ActivPAL™ determined sedentary behaviour,physical activity and academic achievement in college students

The aim of this study was to examine relationships between activPAL?-determined sedentary behavior (SB) and physical activity (PA) with academic achievement. A total of 120 undergraduates (N = 57 female; 20.6 ± 2.3 years) participated in the study. Academic achievement was measured as the grade point average obtained from all completed courses. Participants wore on the right tight an activPAL? for 7 days to determine total sedentary time, total number of sedentary breaks, sedentary bouts, standing time, light and moderate-to-vigorous physical activity (MVPA). Separate multiple linear regression models were performed to examine associations between SB variables and academic achievement. Light PA, MVPA, total sedentary time, total standing time, or total number of sedentary breaks were not related to academic achievement. Independently of PA, the amount of time spent in sedentary bouts of 10-20min during weekdays was positively related to academic achievement. Given that college students spend the majority of their workday in environments that encourage prolonged sitting, these data suggest that interruptions in prolonged periods of sitting time every 10-20min via short breaks may optimize cognitive operations associated with academic performance.     

Mediating Peer Teaching for Learning Games: An Action Research Intervention Across Three Consecutive Sport Education Seasons

Purpose: The purpose of this study was to provide an integrated analysis of a teacher’s peer-teaching mediation strategies, the student-coaches’ instruction, and the students’ gameplay development across 3 consecutive seasons of sport education. Method: Twenty-six 7th-grade students participated in 3 consecutive sport education seasons of invasion games (basketball, handball, and soccer). The research involved 3 action research cycles, 1 per season, and each cycle included the processes of planning, acting and monitoring, reflecting, and fact finding. Data collection consisted of videotape and audiotape records of all 47 lessons, a reflective field diary kept by the first author in the role of teacher-researcher, and a total of 24 semistructured focus-group interviews. Trustworthiness criteria for assuring the quality of qualitative research included extensive data triangulation, stakeholders’ crosschecking, and collaborative interpretational analysis. Results: Through the application of systematic preparation strategies, student-coaches were able to successfully conduct team instruction that resulted in students’ tactical development and improved performance. Aspects such as the study of predominant configurations of players’ gameplay and similar tactical principles across games within the same category prevented a setback in the complexity of the learning content addressed at the beginning of each season. Players also showed an increasing ability to adapt gameplay to game conditions. Conclusions: While sport education has the capacity to develop competent players, different levels of teacher guidance and learners’ instructional responsibility are necessary when teaching tactics.     

The validity and reliability of the GymAware linear position transducer for measuring counter-movement jump performance in female athletes

The current study aimed to assess the validity and test–retest reliability of a linear position transducer when compared to a force plate through a counter-movement jump in female participants. Twenty-seven female recreational athletes (19 ± 2 years) performed three counter-movement jumps simultaneously using the linear position transducer and force plate for validity. In addition, 11 elite female athletes (23 ± 6 years) performed 3 counter-movement jumps with the linear position transducer on three separate days for test–retest reliability. Pearson correlations for jump height between the devices were at a high level (r = .90), with the linear position transducer overestimating jump height by 7.0 ± 2.8 cm. The reliability measured by the linear position transducer resulted in a mean intraclass correlation of .70 for jump height, .90 for peak velocity, and .91 for mean velocity. The linear position transducer was reliable for measuring counter-movement jumps in elite female athletes; however, caution should be taken for one-off jump measures as it may over-estimate jump height.     

The effects of limb dominance and a short term,high intensity exercise protocol on both landings of the vertical drop jump: implications for the vertical drop jump as a screening tool

The effectiveness of vertical drop jumps (VDJs) to screen for non-contact ACL injuries is unclear. This may be contributed to by discrete point analysis, which does not evaluate patterns of movement. Also, limited research exists on the second landing of VDJs, potential lower limb performance asymmetries and the effect of fatigue. Statistical parametric mapping investigated the main effects of landing, limb dominance and a high intensity, intermittent exercise protocol (HIIP) on VDJ biomechanics. Twenty-two male athletes (21.9 ± 1.1 years, 180.5 ± 5.5 cm, 79.4 ± 7.8 kg) performed VDJs pre- and post-HIIP. Repeated measures ANOVA identified pattern differences during the eccentric phases of the first and second landings bilaterally. The first landing displayed greater (internal) knee flexor (η² = 0.165), external rotator (η² = 0.113) and valgus (η² = 0.126) moments and greater hip (η² = 0.062) and knee (η² = 0.080) flexion. The dominant limb generated greater knee flexor (η² = 0.062), external rotator (η² = 0.110) and valgus (η² = 0.065) moments. The HIIP only had one effect, increased thoracic flexion relative to the pelvis (η² = 0.088). Finally, the dominant limb demonstrated greater knee extensor moments during the second landing (η² = 0.100). ACL injury risk factors were present in both landings of VDJs with the dominant limb at potentially greater injury risk. Therefore, VDJ screenings should analyse both landings bilaterally.     

