Affordance-based control in deceptive and non-deceptive penalties in soccer goalkeeping: Gender matters!

Only few studies have addressed how soccer goalkeepers adapt to both the spatial and temporal constraints while trying to stop a penalty kick. Moreover, research on penalty kicks has only involved male goalkeepers, even though the resultant constraint (i.e., the relation between the maximum action capabilities defining the time required and ball flight time and direction defining the time available) may or may not differ for female goalkeepers. We therefore compared penalty goalkeeping between male and female goalkeepers of similar skill level. The results showed that the resultant constraint was more stringent for female than male goalkeepers. In accordance with the affordance-based control theory, female and male goalkeepers both adapted to the resultant constraint, but did scale their diving action differently. Female goalkeepers initiated the lateral dive within the action boundaries set by the resultant constraint, while male goalkeepers tended to dive late, beyond the action boundaries. Owing to the early dive, female goalkeepers saved more penalties than male in non-deceptive penalties. Nevertheless, female goalkeepers were also more susceptible to deception by the penalty taker than male goalkeepers. These findings extend our knowledge of the affordance-based control theory in sports and contribute to the understanding of gender differences in soccer penalty goalkeeping.     

Availability of advance visual information constrains association-football goalkeeping performance during penalty kicks

A pressing concern within the literature on anticipatory perceptual-motor behaviour is the lack of clarity on the applicability of data, observed under video-simulation task constraints, to actual performance in which actions are coupled to perception, as captured during in-situ experimental conditions. We developed an in-situ experimental paradigm which manipulated the duration of anticipatory visual information from a penalty taker's actions to examine experienced goalkeepers' vulnerability to deception for the penalty kick in association football. Irrespective of the penalty taker's kick strategy, goalkeepers initiated movement responses earlier across consecutively earlier presentation points. Overall goalkeeping performance was better in non-deception trials than in deception conditions. In deception trials, the kinematic information presented up until the penalty taker initiated his/her kicking action had a negative effect on goalkeepers' performance. It is concluded that goalkeepers are likely to benefit from not anticipating a penalty taker's performance outcome based on information from the run-up, in preference to later information that emerges just before the initiation of the penalty taker's kicking action.     

Using perceptual home-training to improve anticipation skills of soccer goalkeepers

ObjectiveThis study aims to test the effectiveness of a perceptual training concerning the anticipatory skills of soccer goalkeepers, by assessing their performances while engaged in predicting the direction of penalty kicks.DesignForty-two skilled goalkeepers were randomly assigned to three training groups: Experimental, placebo, and control. All the groups were tested at the beginning of the experiment and re-tested after a period of eight weeks.MethodThe pre-test consisted of the presentation of temporally occluded videos of penalties recorded from the goalkeeper's perspective, and participants had to predict the direction of the ball. The experimental group practiced with an interactive home-training, based on video analogous to those of the test, with the addition of both positive and negative feedback. The placebo group viewed television footage of penalty kick shoot-outs. Participants of both groups were free to schedule their own training/placebo sessions. Finally, the control group did not receive any treatment.ResultsThe results demonstrated the effectiveness of the home-training protocol, evidencing significant accuracy improvements between pre-test and post-test only for the experimental group.ConclusionsThe outcomes indicate that skilled athletes can benefit from perceptual training, which was not investigated before among soccer goalkeepers. Indeed, all the previous training studies concerning soccer penalty predictions were run on participants with either recreational or no goalkeeping experience at all. Moreover, the present training protocol is innovative because learners can schedule training sessions on their own. Finally, its usability suggests numerous potential applications.     

The effect of fixation transitions on quiet eye duration and performance in the soccer penalty kick: instep versus inside kicks

Male goalkeepers of intermediate skill level attempted to stop penalty kicks executed with the instep and inside foot, in situ. A mobile eye tracker and an external camera were used to collect the gaze and motor behaviors of the goalkeepers, as well as the penalty takers’ motor behaviors and flight of the ball. Percent saves was greater during instep (28%) than inside foot kicks (12%), but we detected few differences in fixation frequency, location, duration, or transitions that could be attributed to the type of kick used. Fixation transitions (or the frequency of gaze shifts between locations) were significantly higher on goals than on saves. During the final phase of the kicking action, the quiet eye was located on the visual pivot and was longer during saves than goals. Furthermore, when the final fixation on the ball exceeded approximately 1,100 ms, then the likelihood of goals increased. The results are discussed in light of past studies in goaltending and the dual demands of motor tasks that require information be fixated both early and late at spatial locations that exceed the limits of focal vision.     

