Publications by authors named "Werner F Helsen"

Amatori, S, Helsen, WF, Baldari, C, Serra, T, Belli, A, Guidetti, L, Rocchi, MBL, Sisti, D, and Perroni, F. High-speed efforts of elite association football referees in national and international matches. J Strength Cond Res 38(8): e417-e422, 2024-Field referees (FRs) need to move throughout the pitch to identify any infringements of the game's laws.

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Introduction: Youth soccer academies are challenged with the constant recruitment process of young talented players to select those who will achieve long-term success as an athlete. Youth soccer academies strive to enhance the physical and technical skill development as well as personality development of talented players because psychological characteristics play a crucial role in players' future success in their transition to professional soccer. The least mature players and relatively young players may have a greater need to possess superior technical/tactical or psycho-behavioral skills than those relatively older counterparts because of the higher selection rates of early maturing players.

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The purpose of this study was to understand the contribution of each performance indicator to evaluate match performance of football referees. Thirty-four elite Referee Match Observers (RMOs) from the Portuguese FA participated voluntarily in the study. From the official assessment sheet of each game, the referee's game score was categorized in two groups according to referee's game score: i) Referees with a Low Score (LFS) and ii) Referees with High Score (HFS).

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This study investigated the effects of 10 weeks of recreational football training on the leg-extensor force-velocity (F-V) profile in 55- to 70-year-old adults. Simultaneous effects on functional capacity, body composition and endurance exercise capacity were examined. Forty participants (age 63.

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Introduction: The ability to perform optimally under pressure is critical across many occupations, including the military, first responders, and competitive sport. Despite recognition that such performance depends on a range of cognitive factors, how common these factors are across performance domains remains unclear. The current study sought to integrate existing knowledge in the performance field in the form of a transdisciplinary expert consensus on the cognitive mechanisms that underlie performance under pressure.

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Purpose: To examine the utility of a standardized small-sided game (SSG) for monitoring within-player changes in mean exercise heart rate (HRex) when compared with a submaximal interval shuttle-run test (ISRT).

Methods: Thirty-six elite youth football players (17 [1] y) took part in 6 test sessions across an in-season period (every 4 wk). Sessions consisted of the ISRT (20-m shuttles, 30″:15″ work:rest ratio, 70% maximal ISRT) followed by an SSG (7v7, 80 × 56 m, 6 min).

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Purpose: To examine the utility of differential ratings of perceived exertion (dRPE) for monitoring internal intensity and load in association football.

Methods: Data were collected from 2 elite senior male football teams during 1 season (N = 55). External intensity and load data (duration × intensity) were collected during each training and match session using electronic performance and tracking systems.

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The rating of perceived exertion method (RPE) allows to describe training intensity in a single value. To better understand the underlying components, the separate rating of perceived breathlessness (RPE-B) and leg-muscle exertion (RPE-L) has been proposed. Here we hypothesised that the separation between the two components may (partly) be determined by the impacts on the lower extremities.

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Relative age selection bias persists within all major soccer leagues and youth soccer academies across the globe, with the relative age effect (RAE) being typically characterized as the over selection of relatively older players (who have sometimes also been shown to be early maturing). The aim of this study was to examine if a new allocation method (i) eliminates the RAE, and (ii) reduces the presence of any additional maturity-related differences in anthropometric and physical fitness characteristics which may exist between players within the same selection category. In the first phase, 1,003 academy soccer players [under (U) 9-16] from 23 UK professional soccer clubs were sampled and a clear RAE per birth quarter (Q) was observed for the overall sample (Q1 = 45.

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This study examines differences in weekly load between the first (FT) and the under 19 team (U19) within a professional football setting. Data were collected in 11 FT and 9 U19 players (2016-2017 season). FT data was divided into weeks with (FT-M1) or without (FT-M0) a mid-week match.

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The description of current load monitoring practices may serve to highlight developmental needs for both the training ground, academia and related industries. While previous studies described these practices in elite men's football, no study has provided an overview of load monitoring practices in elite women's football. Given the clear organizational differences (i.

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Load monitoring is considered important to manage the physical training process in team sports such as Association Football. Previous studies have described the load monitoring practices of elite English football clubs and clubs with an established sports-science department. An examination of a broader international sample is currently not available.

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Despite various solutions proposed to solve the relative age effect (RAE), it is still a major problem confounding talent identification and selection processes. In the first phase, we sampled 302 under 7-21 academy soccer players from two Belgian professional soccer clubs to explore the potential of a new approach to solve the inequalities resulting from relative age- and maturity-related bias. This approach allocates players into four discrete quartile groups based on the midway point of their chronological and estimated developmental (ED) birth dates (calculated using the growth curves for stature of Belgian youth).

