Reliability, interrelationships, and minimal detectable changes of strength and power metrics among well-trained rugby sevens players.

Despite the importance of strength and power in rugby skills and match outcomes, there exists a noticeable gap in the measurement consistency and estimation of a true change of typical assessments designed to assess these qualities. To address this gap, we investigated the between-session reliability, interrelationships, and minimal detectable changes (MDC) of commonly used strength and power measures in team sports. Sixteen national-level rugby 7 s players were tested on two occasions, one week apart. Both the best and average (of 2-3 trials) peak force, peak power, height, distance, and/or strength indices during countermovement jump (CMJ), drop jump (DJ), isometric mid-thigh pull (IMTP), plyometric push-up (PPU), and standing long jump (SLJ) were obtained. Furthermore, one-repetition maximum (1RM) strength for bench press and back squat, reactive strength index, and dynamic strength index were also determined. Reliability was assessed using intraclass correlation coefficients (ICC) and coefficients of variation (CV), and used for MDC calculations, and interrelationships between variables were determined using correlation coefficients. Reliability was excellent for bench press, back squat, and SLJ (ICCs > 0.91); high to excellent for IMTP peak force, all CMJ, and DJ (except best DJ height and contact time), and PPU peak force parameters (ICCs > 0.78), with < 10% CVs (except PPU peak power). MDCs were generally smaller for average than best values. Large to very large relationships (r = 0.60 to 0.85) were observed between bench press, back squat, and IMTP with selected parameters of CMJ and PPU (p < 0.05), but not in DJ and SLJ. In conclusion, selected measures of strength and power displayed high to excellent reproducibility, with average values (rather than best) offering more stable assessments, and "smaller" MDCs. Based upon the relationships, it can be inferred that maximising strength would likely contribute to enhanced explosive performance.

Validación del California Bullying Victimization Scale en una muestra de universitarios mexicanos / Validation of the California Bullying Victimization Scale in a sample of Mexican university students / Validação da Escala de Vitimização de Bullying da Califórnia em uma amostra de estudantes universitários mexicanos

Muchos instrumentos de bullying no evalúan los tres componentes teóricos que lo conforman; y solo algunos instrumentos abordan el desbalance de poder. México no es la excepción. Es por ello que el propósito de este estudio es validar el California Bullying Victimization Scale (CBVS) en una muestra de estudiantes universitarios de México, al ser un instrumento que sí contempla todos sus componentes. Participaron 1116 estudiantes universitarios mayores de 18 años. Se aplicó la versión en español del CBVS junto al cuestionario de agresión reactiva y proactiva, el Inventario de Depresión de Beck y la Escala de Malestar Psicológico de Kessler. Se analizó la confiabilidad, y su estructura, así como pruebas de asociación entre el CBVS y las otras escalas. El instrumento presentó una confiabilidad alta según el alfa de Cronbach y omega de McDonald. Se encontró una estructura bifactorial, que agrupa los reactivos en violencia directa e indirecta. El instrumento presentó evidencia de validez de constructo al tener asociaciones con la agresión, la satisfacción académica, la ansiedad y el malestar psicológico. El instrumento presentó propiedades psicométricas adecuadas tanto de confiabilidad como de validez, y la estructura del test es consistente con la teoría de agresión directa e indirecta del bullying.

Many bullying instruments do not assess the three theoretical components of bullying, and only a few instruments address the imbalance of power. Mexico is no exception. Therefore, the purpose of this study is to validate the California Bullying Victimization Scale (CBVS) in a sample of Mexican university students, as it is an instrument that does address all its components. A total of 1116 university students over 18 years of age participated. The Spanish version of the CBVS was administered together with the reactive and proactive aggression questionnaire, the Beck Depression Inventory and the Kessler Psychological Distress Scale. Reliability and structure were analyzed, as well as tests of association between the CBVS and the other scales. The instrument presented high reliability according to Cronbach's alpha and McDonald's omega. A bifactor structure was found, grouping the items into direct and indirect violence. The instrument presented evidence of construct validity by having associations with aggression, academic satisfaction, anxiety and psychological distress. The instrument presented adequate psychometric properties of reliability and validity, and the structure of the test is consistent with the direct and indirect aggression theory of bullying.

