee extension velocity (F[2, 19]=4.08, P=0.03). Overweight by body fat participants had lower peak knee flexion velocity (295.99±21.32 o/s vs. 320.25±27.67 o/s; P=0.04). CONCLUSION: Gait alterations were found for both methods of classifying obesity. However, the alterations were different for each method. The method of determining obesity appears to affect where gait alterations are found.

The effects of power and strength training on bone mineral density in premenopausal women.

AIM: The purpose of this 48-week exercise intervention was designed to examine the effects of power and resistance training on bone mineral density (BMD). METHODS: Premenopausal women were recruited and randomly assigned to either a power (N.=8) or resistance (N.=11) training group. The power exercises included jumping rope, skipping, hopping, and other power-type exercises. The resistance training group performed 8-10 whole-body strengthening exercises at 70% one-repetition maximum (1RM). Before and after the exercise intervention, BMD was measured via dual energy x-ray absorptiometry (DXA) for the total-body, lumbar spine, left femoral neck, and left greater trochanter. Muscular strength was measured by hand grip dynamometer and 1RM of chest press and leg press. Muscular power was assessed by the Margaria-Kalamen stair climb test. Data were analyzed using repeated measures ANOVA. RESULTS: There were no statistical differences between the two training groups for any of the BMD measurements. Chest press strength was different between the two groups, increasing 6.41 and 1.1kg for the resistance and power groups, respectively over the course of the training period (F[1.15]=9.44, P<0.01). There was a significant time effect for leg press 1RM (F[1.15]=6.04, P=0.03). The participants increased by 12.37kg after the 48-week intervention. Hand grip strength also increased after the study intervention (F[1.16]=46.32, P<0.01). CONCLUSION: The results of this study suggest that power and resistance training are comparable techniques for maintaining bone density.

Physical and emotional abuse and motor development: a preliminary investigation.

Mothers of 212 children aged 2 to 12 yr. responded to a problem checklist. Significantly more children reported as maltreated were said to have learning difficulties than comparison children; language delays and poor motor coordination were also noted. Such children would benefit from the formal assessment and remediation of problems in motor development.