Soccer Kick Research Articles

Effects of Soccer Kicking Training Using Virtual Reality on Kicking Performance in Boy Soccer Players

PURPOSE: Adoption of virtual reality (VR) into sports, games, and educational settings has become popular in recent years, but no evidence regarding VR’s effects on athlete’s performance has been elucidated. This study evaluated an efficacy of VR soccer kicking training system for kicking performance in young soccer players. METHODS: A total of 24 experienced boy soccer players enrolling in a elementary school soccer team was recruited for the 6 months study, and divided into two groups; VR training group (VR-G; n=13, 11.8±1.0 yrs, 148±7.5 cm, 39.0±7.9 kg) and outdoor training group (OT-G; n=11, 11.4±3.4 yrs, 152±9.7 cm, 45.2±10.2 kg). Before (M0) and after (M6) the study, they were tested. For the test, they kicked a ball, in which a sensor was installed, to a curtain screen on which targets were marked by a beam. The VR room was sized 12×8 meter. Using the data of ball speed and target hitting accuracy, a scoring point was calculated for kicking accuracy (Ka) and speed (Ks). They were also tested on a soccer field for measurement of kicking accuracy (Kfa). For the test, they practiced twice and kicked 5 times for measurement. During the study, they were trained for two phases; regular and extra training. For the regular training, the team was trained 4 times/week in a soccer field for 120 min/session. For a total of 15 sessions of extra training, OT-G practiced only kicking on the field, while VR-G did in a VR room. RESULTS: For VR-G, Ka, Ks, and Kfa increased from 53.6±9.5, 26.1±11.8, and 18.6±14.9 at M0 to 62.9±10.0 (t=-6.138, p<.001), 38.0±13.2 (t=-2.396, p<0.05), and 31.9±16.0 unit (t=-2.442, p<0.05), respectively. For OT-G, Ka, Ks, and Kfa were not changed from 58.8±8.9, 35.9±15.5, and 19.6±13.6 at M0 to 63.1±5.7, 29.1±10.0, 22.2±12.8 unit, respectively. No differences were found in 3 kicking variables at M0 and M6 between two groups. CONCLUSION: The regular soccer training and the extra kicking training improved the kicking speed and accuracy in VR-G, while OT-G maintained their performance. VR soccer kicking training program could be a potential substitutional and additional training model for young soccer players. (This research project was supported by the Spors Promotion Fund of Seoul Olympic Sports Promotion Foundation from Ministry of Culture, Sports and Tourism, project # s072016122016)

VR 스포츠실을 활용한 훈련 프로그램이 초등학교 축구선수 킥의 수행에 미치는 영향

VR 스포츠실을 활용한 훈련 프로그램이 초등학교 축구선수 킥의 수행에 미치는 영향

The ball kicking speed: A new, efficient performance indicator in youth soccer.

Success in different soccer skills like kicking depends on motor abilities achieved. Kicking is a soccer fundamental, which depends on many different and complex factors (technique, foot-ball interaction, ball flight, etc.). Therefore, it is important to identify players that are able to perform faster kicks using both dominant and non-dominant leg. The current study investigated some basic variables of different soccer kicking speed and their relevance to success in youth soccer academy. 119 players from the first and the second division participated to this study. They were randomly divided into age groups (U-15, U-17, and U19) and team status (first team, reserves). The diagnostic ability of the different ball kicking speed tests in capturing differences between first team players and reserves among different age categories were computed using the receiver operating characteristics analysis. Results demonstrated that first team players achieved better results when comparing to reserves in each category. In addition, differences were greater in the U-15 and the U-17 than in the U-19 age group. In conclusion, ball kicking speed could be one of the possible identification tools to evaluate players' success in youth soccer.

