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Brian M. Wood, Herman Pontzer, Jacob A. Harris, Audax Z.P. Mabulla, Marc T. Hamilton, Theodore W. Zderic, Bret A. Beheim and David A. Raichlen
The rapid adoption of lightweight activity tracking sensors demonstrates that precise measures of physical activity hold great value for a wide variety of applications. The corresponding growth of physical activity data creates an urgent need for methods to integrate such data. In this paper, we demonstrate methods for 1) synchronizing accelerometer and Global Positioning System (GPS) data with optimal corrections for device-related time drift, and 2) producing principled estimates of step counts from GPS data. These methods improve the accuracy of time-resolved physical activity measures and permit pedestrian travel from either sensor to be expressed in terms of a common currency, step counts. We show that sensor-based estimates of step length correspond well with expectations based on independent measures, and functional relationships between step length, height, and movement speed expected from biomechanical models. Using 123 person-days of data in which Hadza hunter-gatherers wore both GPS devices and accelerometers, we find that GPS-based estimates of daily step counts have a good correspondence with accelerometer-recorded values. A multivariate linear model predicting daily step counts from distance walked, mean movement speed, and height has an R 2 value of 0.96 and a mean absolute percent error of 16.8% (mean absolute error = 1,354 steps; mean steps per day = 15,800; n = 123). To best represent step count estimation error, we fit a Bayesian model and plot the distributions of step count estimates it generates. Our methods more accurately situate accelerometer-based measures of physical activity in space and time, and provide new avenues for comparative research in biomechanics and human movement ecology.
Xiaofen D. Keating, Jingwen Liu, Xiaolu Liu, Jeff Colburn, Jianmin Guan and Ke Zhou
Purpose: This study investigated beliefs about the physical education (PE) profession of Chinese preservice physical education teachers (PPETs). Methods: Chinese PPETs (N = 660) from six universities participated in the study. Data were collected using a prevalidated survey—a scale of measuring Chinese PPETs’ beliefs about the PE profession, which consists of two domains: a sense of calling and the value of the PE profession. Analysis of variance and multivariate analysis of variance were used to examine the differences in overall beliefs and the two subdomains by gender and year in college, respectively. Results: The overall beliefs were positive. The sense of calling and value of the PE profession varied significantly by the year in college. Senior students had the lowest score in value of the PE profession, whereas sophomores showed the lowest score in sense of calling. Conclusions: PE teacher education programs had limited effects on changing Chinese PPET beliefs about the PE profession.
Tan Leng Goh and Kristin Scrabis-Fletcher
Purpose: Physical education teacher education programs prepare preservice teachers to lead Comprehensive School Physical Activity Programs. Through the coordination of a university’s physical education teacher education program and an elementary school, the purpose of this study was to examine preservice and in-service teachers’ perspectives in implementing a 6-week movement integration program. Method: A total of 12 preservice teachers participated in a weekly online discussion forum as part of a community of practice. In addition, the preservice teachers and three in-service teachers participated in an interview. Data were analyzed for themes. Results: The themes were facilitating implementation through support, sharing ideas for common practice, and overcoming challenges in implementation. Support received by the preservice teachers facilitated the implementation of the program. They also shared strategies to overcome implementation challenges through the weekly online discussions. Discussion/Conclusion: Fostering communities of practice among preservice teachers prepares them for collaboration and movement integration implementation in the future.
Aviroop Dutt-Mazumder, Richard L. Segal and Aiko K. Thompson
This study investigated effects of ankle joint angle on the Hoffman’s reflex (H-reflex) excitability during loaded (weight borne with both legs) and unloaded (full body weight borne with the contralateral leg) standing in people without neurological injuries. Soleus H-reflex/M-wave recruitment curves were examined during upright standing on three different slopes that imposed plantar flexion (−15°), dorsiflexion (+15°), and neutral (0°) angles at the ankle, with the test leg loaded and unloaded. With the leg loaded and unloaded, maximum H-reflex/maximum M-wave ratio of −15° was significantly larger than those of 0° and +15° conditions. The maximum H-reflex/maximum M-wave ratios were 51%, 43%, and 41% with loaded and 56%, 46%, and 44% with unloaded for −15°, 0°, and +15° slope conditions, respectively. Thus, limb loading/unloading had limited impact on the extent of influence that ankle angles exert on the H-reflex excitability. This suggests that task-dependent central nervous system control of reflex excitability may regulate the influence of sensory input on the spinal reflex during standing.
Damien Whitburn, Adam Karg and Paul Turner
Relationship marketing through digital forms of integrated marketing communications can provide sport organizations with a range of positive outcomes. Given decreasing participation, membership and funding pressures, sport organizations need to engage with current and prospective consumers to alleviate these concerns. Drawing on existing research in the digital communications setting, a framework illustrating the end to end integrated marketing communications function as implemented by governing bodies as a form of not-for-profit sporting organizations is presented and tested. Satisfaction with integrated marketing communications was shown to have a direct effect on relationship quality and behavioral intentions, including revenue raising, increasing participation, raising awareness, and enhancing public perception providing practical and theoretical benefits.