Psycho-perceptual-motor skills are deemed critical to save the penalty corner in international field hockey

In interceptive sports such as field hockey goalkeeping, the psycho-perceptual-motor skill anticipation is vital for performance due to the extreme time constraints associated with saving a goal. The purpose of this study was to understand the beliefs and attitudes of international field hockey goalkeepers and coaches regarding anticipation of the drag-flick in penalty corners. Seven international goalkeepers and five international coaches were interviewed. Using a constructionist and relativist approach to reflexive thematic data analysis, we identified three overarching themes to anticipate the drag-flick, namely, pre-match video analysis, perception and action, and psychological factors. In the first theme, participants reported that pre-match video analysis allowed goalkeepers and coaches to identify the attacking capabilities of opposing teams. This analysis was used to inform defensive structure and save the drag-flick. In the second theme, participants reported that perception and action, which consisted of the pick-up of visual cues and movement execution, was important to anticipate the drag-flick. Goalkeepers reported that they rely heavily on ball flight, which was central in coaches’ approaches in training drills such as to use a projection machine that presents only ball flight information. The third theme, psychological factors, encompassed, psychological resilience, arousal regulation, leadership and communication, and sports intelligence, which were thought to be vital to facilitate anticipation of the drag-flick. The findings of this study have important implications for how to assess and train visual anticipation in time-constrained interceptive sports skills.     

Tactical skills and ball speed during a field simulation of penalty kick strategies in soccer

This study investigates the efficacy of intermediate penalty kickers by comparing the effect of applying an automated WiFi system on the field of play to simulate a strategy that takes account of goalkeeper action (dependent) with another for which goalkeeper strategy is irrelevant (independent). Intermediate penalty kickers (n=12) took a pretreatment test of 32 kicks in a "real-play" situation with intermediate goalkeepers (n=3). Two groups of kickers underwent 11 treatment sessions using different strategies and then were administered a posttreatment test. The variables measured were the number of goals scored, whether the direction of the shot was the same or different from the direction of the goalkeeper's move (DDG), ball speed, and the duration of the kicking movement. Data suggested the goalkeepers had a greater capacity to identify advance cues when faced with independent strategy kickers and that dependent strategy kickers achieved lower ball speeds.     

The role of movement exaggeration in the anticipation of deceptive soccer penalty kicks

Human movement containing deception about the true outcome is thought to be perceived differently compared to the non‐deceptive version. Exaggeration in the movement is thought to change the perceiver's mode of functioning from an invariant to a cue‐based mode. We tested these ideas by examining anticipation in skilled and less skilled soccer players while they viewed temporally occluded (?240 ms, ?160 ms, ?80 ms, 0 ms, +80 ms) deceptive, non‐deceptive, and non‐deceptive‐exaggerated penalty kicks. Kinematic analyses were used to ascertain that the kicking actions differed across conditions. The accuracy of judging the direction of an opponent's kick as well as response confidence were recorded. Players were over confident when anticipating deceptive penalty kicks compared to non‐deceptive kicks, suggesting a cue‐based mode was used. Furthermore, there was a significant relationship between less skilled players’ confidence ratings and their accuracy 80 ms before ball‐foot contact in the deceptive and non‐deceptive‐exaggerated conditions, but not the non‐deceptive condition. Because both deceptive and non‐deceptive‐exaggerated kicks contained exaggeration, results suggest exaggerated movements in the kickers’ action at 80 ms before ball‐foot contact explains why a cue‐based mode prevails when anticipating deceptive kicks at this time point.     

Perceiving the inertial properties of actions in anticipation skill

Inertial properties of throwing or striking actions constrain action outcomes, but their role in anticipation skill has not been investigated yet. Therefore, the aim of this study was to systematically investigate the effect of inertial constraints on anticipation skill. Fifteen semi-professional and fifteen novice soccer players were tasked with determining the kick direction of penalty kicks occluded at 160 ms, 80 ms before ball-foot contact, at ball-foot contact, or 80 ms after ball-foot contact. The inertial constraints were manipulated by loading the kicking leg with a 2.25 kg weight around the shank of the kicking leg and were compared with unloaded kicks. Anticipation accuracy of kick direction, response time, and decision confidence were recorded. It was found that loaded kick directions were anticipated more accurately, faster, and at earlier occlusion periods than unloaded kicks. The higher accuracy for the loaded kicks was found in the earlier occlusion conditions in experts compared to novices, as were the positive relationships between accuracy and confidence. It was concluded that the perception of the inertial constraints of the kicking action allowed for earlier anticipation of kick direction. It is proposed that accurate perception of the biomechanical property radius of gyrations in the body segments linking proximal to distal towards the kicking foot may provide this information.     

