Differences in Impact and Load During Collegiate Rugby 7s

Rugby 7s is a sport played with seven players, and two, 7-minute halves, played on a standard rugby field of 100 meters long by 70 meters wide. Impacts with forces greater than 10.0 Gs are an often occurrence in rugby 7s, and the occurrence can be quite frequent in such a short period of time (14 minutes of match play). Multiple matches are played in a day or throughout a weekend in tournament format thus adding to the load on players and current research on the amount of impact and load players experience is lacking in a U.S. collegiate population. Purpose: The purpose of this investigation was to assess differences in impact and load during collegiate rugby 7s matches. Methods: Data was collected at Indiana University from male collegiate rugby 7s players (n = 15) by their head coach using GameTraka (Sports Performance Tracking, Victoria, Australia) during their 2019 season. Participants wore GPS units that collected data on impact and load by position groups forwards (FW), backs (BK), and scrum halves (SH). A one-way ANOVA was used to determine between group differences by each half of play with Tukey post-hoc analyses to reveal differences between positions. A two-way repeated measures ANOVA was used to determine if differences existed across matches by player position. A p-value of \u3c0.05 was set to determine the level of statistical significance. Results: Data analyses revealed a significant difference in number of impacts during the first half of match 1 (p = 0.014). Post-hoc analyses indicated FW incurred a significantly higher number of impacts than BK (p = 0.046), as well as more impacts than SH (p = 0.012). During the second half of play, the only match with a significant difference was match 5. Both summation of horizontal forces (loading 2D) as well as summation of horizontal and vertical forces (loading 3D) to the athlete revealed significant main effects. For the loading 2D and loading 3D during match 5, post-hoc analyses revealed significant differences between BK and SH at p = 0.048 and p = 0.045, respectively. In comparison of position across matches, no significant differences were found for impacts, 2D, or 3D loading. No significant differences were found across the five matches. Conclusion: This data suggests that the number of impacts is higher in the first half, with FW having significantly more impacts when compared to BK and SH. This is likely explained by task differences between FW, BK, and SH as FW are required to compete in scrums and more rucks than either BK or SH and tend to encounter contact more frequently. Differences in the second half occurred only in match 5 with SH being subjected to more forces than BK. This effect is likely a result of the positional differences as SH follow the course of play much more so than BK. This data supports that FW incur the greatest amount of collisions in rugby 7s compared to other positions also being a byproduct of the role that FW play in rugby 7s. There was no significant difference in loading and impact across matches

Offseason Body Composition Changes Detected by Dual-Energy X-Ray Absorptiometry Versus Multifrequency Bioelectrical Impedance Analysis in Collegiate American Football Athletes

In American football, offseason training is designed to promote increases in muscle strength and size in athletes. Tracking changes in body composition may confer key information about the effectiveness of training programs to football practitioners. PURPOSE: The present study assessed the relationship between body composition changes estimated by dual-energy x-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA) in football players during the initial period of an offseason training program. METHODS: Body composition in 29 NCAA Division III American football players (mean ± SD; age: 19.7 ± 1.5 y; height: 179.8 ± 6.6 cm; body mass [BM]: 96.1 ± 12.6 kg; DXA body fat: 20.9 ± 4.4%) was estimated using BIA (InBody 770) and DXA (Hologic Horizon) before and after a seven-week training intervention. Repeated measures analysis of variance, concordance correlation coefficients, and Bland-Altman analysis alongside linear regression were used to detect differences in cross-sectional estimates and change values, the strength of correlation, and determine the degree of proportional bias between methods, respectively. RESULTS: Significant method by time interactions were observed for BM (p = 0.03), arms fat-free mass (FFM) (p = 0.03), and legs FFM (p = 0.01). Post hoc comparisons indicated that DXA – but not BIA – detected increases in FFM of the arms and legs. Time main effects indicated an increase in total FFM (p = 0.004) and trunk FFM (p = 0.002) from pre to post. Finally, method main effects indicated higher leg FM values for DXA (p \u3c 0.001) and higher trunk FM values for BIA (p \u3c 0.001). No significant effects were observed for total FM (p = 0.92) or arms FM (p = 0.13). Changes in total BM (CCC = 0.96), FFM (CCC = 0.49), and fat mass (CCC = 0.50) were significantly correlated between BIA and DXA. CONCLUSION: DXA and BIA may similarly track increases in whole-body FFM in American collegiate football players; however, BIA may possess less sensitivity to detect segmental FFM increases, particularly in the appendages