THIGH MUSCLES ACTIVATION DURING SOCCER INSTEP KICK

The aim of the study was to compare Quadriceps group of muscles and Hamstring group of muscles during soccer Instep kick. Methodology: The investigator had selected Eight male soccer players of inter University/national level were selected as subjects for the study. Hence, purposive sampling was considered for selection of subjects. The age of subjects ranged from 18-25 years. All the subjects were selected from Banaras District. These players had represented inter University/national level and had no lower extremity injuries or any bone joint disparities in the past years. By reviewing the literature and in consultation with the expert, the research scholar carried out an intensive study and selected major muscles such as Rectus femories, Vastus lateralis and Vastus medialis from quadriceps group and Biceps femoris, Semimembranous and Semitendinous from hamstring group of muscles. The criterion measure adopted for this study was measured by Neuro track Myoplus 2/4 channel. After a brief warm-up, and electrode placement, participants performed the instep kick. Descriptive statistics and One way Analysis of Variance (ANOVA) was used to analyze the data. Results: Results of this study have shown that, mean value of Vastus Lateralis muscles have the highest activation with Mean (196.8) and insignificant difference found among the selected muscles i.e. Vastus Lateralis, Rectus femoris, Semimembranous, Biceps femoris, Vastus Medialis and Semitendinous during instep kick from penalty spot in soccer. Where calculated F (0.706) is less than Tabulated F (2.44). Conclusion: On the basis of result and finding it may be concluded that while Instep kicking in football Vastus Lateralis shows the highest activation. Comparison between all selected muscles contraction in lower limb of thigh muscles were found insignificant during the instep kick in soccer, this insignificant was found because the functioning of all the selected muscles are working together in reciprocal way. Article visualizations:

A Study of Center of Gravity in Different Phases of Selected Soccer Kicks

The center of gravity (CG) of the human body is a hypothetical point around which the force of gravity appears to act. CG need not lie within the physical bounds of an object. Human beings do not remain fixed in the anatomical position and the precise location of the CG changes constantly with every new position of the body and limbs. CG plays an important role in maintaining balance, equilibrium, and breaking inertia during the performance of a sports technique. Purpose of this study is to discover the pattern and make the comparison of CG height and CG velocity changes in the execution of frequently used soccer kicks within and between the kicks by the male players. Five male players played for the Bangladesh National Football teams were selected as subject and their age was between 16-19 years. A Cannon EOS7D with the capacity of 55 f/sec camera placed on sagittal plane at the backside of the kick 5.00 meters away and at 1.13 meter of height to capture kicking actions of the players on Coronal/Frontal plane. The best frame was selected out of 3 trials. 2D motion Analysis Software Kinovea 0.8.25 was employed for the quantitative analysis of the video clips. Changing of the CG height position in percentage was studied in three different phases i.e. Ground contact, Ball contact, and Follow-through in reference to erect standing CG height of the players. In addition, CG velocity changes were also studied in ball contact and follow-through phases. This study demonstrates that the male soccer players demonstrate inconsistency in CG height reduction in performing all three phases (Ground Contact, Ball Contact, & Follow-through) in all selected five kicks (Push Pass, Instep Kick, Lofted Kick, Chip Shot, and In-swerve Kick), but highest reductions have been located in the ball contact phase of all the kicks. Players change CG height in the same manner among the five selected kicks in each of the phases distinctly. Players experience CG height drop in Instep Kick differently between ball contact and ground contact phases. Players display higher mean CG velocity in ball contact phase than follow-through phase in Push Pass but remaining other kicks exhibit opposite actions. Players display CG velocity in all selected soccer kicks in the same manner at ball contact and follow-through phases. Players change CG velocity differently between Push Pass and Instep Kick, In-swerve Kick, Lofted Kick at follow-through phase.