Examination of gaze behaviors under in situ and video simulation task constraints reveals differences in information pickup for perception and action

Queensland University of Technology, Brisbane, Queensland, Australia Gaze and movement behaviors of association football goalkeepers were compared under two video simulation conditions (i.e., verbal and joystick movement responses) and three in situ conditions (i.e., verbal, simplified body movement, and interceptive response). The results showed that the goalkeepers spent more time fixating on information from the penalty kick taker’s movements than ball location for all perceptual judgment conditions involving limited movement (i.e., verbal responses, joystick movement, and simplified body movement). In contrast, an equivalent amount of time was spent fixating on the penalty taker’s relative motions and the ball location for the in situ interception condition, which required the goalkeepers to attempt to make penalty saves. The data suggest that gaze and movement behaviors function differently, depending on the experimental task constraints selected for empirical investigations. These findings highlight the need for research on perceptual— motor behaviors to be conducted in representative experimental conditions to allow appropriate generalization of conclusions to performance environments.     

Effect of verbal cueing on trajectory anticipation in the penalty kick among novice football goalkeepers

The effect of a cueing technique on novice goalkeepers' anticipation of trajectory in penalty kicks was investigated. 28 novice football goalkeepers from junior teams were randomly selected and divided into experimental (n = 14) and control (n = 14) groups. Following a pre-test, participants performed 30 trials of a simulated penalty-kicking task in a spatially occluded condition. They were required to react to penalty kicks and were informed of their performance in anticipating the direction in which the ball was kicked. The experimental group received cues about the position of the non-kicking foot of the kicker, but the control group did not. The two-way analysis of variance showed the significant main effects of blocks of trials and group, but the interaction was not significant. The experimental group more accurately anticipated the direction of the penalty kicks than the control group. The cueing technique benefited the novice goalkeepers in anticipating the direction of penalty kicks, due to the informative nature of the cue for skill execution.     

The power of nonverbal behavior: Penalty-takers’ body language influences impression formation and anticipation performance in goalkeepers in a simulated soccer penalty task

Previous research showed that penalty-takers’ body language affects the impressions goalkeepers form about them. Furthermore, it is often assumed that body language influences goalkeepers’ performance. However, as yet, there is no empirical evidence that indicates whether this latter effect exists. The present research was aimed at (1) replicating and offering more insight in the initial impression formation effects (Experiment 1-3) and (2) providing evidence that signals of dominance and submissiveness affect participants’ anticipation performance within a simulated soccer penalty task (Experiment 3). We report three experiments demonstrating that participants form more positive impressions and have less confidence in saving penalty kicks from dominant penalty-takers (or scoring against dominant goalkeepers, Experiment 1) than submissive penalty-takers (goalkeepers). However, we did not find evidence that participants’ automatic associations with dominant and submissive players underlie these findings (Experiment 2). Finally, we demonstrate that anticipation of kick direction is influenced by penalty-takers’ body language (Experiment 3). Participants performed worse in the simulated soccer penalty task against dominant than submissive penalty-takers. No mediation of impression formation was found.     

The effectiveness of penalty takers' deception: A scoping review

Attackers are supposed to take advantage of producing deceptive actions in competitive ball sports, particularly in penalty situations. We conducted a scoping review of the experimental literature to scrutinize whether penalty takers do indeed benefit from using deceptive actions in penalty situations, especially by increasing the likelihood to score a goal. Studies using video-based and in-situ tasks in which soccer and handball goalkeepers try to save a penalty were evaluated. Results showed that penalty takers' manipulation of spatial information available to the goalkeeper during deception (i.e., by using misleading and/or disguising actions) is less effective in in-situ than video-based studies. We argue that this difference occurs because goalkeepers adapt differently to the spatiotemporal constraints in the video-based and in-situ tasks. Goalkeepers appear to prioritize picking up spatial information in video-based tasks while prioritizing temporal information in-situ tasks. Therefore, the manipulation of spatial information appears to be less effective in the more representative in-situ studies than in video-based studies. In order to deceive, penalty takers are advised to manipulate temporal information during on-field penalty situations.     

