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Leila Hedayatrad, Tom Stewart and Scott Duncan

Introduction: Accelerometers are commonly used to assess time-use behaviors related to physical activity, sedentary behavior, and sleep; however, as new accelerometer technologies emerge, it is important to ensure consistency with previous devices. This study aimed to evaluate the concurrent validity of the commonly used accelerometer, ActiGraph GT3X+, and the relatively new Axivity AX3 (fastened to the lower back) for detecting physical activity intensity and body postures when using direct observation as the criterion measure. Methods: A total of 41 children (aged 6–16 years) and 33 adults (aged 28–59 years) wore both monitors concurrently while performing 10 prescribed activities under laboratory conditions. The GT3X+ data were categorized into different physical activity intensity and posture categories using intensity-based cut points and ActiGraph proprietary inclinometer algorithms, respectively. The AX3 data were first converted to ActiGraph counts before being categorized into different physical activity intensity categories, while activity recognition models were used to detect the target postures. Sensitivity, specificity, and the balanced accuracy for intensity and posture category classification were calculated for each accelerometer. Differences in balanced accuracy between the devices and between children and adults were also calculated. Results: Both accelerometers obtained 74–96% balanced accuracy, with the AX3 performing slightly better (∼4% higher, p < .01) for detecting postures and physical activity intensity. Error in both devices was greatest when contrasting sitting/standing, sedentary/light intensity, and moderate/light intensity. Conclusion: In comparison with the GT3X+ accelerometer, AX3 was able to detect various postures and activity intensities with slightly higher balanced accuracy in children and adults.

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Marte Bentzen, Danielle Alexander, Gordon A. Bloom and Göran Kenttä

The purpose of this scoping review was to provide a broad overview of the literature pertaining to parasport coaches, including information regarding the size and scope of research, the populations and perspectives obtained, and the type of methods used to conduct the research. Data were collected and analyzed using a six-stage framework for conducting scoping reviews. The results revealed that the majority of articles were based on interviews, and an overwhelming majority of the participants were men coaching at the high-performance level in North America. Three of the most frequent topics were becoming a parasport coach, being a parasport coach, and having general parasport coaching knowledge. Articles ranged in date from 1991 to 2018, with 70% of empirical articles published from 2014 onward, indicating an emerging interest in this field of research. This review has the potential to advance the science and practice of parasport coaching at all levels.

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Gennaro Boccia, Marco Cardinale and Paolo Riccardo Brustio

Purpose: To quantify how many of the top 50 under-18 (U18) sprinters in the world managed to become top 50 ranked as adult competitors. The authors also described the career trajectory of athletes ranked in the top 50 during either U18 or senior category. Methods: A total of 4924 male and female athletes competing in sprint races and ranked in the International Association of Athletics Federations (now World Athletics) lists in any of the seasons between the 2000 and 2018 were included in the study. The athletes ranked in the top 50 positions of all-time lists during U18, senior, or both categories were analyzed. Results: Only 17% of the male and 21% of the female top 50 ranked U18 managed to become top 50 ranked senior athletes. The top 50 ranked senior athletes consistently produced yearly larger improvements during late adolescence and early adulthood compared with those who ranked in the top 50 at U18. Furthermore, top 50 ranked senior athletes reached their peak performance later compared with the top 50 ranked only in U18. Conclusions: This study confirms that early success in track and field is not a good predictor of success at senior level in sprinting events. The yearly performance improvements and their tracking provide the most suitable approach to identify athletes more likely to succeed as elite performers in adulthood. The authors hope that the results of this study can provide useful comparative data and reference criteria for talent-identification and -development programs.

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John F.T. Fernandes, Kevin L. Lamb, Jonathan P. Norris, Jason Moran, Benjamin Drury, Nattai R. Borges and Craig Twist

Aging is anecdotally associated with a prolonged recovery from resistance training, though current literature remains equivocal. This brief review considers the effects of resistance training on indirect markers of muscle damage and recovery (i.e., muscle soreness, blood markers, and muscle strength) in older males. With no date restrictions, four databases were searched for articles relating to aging, muscle damage, and recovery. Data from 11 studies were extracted for review. Of these, four reported worse symptoms in older compared with younger populations, while two have observed the opposite, and the remaining studies (n = 6) proposed no differences between age groups. It appears that resistance training can be practiced in older populations without concern for impaired recovery. To improve current knowledge, researchers are urged to utilize more ecologically valid muscle-damaging bouts and investigate the mechanisms which underpin the recovery of muscle soreness and strength after exercise in older populations.

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Mingda Li, Weidong Li, Junyoung Kim, Ping Xiang, Fei Xin and Yan Tang

Self-efficacy theory assumes that students’ efficacy beliefs affect their performance through process variables, including behavior, cognition, and affection. The purpose of this study was to utilize self-efficacy theory as a theoretical framework to propose a conceptual model of a mediating relationship among perceived motor skill competence, successful practice trials, and motor skill performance in physical education. In addition, the authors reviewed the literature to provide evidence to support the potential mediating relationship by following the steps recommended by Baron and Kenny. This paper is significant because the authors integrated the literature of motor development/learning and physical education pedagogy to propose a conceptual model where successful practice trials would act as a behavioral mediator through which perceived motor skill competence affects students’ motor skill performance. This conceptual model can guide future research to identify students’ behaviors affecting their skill development, thus helping teachers develop pedagogies to improve motor skill performance in physical education.