Simple quantification of foot speed generating mechanism of soccer kicking using IMUs

Simple quantification of foot speed generating mechanism of soccer kicking using IMUs

The effects of midsole bending stiffness on ball speed during maximum effort soccer kicks

The soccer kick is the most prominent movement in soccer. Kicking performance depends on two major factors: kicking accuracy and ball speed. During the soccer kick, momentum is transferred from the foot/cleat to the ball. This interplay between the foot/cleat and the ball can be modelled as a mixture of ‘impulse-like’ and ‘throwing-like’ components. While kicking the ball, the metatarsophalangeal (MTP) joint and the cleat experience deformation. This deformation can be reduced by increasing the bending stiffness of the cleat’s midsole. Therefore, the purpose of this study was to investigate experimentally the influence of midsole bending stiffness on ball speed during maximum effort soccer kicks. Twenty male subjects (mean ± SD; age: 29.5 ± 5.6 years, height: 175.5 ± 6.4 cm, mass: 74.3 ± 8.4 kg) performed six maximum effort soccer kicks in five stiffness conditions. Kinematic data were collected using an optical motion capture system consisting of eight high-speed cameras, and ball speed was recorded using a radar gun. There was no significant difference in the average ball speed between the five stiffness conditions when all subjects were pooled. Further, there was no significant difference in the change of the MTP joint angle from before ball contact to after ball contact between the stiffness configurations. Thirteen (of the 20) subjects showed the highest ball speed in the two stiffest cleats. The differences between the best and the worst performing stiffness configurations across all subjects ranged from 2.2 km/h to 9.2 km/h. The optimal stiffness condition that resulted in highest ball speed was subject specific, and therefore soccer cleats need to be tuned to individual players.

Biomechanics of coaching maximal instep soccer kick for practitioners

ABSTRACTKicking in soccer has been the subject of scientific research for more than 40 years yet review articles summarizing the biomechanical fundamentals of kick optimization as a guide to coaching are scarcely to be found. The current review article aims to bridge the gap between scientific research into the maximal instep kick (including studies employing 3D motion capture and full-body biomechanical modelling) and the application of such research in coaching. It does so by supplying a scientifically founded, coaching-friendly article explaining identifiable characteristics and motor control sequencing that define this skill. Relevant biomechanical factors are identified in a way that should help coaches better develop training programmes and, at the same time, foster better understanding of the skill among athletes. Such information will contribute to both accelerated skill acquisition and, by concomitant gains in skill efficiency, the development of programmes that minimize risk of injury to athletes during training.

Electromyographic analysis of hip adductor muscles in soccer instep and side-foot kicking

ABSTRACTA possible link between soccer-specific injuries, such as groin pain and the action of hip adductor muscles has been suggested. This study aimed to investigate neuromuscular activation of the adductor magnus (AM) and longus (AL) muscles during instep and side-foot soccer kicks. Eight university soccer players performed the two types of kick at 50%, 75% and 100% of the maximal ball speed. Surface electromyography (EMG) was recorded from the AM, AL, vastus lateralis (VL) and biceps femoris (BF) muscles of both kicking and supporting legs and the kicking motions were three-dimensionally captured. In the kicking leg, an increase in surface EMG with an increase in ball speed during instep kicking was noted in the AM muscle (p < 0.016), but not in AL, VL or BF muscles (p > 0.016). In the supporting leg, surface EMG of both AM and AL muscles was significantly increased with an increase in the ball speed before ball impact during both instep and side-foot kicks (p < 0.016). These results suggest that hip adductor muscles markedly contribute to either the kicking or supporting leg to emphasise the action of soccer kicks.

Intermittent Treadmill Running Induces Kinematic Compensations to Maintain Soccer Kick Foot Speed Despite No Change in Knee Extensor Strength.