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Published reports suggest that nonoptimal visual search behavior is associated with false negatives in chest x-ray interpretation. Eye movement modeling example (EMME)-based training interventions, that is, interventions showing models of visual search to trainees, have been shown to improve visual search as well as task accuracy. We examined the detection of focal lung pathology on chest x-rays before and after two different EMME training interventions that have been shown to be efficient: (i) an EMME showing moving fixations on a blurred background (spotlight group) and (ii) an EMME showing moving fixations on a nonblurred background (circle group).

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The effects of acute strength training on balance control were studied in healthy older human men (age-range 60-77y). Participants performed the Tandem Romberg Stance while completing an attention demanding cognitive task (Mathematical Counting) before and after a single acute strength training session applied to the lower limb musculature (experimental group; n = 19) or no intervention (control group; n = 18). Balance stability and the automaticity of balance control were estimated through the calculation of the center-of-pressure (CoP) velocity (Vcop) and the statistical regularity (wavelet entropy) of the CoP trajectory (WEcop), respectively.

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The purpose of this review was to examine the literature on gaze behavior in referees. A literature search found only 12 relevant studies. Five of those studies were conducted on referees in association football (soccer), three on judges in gymnastics, one on softball umpires, and one each on referees in team handball, rugby, and ice hockey.

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The use of technology has been proposed to improve decision-making in sport officials. The implementation of the video Assistant Referee (VAR) in association football is one example of how technology can be used to assist decision making, although its impact remains unknown. In 2195 competitive football matches across 13 countries, the VAR conducted 9732 checks for potential match-changing incidents, with the median duration of a check being 22 seconds.

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In radiology, 60% to 80% of diagnostic errors are perceptual. The use of more efficient visual search behaviors is expected to reduce these errors. We collected eye-tracking data from participants with different levels of experience when interpreting chest X-rays during the completion of a pathology-detection task.

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The relative age effect (RAE) refers to the asymmetrical distribution of birthdates in a cohort found in many achievement domains, particularly in sports with many participants like soccer. Given the uniqueness of the one-child policy in China, this study examined the existence of the RAE in elite Chinese male and female soccer players generally and relative to their playing position on the field. Results showed a clear and obvious RAE for all age groups (U20 male, U18 male, adult female and U18 female) with the observed birthdate distributions for each age group significantly different from expected distributions (p<0.

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Perceptual-cognitive skills enable an individual to integrate environmental information with existing knowledge to be able to process stimuli and execute appropriate responses on complex tasks. Various underlying processes could explain how perceptual-cognitive skills impact on expert performance, as articulated in three theoretical accounts: (a) the long-term working memory theory, which argues that experts are able to encode and retrieve visual information from long-term working memory more than less experienced counterparts; (b) the information-reduction hypothesis, which suggests that experts can optimize the amount of information processed by selectively allocating their attentional resources to task relevant stimuli and ignore irrelevant stimuli; and (c) the holistic model of image perception, which proposes that experts are able to extract visual information from distal and para-foveal regions, allowing more efficient global-local processing of the scene. In this systematic review, we examine the validity of the aforementioned theories based on gaze features associated with the proposed processes.

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Inequalities in relative age distribution have previously been demonstrated to influence participation and performance achievements in Masters athletes. The purpose of the present study was to examine the participation- and performance-related constituent year effect among Masters athletes (N = 2,474) from the European Masters Track and Field Championships across subdisciplines and age. The results indicated that a participation-related constituent year effect was observed.

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Purpose: The influence of preceding load and future perceived wellness of professional soccer players is unexamined. This paper simultaneously evaluates the external load (EL) and internal load (IL) for different time frames in combination with presession wellness to predict future perceived wellness using machine learning techniques.

Methods: Training and match data were collected from a professional soccer team.

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The purpose of the current study was to examine the relationship between expertise, performance, and gaze behavior in a complex error-detection cockpit task. Twenty-four pilots and 26 non-pilots viewed video-clips from a pilot's viewpoint and were asked to detect malfunctions in the cockpit instrument panel. Compared to non-pilots, pilots detected more malfunctioning instruments, had shorter dwell times on the instruments, made more transitions, visited task-relevant areas more often, and dwelled longer on the areas between the instruments.

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In recent years, several publications examined the underlying mechanisms that might have an impact on decision-making processes under time pressure. This study investigated how individual differences in attentional capability relate to decision making in complex dynamic offside events. A total of 24 professional football assistant referees (ARs) performed an offside decision-making task and an attention-demanding task.

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There is an increasing trend in association football (soccer) to assist referees in their decision-making with video technology. For decisions such as whether a goal has been scored or which player actually committed a foul, video technology can provide more objective information and be valuable to increase decisional accuracy. It is unclear, however, to what extent video replays can aid referee decisions in the case of foul-play situations in which the decision is typically more ambiguous.

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