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1.
The aims of this study were 1) to analyse session-to-session variations in different external load measures and 2) to examine differences in within-session intervals across different small-sided game (SSG) formats in professional players. Twenty professional soccer players (mean ± SD; age 28.1 ± 4.6 years, height 176.7 ± 4.9 cm, body mass 72.0 ± 7.8 kg, and body fat 10.3 ± 3.8%) participated in 3v3, 4v4, and 6v6 SSGs under different conditions (i.e., touch limitations and presence of goalkeepers vs. free touch and ball possession drill) over three sessions. Selected external load measures—including total distance (TD), high-intensity running (HIR, distance covered > 14.4 km.h-1), high-speed running (HSR, distance covered > 19.8 km.h-1), and mechanical work (MW, accelerations and deceleration > 2.2 m.s2)—were recorded using GPS technology during all SSG sessions. Small to large standardized typical errors were observed in session-to-session variations of selected measures across SSGs. TD.min-1 showed less variability, having a coefficient of variation (CV) of 2.2 to 4.6%, while all other selected external load measures had CV values ranging from 7.2% to 29.4%. Trivial differences were observed between intervals in TD.min-1 and HIR.min-1 for all SSGs, as well as in HSR.min-1 and MW.min-1 for most SSG formats. No reductions or incremental trends in session-to-session variations were observed when employing touch limitations or adding goalkeepers. The increased noise observed in higher speed zones (e.g., high-speed running) suggests a need for more controlled, running-based conditional drills if the aim is greater consistency in these measures.  相似文献   

2.
The aim of this study was to examine the relationship between the playing level in soccer (i.e., amateur vs. professional players) and the physiological impact, perceptual responses, time-motion characteristics, and technical activities during various small-sided games (SSGs). Twenty international players (27.4 ± 1.5 years and 17.4 ± 0.8 km·h(-1) of vVO(2)max) and 20 amateur players of the fourth French division (26.3 ± 2.2 years and 17.0 ± 1.2 km·h(-1) of vVO(2)max) played 9 SSGs (i.e., 2 vs. 2, 3 vs. 3, and 4 vs. 4) in which the number of ball touches authorized by possession varied (1 ball touch authorized = 1T, 2 ball touches authorized = 2T, and Free Play = FP). Heart rate (HR), blood lactate ([La]), subjective perception of effort (rating of perceived exertion [RPE]), physical performance, and technical performance of all players were analyzed during all SSGs. Across the various SSGs, amateurs completed a lower percent of successful passes (p < 0.01), recorded higher RPE and [La] values, lost a greater amount of ball possessions (p < 0.001), and covered less total distance with respect to sprinting and high-intensity running (HIR). The HR responses, however, were similar when expressed as %HRmax and %HRreserve. The comparison of the professional and amateur soccer players' activities during SSGs showed that the playing level influenced the physiological responses, physical and technical activities. Consequently, this study has shown that the main differences between elite and amateur players within SSGs concerned their capacity to perform high-intensity actions (HIR and sprints) and execute various technical abilities (in particular number of ball lost per possession and percentage of successful passes).  相似文献   

3.
4.
The purpose of this study was to compare the effects of regular small-sided games (SSGreg) and SSGs combined with running drills (SSGcom) on players’ internal and external loads. Eighteen young male soccer players (average age: 18.2 ± 0.5 years) participated in 3 vs. 3 and 4 vs. 4 games, under both SSGreg and SSGcom conditions. SSGreg bouts were played for 4 minutes without additional running drills, while SSGcom bouts consisted of 3 min 30 s SSG and 15 s running before and after the bout, making the duration of each bout 4 minutes. During all SSGs, measurements of heart rate (HR) responses as well as distances covered in four different speed zones – walking (WLK), low-intensity (LIR), moderate-intensity (MIR) and high-intensity running (HIR) – were recorded. Technical characteristics were monitored during the SSGs, and the rating of perceived exertion (RPE) and blood lactate (La-) responses were determined at the end of each SSG condition. Compared to the SSGreg in both 3 vs. 3 and 4 vs. 4 formats, the SSGcom condition resulted in higher La- and RPE responses (p < 0.05), greater distance covered at MIR and HIR speeds and greater total distance (p < 0.05). The results of this study show that replacing 30 s within the 4-min bouts of SSGs (both 3- and 4-a-side) by 2 x 15 s of running drills is effective in increasing internal (La- and RPE) and external loads (MIR and HIR) without a significant decrease in total passes and successful passes in young soccer players.  相似文献   