Muitos instrumentos de bullying não avaliam os três componentes teóricos do bullying; e apenas alguns poucos instrumentos abordam o desequilíbrio de poder. O México não é exceção. Portanto, o objetivo deste estudo é validar a Escala de Vítima de Bullying da Califórnia (CBVS) em uma amostra de estudantes universitários mexicanos, pois trata-se de um instrumento que trata de todos os seus componentes. Um total de 1116 estudantes universitários com mais de 18 anos de idade participaram. A versão espanhola da CBVS foi administrada juntamente com o questionário de agressão reativo e proativo, o Inventário de Depressão Beck e a Escala de Angústia Psicológica Kessler. Foram analisadas a confiabilidade e a estrutura, bem como os testes de associação entre a CBVS e as outras escalas. O instrumento demonstrou alta confiabilidade de acordo com o alfa do Cronbach e o ômega do McDonald>s. Foi encontrada uma estrutura de bifator, agrupando os itens em violência direta e indireta. O instrumento mostrou evidência de validade construtiva por ter associações com agressão, satisfação acadêmica, ansiedade e angústia psicológica. O instrumento apresentou propriedades psicométricas adequadas tanto de confiabilidade quanto de validade, e a estrutura do teste é consistente com a teoria de agressão direta e indireta do bullying.

Measuring the Hip Adductor to Abductor Strength Ratio in Ice Hockey and Soccer Players: A Critically Appraised Topic.

Clinical Scenario: Ice hockey and soccer are both dynamic sports that involve continuous, unpredictable play. These athletes consistently demonstrate higher rates of groin strains compared with other contact sports. Measuring the hip adductor/abductor ratio has the potential to expose at-risk players, reduce injury rates, and preserve groin health in players with chronic strains. Focused Clinical Question: What is the clinical utility of measuring the hip adductor/abductor ratio for preseason and in-season ice hockey and soccer players? Summary of Key Findings: Three studies, all of which were prospective cohort designs, were included. One study involved assessing preseason strength and flexibility as a risk factor for adductor strains in professional ice hockey players. Another study performed with the same professional hockey team used preseason hip adductor/abductor strength ratios to screen for those players who would benefit from a strengthening intervention aimed at reducing the incidence of adductor strains. The final study, which was performed in elite U17 soccer players, assessed the effectiveness of monthly in-season strength monitoring as a guide to trigger in-season interventions to decrease injury incidence. Clinical Bottom Line: Measuring the hip adductor/abductor strength ratio in hockey and soccer players can be a beneficial preseason and in-season tool to predict future groin strain risk and screen for athletes who might benefit from a strengthening intervention. Strength of Recommendation: Level 3 evidence exists to support monitoring the hip adductor/abductor strength ratio to assess and reduce the risk of adductor strains in ice hockey and soccer players.

A Critically Appraised Topic on the Tuck Jump Assessment: Does the Tuck Jump Assessment Demonstrate Interrater and Intrarater Reliability in Healthy Individuals?

Clinical Scenario: Lower-extremity injuries in the United States costs millions of dollars each year. Athletes should be screened for neuromuscular deficits and trained to correct them. The tuck jump assessment (TJA) is a plyometric tool that can be used with athletes. Clinical Question: Does the TJA demonstrate both interrater and intrarater reliability in healthy individuals? Summary of Key Findings: Four of the 5 articles included in this critically appraised topic showed good to excellent reliability; however, caution should be taken in interpreting these results. Although composite scores of the TJA were found to be reliable, individual flaws do not demonstrate reliability on their own, with the exception of knee valgus at landing. Aspects of the TJA itself, including rater training, scoring system, playback speed, volume, and number of views allotted, need to be standardized before the reliability of this clinical assessment can be further researched. Clinical Bottom Line: The TJA has shown varying levels of reliability, from poor to excellent, for both interrater and intrarater reliability, given current research. Strength of Recommendation: According to the Centre for Evidence Based Medicine levels of evidence, there is level 2b evidence for research into the reliability of the TJA. This evidence has been demonstrated in elite, adolescent, and college-level athletics in the United Kingdom, Spain, and the United States. The recommendation of level 2b was chosen because these studies utilized cohort design for interrater and intrarater reliability across populations. An overall grade of B was recommended because there were consistent level 2 studies.