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Anna M.J. Iveson, Malcolm H. Granat, Brian M. Ellis and Philippa M. Dall

Objective: Global positioning system (GPS) data can add context to physical activity data and have previously been integrated with epoch-based physical activity data. The current study aimed to develop a framework for integrating GPS data and event-based physical activity data (suitable for assessing patterns of behavior). Methods: A convenience data set of concurrent GPS (AMOD) and physical activity (activPAL) data were collected from 69 adults. The GPS data were (semi)regularly sampled every 5 s. The physical activity data output was presented as walking events, which are continuous periods of walking with a time-stamped start time and duration (to nearest 0.1 s). The GPS outcome measures and the potential correspondence of their timing with walking events were identified and a framework was developed describing data integration for each combination of GPS outcome and walking event correspondence. Results: The GPS outcome measures were categorized as those deriving from a single GPS point (e.g., location) or from the difference between successive GPS points (e.g., distance), and could be categorical, scale, or rate outcomes. Walking events were categorized as having zero (13% of walking events, 3% of walking duration), or one or more (52% of walking events, 75% of walking duration) GPS points occurring during the event. Additionally, some walking events did not have GPS points suitably close to allow calculation of outcome measures (31% of walking events, 22% of walking duration). The framework required different integration approaches for each GPS outcome type, and walking events containing zero or more than one GPS points.

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Alex Brun and Michelle A. Sandrey

Context: Joint mobilizations have been studied extensively in the literature for the glenohumeral joint and talocrural joint (ankle). Consequently, joint mobilizations have been established as an effective means of improving range of motion (ROM) within these joints. However, there is a lack of extant research to suggest these effects may apply within another critical joint in the body, the hip. Objective: To examine the immediate effects of hip joint mobilizations on hip ROM and functional outcomes. Secondarily, this study sought to examine the efficacy of a novel hip mobilization protocol. Design: A prospective exploratory study. Setting: Two research labs. Patients or Other Participants: The study included 19 active male (n = 8) and female (n = 11) college students (20.56 [1.5] y, 171.70 [8.6] cm, 72.23 [12.9] kg). Interventions: Bilateral hip mobilizations were administered with the use of a mobilization belt. Each participant received hip joint mobilization treatments once during 3 weekly sessions followed immediately by preintervention and postintervention testing/measurements. Testing for each participant occurred once per week, at the same time of day, for 3 consecutive weeks. Hip ROM was the first week, followed by modified Star Excursion Balance Test the second week and agility T test during the third week. Main Outcomes Measures: Pretest and posttest measurements included hip ROM for hip flexion, extension, abduction, adduction, internal and external rotation, as well as scores on the modified Star Excursion Balance Test (anterior, posterolateral, and posteromedial directions) and agility T test. Results: A significant effect for time was found for hip adduction, internal and external rotation ROM, as well as the posterolateral and posteromedial directions of the modified Star Excursion Balance Test. A separate main effect for both limbs was found for adduction and internal rotation ROM. Conclusion: Isolated immediate changes in ROM and functional outcomes were evident. Further evaluation is needed.

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Saša Krstulović, Andrea De Giorgio, Óscar DelCastillo Andrés, Emerson Franchini and Goran Kuvačić

The main aim of this investigation was to determine the effect of high contextual interference (HCI) and low contextual interference (LCI) on motor learning of falling techniques. Thirty-five kinesiology students (21 males and 14 females; mean ± SD, age = 19.4 ± 0.69 years) were randomly assigned to the HCI or LCI practice group. The participants’ task was to learn two judo falling techniques on both sides over 3 weeks. The two-way analysis of variance found no difference between LCI and HCI in the performance at the pretest, posttest, retention, and transfer. Both groups improved posttest and retention performance. Finally, differences were found for both groups between the falling performance in the posttest and the application test (except for the right yoko ukemi fall in the HCI). Lower application test scores led to the conclusion that the 3-week treatment was insufficient to reach the application level of the falling techniques.

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Emma Pullen, Daniel Jackson, Michael Silk, P. David Howe and Carla Filomena Silva

In the United Kingdom, significant changes have occurred in the Paralympic media production environment and style of Paralympic broadcasting. Given the generative nature of media texts on cultural representation, the authors explore the circulation of disability narratives in contemporary Paralympic media coverage. Drawing on an integrated data set that brings together textual analysis and audience perceptions, the authors highlight the presence of three disability narratives, termed: extraordinary normalcy, ableist rehabilitation, and sporting ablenationalism. The authors unpack the ways these three narratives differ from the widely and commonly used “supercrip” critique and discuss the implications of these narratives, and the wider cultural discourses and dialogue they generate, in terms of inclusion/exclusion and progressive social change.