5.
The purpose of this study was to compare the blood lactate (La-), heart rate (HR) and percentage of maximum HR (%HRmax) responses among the small-sided games (SSGs) in elite young soccer players. Sixteen players (average age 15.7 6 0.4 years; height 176.8 6 4.6 cm; body mass 65.5 6 5.6 kg; VO2max 53.1 6 5.9 ml · kg(-1) · min(-1); HRmax 195.9 6 7.4 b · min(-1)) volunteered to perform the YoYo intermittent recovery test and 6 bouts of soccer drills including 1-a-side, 2-a-side, 3-a-side, and 4-a-side games without a goalkeeper in random order at 2-day intervals. The differences in La-, HR and%HRmax either among the SSGs or among the bouts were identified using 4 x 6 (games x exercise bouts) 2-way analysis of variance with repeated measures. Significant differences were found on La-, HR, and %HRmax among the bouts (p ≤ 0.05). The 3-a-side and 4-a-side games were significantly higher than 1-a-side and 2-a-side games on HR and %HRmax (p ≤ 0.05), whereas the 1-a-side game significantly resulted in higher La- responses compared to other SSGs. This study demonstrated that physiological responses during the 1-a-side and 2-a-side games were different compared to 3-a-side and 4-a-side games. Therefore, it can be concluded that a decreased number of players results in increased intensity during SSGs including 6 bouts. These results suggest that coaches should pay attention on choosing the SSG type and the number of bouts to improve desired physical conditioning of elite young soccer players in soccer training.  相似文献   

6.
The aim of this study was to describe the team accumulated physical response per minute considering only the effective playing time (EPT) attending to different contextual and strategic variables in the Spanish Football First Division (LaLiga Santander). A sample of 2,959 performances was included in the analysis, considering a 4-year period of analysis (from 2016–17 to 2019–20). The physical variables were: total distance covered with (DTminPOS) and without (DTminNOpos) possession of the ball, and distance covered at > 21 km·h-1 with possession (DT21minPOS) and without (DT21minNOpos). Two contextual variables, i.e. Place (Home/Away) and Score (Lost/Draw/Win), and two strategic variables, i.e. level of effective playing time (LevelETP) and level of possession of the ball (LevelPOS), were analysed. The teams ran more without possession of the ball than with possession; nevertheless, the teams that had less possession of the ball had higher values in the distance covered at > 21 km·h-1 with possession of the ball and vice versa. Furthermore, the strategic variables also had influence on the physical response (DT and DT21) of the teams,LevelETP and LevelPOS, although with interactive effects: longer playing time, less accumulated distance, and greater possession, greater accumulated distance in the defensive phase, both per min. The findings of this study may offer important practical implications to practitioners in order to assess physical performances of the players in matches, because it is crucial to integrate in the analysis the different contextual and strategic variables where the match has taken place to assess performances of the teams.  相似文献   

7.
The aim of this study was (i) to evaluate whether homocysteine (Hcy), total antioxidant status (TAS), and biological markers of muscle injury would be affected by time of day (TOD) in football players and (ii) to establish a relationship between diurnal variation of these biomarkers and the daytime rhythm of power and muscle fatigue during repeated sprint ability (RSA) exercise. In counterbalanced order, 12 football (soccer) players performed an RSA test (5 x[6 s of maximal cycling sprint + 24 s of rest]) on two different occasions: 07:00-08:30 h and 17:00-18:30 h. Fasting blood samples were collected from a forearm vein before and 3-5 min after each RSA test. Core temperature, rating of perceived exertion, and performances (i.e., Sprint 1, Sprint 2, and power decrease) during the RSA test were significantly higher at 17:00 than 07:00 h (p < .001, p < .05, and p < .05, respectively). The results also showed significant diurnal variation of resting Hcy levels and all biological markers of muscle injury with acrophases (peak times) observed at 17:00 h. These fluctuations persisted after the RSA test. However, biomarkers of antioxidant status' resting levels (i.e., total antioxidant status, uric acid, and total bilirubin) were higher in the morning. This TOD effect was suppressed after exercise for TAS and uric acid. In conclusion, the present study confirms diurnal variation of Hcy, selected biological markers of cellular damage, and antioxidant status in young football players. Also, the higher performances and muscle fatigue showed in the evening during RSA exercise might be due to higher levels of biological markers of muscle injury and lower antioxidant status at this TOD.  相似文献   