Wyatt D. Ihmels, Kayla D. Seymore and Tyler N. Brown
Context: Conventional ankle prophylactics restrict harmful ankle inversion motions that lead to injury. But these existing prophylactics also limit other ankle motions, potentially leading to detriments in functional joint capacity. The ankle roll guard (ARG) may alleviate the prevailing issues of existing ankle prophylactics and prevent harmful ankle inversion, while allowing other joint motions. Objective: This technical report sought to compare the ARG’s ability to prevent ankle inversion, but not restrict other ankle motions with existing prophylactics. Design: Repeated-measures study. Setting: Motion capture laboratory. Participants: Thirty participants. Intervention: Each participant had dominant limb ankle kinematics recorded during 5 successful trials of a sudden inversion event and 30-cm drop landing task with each of 4 conditions (ARG, ASO ankle stabilizer [brace], closed-basket weave athletic tape [tape], and unbraced [control]). Main Outcome Measures: Peak ankle inversion angle, range of inversion motion (ROM), and time to peak inversion during the sudden inversion event, and ankle plantar- and dorsiflexion ROM during the drop landing were submitted to a 1-way repeated-measures analysis of variance to test the main effect of prophylaxis. Results: Participants exhibited greater inversion ROM with control compared with tape (P = .001), and greater plantar- and dorsiflexion ROM with ARG and control compared with brace (P = .02, P = .001) and tape (P = .02, P < .001). It took significantly longer to reach peak ankle inversion with brace and tape compared with ARG (P < .001, P = .001) and control (P = .01, P = .01). No significant difference in peak ankle inversion was observed between any condition (P > .05). Conclusion: The ARG may prevent ankle inversion angles where injury is thought to occur (reportedly >41°), but is less restrictive than existing prophylactics. The less restrictive ARG may make its use ideal during rehabilitation as it allows ankle plantar- and dorsiflexion motions, while preventing inversion related to injury.
Summer Davis, Xihe Zhu and Justin Haegele
Purpose: To examine differences in fitness test performance and the attributions made for the performances between high school students of different weight status. Methods: High school students (n = 185) completed the Progressive Aerobic Cardiovascular Endurance Run and the push-up fitness tests and then completed the modified Causal Dimension Scale to assess their attributions for their performances. Results: Students of a healthy weight performed higher than overweight/obese students on both fitness tests. There were no significant differences in attribution dimension scores for either test between healthy weight and overweight/obese students. Student performance played a significant role on the attribution dimension scores for both tests. Students primarily attributed their push-up and Progressive Aerobic Cardiovascular Endurance Run performance to ability. Conclusion: As student performance is significantly associated with attribution dimension scores, improving fitness test performance should subsequently foster adaptive attributions, creating a high expectancy for future success.
Jenna R. Starck, K. Andrew R. Richards, Michael A. Lawson and Oleg A. Sinelnikov
Purpose: Framed by occupational socialization theory, this study examined relationships among teachers’ perceived quality of assessment practices, workplace factors, and their conceptions of assessment. Methods: Ninety in-service physical education teachers from Alabama completed an online survey that attended to perceptions of organizational support, marginalization, valuation toward assessment, assessment quality, and class size. Associations were estimated using ordinary least squares regression. Results: In contrast to our initial hypothesis, no significant relationships were found between perceived assessment quality and perceived organizational support, marginalization, and class size. However, our regression analysis yielded significant results when assessment’s importance for education was the outcome variable. Discussion/Conclusions: The results indicated that teachers’ valuation of assessment included holding students and schools accountable, but was irrelevant to improving education. In addition, marginalization and perceived organizational support impacted teachers’ valuation toward using assessments to improve education. Research on assessment quality may depend first on widespread adoption of physical education teacher education assessment practices.
Catherine Mason and Matt Greig
Context: Lower back pain is prevalent in horse riders as a result of the absorption of repetitive and multiplanar propulsive forces from the horse. Global positioning system technology provides potential for in vivo measurement of planar loading during riding. Objective: To quantify the uniaxial loading at the lumbar and cervicothoracic spine during dressage elements. Design: Repeated measures, randomized order. Setting: Equestrian arena. Patients (or Other Participants): Twenty-one female dressage riders. Intervention(s): Each rider completed walk, rising trot, sitting trot, and canter trials in a randomized order. A global positioning system unit was placed within customized garments at C7 and L5, collecting triaxial accelerometry data at 100 Hz. Outcome Measures: PlayerLoad based on the rate of change of acceleration and calculated in the anteroposterior (AP), mediolateral, and vertical planes during each trial. Results: There was no significant main effect for global positioning system location in the AP (P = .76), mediolateral (P = .88), or vertical (P = .76) planes. There was a significant main effect for pace in all trials (P < .001), with successive elements eliciting significantly greater loading (P ≤ .03) in all planes in the order walk < rising trot < canter < sitting trot. There was a significant placement × element interaction only in the AP plane (P = .03) with AP loading greater at L5 during walk, rising trot, and canter trials, but greater at C7 during sitting trot. Conclusions: The significant main effect for dressage element was indicative of greater pace of the horse, with faster pace activities eliciting greater loading in all planes. In vivo measurement of spinal accelerometry has application in the objective measurement and subsequent management of lumbar load for riders.