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971.
Samuel T. Orange Phil Marshall Leigh A. Madden Rebecca V. Vince 《Journal of sports sciences》2019,37(11):1227-1234
This study examined the relationship between sit-to-stand (STS) power and physical function in adults with severe obesity. Thirty-eight adults (age: 44 ± 12 years; body mass index [BMI]: 45.2 ± 7.8 kg/m2) completed evaluations of STS power, strength and functional performance. STS power was measured with a wearable inertial sensor, strength was assessed with the isometric mid-thigh pull, and function was measured with the timed up-and-go (TUG), six-minute walk test (6MWT) and 30-s chair STS. Power and strength (normalised to body mass) entered regression models in addition to age, gender, BMI and physical activity (daily step count). Power displayed large univariate associations with TUG (r = 0.50) and 30-s chair STS (r = 0.67), and a moderate association with 6MWT (r = 0.49). Forward stepwise regression revealed that power independently contributed to TUG (β = ?0.40, p = 0.010), 30-s chair STS (β = 0.67, p < 0.001) and 6MWT performance (β = 0.27, p = 0.007). Power also appeared to be a superior determinant of function compared with strength. Power generated via the STS transfer largely underpins the ability to perform functional tasks in adults with severe obesity, although intervention studies are required to investigate a potentially causal relationship. 相似文献
972.
Kelly A. Mackintosh Nicola D. Ridgers Melitta A. McNarry 《Journal of sports sciences》2019,37(13):1506-1511
Physical activity (PA) is a key element in Cystic Fibrosis (CF) treatment strategies, yet little is known as to whether activity compensation occurs. This study examined whether PA and/or sedentary time on one day were temporally associated with time spent in these intensities the following day in youth with CF. Time spent sedentary and in different PA intensities were objectively-measured for seven consecutive days in 50 youth (22 boys; 12.0 ± 2.7 years); 25 with mild-to-moderate CF and 25 age- and sex-matched controls. Multilevel analyses (day and child) were conducted using generalised linear latent and mixed models. On any given day, every additional 10 minutes spent in sedentary time or moderate-to-vigorous physical activity (MVPA) were associated with 1.9 (95%CI: ?3.6 to ?1.2) and 12.4 (95%CI: ?22.1 to ?2.9) minutes less sedentary time the following day, respectively. These temporal associations were also observed when split by group (3.1 vs. 1.9 minutes for healthy and CF, respectively). These findings indicate that youth do not compensate their PA, irrespective of disease status, between days, but may compensate their sedentary time between days. Experimental studies are warranted to fully elucidate whether compensatory responses to PA and sedentary time occur, which is fundamental for informing PA promotion strategies. 相似文献
973.
Natalia Romero-Franco Juan C Fernández-Domínguez Juan A Montaño-Munuera Javier Romero-Franco Pedro Jiménez-Reyes 《Journal of sports sciences》2019,37(15):1787-1793
Muscle imbalance and deficit are key parameters for guiding rehabilitation and sports sessions and avoiding injuries. However, the high cost and non-portable nature of most instruments employed for muscle strength assessment frequently hamper an affordable evaluation in field conditions. This study evaluated the validity and reliability of a low-cost digital dynamometer to assess the maximal isometric strength of upper limb muscles. Fourteen physically active volunteers performed the main movements of the upper limb at maximal isometric strength: flexion-extension, internal-external rotation and abduction-adduction of the shoulder; and flexion-extension of both elbow and wrist. Validity was examined by comparing the strength values from the low-cost digital dynamometer and those measured by an isokinetic dynamometer, assumed as the gold standard. The correlation between both devices was perfect (r > 0.913), while Bland-Altman plots showed absolute agreement between both devices, the maximum range of the values of bias was ?0.99–1.00 N in wrist extension. Inter-tester and intra-tester reliability were excellent for all movements (ICC ≥ 0.855). The low-cost digital dynamometer showed strong validity and excellent reliability in assessing maximal isometric strength during the main movements of the upper limb. Professionals may use it for an affordable isometric muscle strength assessment in field situations. 相似文献
974.
