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The One-Target Advantage: Advanced Preparation or Online Processing?

Ann Lavrysen, Werner F. Helsen, Digby Elliott, and Jos J. Adam

The one-target advantage refers to a shorter movement time for one-target aiming movements, in comparison to aiming attempts followed by a second movement. Theoretical explanations of the one-target advantage vary in the extent to which they attribute this phenomenon to prior planning or to online control mechanisms. In this research, we attempted to gain insight into the control of sequential aiming movements by manipulating the availability of online feedback during this first or second movement component. When the participants' vision was occluded during the first movement (Experiment 1) or during the second movement (Experiment 2), their performance was affected, showing that vision was important for online control of the movement sequence. A one-target advantage was found when the second movement was in the same direction as me first, but not when it was reversed with respect to the home button. Both prior planning and online control processes contribute to the one-target advantage. The degree to which these processes are important for limb control depends on the specific task demands.

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Team Sports and the Theory of Deliberate Practice

Werner F. Helsen, Janet L. Starkes, and Nicola J. Hodges

Two studies tested the theory of deliberate practice (Ericsson, Krampe, & Tesch-Romer, 1993) and contrasted results with the sport commitment model (Scanlan, Carpenter, Schmidt, Simons, & Keeler, 1993a, 1993b). In Part I, international, national, and provincial soccer and field hockey players recalled the amount of time they spent in individual and team practice, sport-related activities, and everyday activities at the start of their career and every 3 years since. In Part II, these activities were rated in terms of their relevance for improving performance, effort and concentration required, and enjoyment. A monotonic relationship between accumulated individual plus team practice and skill level was found. In contrast with Ericsson et al.’s (1993) findings for musicians, relevant activities were also enjoyable, while concentration became a separate dimension from effort. The viability of a generalized theory of expertise is discussed.

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Does Visual Attention Impact on Decision Making in Complex Dynamic Events?

Stefanie Hüttermann, Werner F. Helsen, Koen Put, and Daniel Memmert

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. ARs with higher attentional capability along the horizontal meridian of their attentional focus made fewer mistakes when judging offside situations in football than ARs with lower capability. This implies that being able to rely on high-attentional capabilities in situations requiring conscious perception of multiple processes is likely to be beneficial for the ultimate decision-making performance.

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Effects of Target Eccentricity on Temporal Costs of Point of Gaze and the Hand in Aiming

Werner F. Helsen, Janet L. Starkes, and Martinus J. Buekers

This experiment addresses the coordination of point of gaze (PG) and hand movements in a speeded aiming task to predictable targets of three different eccentricities (35, 40, and 45 cm). In each condition subjects moved the eyes, head, trunk, and hand freely. Performance was assessed on 5 blocks of 5 trials. Analyses were conducted for (a) frequencies for initiation order of PG and the hand, (b) correlation between initiation latencies of PG and the hand, and (c) initiation, movement, and response times of PG and the hand. PG always arrived on target in advance of the hand and at approximately 50% of the response time of the hand (proportional time).Varying eccentricity increased initiation time of PG but not of the hand. With learning there was an initial temporal improvement and decreased variability of response within the first 10 trials, and with additional practice response times were further reduced. The importance of proportional time and its relationship to the first submovement in aiming are discussed.

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Methodological Considerations When Quantifying High-Intensity Efforts in Team Sport Using Global Positioning System Technology

Matthew C. Varley, Arne Jaspers, Werner F. Helsen, and James J. Malone


Sprints and accelerations are popular performance indicators in applied sport. The methods used to define these efforts using athlete-tracking technology could affect the number of efforts reported. This study aimed to determine the influence of different techniques and settings for detecting high-intensity efforts using global positioning system (GPS) data.


Velocity and acceleration data from a professional soccer match were recorded via 10-Hz GPS. Velocity data were filtered using either a median or an exponential filter. Acceleration data were derived from velocity data over a 0.2-s time interval (with and without an exponential filter applied) and a 0.3-second time interval. High-speed-running (≥4.17 m/s2), sprint (≥7.00 m/s2), and acceleration (≥2.78 m/s2) efforts were then identified using minimum-effort durations (0.1–0.9 s) to assess differences in the total number of efforts reported.


Different velocity-filtering methods resulted in small to moderate differences (effect size [ES] 0.28–1.09) in the number of high-speed-running and sprint efforts detected when minimum duration was <0.5 s and small to very large differences (ES –5.69 to 0.26) in the number of accelerations when minimum duration was <0.7 s. There was an exponential decline in the number of all efforts as minimum duration increased, regardless of filtering method, with the largest declines in acceleration efforts.


Filtering techniques and minimum durations substantially affect the number of high-speed-running, sprint, and acceleration efforts detected with GPS. Changes to how high-intensity efforts are defined affect reported data. Therefore, consistency in data processing is advised.

