The Dutch motor skills assessment as tool for talent development in table tennis: a reproducibility and validity study

A motor skills assessment could be helpful in talent development by estimating essential perceptuo-motor skills of young players, which are considered requisite to develop excellent technical and tactical qualities. The Netherlands Table Tennis Association uses a motor skills assessment in their talent development programme consisting of eight items measuring perceptuo-motor skills specific to table tennis under varying conditions. This study aimed to investigate this assessment regarding its reproducibility, internal consistency, underlying dimensions and concurrent validity in 113 young table tennis players (6–10 years). Intraclass correlation coefficients of six test items met the criteria of 0.7 with coefficients of variation between 3% and 8%. Cronbach’s alpha valued 0.853 for internal consistency. The principal components analysis distinguished two conceptually meaningful factors: “ball control” and “gross motor function.” Concurrent validity analyses demonstrated moderate associations between the motor skills assessment’s results and national ranking; boys r = ?0.53 (P < 0.001) and girls r = ?0.45 (P = 0.015). In conclusion, this evaluation demonstrated six test items with acceptable reproducibility, good internal consistency and good prospects for validity. Two test items need revision to upgrade reproducibility. Since the motor skills assessment seems to be a reproducible, objective part of a talent development programme, more longitudinal studies are required to investigate its predictive validity.     

Development of a Notational Analysis System for Selected Soccer Skills of a Women's College Team

The purposes of this study were to develop a notational system to evaluate passing, dribbling, first touch, and individual defensive skills as they relate to success during women's soccer games and to develop a statistical model to weigh the importance of each skill on creating scoring opportunities. Sequences of skills in ten games of a National Collegiate Athletic Association Division I intercollegiate women's soccer team were coded using well defined performance scores and outcomes. The notational analysis system was highly reliable as demonstrated by Spearman's rank correlations (>.98) between the first and second notation of three games for all four skills. The importance scores calculated from a Bayesian model demonstrated that dribbling (.0127) was the most important skill on creating scoring opportunities, followed by first touch (.0079), passing (.0075), and individual defense (.0050). The notational system developed from this study provides coaches with reliable and objective information to improve practice planning and optimize performance.     

Emotion regulation and motor performance: an integrated review and proposal of the Temporal Influence Model of Emotion Regulation (TIMER)

ABSTRACT

Adaptive regulation of emotions is imperative for successful sport performance. However, the lion’s share of mainstream emotion regulation (ER) literature is founded on perspectives prioritising mental health, not performance. Consequently, ER strategies are predominantly classified as adaptive or maladaptive based on effectiveness in achieving targeted mental health outcomes. These conventional mental health classifications can catalyse misapplication of ER strategies within sport and other motor performance contexts when (1) ER motives are instrumentally directed towards performance enhancement and (2) Minimal consideration is given to the consequences of ER on the coordination and execution of motor actions. Herein, we review the current state of relevant ER research within and outside of sport contexts. We also present a novel conceptual framework, the Temporal Influence Model of Emotion Regulation (TIMER). TIMER proposes that ER strategies exert distinct, temporally dependent demands upon perceptual-cognitive and motoric resources. These unique regulatory profiles influence subsequent motor performance outcomes. Critically, the degree to which regulatory strategies are appropriate or ideal varies given environmental constraints along with performers’ affective and performance goals. The model includes testable hypotheses to guide theoretical and applied research in the domain of ER within sport and other motor performance contexts.     

Assessing rugby place kick performance from initial ball flight kinematics: development,validation and application of a new measure

The appropriate determination of performance outcome is critical when appraising a performer’s technique. Previous studies of rugby place kicking technique have typically assessed performance based on ball velocity, but this is not the sole requirement. Therefore, a mathematical model of rugby place kick ball flight was developed to yield a single measure more representative of true performance. The model, which requires only initial ball flight kinematics, was calibrated and validated using empirical place kick data, and found to predict ball position with a mean error of 4.0% after 22 m of ball flight. The model was then applied to the performances of 33 place kickers. The predicted maximum distance, a single performance measure which accounted for initial ball velocity magnitude and direction, and spin, was determined using the model and was compared against ball velocity magnitude. A moderate association in the rank-order of the kicks between these two measures (ρ = 0.52) revealed that the relative success of the kicks would be assessed differently with each measure. The developed model provides a representative measure of place kick performance that is understandable for coaches, and can be used to predict changes in performance outcome under different ball launch or environmental conditions.     