Performance and Body Composition Changes Following an Offseason Training Period in DIII Collegiate American Football Athletes

Current literature shows that body composition and increased muscle mass correlate with improved performance for American football players thus assessment of these variables at appropriate times throughout competitive cycle are important for tracking individual adaptions but also in assessing the effectiveness of the prescribed training program. PURPOSE: This study assessed changes in anaerobic performance, total body mass (BM), fat-free mass (FFM), and percent body fat (PBF) in football players following a seven-week offseason mesocycle. METHODS: 29 NCAA Division III football players (mean ± SD; age: 19.7 ± 1.5 y; height: 179.8 ± 6.6 cm; body mass [BM]: 96.1 ± 12.6 kg; DXA body fat: 20.9 ± 4.4%) participated in assessments of performance and body composition body pre- and post- mesocycle. Performance testing was assessed at pre- and post-training timepoints on a subset of athletes that were not restricted (injury, etc.) from maximal testing at these timepoints. This data was from the initial cycle of their offseason training program which included seven weeks of hypertrophy focused training volumes. Performance tests administered included: bench press 1 RM (BP), bench press reps (BPR), incline bench press, back squat 1RM (BS), front squat 1 RM (FS), hang clean 3 RM, 40-yard dash (YD), broad jump, vertical jump (VJ), and pro agility shuttle. BM, FFM, and PBF were estimated via dual x-ray absorptiometry (DXA). RESULTS: Performance improved in all tests except for broad jump and pro agility shuttle. Post-mesocycle performance increases were observed in BP (p \u3c 0.001), BPR (p \u3c0.001), BS (p \u3c0.001), FS (p \u3c 0.001), YD (p \u3c 0.001), and VJ (p \u3c 0.001). Significant training induced changes were observed for: BM increased 1.12kg (p \u3c 0.01962), PBF decreased by 0.686 kg (p \u3c0.004), and FFM increased by 1.57 kg (p \u3c 0.0001). CONCLUSION: This study confirms that a well-structured strength and conditioning program for Division III football players will improve performance in a variety of strength and power related assessments. These changes, though observed over a relatively short amount of time, can translate to competitive performance in conjunction with improved body composition and fat-free mass increases

Lower Limb Muscle Activation and Recruitment Patterns Measured via Electromyography in Back Squat Variations

The squat is a fundamental exercise performed by athletes to improve muscular fitness. There are many variations of the back squat including the chained squat, box squat, and barefoot squat. Strength training literature recommends the inclusion of proper squats for athletes as well as variations of the squat to improve adaptations. Several studies have been published that analyze the neuromuscular relationship using electromyography (EMG) but few studies exist that compare EMG responses between squat variation. Purpose: Thus, the purpose of this investigation was to compare the electromyography (EMG) amplitude of the gluteus maximus (GM), biceps femoris (BF), and vastus lateralis (VL) during a back, chained, barefoot, and box squat. Methods: Seven college-aged resistance trained volunteers, three men and four women (age 21.4 ± 0.98; height 166.87 ± 12.84cm; weight 77.44 ± 18.52kg; percent body fat 22.97 ± 9.51 BF%) were recruited for this study and completed a baseline testing session to determine 70% of their 1 repetition maximum (1RM) and familiarize subjects with the squat variations: box, barefoot, back, and chained squats. Following the first testing session, each subsequent session occurred after a one-week washout period. EMG testing sites were located at each session via anatomical landmarks and palpation then abraded prior to applying surface electrodes in a bipolar configuration. Using the BIOPAC MP3X and Biopac system software, EMG activity was recorded through an integrated, high pass frequency filter. Participants performed 5 sets of 10 repetitions for each randomly assigned squat variation and data was analyzed for peak and mean values from the 1st set. Frequencies were normalized and recorded in millivolts (mV). The values from the subjects’ dominant leg were then analyzed using a one-way ANOVA with a p-value of \u3c0.05 was set to determine the level of statistical significance. Results: No significant differences were observed between back squat variations for both peak (VL: p = 0.817; BF: p = 0.941; GM: p = 0.766) and mean (VL: p = 0.877; BF: p = 0.738; GM: p = 0.602) EMG values. VL mean activation values (mean±SD) were as followed for the squat variations: back 0.254 ± 0.164, barefoot 0.297 ± 0.179, box 0.337 ± 0.239, chained 0.294 ± 0.155. VL peak activation values (mean±SD) were as followed for the squat variations: back 0.522 ± 0.335, barefoot 0.652 ± 0.395, box 0.720 ± 0.486, chained 0.650 ± 0.320. Conclusions: Despite varying levels of VL peak activation, this data suggests EMG activity for each muscle group does not seem to vary significantly between the squat variations used in this study. Data was collected from each leg which could be used in a future study to identify imbalances when compared to leg dominance across squat variation. The results could be applied clinically and practically in that multiple back squat variations can elicit similar muscular activation levels in a resistance-trained population