8.
Despite the large number of studies that have examined the acute effects of different warm up modalities (WU) on physical performance, none of them have documented the time course of potential performance recovery in tennis players. The aim of this study was twofold: (a) to analyze and compare the acute effects of two different WU modalities (traditional WU [TWU] and dynamic WU [DWU]) on physical performance (i.e., CMJ, sprint, serve speed and accuracy) in elite junior players, as well as (b) to monitor the time course of any WU-induced changes after 30 and 60 min of simulated match-play. Twelve junior elite players completed both WUs modalities (TWU and DWU) in a counterbalanced order on separate days. In each experimental session, counter movement jump (CMJ), 20-m sprint, tennis serve speed and accuracy tests were performed before (immediately after TWU or DWU) during (30 min) and after 60 min of a simulated match play. Measures were compared via four factorial (WU intervention and time) repeated measures ANOVAs. There were main effects of WU (TWU and DWU) throughout the time for all the variables analysed. The results indicate that DWU routine led to significantly faster 20 m sprint times and higher CMJs as well as faster and more accurate tennis serves at both post warm-up and 30 min match-play testing moments in comparison with the scores reported by the TWU routine (p < 0.05; positive effects with a probability of >75–99%). No significant intergroup differences were found at 60-min match-play testing moment in any variable (except for the 20 m sprint). Therefore, the findings of this study recommend for optimal performance in these elite tennis players, DWU routines should be performed prior to formal training and competition rather than TWU routines.  相似文献   

9.
Global positioning system (GPS) technology has improved the speed, accuracy, and ease of time-motion analyses of field sport athletes. The large volume of numerical data generated by GPS technology is usually summarized by reporting the distance traveled and time spent in various locomotor categories (e.g., walking, jogging, and running). There are a variety of definitions used in the literature to represent these categories, which makes it nearly impossible to compare findings among studies. The purpose of this work was to propose standard definitions (velocity ranges) that were determined by an objective analysis of time-motion data. In addition, we discuss the limitations of the existing definition of a sprint and present a new definition of sprinting for field sport athletes. Twenty-five GPS data files collected from 5 different sports (men's and women's field hockey, men's and women's soccer, and Australian Rules Football) were analyzed to identify the average velocity distribution. A curve fitting process was then used to determine the optimal placement of 4 Gaussian curves representing the typical locomotor categories. Based on the findings of these analyses, we make recommendations about sport-specific velocity ranges to be used in future time-motion studies of field sport athletes. We also suggest that a sprint be defined as any movement that reaches or exceeds the sprint threshold velocity for at least 1 second and any movement with an acceleration that occurs within the highest 5% of accelerations found in the corresponding velocity range. From a practical perspective, these analyses provide conditioning coaches with information on the high-intensity sprinting demands of field sport athletes, while also providing a novel method of capturing maximal effort, short-duration sprints.  相似文献   

10.
Monitoring workload is critical for elite training and competition, as well as preventing potential sports injuries. The assessment of external load in team sports has been provided with new technologies that help coaches to individualize training and optimize their team’s playing system. In this study we characterized the physical demands of an elite handball team during an entire sports season. Novel data are reported for each playing position of this highly strenuous body-contact team sport. Sixteen world top players (5 wings, 2 centre backs, 6 backs, 3 line players) were equipped with a local positioning system (WIMU PRO) during fourteen official Spanish first league matches. Playing time, total distance covered at different running speeds, and acceleration variables were monitored. During a handball match, wings cover the greater distance by high-speed running (> 5.0 m·s-1): 410.3 ± 193.2 m, and by sprint (> 6.7 m·s-1): 98.0 ± 75.4 m. Centre backs perform the following playing position that supports the highest speed intensities during the matches: high-speed running: 243.2 ± 130.2 m; sprint: 62.0 ± 54.2 m. Centre backs also register the largest number of high-intensity decelerations (n = 142.7 ± 59.5) compared to wings (n = 112.9 ± 56.0), backs (n = 105.2 ± 49.2) and line players: 99.6 ± 28.9). This study provides helpful information for professional coaches and their technical staff to optimize training load and individualize the physical demands of their elite male handball players depending on each playing position.  相似文献   

