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The aim of the present study was to determine the reliability and differences between three fascicle length (FL) estimation methods when utilizing a 10-cm ultrasound (US) probe. Thirteen males (24.1 ± 3.8 years, 79.3 ± 14 kg, 179 ± 6.6 cm) participated. Bicep femoris long head (BFLH) US images were collected on two separate occasions. Three previously established extrapolation methods were utilized. Near-perfect reliability was observed for all methods. Criterion estimation resulted in a significant, trivial (p = 0.016,g = 0.17) increase in FL compared to the basic trigonometry equation with non-significant, trivial increase (p = 0.081,g = 0.10) between the criterion and partial measure method. The partial measure method was not significantly or meaningfully greater than the basic trigonometry method (p = 0.286,g = 0.08). Both alternative methods demonstrated unacceptable LOA (>5%), with heteroscedasticity. All methods of extrapolation are reliable and could be used over time. However, as methods are not comparable, there could be a rationale to utilize underestimated results to ensure a degree of cushioning.

Objective: This study aimed to compare the maximum and rapid force production of Spanish football players and explore the differences between age group and level of competition. Methods: A cross-sectional study was developed to evaluate the peak force (PF), relative PF, and rate of force development over 250 ms (RFD0−250) during the isometric midthigh pull between groups of football players based on age group (senior vs junior) and level of competition (national vs regional). Using a portable isometric rig, 111 football players performed 2 isometric midthigh-pull trials on a force plate. Two-way analysis of variance with Bonferroni post hoc correction was applied, and statistical significance was set at P ≤.05. The PF, relative PF, and RFD0−250 0, 25, 50, 75, and 100 percentiles were also calculated and descriptively reported, separated by age group and level of competition. Results: The analysis of variance revealed a significant main effect of the level of competition for the PF (P <.001), relative PF (P =.003), and RFD0−250 (P <.001). There was a significant main effect of age group for the PF (P <.001). There was a significant interaction effect of the age group × level of competition for relative PF (P =.014). National players were stronger than regional players on the PF and RFD0−250 (P <.001). Senior players were stronger than junior players for the PF (P <.001). Conclusions: Maximum and rapid force production are crucial for Spanish football players as they progress in both level of competition and age group. Practitioners should encourage young football players to prioritize strength development to improve their athletic performance. [ABSTRACT FROM AUTHOR]

Given the increasing prevalence of podcast listening, especially among young adults with college education, it is important to consider how student-produced podcasts can impact the student experience in the classroom, contribute to a more participatory course, and help achieve learning objectives. To engage these issues, this article reflects on the podcast assignment completed by five courses of students, three introductory American Politics classes and two Political Ideologies classes. This article seeks to examine how podcasts can work as a tool for students to research, analyze, synthesize, and present political information in a specific pedagogical and rhetorical setting; in the course of doing so, students become actively engaged with the audio public political sphere. I focus on assignment design, learning objectives, and my own pedagogical reflections in order to reach some tentative ideas about the pedagogical potential of podcasts in the political science classroom.

Introduction: One way to understand a profession is to examine the job tasks undertaken by professionals within the field. The profession of vision rehabilitation therapy is examined by finding the frequency at which 100 specific job tasks are performed on average by current vision rehabilitation therapists (VRTs). Fifty-one of the job task frequencies are compared to 1989 frequencies for changes across the last 28 years. Methods: An anonymous online survey was carried out with current and recently retired VRTs. Participants were asked to rate the frequency at which they perform 100 specific job tasks and 13 demographic questions. Results: One hundred eighty-nine practitioners completed the survey. Mean frequencies for the 100 job tasks fell between a low of 1.08 (slightly above "do not perform the task") for "writes grants for funding of agency services" and a high of 5.51 (above "perform 4 or 5 times a week") for "writes case notes and reports for documentation." Half of the 51 comparable job tasks indicated statistically significant changes in frequency across the 28-year period. Discussion: Statistically significant changes in job task frequencies occurred across job roles of teaching, case management, and professional or administrative activities, indicating that many aspects of the therapist's job have changed. Individualized teaching remains a common aspect of the job, personalizing the skills taught and the teaching methods, for the individual client. VRTs are less frequently providing consultation to medical and community organizations. Implications for practitioners: The results presented provide an understanding of current job tasks of a practicing VRT. Understanding the changing trends of job tasks may inform university personnel preparation programs to better prepare students for employment demands. Decreasing community outreach may negatively affect the visibility of blind rehabilitation services and inadvertently affect referrals for vision rehabilitation therapy services.