Reflections on using a community-based and multisystem approach to transforming school-based intervention for children with developmental motor disorders

Evidence-based management of Developmental Coordination Disorder (DCD) in school-age children requires putting into practice the best and most current research findings, including evidence that early identification, self-management, prevention of secondary disability, and enhanced participation are the most appropriate foci of school-based occupational therapy. Partnering for Change (P4C) is a new school-based intervention based upon these principles that has been developed and evaluated in Ontario, Canada over an 8-year period. Our experience to date indicates that its implementation in schools is highly complex with involvement of multiple stakeholders across health and education sectors. In this paper, we describe and reflect upon our team’s experience in using community-based participatory action research, knowledge translation, and implementation science to transform evidence-informed practice with children who have DCD

On the chemical bonding effects in the Raman response: Benzenethiol adsorbed on silver clusters

We study the effects of chemical bonding on Raman scattering from benzenethiol chemisorbed on silver clusters using time-dependent density functional theory (TDDFT). Raman scattering cross sections are computed using a formalism that employs analytical derivatives of frequency-dependent electronic polarizabilities, which treats both off-resonant and resonant enhancement within the same scheme. In the off-resonant regime, Raman scattering into molecular vibrational modes is enhanced by one order of magnitude and shows pronounced dependence on the orientation and the local symmetry of the molecule. Additional strong enhancement of the order of $10^2$ arises from resonant transitions to mixed metal--molecular electronic states. The Raman enhancement is analyzed using Raman excitation profiles (REPs) for the range of excitation energies $1.6-3.0$ eV, in which isolated benzenethiol does not have electronic transitions. The computed vibrational frequency shifts and relative Raman scattering cross sections of the metal--molecular complexes are in good agreement with experimental data on surface enhanced Raman scattering (SERS) for benzenethiol adsorbed on silver surfaces. Characterization and understanding of these effects, associated with chemical enhancement mechanism, may be used to improve the detection sensitivity in molecular Raman scattering.Comment: 25 pages, 14 figures. Phys. Chem. Chem. Phys. in pres

The Italian London of John North: Cultural contact and linguistic encounter in early modern England

This article takes as its subject the remarkable diary kept by a young English gentleman named John North from 1575 to 1579. On his journey home from Italy in 1575 -77, North changed the language of his diary from English to Italian. On his return to London, he continued to keep a record of his everyday life in Italian. This article uses North's diary as a starting point from which to reconstruct the social and sensory worlds of a returned traveler and Italianate gentleman. In doing so, it offers a way of bridging the gap between individual experiences and personal networks on the one hand, and the wider processes of cultural encounter and linguistic contact on the other

Gothic Revival Architecture Before Horace Walpole's Strawberry Hill

The Gothic Revival is generally considered to have begun in eighteenth-century Britain with the construction of Horace Walpole’s villa, Strawberry Hill, Twickenham, in the late 1740s. As this chapter demonstrates, however, Strawberry Hill is in no way the first building, domestic or otherwise, to have recreated, even superficially, some aspect of the form and ornamental style of medieval architecture. Earlier architects who, albeit often combining it with Classicism, worked in the Gothic style include Sir Christopher Wren, Nicholas Hawksmoor, William Kent and Batty Langley, aspects of whose works are explored here. While not an exhaustive survey of pre-1750 Gothic Revival design, the examples considered in this chapter reveal how seventeenth- and eighteenth-century Gothic emerged and evolved over the course of different architects’ careers, and how, by the time that Walpole came to create his own Gothic ‘castle’, there was already in existence in Britain a sustained Gothic Revivalist tradition