Statistical modelling of gaze behaviour as categorical time series: what you should watch to save soccer penalties

Previous research on gaze behaviour in sport has typically reported summary fixation statistics thereby largely ignoring the temporal sequencing of gaze. In the present study on penalty kicking in soccer, our aim was to apply a Markov chain modelling method to eye movement data obtained from goalkeepers. Building on the discrete analysis of gaze employed by Dicks et al. (Atten Percept Psychophys 72(3):706–720, 2010b), we wanted to statistically model the relative probabilities of the goalkeeper’s gaze being directed to different locations throughout the penalty taker’s approach (Dicks et al. in Atten Percept Psychophys 72(3):706–720, 2010b). Examination of gaze behaviours under in situ and video-simulation task constraints reveals differences in information pickup for perception and action (Attention, Perception and Psychophysics 72(3), 706–720). The probabilities of fixating anatomical locations of the penalty taker were high under simulated movement response conditions. In contrast, when actually required to intercept kicks, the goalkeepers initially favoured watching the penalty taker’s head but then rapidly shifted focus directly to the ball for approximately the final second prior to foot-ball contact. The increased spatio-temporal demands of in situ interceptive actions over laboratory-based simulated actions lead to different visual search strategies being used. When eye movement data are modelled as time series, it is possible to discern subtle but important behavioural characteristics that are less apparent with discrete summary statistics alone.     

Anticipation from biological motion: the goalkeeper problem

People can often anticipate the outcome of another person's actions based on visual information available in the movements of the other person's body. We investigated this problem by studying how goalkeepers anticipate the direction of a penalty kick in soccer. The specific aim was to determine whether the information used to anticipate kick direction is best characterized as local to a particular body segment or distributed across multiple segments. In Experiment 1, we recorded the movements of soccer players as they kicked balls into a net. Using a novel method for analyzing motion capture data, we identified sources of local and distributed information that were reliable indicators of kick direction. In Experiments 2 and 3, subjects were presented with animations of kickers' movements prior to foot-to-ball contact and instructed to judge kick direction. Judgments were consistent with the use of distributed information, with a possible small contribution of local information.     

“Get it out the way. The wait's killing me.” hastening and hiding during soccer penalty kicks

ObjectivesIt has been suggested that hastening and hiding—rushing through penalty preparation and not looking at the goal when preparing the penalty kick—are associated with negative penalty taking performance. In the present study, we investigated how opposing players perceived these nonverbal behaviors, how they affect outcome expectations, and how they affect the behavior of opposing goalkeepers.DesignThe present study employs an experimental research design (Experiment 1: 2 (gaze behavior) × 3 (preparation time) design; Experiment 2: 2 (gaze behavior) × 2 (preparation time) design).MethodWe examined the perception of nonverbal hastening and hiding behavior using the point-light technique during the soccer penalty kick among goalkeepers (Experiment 1a; n = 20), and among outfield soccer players (Experiment 1b; n = 29). Furthermore, we analyzed how these respective penalty preparation strategies influenced the behavior of high-level goalkeepers (n = 12) under in situ conditions (Experiment 2).ResultsThe results from Experiment 1 demonstrated that penalty takers showing hastening and hiding behaviors are perceived more negatively by both soccer goalkeepers and outfield players: (i) they are considered to possess less positive attributes, (ii) to have less accuracy in their penalties, and (iii) likely to perform less well in penalty situations. Experiment 2 provided first evidence that goalkeepers initiate their movement later following the observation of hastening and hiding behaviors during the penalty preparation.ConclusionsOur findings demonstrate the importance of investigating nonverbal behavior in sports as these have a major impact on impression formation, expected performance, and actual behavior of opposing players in the soccer penalty situation.     

Effects of providing advance cues during a soccer penalty kick on the kicker's rate of success

The effect of explicitly providing goalkeeper's movement advanced cue to the kicker during a real penalty kick task was assessed. 32 expert soccer players (M age= 23.2 yr.), who were divided into four groups: an experimental group, a discovery group, a placebo group, and a control group, participated. Rate of success in the task was assessed, as well as goals, decision times, and ball flight times. Providing an advance cue significantly improved the players' rate of success relative to players without the advance cue; this difference was still present after 1 and 7 days without training. The experimental group adapted better to the time range within which the response could be effective, while the discovery group showed adaptations. Explicit instructions about the advance cues available from goalkeepers' actions before the dive during practice can improve penalty kick performance.     