This study aimed to compare the kinetics between the push press (PP), push jerk (PJ), and split jerk (SJ). Sixteen resistance-trained participants (12 men and 4 women; age: 23.8 ± 4.4 years; height: 1.7 ± 0.1 m; body mass: 75.7 ± 13.0 kg; weightlifting experience: 2.2 ± 1.3 years; one repetition maximum [1RM] PP: 76.5 ± 19.5 kg) performed 3 repetitions each of the PP, PJ, and SJ at a relative load of 80% 1RM PP on a force platform. The kinetics (peak and mean force, peak and mean power, and impulse) of the PP, PJ, and SJ were determined during the dip and thrust phases. Dip and thrust displacement and duration were also calculated for the three lifts. In addition, the inter-repetition reliability of each variable across the three exercises was analysed. Moderate to excellent reliability was evident for the PP (Intraclass correlation coefficient [ICC] = 0.91–1.00), PJ (ICC = 0.86–1.00), and SJ (ICC = 0.55–0.99) kinetics. A one-way analysis of variance revealed no significant or meaningful differences (p > 0.05, η2 ≤ 0.010) for any kinetic measure between the PP, PJ, and SJ. In conclusion, there were no differences in kinetics between the PP, PJ, and SJ when performed at the same standardised load of 80% 1RM PP. [ABSTRACT FROM AUTHOR]

The Nordic hamstring exercise (NHE) is effective at decreasing hamstring strain injury risk. Limited information is available on the in vivo mechanics of the bicep femoris long head (BFLH) during the NHE. Therefore, the purpose of this study was to observe kinematic, neuromuscular and in-vivo mechanics of the BFLH during the NHE. Thirteen participants (24.7 ± 3.7 years, 79.56 ± 7.89 kg, 177.40 ± 12.54 cm) performed three repetitions of the NHE at three horizontal planes (0°, 20° and −20°). Dynamic ultrasound of the dominant limb BFLH, surface electromyography (sEMG) of the contralateral hamstrings and sagittal plane motion data were simultaneously collected. Repeated measures analysis of variance with Bonferroni post hoc corrections were used on the in vivo mechanics and the kinematic and sEMG changes in performance of the NHE. Likely differences in ultrasound waveforms for the BFLH were determined. Significant and meaningful differences in kinematics and in vivo mechanics between NHE variations were observed. Non-significant differences were observed in sEMG measures between variations. Changes to the NHE performance angle manipulates the lever arm, increasing or decreasing the amount of force required by the hamstrings at any given muscle length, potentially changing the adaptive response when training at different planes and providing logical progressions ore regressions of the NHE. All NHE variations result in a similar magnitude of fascicle lengthening, which may indicate similar positive adaptations from the utilization of any variation. [ABSTRACT FROM AUTHOR]

Introduction: This study explored the relationship between first-time or repeat participation at a sports education camp and demographic variables of gender, age, race or ethnicity, measures of self-perception, body mass index (BMI), and physical activity in participants' communities. Methods: The study was a secondary data analysis of interview and BMI data for youths with visual impairments (i.e., those who are blind or have low vision) who attended a sports education camp in one of 12 states in the years 1989, 1996, and 2000-2010. Results: The short-term intervention model of a sports education camp had a positive effect on participants' perceptions of themselves. This result was more pronounced for boys and for youths with some usable vision. Involvement in a sports education camp did not tend to translate to increased involvement in sports in a student's community. The mean BMI of first-time participants was consistent across gender, race or ethnicity, and vision category, and the BMI of first-time participants tended to be higher according to the age of the participant. Discussion: The findings revealed that the short-term intervention model of a sports education camp is highly effective in increasing self-perception for youngsters with vision impairments. Implications for practitioners: For youths with visual impairments who might be experiencing reduced social interaction, decreased self-perception or increased BMI involvement in a sports education camp is a short-term intervention that can positively impact these effects.