Reliability of 5 Novel Reaction Time and Cognitive Load Protocols.

CONTEXT: Reaction time (RT) is crucial to athletic performance. Therefore, when returning athletes to play following injury, it is important to evaluate RT characteristics ensuring a safe return. The Dynavision D2® system may be utilized as an assessment and rehabilitation aid in the determination of RT under various levels of cognitive load. Previous research has demonstrated good reliability of simple protocols when assessed following a 24- to 48-hour test-retest window. Expanding reliable test-retest intervals may further refine novel RT protocols for use as a diagnostic and rehabilitation tool. OBJECTIVE: To investigate the test-retest reliability of a battery of 5 novel RT protocols at different time intervals. DESIGN: Repeated measures/reliability. SETTING: Interdisciplinary sports medicine research laboratory. PARTICIPANTS: Thirty healthy individuals. METHODS: Participants completed a battery of protocols increasing in difficulty in terms of reaction speed requirement and cognitive load. Prior to testing, participants were provided 3 familiarization trials. All protocols required participants to hit as many lights as quickly as possible in 60 seconds. After completing the initial testing session (session 1), participants waited 1 hour before completing the second session (session 2). Approximately 2 weeks later (average 14 [4] d), the participants completed the same battery of tasks for the third session (session 3). MAIN OUTCOME MEASURES: The intraclass correlation coefficient, standard error of measurement, minimal detectable change, and repeated-measures analysis of variance were calculated for RT. RESULTS: The intraclass correlation coefficient values for each of the 5 protocols illustrated good to excellent reliability between sessions 1, 2, and 3 (.75-.90). There were no significant differences across time points (F < 0.105, P > .05). CONCLUSIONS: The 1-hour and 14-day test-retest intervals are reliable for clinical assessment, expanding the time frames previously reported in the literature of when assessments can be completed reliably. This study provides novel protocols that challenge cognition in unique ways.

Testing Postural Stability: Are the Star Excursion Balance Test and Biodex Balance System Limits of Stability Tests Consistent?

There are a variety of options to test postural stability; however many physical tests lack validity information. Two tests of postural stability - the Star Excursion Balance Test (SEBT) and Biodex Balance System Limits of Stability Test (LOS) - were examined to determine if similar components of balance were measured. Healthy adults (n=31) completed the LOS (levels 6 and 12) and SEBT (both legs). SEBT directions were offset by 180° to approximate LOS direction. Correlations and partial correlations controlling for height were analyzed. Correlations were significant for SEBT 45° and LOS back-left (6: r=-0.41; 12: r=-0.42; p<0.05), SEBT 90° and LOS 6 left (r=-0.51, p<0.05), SEBT 135(o) and LOS 6 front-left (r=-0.53, p<0.05), SEBT overall and LOS 6 overall (r=-0.43, p<0.05). Partial correlations were significant for SEBT 90° and LOS 6 left (rSEBT,LOS·H=-0.45, p<0.05) and SEBT 135° and LOS 6 front-left (rSEBT,LOS·H=-0.51, p<0.05), and SEBT overall and LOS 6 overall (rSEBT,LOS·H=-0.37, p<0.05). These findings indicate the tests seem to assess different components of balance. Research is needed to determine and define what specific components of balance are being assessed. Care must be taken when choosing balance tests to best match the test to the purpose of testing (fall risk, athletic performance, etc.).