Factors related to the continuing education needs of a selected group of professional engineers in British Columbia

The rapidly increasing rate of advancement in the store of technical and scientific knowledge has greatly affected the working engineer, not only in British Columbia, but throughout the world. This acceleration of new technological knowledge has resulted in a serious problem within the engineering profession - that is the erosion (obsolescence) of technical knowledge within the profession due to the diminishing value of once proven methods, and an emergence of new concepts and developments. The engineer is finding that the education he received in the university may not be sufficient to meet his changing needs throughout his working life-time. Moreover, the qualifications of the engineer in today's swiftly advancing technical world are very perishable commodities. Therefore, constant exposure to new advances in science and technology is vital in order to maintain his intellectual skills and his job competence; and thus enhance the state-of-the-art in his profession. The purpose of this study was to construct a profile of the professional engineer in British Columbia, and to determine factors that were related to the nature and extent of his participation in continuing education; his feeling about the need for regular continuing education programs; and whether or not these needs are presently being met. The selected random sample represented 136 of the nearly 5,000 engineers with full registration in the Association of Professional Engineers in the Province of British Columbia. The data was collected by means of a personal interview schedule developed especially for a face-to-face exchange of information with the respondents. The research design established 327 factors to be used for development of the engineer's profile, and 178 factors to be used for cross-tabulation analysis for significant relationships with the 3 selected dependent variables. Of the 178 independent variables, 98 were related to the engineer's occupational environment, 20 were personal characteristics, 43 related to educational experiences, and 17 were geographic factors. The 3 dependent variables were: the engineer's level of participation in continuing education; his feeling about the need for regular continuing education programs; and whether or not these needs are presently being met. The chi square statistic coupled with linear and multiple regression analysis were used to determine statistically significant relationships between the variables. The "typical engineer" was found to be one who: was over 45 years of age, was registered in 1 of 3 major fields (civil, mechanical, or electrical), worked for a company for over 10 years, graduated over 10 years ago, had 3 or more employers, was involved in some supervision of others, was married and lived in the lower mainland. The "typical participant" in course work or training programs was a younger man, on a lower salary, with strong encouragement from his company and his spouse to continue his education. There was no statistically significant relationship between the 3 dependent variables, indicating no direct connection between the engineer's level of participation and his feelings about continuing education. However, independent factors related to all 3 dependent variables include the company policy toward continuing education, his level of satisfaction with his work, type of job function he performs, his age, income, number of years he has worked as an engineer, his home environment - especially the attitude of his spouse toward his participation, year and field of professional registration, sources of further education he would choose in the future, his attitude toward "technical obsolescence" of knowledge in the engineering profession, the distance to the professional society meetings, and the availability of courses in his local area. The engineer's level of participation in continuing education was significantly related to 9 occupational factors, 3 personal factors, 8 educational factors and 2 geographic factors. The engineer's feeling about the need for regular continuing education programs for his specific job function was significantly related to 27 occupational factors, 5 personal factors, 11 educational factors and 1 geographic factor. The engineer's feeling toward his continuing education needs presently being met was significantly related to 20 occupational factors, 4 personal factors, 8 educational factors and 2 geographic factors. The results of the study indicate a need for further research on the continuing education needs of specific groups of engineers such as engineers in isolated areas, older engineers, and engineers in interdisciplinary roles, Further study is also needed on the implications of self-directed learning, and the "technical obsolescence" of engineering knowledge in British Columbia. It was recommended that better use be made of the vast wealth of technical experience found in the B.C. engineering profession. Moreover, a concerted joint effort should be made on the part of the professional association, the educational institutions, industry, and the government to better serve the continuing education needs of the engineers in British Columbia.Education, Faculty ofEducational Studies (EDST), Department ofGraduat