Event history analysis of longitudinal data: a methodological application to sport sponsorship

Abstract

Despite its potential to make causal inferences and unearth insights related to between-subject variation over time, a small percentage of sport-related research is considered longitudinal in nature. One of the inherent challenges is that advanced quantitative methodologies, such as multi-level modelling approaches, are required to analyse such data. Therefore, this study is designed to assist those seeking to analyse longitudinal data by defining several important aspects of the event history analysis (EHA) methodology. The study’s goal was to conceptually demystify EHA by defining several fundamental concepts, including censoring, the survivor function and hazard function, through the application of EHA approaches to the durations of sport sponsorships. The authors conclude by demonstrating the implications of utilizing EHA approaches and identifying several potential applications of EHA for future sport-related research, with the goal of encouraging further sport scholarship utilizing approaches suitable for the analysis of longitudinal data.     

Reliability of accelerometry to assess impact loads of jumping and landing tasks

Overuse injuries, resulting from repetitive subacute impact loading, are a problem in high-performance sports. Monitoring of impact loading may aid in the prevention of these injuries. The current study aimed to establish the intra-day and inter-day reliability of a tri-axial accelerometer to assess impact loading during jumping and landing tasks. Twelve participants wore an accelerometer on their upper and lower back. They performed a continuous hopping task as well as drop landings and rebound jumps from three drop heights (37.5, 57.5 and 77.5 cm), peak resultant acceleration (PRA) was calculated for all tasks. The tasks were performed twice, one week apart at the same time of day. The difference in the mean, intra-class correlation coefficient, coefficient of variation and Cohen’s effect size were calculated as measures of reliability. PRA showed good intra-day reliability for the hopping task. Inter-day reliability of the PRA was moderate to good across all tasks. Reliability of PRA was slightly higher when accelerations were recorded on the lower back compared to the upper back. To assess impact loading, during continuous hopping, drop landings and rebound jumps, PRA recorded at both the upper and lower back appears to be a reliable measure.     

The impact of breathing on HRV measurements: Implications for the longitudinal follow-up of athletes

Abstract

The purpose of the present work was to compare daily variations of heart rate variability (HRV) parameters between controlled breathing (CB) and spontaneous breathing (SB) sessions during a longitudinal follow-up of athletes. HRV measurements were performed daily on 10 healthy male runners for 21 consecutive days. The signals were recorded during two successive randomised 5-minutes sessions. One session was performed in CB and the other in SB. The results showed significant differences between the two respiration methods in the temporal, nonlinear and frequency domains. However, significant correlations were observed between CB and SB (higher than 0.70 for RMSSD and SD1), demonstrating that during a longitudinal follow-up, these markers provide the same HRV variations regardless of breathing pattern. By contrast, independent day-to-day variations were observed with HF and LF/HF frequency markers, indicating no significant relationship between SB and CB data over time. Therefore, we consider that SB and CB may be used for HRV longitudinal follow-ups only for temporal and nonlinear markers. Indeed, the same daily increases and decreases were observed whatever the breathing method employed. Conversely, frequency markers did not provide the same variations between SB and CB and we propose that these indicators are not reliable enough to be used for day-to-day HRV monitoring.     

十一届全运会融入山东经济社会的战略思考

通过分析山东经济社会基础及十一届全运会对山东经济社会发展的推动作用,确定了举办十一届全运会的指导思想和总体目标。并围绕十一届全运会的阶段划分和主要任务,提出了山东省举办十一届全运会的战略对策。     

From novice to no know-how: a longitudinal study of implicit motor learning

The aim of this study was to ascertain whether the performances of implicit and explicit learners would converge over an extended period of learning. Participants practised a complex motor skill--golf putting--for 3000 trials, either with a concurrent secondary, tone-counting task (implicit learning) or without such a task (explicit learning). The cognitive demands of the secondary task were predicted to prevent the accumulation of verbalizable rules about the motor task. The implicit group reported significantly fewer rules than the explicit group on subsequent verbal protocols. The performance of the implicit group remained below that of the explicit group throughout the learning phase. However, no significant differences were found between groups during a delayed retention test. Additionally, for the participants in the explicit group only, a Reinvestment Scale score correlated positively with the number of rules accrued and negatively with overall putting performance during the learning phase. We use the results to argue against the excessive use of verbal instruction during skill acquisition, which might be unnecessary and ultimately might hamper performance under stressful conditions.     

Sports as a passport to success: life skill integration in a positive youth development program

Background: Sport-based youth development (SBYD) programs aim to teach life skills to youth within a physical activity context. An explicit objective of most SBYD programs is that youth learn to apply, or transfer, life skills beyond the sports program. Limited research has been conducted on the cognitive processes that help youth understand how life skills apply within and beyond sports.