Robert Dan Michael Cate A. Egan Lynda Nilges Ali Brian Robert Johnson 《Research quarterly for exercise and sport》2019,90(2):151-162
Purpose: A systematic review was conducted to identify facilitators and barriers to movement integration (MI) in elementary school classrooms. Method: Online databases (Educational Resources Information Center, Google Scholar, PsycINFO, and PubMed) served as data sources for the study. Following the PRISMA guidelines, relevant published research on MI was identified and screened for inclusion in a qualitative synthesis. Content analysis of the included articles (N = 28) was used to identify themes of MI facilitators and barriers. Facilitators and barriers were then categorized using a social-ecological framework. Results: A total of 12 themes of MI facilitators and barriers were identified and categorized into two social-ecological levels: institutional factors (e.g., administrative support, resources) and intrapersonal factors (e.g., teacher confidence, ease of implementation). Conclusion: This review can inform research and practice aimed at supporting the implementation of MI in elementary classrooms. 相似文献
975.
Liezel Hurter Alex V. Rowlands Stuart J. Fairclough Karl C. Gibbon Zoe R. Knowles Lorna A. Porcellato 《Journal of sports sciences》2019,37(16):1910-1918
This study aimed to validate the Sedentary Sphere posture classification method from wrist-worn accelerometers in children. Twenty-seven 9–10-year-old children wore ActiGraph GT9X (AG) and GENEActiv (GA) accelerometers on both wrists, and activPAL on the thigh while completing prescribed activities: five sedentary activities, standing with a phone, walking (criterion for all 7: observation) and 10-min free-living play (criterion: activPAL). In an independent sample, 21 children wore AG and GA accelerometers on the non-dominant wrist and activPAL for two days of free-living. Per cent accuracy, pairwise 95% equivalence tests (±10% equivalence zone) and intra-class correlation coefficients (ICC) analyses were completed. Accuracy was similar, for prescribed activities irrespective of brand (non-dominant wrist: 77–78%; dominant wrist: 79%). Posture estimates were equivalent between wrists within brand (±6%, ICC > 0.81, lower 95% CI ≥ 0.75), between brands worn on the same wrist (±5%, ICC ≥ 0.84, lower 95% CI ≥ 0.80) and between brands worn on opposing wrists (±6%, ICC ≥ 0.78, lower 95% CI ≥ 0.72). Agreement with activPAL during free-living was 77%, but sedentary time was underestimated by 7% (GA) and 10% (AG). The Sedentary Sphere can be used to classify posture from wrist-worn AG and GA accelerometers for group-level estimates in children, but future work is needed to improve the algorithm for better individual-level results. 相似文献
976.
Heather A. Starnes Meghan H. McDonough Jeffrey S. Wilson Daniel K. Mroczek Francine Laden Philip J. Troped 《Measurement in physical education and exercise science》2019,23(2):135-147
The purpose of this study was to examine the factorial invariance of the Abbreviated Neighborhood Environment Walkability Scale (NEWS-A) across subgroups based on demographic, health-related, behavioral, and environmental characteristics among Nurses’ Health Study participants (N = 2,919; age M = 73.0, SD = 6.9 years) living in California, Massachusetts, and Pennsylvania. A series of multigroup confirmatory factor analyses were conducted to evaluate increasingly restrictive hypotheses of factorial invariance. Factorial invariance was supported across age, walking limitations, and neighborhood walking. Only partial scalar invariance was supported across state residence and neighborhood population density. This evidence provides support for using the NEWS-A with older women of different ages, who have different degrees of walking limitations, and who engage in different amounts of neighborhood walking. Partial scalar invariance suggests that researchers should be cautious when using the NEWS-A to compare older adults living in different states and neighborhoods with different levels of population density. 相似文献
977.