Introduction: Youths with visual impairments (i.e., those who are blind or have low vision) often demonstrate reduced involvement in sports and related negative effects. This study looked at data from sports education camps to see whether involvement in this short-term intervention positively affected the performance of component sports skills such as running, throwing, and catching. Methods: This study is a secondary analysis of interview and performance data taken at sports education camps in one of 12 U.S. states in the years 1989, 1996, and 2000-2010. Data included questions about students' attitudes toward and involvement in physical activities and sports. Skill performance measured before and after each camp included standing long jump, overarm softball throw, underarm softball throw, and goalball throw. Results: First-time attendees at the sports education camps demonstrated significant improvement in overarm throw, underarm throw, and standing long jump. Boys had slightly greater increases in standing long jump and overarm throw, and girls had a larger increase in underarm throw. Participants who initially felt safe running improved more in overarm throw and those who initially felt unsafe running improved more in underarm throw and standing long jump. Girls and those who initially felt unsafe running had a significant increase in goalball throwing speed. Discussion: The sports education camp model of short-term intervention for basic sports skill instruction is highly effective in improving physical performance for students who are visually impaired. Implications for practitioners: Students with visual impairments who are demonstrating negative effects from not being active or involved in sports might positively benefit from involvement in a sports education camp.

Dependent variables commonly studied during countermovement vertical jump (CMVJ) tests largely stem from male-only studies despite females'distinct energy storage and reutilisation strategies. This could limit progress among females seeking increased CMVJ performance through targeted changes in certain variables. We explored relationships between CMVJ performance metrics (jump height, modified reactive strength index, jump power, and takeoff momentum) and (a) temporal and force application variables and (b) inter-limb force and yank (i.e., rate of force development) asymmetry in 31 recreationally active females. Participants performed eight CMVJs while ground reaction force (GRF) data were obtained. Pearson product-moment correlation coefficients assessed the strength and direction of the associations. Twenty-six significant relationships (r ≥ ±0.357; p < 0.05) were detected across the CMVJ performance variables. The significantly correlated variables were generally isolated to only one of the four performance metrics. Only the percentage of concentric phase inter-limb force asymmetry was significantly associated with CMVJ performance, specifically jump power and takeoff momentum. Coaches and physical performance professionals should be aware of popular strategy variables' association or lack of association with commonly studied performance metrics when seeking to understand or improve specific CMVJ jumping abilities in females. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the kinetics and kinematics across incremental loads with the push press (PP), push jerk (PJ), and split jerk (SJ). Eighteen resistance-trained men performed the 1 repetition maximum (1RM) tests (visit 1)3-7 days before an incremental loading protocol (60, 75, and 90% 1RM) of the 3 exercises (visit 2). Kinetics and kinematics were derived from force-time data and compared using a repeated-measures analysis of variance with load and exercise as within-subject factors. Dependent variables for the biomechanics assessment were categorized as output (power and impulse), driver (force and work), and strategy (displacement and duration) metrics. The interrepetition reliability was assessed using the intraclass correlation coefficient and coefficient of variation. The PP, PJ, and SJ 1RM performance were 89.7 ± 15.4, 95.6 ± 14.4, and 103.0 ± 16.9 kg, respectively. Driver, strategy, and outcome metrics displayed moderate-to-excellent (intraclass correlation coefficient: 0.58-0.98) reliability with acceptable variability (% co-efficient of variation: 2.02-10.00). Increased load resulted in significantly large increases in force, work, displacement, duration, power, and impulse (p < 0.001, ηp² = 0.534-0.903). Exercise selection had a significant and large effect on power, impulse, work, and force (p < 0.016, ηp² = 0.387-0.534). There was a significant and large effect of load x exercise interaction on work, displacement, and duration (p < 0.019, ηp² = 0.158-0.220). Practitioners are encouraged to use heavier loads (90 > 75 > 60% 1RM) during the SJ exercise to maximize output, driver, and strategy kinetics and kinematics. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is Available in the Text. The good morning is a barbell exercise that can be used to develop muscular strength and hypertrophy in the posterior chain (i.e., hamstring muscles, gluteal muscles, spinal erectors, calf complex). The exercise uses a hip hinge motion with the barbell positioned across the upper trapezius, offering lifters an alternative to more common posterior chain exercises, such as the Romanian deadlift. The good morning may be particularly beneficial for lifters with lower levels of grip strength or upper-limb injury, which may prevent using a clean or opposing grip. This review describes exercise techniques and discusses some of the underpinning principles of the exercise and potential applications in training.Video Abstract—http://links.lww.com/SCJ/A393. [ABSTRACT FROM AUTHOR]