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The Impact of Age and Physical Activity Level on Manual Aiming Performance

Florian Van Halewyck, Ann Lavrysen, Oron Levin, Digby Elliott, and Werner F. Helsen

Older adults traditionally adapt their discrete aiming movements, thereby traveling a larger proportion of the movement under closed-loop control. As the beneficial impact of a physically active lifestyle in older age has been described for several aspects of motor control, we compared the aiming performance of young controls to active and sedentary older adults. To additionally determine the contribution of visual feedback, aiming movements were executed with and without saccades. Results showed only sedentary older adults adopted the typical movement changes, highlighting the impact of a physically active lifestyle on manual aiming in older age. In an attempt to reveal the mechanism underlying the movement changes, evidence for an age-related decline in force control was found, which in turn resulted in an adapted aiming strategy. Finally, prohibiting saccades did not affect older adults’ performance to a greater extent, suggesting they do not rely more on visual feedback than young controls.

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The Constituent Year Effect in European Track and Field Masters Athletes: Evidence of Participation and Performance Advantages

Werner F. Helsen, Nikola Medic, Janet L. Starkes, and Andrew M. Williams

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. The likelihood of participation was significantly higher for athletes in their first year of any 5-year age category (χ2 = 149.8, p < .001) and decreased significantly when they were in the fourth or fifth year. The results also indicated a performance-related constituent year effect. Masters athletes in their first year won significantly more medals than expected based on observed participation rate (χ2 = 23.39, p < .001). We compare our results with the existing literature and discuss potential mechanisms for this constituent year effect.

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Experts in Offside Decision Making Learn to Compensate for Their Illusory Perceptions

Koen Put, Marcus V.C. Baldo, André M. Cravo, Johan Wagemans, and Werner F. Helsen

In association football, the flash-lag effect appears to be a viable explanation for erroneous offside decision making. Due to this spatiotemporal illusion, assistant referees (ARs) perceive the player who receives the ball ahead of his real position. In this experiment, a laboratory decision-making task was used to demonstrate that international top-class ARs, compared with amateur soccer players, do not have superior perceptual sensitivity. They clearly modify their decision criterion according to the contextual needs and, therefore, show a higher response bias toward not responding to the stimulus, in particular in the most difficult situations. Thus, international ARs show evidence for response-level compensation, resulting in a specific cost (i.e., more misses), which clearly reflects the use of particular (cognitive) strategies. In summary, it appears that experts in offside decision making can be distinguished from novices more on the cognitive or decision-making level than on the perceptual level.

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Differential Ratings of Perceived Exertion: Relationships With External Intensity and Load in Elite Men’s Football

Kobe C. Houtmeyers, Pieter Robberechts, Arne Jaspers, Shaun J. McLaren, Michel S. Brink, Jos Vanrenterghem, Jesse J. Davis, and Werner F. Helsen

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. After each session, players rated their perceived breathlessness and leg-muscle exertion. Descriptive statistics were calculated to quantify how often players rated the 2 types of rating of perceived exertion differently (dRPEDIFF). In addition, the association between dRPEDIFF and external intensity and load was examined. First, the associations between single external variables and dRPEDIFF were analyzed using a mixed-effects logistic regression model. Second, the link between dRPEDIFF and session types with distinctive external profiles was examined using the Pearson chi-square test of independence. Results: On average, players rated their session perceived breathlessness and leg-muscle exertion differently in 22% of the sessions (range: 0%–64%). Confidence limits for the effect of single external variables on dRPEDIFF spanned across largely positive and negative values for all variables, indicating no conclusive findings. The analysis based on session type indicated that players differentiated more often in matches and intense training sessions, but there was no pattern in the direction of differentiation. Conclusions: The findings of this study provide no evidence supporting the utility of dRPE for monitoring internal intensity and load in football.

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Monitoring Elite Youth Football Players’ Physiological State Using a Small-Sided Game: Associations With a Submaximal Running Test

Kobe C. Houtmeyers, Werner F. Helsen, Arne Jaspers, Sjaantje Nanne, Shaun McLaren, Jos Vanrenterghem, and Michel S. Brink

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). HRex was collected during both protocols, with SSG external load measured as high-speed running distance (>19.8 km·h–1) and acceleration distance (>2 m·s−2). Data were analyzed using linear mixed-effect models. Results: Controlling for SSG external load improved the model fit describing the SSG–ISRT HRex relationship (χ 2 = 12.6, P = .002). When SSG high-speed running distance and SSG acceleration distance were held constant, a 1% point change in SSG HRex was associated with a 0.5% point change in ISRT HRex (90% CI: 0.4 to 0.6). Inversely, when SSG HRex was held constant, the effects of a 100-m change in SSG high-speed running distance and a 21-m change in SSG acceleration distance on ISRT HRex were −1.0% (−1.5 to −0.4) and −0.6% points (−1.1 to 0.0), respectively. Conclusions: An SSG can be used to track within-player changes in HRex for monitoring physiological state. Given the uncertainty in estimates, we advise to only give meaning to changes in SSG HRex >2% points. Additionally, we highlight the importance of considering external load when monitoring SSG HRex.