Purpose: This study uses a conceptual framework on transfer of life skills to examine the role of life skills in an SBYD program. Research questions include: (1) how does the SBYD program integrate the teaching of life skills, (2) how do youth participants experience the life skills in the boxing program, and (3) how do youth participants perceive the life skills impact them beyond the program.

Methodology: This research took place at three community boxing academies in New Zealand. The three academies were selected because they are affiliated with a boxing program that is committed to implementing a life skills framework called the Passport to Success. Forty-one youth (31 boys, 10 girls) across the three sites participated in focus groups interviews about their experience in the program. Additionally, observations of program implementation documented the daily routines of each boxing academy. Using a qualitative case study design, inductive analysis and constant comparative methods were used to identify emergent themes.

Findings: Youth participants perceived life skills to be a foundational component of the boxing program. The life skills were presented to youth through the ‘Passport to Success’, a document featuring eight key life skills. The coaches focused on the Passport to Success in several ways, including setting an expectation that youth memorize the life skills to demonstrate their commitment. Several youth participants discussed learning valuable lessons around the life skills. Finally, youth were able to describe scenarios which demonstrated how the life skills connected with other areas of their lives.

Conclusion: Life skills implementation was guided by the Passport to Success and an expectation that youth develop positive relationships in the gym. A routine strategy for memorizing the Passport to Success provided a clear example of youth learning the meaning of life skills in the context of sports. The youth participants demonstrated cognitive connections in their explanation of the value of life skills beyond the boxing program. Using the conceptual framework on transfer [Jacobs and Wright 2018. “Transfer of Life Skills in Sport-Based Youth Development Programs: A Conceptual Framework Bridging Learning to Application.” Quest 70 (1): 81–99] helps to explain the cognitive connections youth participants make between life skills in a sports program and their application beyond sports.     

影片数据平滑方法的研究——利用动力学数据积分平滑运动学数据的方法

为减少影片数据平滑处理中误差。用 2 0 0Hz的高速摄影和 10 0 0Hz的Kistler测力台 ,对跳远运动员的起跳动作进行数据采集 ,研究运动员身体重心的速度和加速度的计算如何采用积分平滑的方法。结果表明利用动力学数据积分平滑运动学数据的方法可用来重心坐标的重构 ,所得的速度和加速度的结果更符合运动的力学规律 ;运动生物力学研究中应加强身体环节加速度的直接测量 ,运用积分平滑的方法可有效减少测量的误差。     

Preliminary development of a questionnaire to assess peer athlete mentoring functions: the Athlete Mentoring Questionnaire (AMQ)

Using a multiphase approach, the purpose of the present study was to develop a psychometrically sound questionnaire to measure protégés’ perceptions of peer athlete mentoring functions. Phase 1 consisted of three stages: (a) item development, (b) assessment of content validity via think-aloud interviews with peer mentored athletes, and (c) assessment of content validity via an expert rating panel. In phase 2, 377 Canadian National team and varsity athletes who were peer mentored completed an initial 42-item version of the Athlete Mentoring Questionnaire (AMQ) and its factor structure was examined using confirmatory factor analysis (CFA), exploratory structural equation modeling (ESEM), and hierarchical ESEM (ESEM-within-CFA). Measurement invariance testing was also performed in phase 2. The final version of the AMQ contains 34 items that measure six peer athlete mentoring functions. It is hoped that the development of the AMQ will spur research in the emerging area of peer athlete mentoring.     

The impact of data reduction on the intra-trial reliability of a typical measure of lower limb musculoskeletal stiffness

Double-leg repeated jumping tasks are commonly used as measures of lower limb stiffness in exercise science research. Within similar stiffness calculations, variation in data-reduction criteria exists. The impact of these varied data-reduction methods on stiffness measures is unknown. Sixteen adolescent female participants from varied physical activity backgrounds performed 15 self-paced, bent-knee continuous jumps (CJb) on two force plates. Leg stiffness was calculated as the ratio of the peak force and the centre of mass displacement for each contact. Using combinations of criteria based on previous literature, 83 data-reduction methods were applied to the raw data. Data reduction suitability was assessed based on intra-trial reliability, the number of participants excluded and the average contacts excluded. Four data-reduction methods were deemed suitable for use with adolescent female populations, with three consecutive contacts within 1 SD of the average jump frequency considered optimal. The average individual stiffness values were not greatly influenced by the data-reduction method; however, for a single participant, a stiffness change of up to 6 kN · m^?1 (30%) was observed. The role and potential impact of data-reduction methods used to evaluate measures of lower limb stiffness during repeated jumping tasks warrants consideration.     