Kicking is a fundamental skill and a primary noncontact mechanism of injury in soccer, with injury incidence increasing during the latter stages of match-play. Ten male professional soccer players completed a 90-minute treadmill protocol based on the velocity profile of soccer match-play. Preexercise, and at 15-minute intervals, players completed a maximal velocity kick subjected to kinematic analysis at 200Hz. Preexercise, and at the end of each half, players also completed isokinetic concentric knee extensor repetitions at 180°·s-1, 300°·s-1, and 60°·s-1. Kicking foot speed was maintained at ∼19m·s-1, with no main effect for exercise duration. In relation to proximal-distal sequencing during the kicking action, there was a significant increase in the duration (but not magnitude) of thigh rotation, with a compensatory decrease in the duration (but not magnitude) of shank rotation during the latter stages of the exercise protocol. In relation to long-axis rotation, pelvic orientation at ball contact was maintained at ∼6°, representing a total pelvic rotation in the order of ∼15° during the kicking action. Peak knee extensor torque at all speeds was also maintained throughout the protocol, such that kinematic modifications are not attributable to a decline in knee extensor strength.

On-Line Detection and Segmentation of Sports Motions Using a Wearable Sensor.

In sports motion analysis, observation is a prerequisite for understanding the quality of motions. This paper introduces a novel approach to detect and segment sports motions using a wearable sensor for supporting systematic observation. The main goal is, for convenient analysis, to automatically provide motion data, which are temporally classified according to the phase definition. For explicit segmentation, a motion model is defined as a sequence of sub-motions with boundary states. A sequence classifier based on deep neural networks is designed to detect sports motions from continuous sensor inputs. The evaluation on two types of motions (soccer kicking and two-handed ball throwing) verifies that the proposed method is successful for the accurate detection and segmentation of sports motions. By developing a sports motion analysis system using the motion model and the sequence classifier, we show that the proposed method is useful for observation of sports motions by automatically providing relevant motion data for analysis.

Modeling the two-dimensional accuracy of soccer kicks

In many sports, athletes perform motor tasks that simultaneously require both speed and accuracy for success, such as kicking a ball. Because of the biomechanical trade-off between speed and accuracy, athletes must balance these competing demands. Modelling the optimal compromise between speed and accuracy requires one to quantifyhow task speed affects the dispersion around a target, a level of experimental detail not previously addressed. Using soccer penalties as a system, we measured two-dimensional kicking error over a range of speeds, target heights, and kicking techniques. Twenty experienced soccer players executed a total of 8466 kicks at two targets (high and low). Players kicked with the side of their foot or the instep at ball speeds ranging from 40% to 100% of their maximum. The inaccuracy of kicks was measured in horizontal and vertical dimensions. For both horizontal and vertical inaccuracy, variance increased as a power function of speed, whose parameter values depended on the combination of kicking technique and target height. Kicking precision was greater when aiming at a low target compared to a high target. Side-foot kicks were more accurate than instep kicks. The centre of the dispersion of shots shifted as a function of speed. An analysis of the covariance between horizontal and vertical error revealed right-footed kickers tended to miss below and to the left of the target or above and to the right, while left-footed kickers tended along the reflected axis. Our analysis provides relationships needed to model the optimal strategy for penalty kickers.

Kicking Performance in Young U9 to U20 Soccer Players: Assessment of Velocity and Accuracy Simultaneously

ABSTRACTPurpose: The purpose of this study was to compare the kicking performance of young soccer players in the U9 to U20 age groups. Method: Three hundred and sixty-six Brazilian players were evaluated on an official pitch using three-dimensional kinematics to measure (300 Hz) ball velocity (Vball), foot velocity (Vfoot), Vball/Vfoot ratio, last stride length, and distance between the support foot and the ball. Simultaneously, a two-dimensional procedure was also conducted to compute (60 Hz) the mean radial error, bivariate variable error, and accuracy. Possible age-related differences were assessed through one-way analysis of variance and magnitude-based inferences. Results: Ball velocity increased by 103% (p < .001, η2 = .39) from the U11 age group (48.54 ± 8.31 km/hr) to the U20 age group (98.74 ± 16.35 km/hr). Foot velocity presented a 59% increase (p < .001, η2 = .32) from the U11 age group (49.08 ± 5.16 km/hr) to U20 (78.24 ± 9.49 km/hr). This finding was due to improvement in the quality of foot–ball impact (Vball/Vfoot ratio) from U11 (0.99 ± 0.13 a.u.) to U20 (1.26 ± 0.11 a.u.; p < .001, η2 = .25). Parameters such as mean radial error and accuracy appeared to be impaired during the growth spurt (U13–U15). Last stride length was correlated, low to moderately high, with Vball in all age groups (r = .36–.79). Conclusions: In summary, we concluded that simple biomechanical parameters of kicking performance presented distinct development. These results suggest that different training strategies specific for each age group could be applied. We provide predictive equations to aid coaches in the long-term monitoring process to develop the kick in soccer or search for talented young players.

