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Background: The purpose of this study was to investigate the effects of a home-based muscle power training program on muscle strength and power, functional performance, and physical activity behavior in individuals at least 6 months posttotal knee arthroplasty. Methods: Twelve men and women, mean age 63.9 (6.8) and 6 months to 2 years posttotal knee arthroplasty unilateral or bilateral), completed this study. Participants were randomly assigned to the home-based power training intervention or step-monitoring comparison group. Quadriceps muscle strength and power, 6-minute walk test, functional leg power, and habitual walking behavior (average daily steps, minutes per week of moderate to vigorous physical activity) were assessed before and after intervention and then compared between and within groups. Results: The authors found no significant differences between the groups on amount of change in any of the outcomes, but mixed results on differences within each of the groups on the outcome measures. Conclusion: There were no differences between the groups for amount of change on the outcome measures the authors selected. Although within group differences varied slightly for each group, it was not enough to justify the more expensive home-based power training over the simpler step-monitoring intervention. [ABSTRACT FROM AUTHOR]

Background: Aerobic and muscle-strengthening activities are related to morbidities and mortality. Resistance exercise/strength training items are included in national surveys, but the manner in which muscle-strengthening activity is queried varies among these surveys. Purpose: The purpose of this study was to use different selfreport measures to examine the prevalence of meeting the 2008 Physical Activity Guidelines for Americans regarding muscle-strengthening activities among women. Methods: We surveyed 606 community-dwelling women at 4 points in time across a 1.5- to 3-year time period to determine whether the respondents met the national physical activity guidelines for performing muscle-strengthening activities ≥ 2 days per week. Results: Results were consistent across time but depended on the manner in which the question was asked. If asked to reflect over the past month or a general question about the typical number of days engaged, approximately 40% of women reported engaging in ≥ 2 days per week of resistance exercise/strength training. However, when reports were obtained weekly for 13 weeks, only approximately 18% of respondents met the guidelines. Conclusion: Results indicate that the timing and nature of questioning can substantially influence the selfreported prevalence of muscle-strengthening physical activities for community-dwelling women. [ABSTRACT FROM AUTHOR]

Context: The Star Excursion Balance Test (SEBT) is often used to train and assess dynamic balance and neuromuscular control. Few studies have examined hip- and thigh-muscle activation during the SEBT. Objective: To quantify hip- and thigh-muscle activity during the SEBT. Design: Repeated measures. Setting: Laboratory. Participants: 22 healthy individuals, 11 men and 11 women. Methods: EMG measurements were taken as participants completed 3 trials of the anterior (A), medial (M), and posteromedial (PM) reach directions of the SEBT. Main Outcome Measures: Mean EMG data (% maximal voluntary isometric contraction) from the gluteus medius (Gmed), gluteus maximus (Gmax), and vastus medialis (VM) were measured during the eccentric phase of each SEBT reach direction. Test-retest reliability of EMG data across the 3 trials in each direction was calculated. EMG data from each muscle were compared across the 3 reach directions. Results: Test-retest reliability ranged from ICC3,1 values of .91 to .99. A 2-way repeated-measure ANOVA revealed a significant interaction between muscle activation and reach direction. One-way ANOVAs showed no difference in GMed activity between the A and M directions. GMed activity in the A and M directions was greater than in the PM direction. There was no difference in GMax and VM activity across the 3 directions. Conclusion: GMed was recruited most effectively when reaching was performed in the A and M directions. The A, M, and PM directions elicited similar patterns of muscle recruitment for the GMax and VM. During all 3 SEBT directions, VM activation exceeded the 40-60% threshold suggested for strengthening effects. GMed activity also exceeded the threshold in the M direction. GMax activation, however, was below the 40% threshold for all 3 reach directions, suggesting that performing dynamic lower extremity reaching in the A, M, and PM directions may not elicit strengthening effects for the GMax. [ABSTRACT FROM AUTHOR]

Background: Self-report measures have been validated and are widely used. Interest currently lies in the development of simple, valid methods that can be used in any location to determine level of PA in large populations/samples. The purpose of this report is to illustrate tracking of physical activity behaviors and musculoskeletal injury reports on a weekly basis via the Internet. Methods: The Women's Injury Study (WIN) methodology includes use of BRFSS-related physical activity items that are completed online by more than 900 women weekly for an average of 3 years. Results: With more than 45,000 weekly physical activity and injury logs, the percentage of total logs submitted via online records is 91%. Self-reported pedometer steps are consistent with similar, smaller research samples. Conclusions: This report suggests that Internet tracking is a viable means of assessing nearly real-time physical activity, describes the process of developing and monitoring self-reported physical activity behaviors via the Internet, and provides recommendations for others considering such methods. [ABSTRACT FROM AUTHOR]

Background: Effect of muscle strength and balance on falls has not been well researched in healthy older women. The purpose of this study was to compare lower extremity strength and balance in older healthy women during each decade of life and to investigate which factors are different in women with a history of falling. Methods: We retrospectively studied 240 women age 50-89 y. Measures of muscle strength, postural stability, and incidence of falls over the past year were obtained from client charts at Texas Woman's University's Health Promotion & Research Center from 1996 to 2002. Results: Strength declined signify scantly with age in all muscle groups except knee extensors. Age, hip flexor and abductor strength, and postural stability were signify scantly different in women who had fallen. Conclusions: Strength decline was not consistent across muscle groups. Women who were older, had less hip flexor or abductor strength, or less balance were more likely to have fallen. [ABSTRACT FROM AUTHOR]