11.
The aim of this study was (i) to evaluate whether homocysteine (Hcy), total antioxidant status (TAS), and biological markers of muscle injury would be affected by time of day (TOD) in football players and (ii) to establish a relationship between diurnal variation of these biomarkers and the daytime rhythm of power and muscle fatigue during repeated sprint ability (RSA) exercise. In counterbalanced order, 12 football (soccer) players performed an RSA test (5?×?[6 s of maximal cycling sprint?+?24 s of rest]) on two different occasions: 07:00–08:30?h and 17:00–18:30?h. Fasting blood samples were collected from a forearm vein before and 3–5?min after each RSA test. Core temperature, rating of perceived exertion, and performances (i.e., Sprint 1, Sprint 2, and power decrease) during the RSA test were significantly higher at 17:00 than 07:00?h (p?<?.001, p?<?.05, and p?<?.05, respectively). The results also showed significant diurnal variation of resting Hcy levels and all biological markers of muscle injury with acrophases (peak times) observed at 17:00?h. These fluctuations persisted after the RSA test. However, biomarkers of antioxidant status' resting levels (i.e., total antioxidant status, uric acid, and total bilirubin) were higher in the morning. This TOD effect was suppressed after exercise for TAS and uric acid. In conclusion, the present study confirms diurnal variation of Hcy, selected biological markers of cellular damage, and antioxidant status in young football players. Also, the higher performances and muscle fatigue showed in the evening during RSA exercise might be due to higher levels of biological markers of muscle injury and lower antioxidant status at this TOD. (Author correspondence: )  相似文献   

12.
Success in rugby league football seems heavily reliant on players possessing an adequate degree of various physical fitness qualities, such as strength, power, speed, agility, and endurance, as well as the individual skills and team tactical abilities. The purpose of this study was to describe and compare the lower body strength, power, acceleration, maximal speed, agility, and sprint momentum of elite first-division national rugby league (NRL) players (n = 20) to second-division state league (SRL) players (n = 20) players from the same club. Strength and maximal power were the best discriminators of which players were in the NRL or SRL squads. None of the sprinting tests, such as acceleration (10-m sprint), maximal speed (40-m sprint), or a unique 40-m agility test, could distinguish between the NRL or SRL squads. However, sprint momentum, which was a product of 10-m velocity and body mass, was better for discriminating between NRL and SRL players as heavier, faster players would possess better drive forward and conversely be better able to repel their opponents' drive forward. Strength and conditioning specialists should therefore pay particular attention to increasing lower body strength and power and total body mass through appropriate resistance training while maintaining or improving 10-m sprint speed to provide their players with the underlying performance characteristics of play at the elite level in rugby leagues.  相似文献   

13.
14.
The study aimed to evaluate the effects of 1 vs. 2 sessions per week of equal-volume sprint training on explosive, high-intensity and endurance-intensive performances among young soccer players. Thirty-six young male soccer players were randomly divided into 2 experimental groups that performed either a single weekly sprint training session (ST1, n = 18, age: 17.2 ± 0.8 years) or two weekly sprint training sessions (ST2, n = 18; age: 17.1 ± 0.9 years) of equal weekly and total volume, in addition to their regular soccer training regimen. Linear sprinting (10 m, 20 m, 30 m, and flying 10 m), T-test agility, countermovement jump (CMJ) and maximal oxygen consumption were assessed one week before (T1), in the middle (T2) and immediately after the 10 weeks of training (T3). A large magnitude and statistically significant main effect for time was found in all the assessed variables after both training interventions (all p < 0.001; ES ≥ 0.80). No main effect was observed between the 2 groups at any time in linear sprinting, T-test or CMJ test (p > 0.05; ES < 0.20). A significant interaction effect (F = 4.05; p = 0.04, ES = 0.21) was found for maximal oxygen consumption with ST2 inducing better performance than ST1 (p = 0.001; ES = 1.11). Our findings suggested that the two sprint training frequencies were effective in enhancing explosive, high-intensity and endurance-intensive performances. However, it is recommended for coaches and fitness coaches to use a biweekly sprint training modality as it was found to be more effective in improving endurance-intensive performance.  相似文献   