Discovery of a Sweet Spot on the Foot with a Smart Wearable Soccer Boot Sensor That Maximizes the Chances of Scoring a Curved Kick in Soccer.

This paper provides the evidence of a sweet spot on the boot/foot as well as the method for detecting it with a wearable pressure sensitive device. This study confirmed the hypothesized existence of sweet and dead spots on a soccer boot or foot when kicking a ball. For a stationary curved kick, kicking the ball at the sweet spot maximized the probability of scoring a goal (58–86%), whereas having the impact point at the dead zone minimized the probability (11–22%). The sweet spot was found based on hypothesized favorable parameter ranges (center of pressure in x/y-directions and/or peak impact force) and the dead zone based on hypothesized unfavorable parameter ranges. The sweet spot was rather concentrated, independent of which parameter combination was used (two- or three-parameter combination), whereas the dead zone, located 21 mm from the sweet spot, was more widespread.

Novel mathematical model to estimate ball impact force in soccer

To assess ball impact force during soccer kicking is important to quantify from both performance and chronic injury prevention perspectives. We aimed to verify the appropriateness of previous models used to estimate ball impact force and to propose an improved model to better capture the time history of ball impact force. A soccer ball was fired directly onto a force platform (10 kHz) at five realistic kicking ball velocities and ball behaviour was captured by a high-speed camera (5,000 Hz). The time history of ball impact force was estimated using three existing models and two new models. A new mathematical model that took into account a rapid change in ball surface area and heterogeneous ball deformation showed a distinctive advantage to estimate the peak forces and its occurrence times and to reproduce time history of ball impact forces more precisely, thereby reinforcing the possible mechanics of ‘footballer’s ankle’. Ball impact time was also systematically shortened when ball velocity increases in contrast to practical understanding for producing faster ball velocity, however, the aspect of ball contact time must be considered carefully from practical point of view.

Differences in soccer kicking type identified using principal component analysis

Soccer kicks are characterized by segmental and joint rotations in multiple planes, where large discrepancies between two- and three-dimensional analyses for angular measurements of soccer kicks exist. The aim of this study was to clarify the differences in motions of the lower limbs and the pelvis required to achieve a shot without rotations as compared with an instep kick. Kinematic parameters obtained from non-rotational shots and instep kicks were analyzed using principal component analysis (PCA). The results clearly demonstrated that the PCA identified the differences in the instep kick and the non-rotational shot relative to the kinematic motions of the lower limbs and the pelvis. These findings suggest that the key issue for executing the NR shot is achieving a straight-line foot trajectory in the impact phase.

Fatigue Impact to Mechanical Movement of Maximal Instep Kicking in Soccer

The fatigue factor can restrict and disrupt the player’s decision-making and also obstruct player’s cognition during the match. It is found that fatigue can decrease the speed of the ball while kicking after being trained (protocol fatigue training). Meanwhile, another finding comes out different that the speed of the ball doesn’t change significantly while playing in simulation match. The purpose of this study is to find out more comprehensively the level of fatigue to the change of movement’s mechanism that occurs in instep kicking technique. The method used in this study is quantitative descriptive. The independent variable consist of fatigue index levels (normal and maximum). Meanwhile, the dependent variables are the momentum of the ball, ground reaction force, and impulse. The result of the study shows that there is a significant difference in the speed of the ball between normal condition and fatigue. Furthermore, the result of Ground Reaction Force (GRF) and impulse shows significant difference.

