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Biomechanical analysis requires the determination of specific foot contact events. This is typically achieved using force platform information; however, when force platforms are unavailable, alternative methods are necessary. A method was developed for the determination of gait events using an accelerometer mounted to the distal tibia, measuring axial accelerations. The aim of the investigation was to determine the efficacy of this method. Sixteen participants ran at 4.0 m/s ±5%. Synchronized tibial accelerations and vertical ground reaction forces were sampled at 1000 Hz as participants struck a force platform with their dominant foot. Events determined using the accelerometer, were compared with the corresponding events determined using the force platform. Mean errors of 1.68 and 5.46 ms for average and absolute errors were observed for heel strike and of –3.59 and 5.00 ms for toe-off. Mean and absolute errors of 5.18 and 11.47 ms were also found for the duration of the stance phase. Strong correlations (r = .96) were also observed between duration of stance obtained using the two different methods. The error values compare favorably to other alternative methods of predicting gait events. This suggests that shank-mounted accelerometers can be used to accurately and reliably detect gait events.

This study had two purposes: to evaluate a new method for measuring segmental dimensions for determining body segment inertial parameters (BSIP), and to evaluate the changes in mass distribution within a limb as a consequence of muscular contraction. BSIP were calculated by obtaining surface data points of the body under investigation using a sonic digitizer, interpolating them into a regular grid, and then using Green’s theorem which relates surface to volume integrals. Four skilled operators measured a test object; the error was approximately 2.5% and repeatability was 1.4% (coefficient of variation) in the determination of BSIP. Six operators took repeat measures on human lower legs; coefficients of variation were typically around 5%, and 3% for the more skilled operators. Location of the center of mass of the lower leg was found to move up 1.7 cm proximally when the triceps surae muscles went from a relaxed state to causing plantar flexion. The force during an impact associated with such motion of the soft tissue of the lower leg was estimated to be up to 300 N. In summary, a new repeatable and accurate method for determining BSIP has been developed, and has been used to evaluate body segment mass redistribution due to muscular contraction.

Guided by Self-Determination Theory (SDT), the present study examined the sport motivation and coping skills of male and female wheelchair basketball players with and without disability (N = 72). In line with SDT, results showed that intrinsic and extrinsic motivation as well as amotivation was found to be present in this sample of wheelchair basketball players. Results also demonstrated that the participants surveyed in the present study scored higher on self-determined types of motivation than non self-determined types of motivation, thus replicating past research with athletes without disability. Furthermore, wheelchair basketball players with and without disability did not differ significantly with respect to sport motivation and coping skills, suggesting that they are more alike than dissimilar. Finally, results revealed that self-determined motivation is associated with enhanced psychological functioning.

This phenomenological case study examined the leisure experiences of five women with intellectual disabilities (ages 44–60) in two group homes. Using participant observation, artifacts, and semistructured interviews, the nature of the women’s leisure experiences were understood within the conceptual framework of self-determination. Five staff members were also interviewed to further contextualize the women’s leisure experiences. Thematic analysis revealed three main themes: leisure at home, leisure in the community, and leisure with family and friends. Leisure was experienced differently in each group home, largely due to staff-created input into leisure choices. In one group home, leisure was supervised; in the other, independent leisure was encouraged. The study highlights the importance of promoting self-determined leisure for those approaching retirement age.

The utility of Deci and Ryan’s self-determination theory (1985) and Coakley’s unidimensional identity model (1992) has yet to be adequately assessed in understanding youth athlete burnout. This may be due to a lack of measures available to assess these relevant constructs in a youth athlete sample. Having such inventories would likely enhance practitioners’ ability to identify, prevent, and treat this phenomenon more effectively in young children. Therefore, the current study assessed the psychometric properties for modified burnout, motivation, and athletic identity inventories for a youth athlete sample. Participants included 88 youth swimmers ranging in age from 7 to 12 years, who completed measures assessing burnout, motivation, and athletic identity. Internal consistencies and exploratory factor analyses provided preliminary psychometric support for the use and continued evaluation of these revised measures with young athletes.