Analyzing the impact of sport infrastructure on sport participation using geo-coded data: Evidence from multi-level models

Sport policies aiming at increasing mass participation and club participation have stressed the importance of sport infrastructure. Previous research has mainly analyzed the influence of individual factors (age, income, etc.) on sport participation. Although a few studies have dealt with the impact of sport facilities on sport participation, some methodological shortcomings can be observed regarding the integration of sport infrastructure into the research design. Oftentimes, subjective measures of infrastructure are employed, leading to biased results, for example inactive people have a worse perception of the actual supply of facilities. In fact it is important to measure the available sport infrastructure objectively using a quantitative approach and integrate it into statistical models. Therefore, the purpose of this study is to analyze the impact of individual and infrastructure variables on sport participation in general and in sport clubs using geo-coded data following a multi-level design. For this purpose, both primary data (individual level) and secondary data (infrastructure level) were collected in the city of Munich, Germany. A telephone survey of the resident population was carried out (n = 11,175) and secondary data on the available sport infrastructure in Munich were collected. Both datasets were geo-coded using Gauss–Krueger coordinates and integrated into multi-level analyses. The multi-level models show that swimming pools are of particular importance for sport participation in general and sport fields for participation in sport clubs. Challenges and implications for a more holistic modeling of sport participation including infrastructure variables are discussed.     

Through the years: a longitudinal study of physical education teachers from a research-based preparation program

This study investigated factors that enhanced and constrained the career development of six teachers, who had graduated from the same university teacher education program, in their induction years (Woods & Earls, 1995) and again later in their career cycles. Three participants were physical education teachers (PETs), and three were former physical education teachers (FPETs). Fessler's (1985) Teacher Career Stage Model provided the theoretical framework. Data sources were: interviews with teachers and their teacher educators and direct observations of lessons. Results indicated that the PETs continued to have skill development as their primary teaching objective. The teachers maintained many of their teaching skills, and shifted between the career cycles of "competency building" and "enthusiastic and growing." All three FPETs left their physical education positions during the career frustration stage and at the time of publication were in the career exit stage.     

Using micro-sensor data to quantify macro kinematics of classical cross-country skiing during on-snow training

Abstract

Micro-sensors were used to quantify macro kinematics of classical cross-country skiing techniques and measure cycle rates and cycle lengths during on-snow training. Data were collected from seven national level participants skiing at two submaximal intensities while wearing a micro-sensor unit (MinimaxX^?). Algorithms were developed identifying double poling (DP), diagonal striding (DS), kick-double poling (KDP), tucking (Tuck), and turning (Turn). Technique duration (T-time), cycle rates, and cycle counts were compared to video-derived data to assess system accuracy. There was good reliability between micro-sensor and video calculated cycle rates for DP, DS, and KDP, with small mean differences (Mdiff% = ?0.2 ± 3.2, ?1.5 ± 2.2 and ?1.4 ± 6.2) and trivial to small effect sizes (ES = 0.20, 0.30 and 0.13). Very strong correlations were observed for DP, DS, and KDP for T-time (r = 0.87–0.99) and cycle count (r = 0.87–0.99), while mean values were under-reported by the micro-sensor. Incorrect Turn detection was a major factor in technique cycle misclassification. Data presented highlight the potential of automated ski technique classification in cross-country skiing research. With further refinement, this approach will allow many applied questions associated with pacing, fatigue, technique selection and power output during training and competition to be answered.     

Validity and reliability of a low-cost dynamometer to assess maximal isometric strength of upper limb

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.     

Development and validation of an inventory to assess conflict in sport teams: the Group Conflict Questionnaire

Abstract

The purpose of the study was to develop and validate a conceptually and psychometrically sound conflict questionnaire for sport. The development process involved 3 phases: (a) a qualitative phase, (b) a content and factorial validity phase and (c) a construct validity phase. A total of 50 items were generated and sent to 6 experts to determine content validity. Through this process, 25 items were retained and administered to a sample of athletes (n = 437) to determine factorial validity. Based on these results, a second sample (n = 305) was administered the 14-item version of the Group Conflict Questionnaire along with the Group Environment Questionnaire, the Athlete Satisfaction Questionnaire and the Passion Scale to test convergent, discriminant and known-group difference validity. Cross-validation from both samples via confirmatory factor analysis yielded moderate-to-acceptable model fit, thus supporting factorial validity for the 14-item version. Additionally, initial support for convergent validity and known-group difference validity and partial support for discriminant validity were found. A sport-specific conflict questionnaire is now available for researchers to utilise. Results and research implications are discussed.     