Bilateral Leg Differences in Soccer Kick Kinematics Following Exhaustive Running Fatigue

Background: Understanding fatigue effects on kicking technique with both legs would allow coaches to design soccer-specific training programs. Objectives: The purpose of the present study was to examine whether fatigue effects on soccer kick kinematics would differ between the preferred and the non-preferred leg. Methods: Ten adult amateur male players (age: 24.5 ± 5.8 yrs; height: 179.2 ± 4.3 cm; mass: 79.3 ± 5.4 kg; training age: 11.5 ± 2.9 yrs) performed two instep kicks with their preferred and non-preferred leg prior to and after running on a treadmill till exhaustion. Three-dimensional kinematics were collected pre and post-fatigue. Results: Analysis of variance indicated a statistically significant decline in ball speed after fatigue for both legs (P < 0.05). Maximum linear and angular velocity for all joints was significantly lower post fatigue for both preferred and non-preferred leg (P < 0.05). Similarly, alterations on joint kinematics were evident for both legs. Conclusions: Soccer kick performance declined after fatigue and this reduction was higher for the non-preferred leg compared to preferred leg performance. These findings indicate the need for specific exercises during the training process in order to reduce the effects of fatigue, especially for the non-preferred leg.

An Investigation of Ball Velocity between the Instep and Inside of the Foot Kicks of University Soccer Players

Purpose: The Purpose of this study was to investigate ball velocity of instep and inside foot kicks of university level soccer players. Method: The participants sample consisted twenty university soccer players from Fiji National University, Fiji. All participants have minimum of four years playing experience. The participants delivered instep and inside foot kicks using the right leg. Participants wore a complete soccer kit. Two cameras were used for this study. The cameras intersected each other perpendicularly on sagittal and frontal plans. Motion Analysis Tools (MAT) software was used to determine the ball velocity and IBM SPSS 30 was used to calculate pair t-test involving two tail tests to determine the significant difference of the ball velocity of university soccer players. Results: The results of the study indicate that the mean velocity of instep soccer kick is higher than the mean velocity of the inside foot soccer kicks. A significant difference also exists at the .05 level between the instep and the inside foot soccer kicks of the participants. Conclusion: It can be concluded that the inside foot kick resulted in a lower ball velocity than the instep kick on the part of the university level players.

Construct validity of tests that measure kick performance for young soccer players based on cluster analysis: exploring the relationship between coaches rating and actual measures.

The main aim of this study was to verify the relationship between the classification of coaches and actual performance in field tests that measure the kicking performance in young soccer players, using the K-means clustering technique. Twenty-three U-14 players performed 8 tests to measure their kicking performance. Four experienced coaches provided a rating for each player as follows: 1: poor; 2: below average; 3: average; 4: very good; 5: excellent as related to three parameters (i.e. accuracy, power and ability to put spin on the ball). The scores interval established from k-means cluster metric was useful to originating five groups of performance level, since ANOVA revealed significant differences between clusters generated (P<0.01). Accuracy seems to be moderately predicted by the penalty kick, free kick, kicking the ball rolling and Wall Volley Test (0.44≤r≤0.56), while the ability to put spin on the ball can be measured by the free kick and the corner kick tests (0.52≤r≤0.61). Body measurements, age and PHV did not systematically influence the performance. The Wall Volley Test seems to be a good predictor of other tests. Five tests showed reasonable construct validity and can be used to predict the accuracy (penalty kick, free kick, kicking a rolling ball and Wall Volley Test) and ability to put spin on the ball (free kick and corner kick tests) when kicking in soccer. In contrast, the goal kick, kicking the ball when airborne and the vertical kick tests exhibited low power of discrimination and using them should be viewed with caution.