Can alcohol sponsorship be diluted by health messaging?

Concerns surround the association between alcohol advertising and alcohol consumption amongst audiences. Research has examined the link in broadcast sports, yet limited attention is directed towards newer media. This paper examines whether there is a link between alcohol sponsorship in sports games and alcohol brand recall, recognition and choice, and whether in-game health messages moderate this association. Simulated games designed specifically for this study are used to observe whether in-game alcohol sponsorship combined with embedded health messages affect the player’s brand awareness. Findings highlight the influence of in-game alcohol sponsorship placement on brand awareness, yet embedded health messages do not impact consumer behaviours. This research provides evidence suggesting regulations in games may be warranted and further examination of health messaging in sponsor brand placement necessary.     

Leadership in governance: Exploring collective board leadership in sport governance systems

The purpose of this paper is to introduce and explore a working conceptualisation of collective board leadership in a federal sport network. In this paper, the authors examine the relationship between collective leadership and governance systems specifically within the non-profit sport organisation context, bringing together notions of collective board leadership and collaborative governance. Neither concept has yet been presented in tandem for the benefit of developing sport governance knowledge and practice. As an outcome of the conceptualising, the authors make explicit the multiple levels of the sport governance system and pose two broad research directions that will help advance theory and drive a better understanding of collective board leadership within these types of governance systems. A central premise of this paper is that the sport management field is lacking literature that brings together leadership and governance, and that collective leadership is a topic where the intersection of leadership and governance renders advancement for both bodies of work. The authors offer implications for future work in collective leadership for sport governance.     

Effects of intensity on muscle-specific voluntary electromechanical delay and relaxation electromechanical delay

The purposes of this study were to examine: 1) the potential muscle-specific differences in voluntary electromechanical delay (EMD) and relaxation electromechanical delay (R-EMD), and 2) the effects of intensity on EMD and R-EMD during step incremental isometric muscle actions from 10 to 100% maximal voluntary isometric contraction (MVIC). EMD and R-EMD measures were calculated from the simultaneous assessments of electromyography, mechanomyography, and force production from the vastus lateralis (VL), vastus medialis (VM), and rectus femoris (RF) during step isometric muscle actions. There were no differences between the VL, VM, and RF for the voluntary EMD_E-M (onsets of the electromyographic to mechanomyographic signals), EMD_M-F (onsets the mechanomyographic to force production), or EMD_E-F (onsets of the electromyographic signal to force production) as well as R-EMD_E-M (cessation of electromyographic to mechanomyographic signal), R-EMD_M-F (cessation of mechanomyographic signal to force cessation), or R-EMD_E-F (cessation of electromyorgraphic signal to force cessation) at any intensity. There were decreases in all EMD and R-EMD measures with increases in intensity. The relative contributions from EMD_E-M and EMD_M-F to EMD_E-F as well as R-EMD_E-M and R-EMD_M-F to R-EMD_E-F remained similar across all intensities. The superficial muscles of the quadriceps femoris shared similar EMD and R-EMD measurements.     

Analysis of publications of the pilot issue of the data collection of the All-Russia Institute of Scientific and Technical Information of the Russian Academy of Sciences “Industry of Nanosystems and Nanomaterials”

The pilot issue of the data collection of the All-Russian Institute of Scientific and Technical Information of the Russian Academy of Sciences “Industry of Nanosystems and Nanomaterials” gives an approximate view of the state of this field of science at the beginning of 2007. The topics of articles in the pilot issue are analyzed. The directions of development of nanotechnologies are shown. The basic types of nanomaterials, the methods of their production, and their properties and applications are given.     

Efficient algorithms for ranking with SVMs

RankSVM (Herbrich et al. in Advances in large margin classifiers. MIT Press, Cambridge, MA, 2000; Joachims in Proceedings of the ACM conference on knowledge discovery and data mining (KDD), 2002) is a pairwise method for designing ranking models. SVMLight is the only publicly available software for RankSVM. It is slow and, due to incomplete training with it, previous evaluations show RankSVM to have inferior ranking performance. We propose new methods based on primal Newton method to speed up RankSVM training and show that they are 5 orders of magnitude faster than SVMLight. Evaluation on the Letor benchmark datasets after complete training using such methods shows that the performance of RankSVM is excellent.