15.
A major use of small-sided games (SSGs) in soccer training is the concomitant development of game-specific aerobic fitness. We hypothesize that the SSG formats of 2 vs. 2, 3 vs. 3, and 4 vs. 4 players reveal game-like intensities and therefore are most adequate to increase game-specific aerobic fitness. Heart rate (HR), percentage of maximum heart rate (HRmax), blood lactate concentration (La), and time-motion characteristics of 17 elite male youth soccer players (aged 14.9 ± 0.7 years, V[Combining Dot Above]O2max 61.4 ± 4.5 ml·kg·min, HRmax 199.6 ± 7.3 b·min) were collected by global positioning systems while performing the SSG formats. Repeated-measures analysis of variance and effect sizes were calculated to demonstrate the differences between SSG formats. Highest physiological responses were obtained in 2 vs. 2 (HR: 186 ± 7 b·min, HRmax: 93.3 ± 4.2%, La: 5.5 ± 2.4 mmol·L) followed by 3 vs. 3 (HR: 184 ± 8 b·min, HRmax: 91.5 ± 3.3%, La: 4.3 ± 1.7 mmol·L) and 4 vs. 4 (HR: 179 ± 7 b·min, HRmax 89.7 ± 3.4%, La: 4.4 ± 1.9 mmol·L). Pronounced differences were found for most physiological parameters and for time spent in the speed zones "walking" (<5.3 km·h), "moderate-speed running" (10.3-13.9 km·h), and "maximum sprinting" (≥26.8 km·h). The findings suggest that all the formats reveal game-like intensities and are suitable for aerobic fitness improvements. However, we found pronounced demands on the anaerobic energy supply in 2 vs. 2, whereas 3 vs. 3 and 4 vs. 4 remain predominantly on an aerobic level and differ mainly in the HR response. We suggest using 3 vs. 3 for soccer-specific aerobic fitness training.  相似文献   

16.
Volleyball players need to sprint and change direction during a match. Lower-body power, often measured by jump tests, could contribute to faster movements. How different jumps relate to linear and change-of-direction (COD) speed has not been analyzed in Division I (DI) collegiate women’s volleyball players. Fifteen female volleyball players completed the vertical jump (VJ), two-step approach jump (AppJ), and standing broad jump (SBJ). Peak power and power-to-body mass ratio (P:BM) were derived from VJ and AppJ height; relative SBJ was derived from SBJ distance. Linear speed was measured via a 20-m sprint (0–10 and 0–20 m intervals); COD speed was measured using the pro-agility shuttle. Pearson’s correlations (p < 0.05) calculated relationships between the power variables, and speed tests. There were no significant relationships between the power variables and the 0–10 m sprint interval. Greater VJ height (r = -0.534) and P:BM (r = -0.557) related to a faster 0–20 m sprint interval. This be due to a greater emphasis on the stretch-shortening cycle to generate speed over 20 m. However, although a 20-m sprint may provide a measure of general athleticism, the distance may not be specific to volleyball. This was also indicated as the AppJ did not relate to any of the speed tests. Nonetheless, VJ height and P:BM, and SBJ distance and relative SBJ, all negatively correlated with the proagility shuttle (r = -0.548 to -0.729). DI women’s collegiate volleyball players could develop absolute and relative power in the vertical and horizontal planes to enhance COD speed.  相似文献   

17.
The objective of this study was to determine the relationship between specific performance measures and hockey skating speed. Thirty competitive secondary school and junior hockey players were timed for skating speed. Off-ice measures included a 40-yd (36.9-m) sprint, concentric squat jump, drop jump, 1 repetition maximum leg press, flexibility, and balance ratio (wobble board test). Pearson product moment correlations were used to quantify the relationships between the variables. Electromyographic (EMG) activity of the dominant vastus lateralis and biceps femoris was monitored in 12 of the players while skating, stopping, turning, and performing a change-of-direction drill. Significant correlations (p < 0.005) were found between skating performance and the sprint and balance tests. Further analysis demonstrated significant correlations between balance and players under the age of 19 years (r = -0.65) but not those over 19 years old (r = -0.28). The significant correlations with balance suggested that stability may be associated with skating speed in younger players. The low correlations with drop jumps suggested that short contact time stretch-shortening activities (i.e., low amplitude plyometrics) may not be an important factor. Electromyographic activities illustrated the very high activation levels associated with maximum skating speed.  相似文献   