Machine and deep learning for sport-specific movement recognition: a systematic review of model development and performance

Objective assessment of an athlete’s performance is of importance in elite sports to facilitate detailed analysis. The implementation of automated detection and recognition of sport-specific movements overcomes the limitations associated with manual performance analysis methods. The object of this study was to systematically review the literature on machine and deep learning for sport-specific movement recognition using inertial measurement unit (IMU) and, or computer vision data inputs. A search of multiple databases was undertaken. Included studies must have investigated a sport-specific movement and analysed via machine or deep learning methods for model development. A total of 52 studies met the inclusion and exclusion criteria. Data pre-processing, processing, model development and evaluation methods varied across the studies. Model development for movement recognition were predominantly undertaken using supervised classification approaches. A kernel form of the Support Vector Machine algorithm was used in 53% of IMU and 50% of vision-based studies. Twelve studies used a deep learning method as a form of Convolutional Neural Network algorithm and one study also adopted a Long Short Term Memory architecture in their model. The adaptation of experimental set-up, data pre-processing, and model development methods are best considered in relation to the characteristics of the targeted sports movement(s).     

Validity and reliability of a new field test (Carminatti's test) for soccer players compared with laboratory-based measures

Abstract

The aim of this study was to assess the validity (Study 1) and reliability (Study 2) of a novel intermittent running test (Carminatti's test) for physiological assessment of soccer players. In Study 1, 28 players performed Carminatti's test, a repeated sprint ability test, and an intermittent treadmill test. In Study 2, 24 players performed Carminatti's test twice within 72 h to determine test–retest reliability. Carminatti's test required the participants to complete repeated bouts of 5 × 12 s shuttle running at progressively faster speeds until volitional exhaustion. The 12 s bouts were separated by 6 s recovery periods, making each stage 90 s in duration. The initial running distance was set at 15 m and was increased by 1 m at each stage (90 s). The repeated sprint ability test required the participants to perform 7 × 34.2 m maximal effort sprints separated by 25 s recovery. During the intermittent treadmill test, the initial velocity of 9.0 km · h^?1 was increased by 1.2 km · h^?1 every 3 min until volitional exhaustion. No significant difference (P > 0.05) was observed between Carminatti's test peak running velocity and speed at VO_2max (v-VO_2max). Peak running velocity in Carminatti's test was strongly correlated with v-VO_2max (r = 0.74, P < 0.01), and highly associated with velocity at the onset of blood lactate accumulation (r = 0.63, P < 0.01). Mean sprint time was strongly associated with peak running velocity in Carminatti's test (r = ?0.71, P < 0.01). The intraclass correlation was 0.94 with a coefficient of variation of 1.4%. In conclusion, Carminatti's test appears to be avalid and reliable measure of physical fitness and of the ability to perform intermittent high-intensity exercise in soccer players.     

Concurrent criterion validity of a novel portable motion analysis system for assessing the landing error scoring system (LESS) test

The landing error scoring system (LESS) assesses the quality of a landing after a jump. The quality of the jump is usually evaluated using a three-dimensional (3-D) motion analysis system or a two-dimensional (2-D) video analysis visually rated by a clinician. However, both methods have disadvantages. The aim of this study was to examine the concurrent validity of a novel portable motion analysis system (‘PhysiMax System’) in assessing the LESS score by comparing it to video analysis. The study population included 48 healthy participants (28.45 ± 5.61 years), each performing the LESS test while two video cameras and the ‘PhysiMax’ simultaneously recorded the jump. The ‘Physimax’ system automatically evaluated the LESS. Subsequently, the examiners scored the test by viewing the video recordings, blinded to the ‘PhysiMax’ results. The mean LESS score, using the video recordings and the ‘PhysiMax’ was 4.77 (±2.29) and 5.15 (±2.58), respectively, (ICC = 0.80, 95% confidence intervals 0.65–0.87), mean absolute differences 1.13 (95% confidence intervals; 0.79–1.46). The results indicate a high consensus between the methods of measurement. The ‘Physimax’ system’s main advantages are portability, objective evaluation and immediate availability of results. The system can be used by athletic trainers and physiotherapists in the clinic and in the field for jumping assessment.