Validity of a trunk-mounted accelerometer to assess peak accelerations during walking,jogging and running

Abstract

The purpose of this study was to validate peak acceleration data from an accelerometer contained within a wearable tracking device while walking, jogging and running. Thirty-nine participants walked, jogged and ran on a treadmill while 10 peak accelerations per movement were obtained (n = 390). A single triaxial accelerometer measured resultant acceleration during all movements. To provide a criterion measure of acceleration, a 12-camera motion analysis (MA) system tracked the position of a retro-reflective marker affixed to the wearable tracking device. Peak raw acceleration recorded by the accelerometer significantly overestimated peak MA acceleration (P < 0.01). Filtering accelerometer data improved the relationship with the MA system (P < 0.01). However, only the 10 Hz and 8 Hz cut-off frequencies significantly reduced the errors found. The walk movement demonstrated the highest accuracy, agreement and precision and the lowest relative errors. Linear increases in error were observed for jog compared with walk and for run compared to both other movements. As the magnitude of acceleration increased, the strength of the relationship between the accelerometer and the criterion measure decreased. These results indicate that filtered accelerometer data provide an acceptable means of assessing peak accelerations, in particular for walking and jogging.     

Validity of a contact mat and accelerometric system to assess countermovement jump from flight time

Countermovement jump (CMJ) height is an important parameter in physical performance. This study compared CMJ height measured using ChronoJump contact mat (CJ) and Myotest accelerometer (MT) systems with a force platform (FP). Thirty recreationally active adults (32.1 ± 10.4 years, 75.9 ± 12.0 kg, 173.2 ± 6.3 cm) completed a CMJ protocol where height was simultaneously recorded using the three systems. CJ and MT measures were strongly and significant correlated (r = 0.65, 0.66, respectively; p < 0.05) with FP. CJ-derived measures were not significantly different to FP measures (p > 0.05), yet MT-derived measures were significantly different from those obtained using the FP (p < 0.05). Systematic bias was observed between FP and the CJ and between FP and MT. This study demonstrates the validity of CJ and MT systems for the assessment of CMJ height. Systematic bias and between-device differences in measurement should be considered when interpreting and comparing data from these devices.     

An occlusion paradigm to assess the importance of the timing of the quiet eye fixation

Abstract

The aim of the study was to explore the significance of the ‘timing’ of the quiet eye (QE), and the relative importance of late (online control) or early (pre-programming) visual information for accuracy. Twenty-seven skilled golfers completed a putting task using an occlusion paradigm with three conditions: early (prior to backswing), late (during putter stroke), and no (control) occlusion of vision. Performance, QE, and kinematic variables relating to the swing were measured. Results revealed that providing only early visual information (occluding late visual information) had a significant detrimental effect on performance and kinematic measures, compared to the control condition (no occlusion), despite QE durations being maintained. Conversely, providing only late visual information (occluding early visual information) was not significantly detrimental to performance or kinematics, with results similar to those in the control condition. These findings imply that the visual information extracted during movement execution – the late proportion of the QE – is critical when golf putting. The results challenge the predominant view that the QE serves only a pre-programming function. We propose that the different proportions of the QE (before and during movement) may serve different functions in supporting accuracy in golf putting.     

From novice to no know-how: A longitudinal study of implicit motor learning

The aim of this study was to ascertain whether the performances of implicit and explicit learners would converge over an extended period of learning. Participants practised a complex motor skill - golf putting - for 3000 trials, either with a concurrent secondary, tone-counting task (implicit learning) or without such a task (explicit learning). The cognitive demands of the secondary task were predicted to prevent the accumulation of verbalizable rules about the motor task. The implicit group reported significantly fewer rules than the explicit group on subsequent verbal protocols. The performance of the implicit group remained below that of the explicit group throughout the learning phase. However, no significant differences were found between groups during a delayed retention test. Additionally, for the participants in the explicit group only, a Reinvestment Scale score correlated positively with the number of rules accrued and negatively with overall putting performance during the learning phase. We use the results to argue against the excessive use of verbal instruction during skill acquisition, which might be unnecessary and ultimately might hamper performance under stressful conditions.     

Validity and feasibility of an obstacle course to assess fundamental movement skills in a pre-school setting

Failure to master age-appropriate fundamental movement skills (FMS) at a young age can limit motor skill competence affecting health. Assessments often have issues with feasibility and implementation in a field setting. As such, the purpose of this study was to investigate the validity and feasibility of the Athletic Skills Track (AST), in a pre-school setting. For the validation study sixty-five 3–6 year old children (25 boys and 40 girls) from five pre-schools across Adelaide, Australia participated. Correlations and linear regression analysis (adjusted for age and gender) were used to investigate the association between the time to complete the AST and the raw score of the Test of Gross Motor Development 2 (TGMD-2). For the feasibility study pre-school staff completed a semi-structured interview regarding the feasibility of the AST. The AST took less than a minute per child and the TGMD-2 around 20 minutes for two children. There was a strong negative correlation (r = ?0.63, p < 0.01) between the AST scores and the TGMD-2 scores. All five staff reported strengths of the AST to be its short administration time, setup and appropriateness. These results suggest that the AST could be a feasible and valid method of FMS assessment in Australian pre-schools.