18.
The purpose of this study was to investigate the time course of adaptations to training in young (i.e., <15 years) and older (i.e., <18 years) junior rugby league players. Fourteen young (14.1 +/- 0.2 years) and 21 older (16.9 +/- 0.3 years) junior rugby league players participated in a 10-week preseason strength, conditioning, and skills program that included 3 sessions each week. Subjects performed measurements of standard anthropometry (i.e., height, body mass, and sum of 7 skinfolds), muscular power (i.e., vertical jump), speed (i.e., 10-m, 20-m, and 40-m sprint), agility (505 test), and estimated maximal aerobic power (i.e., multistage fitness test) before and after training. In addition, players underwent a smaller battery of fitness tests every 3 weeks to assess the time course of adaptation to the prescribed training stimulus. During the triweekly testing sessions, players completed assessments of upper-body (i.e., 60-second push-up, sit-up, and chin-up test) and lower-body (i.e., multiple-effort vertical jump test) muscular endurance. Improvements in maximal aerobic power and muscular endurance were observed in both the young and the older junior players following training. The improvements in speed, muscular power, maximal aerobic power, and upper-body muscular endurance were greatest in the young junior players, while improvements in lower-body muscular endurance were greatest in the older junior players. These findings demonstrate that young (i.e., <15 years) and older (i.e., <18 years) junior rugby league players adapt differently to a given training stimulus and that training programs should be modified to accommodate differences in maturational and training age. In addition, the results of this study provide conditioning coaches with realistic performance improvements following a 10-week preseason strength and conditioning program in junior rugby league players.  相似文献   

19.
This study aimed to analyse the influence of different contextual factors (i.e., defensive style and game outcome) on basketball players’ external load during games-based drills using ultrawideband (UWB) technology. Fourteen male professional basketball players belonging to an elite reserve Spanish club (ACB) participated in this study. The games-based drills consisted of one bout of 10 min played 5vs5 in which players were instructed to use man-to-man defence (MMD) and/or zone defence (ZD). In addition, the final game outcome (i.e., winning or losing) of the game-based drill was registered. External load variables per minute were recorded: total distance covered, distance covered in different speed zones, distance covered while accelerating and decelerating, maximum speed, steps, jumps and player load. A two-way ANOVA with the Tukey post hoc test was used to assess the impact of defensive style and final game outcome and the interaction of both factors on the external load encountered by basketball players. No meaningful differences (unclear) were found in the external loads between playing with MMD and with ZD and between winning and losing teams except for greater distance at high-speed running (18.0–24.0 km·h-1) in winning teams (p < 0.05, ES = 0.68, moderate). A significant interaction between defensive style and final game outcome was found for high decelerations (> -2 m·s-2) (p = 0.041; ES = 0.70) and jumps (p = 0.037; ES = 0.68). These results could potentially help coaching staff in prescribing an appropriate workload during basketball-specific game-based drills, and ultimately enhance the match performance.  相似文献   

20.
This study aimed to quantify the time-motion demands and intra-team movement synchronization during the pre-season matches of a professional soccer team according to the opposition level. Positional data from 20 players were captured during the first half of six pre-season matches of a Portuguese first league team. Time-motion demands were measured by the total distance covered and distance covered at different speed categories. Intra-team coordination was measured by calculating the relative phase of all pairs of outfield players. Afterwards, the percentage of time spent in the −30° to 30° bin (near-in-phase mode of coordination) was calculated for each dyad as a measure of space-time movement synchronization. Movement synchronization data were analyzed for the whole team, according to each dyad average speed and by groups of similar dyadic synchronization tendencies. Then, these data were compared according to the opponent team level (first league; second league; amateurs). Time-motion demands showed no differences in total distance covered per opposition levels, while matches opposing teams of superior level revealed more distance covered at very high intensity. Competing against superior level teams implied more time in synchronized behavior for the overall displacements and displacements at higher intensities. These findings suggest that playing against higher-level opponents (1st league teams) increased time-motion demands at high intensities in tandem with intra-team movement synchronization tendencies.  相似文献   

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