The analysis of sport performance in competitive contexts has become synonymous with the use of a range of software applications and hardware e.g. heart rate monitors and gps systems. With the prevalence of technology in mind, a small but growing corpus of literature has begun to consider this phenomenon and its influence upon the coaching process. This study adds to this literature by detailing the autoethnographic experiences of a case study coach; Derek. A contextualised and richly described narrative account of Derek’s experience of using coaching applications is provided. Analysis of Derek’s narrative suggests that technology can be a useful means by which individuals make sense of their experience. Specifically, (1) technology can be a ‘ready-to-hand’ instrument that enhances the coaching process. Unfortunately, (2) technology may become the only and ‘calculative’ means by which individuals come to understand their performance. In such instances, it is important to note that (3) the videos we use to understand our performance are transformed and incomplete representations of lived athletic experiences. Thus, Derek’s story illustrates how technology can be both an enabler and barrier to athletes who wish to holistically understand their own lived experiences and engage in coach-athlete relationships. The accompanying analysis draws upon concepts from Heideggerian philosophy to add insight into the use of technology within the coaching process. In so doing, the study prompts coaches to critically view their coach-athlete relationships as situated in a wider world which contains, and can be mediated by, technology. In addition, Derek’s story (re)directs researchers and coaching practitioners interested in technology to a useful literature (philosophy of technology) which may further inform their understanding of coach-athlete relationships. 相似文献
978.
Road criterium and track bicycle racing occur at high speeds, demand repeated high power outputs, last 10–90?min, and offer little chance for recovery after the event. Consecutive evenings of criterium and track racing are respectively known as speed-week or six-day events and take place in evening hours over the course of a week. Given the schedule and timing of these competitions, return to homeostasis can be compromised. No recommendations exist on how to optimize recovery for cyclists participating in these types of repeated evening competitions. Criterium and track cyclists spend considerable time, near and above the individual lactate threshold and therefore mostly utilize carbohydrate as their chief energy substrate. Henceforth, pre – and post-race nutrition and hydration is examined and recommendations are brought forward for carbohydrate, protein, and fluid intake. As evening high-intensity exercise perturbs sleep, strategies to optimize sleep are discussed and recommendations for an optimal sleep environment are given. Active recovery is examined, and the benefits of a short duration low intensity exercise reviewed. Passive recovery methods such as compression garments and cold water immersion are recommended, while evidence for massage, pneumatic compression devices, and neuromuscular electrical stimulation is still lacking. Optimizing recovery strategies will facilitate a return to the resting state following strenuous night competition. 相似文献
979.
James H. Dugdale Calum A. Arthur Dajo Sanders Angus M. Hunter 《European Journal of Sport Science》2019,19(6):745-756
This study aimed to establish between-day reliability and validity of commonly used field-based fitness tests in youth soccer players of varied age and playing standards, and to discriminate between players without (“unidentified”) or with (“identified”) a direct route to professional football through their existing club pathway. Three-hundred-and-seventy-three Scottish youth soccer players (U11–U17) from three different playing standards (amateur, development, performance) completed a battery of commonly used generic field-based fitness tests (grip dynamometry, standing broad jump, countermovement vertical jump, 505 (505COD) and T-Drill (T-Test) change of direction and 10/20 m sprint tests) on two separate occasions within 7–14?days. The majority of field-based fitness tests selected within this study proved to be reliable measures of physical performance (ICC?=?0.83–0.97; p?.01). However, COD tests showed weaker reliability in younger participants (ICC?=?0.57–0.79; p?.01). The field-based fitness testing battery significantly discriminated between the unidentified and identified players; χ2 (7)?=?101.646, p?.001, with 70.2% of players being correctly classified. We have shown field-based fitness tests to be reliable measures of physical performance in youth soccer players. However, results from the 505COD and T-Test change of direction tests may be more variable in younger players, potentially due to complex demands of these tests and the limited training age established by these players. While the testing battery selected in this study was able to discriminate between unidentified and identified players, findings were inconsistent when attempting to differentiate between individual playing standards within the “identified” player group (development vs. performance). 相似文献
980.