Individual differences in performance and learning of visual anticipation in expert field hockey goalkeepers

The study of anticipation in truly expert performers can provide insight into how they cope with extreme time constraints. The purpose of this dual-experiment paper was to investigate individual differences; in anticipation of the penalty corner drag-flick, its trainability, and transfer of improvement to field settings. Australian international and national male field-hockey goalkeepers participated. In experiment 1, international and national goalkeepers (n = 11) completed a penalty corner drag-flick temporal occlusion task that presented; defensive runner positioning at the penalty spot, drag-flicker kinematics, and ball flight. Results indicated seven goalkeepers integrated runner contextual and drag-flicker kinematic information to anticipate above chance. The cause of individual differences was independent pick-up of run and kinematic cues that presented greater opportunity to integrate sources for anticipation. In experiment 2, a sub-sample of goalkeepers participated and received temporal occlusion training or no training. Results indicated individualized improvement in anticipation across video, field, and competition assessments for those that received the intervention, but not controls. Improvements on video test were retained for six months. An individual differences approach can identify deficiencies in anticipation, which can be improved through perceptual training that transfers to motor responses. This contributes to theoretical and practical knowledge to develop anticipation skill.     

Examining Action Effects in the Execution of a Skilled Soccer Kick by Using Erroneous Feedback

The authors examined the role of action effects (i.e., ball trajectory) during the performance of a soccer kick. Participants were 20 expert players who kicked a ball over a height barrier toward a ground-level target. The authors occluded participants' vision of the ball trajectory after foot-to-ball contact. Participants in a 1st group received erroneous feedback from a video that showed a ball-trajectory apex approximately 75 cm lower than that of their actual kick, although the ball's landing position was unaltered. Participants in a 2nd group received correct video feedback of both the ball trajectory and the landing position. The erroneous-feedback group showed a significant bias toward higher ball trajectories than did the correct-feedback group. The authors conclude that performers at high levels of skill use the visual consequences of the action to plan and execute an action.     

Predicting the lateral direction of deceptive and non-deceptive penalty kicks in football from the kinematics of the kicker

This study addresses the utility of the kinematics of penalty takers for goalkeepers in association football. Twelve professional and semi-professional players shot to one side of the goal with (deceptive condition) or without (non-deceptive condition) simulating a shot to the opposite side. The body kinematics of the penalty takers were registered with motion-capture apparatus. Correlation and regression techniques were used to determine the relation between the shot direction and aspects of the penalty taker’s kinematics at different moments. Several kinematic variables were strongly correlated with shot direction, especially those related to the lower part of the body. Some of these variables, including the angle of the non-kicking foot, acquired high correlations at time intervals that are useful to goalkeepers. Compound variables, here defined as linear combinations of variables, were found to be more useful than locally defined variables. Whereas some kinematic variables showed substantial differences in their relation to ball direction depending on deception, other kinematic variables were less affected by deception. Results are interpreted with the hypothesis of non-substitutability of genuine action. The study can also be interpreted as extending the correlation and regression methodology, often used to analyze variables defined at single moments, to the analysis of variables in a time continuous fashion.     

Adaptive Dynamics of the Leg Movement Patterns of Human Infants: III. Age-Related Differences in Limb Control

In this article, the development of the increasingly differentiated control of the joints necessary to transform the spontaneous leg movements of early infancy into adaptive and functional actions is described. The hypothesis-that increasing joint control requires the capability for disassociation of joint action, the active modulation of joint stiffness, and a transition from proximal to distal control of the joints-is proposed. Kinematic and kinetic analyses of the vertical kicks of infants 2 weeks, 3 months, and 7 months of age (as well as a comparative group of adults) indicated increasing joint independence as well as phase-dependent and joint-dependent control modifications. The kicks of the younger infants were dominated by a proximal control strategy and minimal adjustments of the limb energetics during the flexion and extension phases of the kick. By 7 months of age, much larger modulations of the kick phases were observed as well as increasing evidence of distal control. These results revealed kinematic and kinetic patterns of emerging limb control between 2 weeks and 7 months of age.