Match Running Research Articles

Does player age influence match physical performance? A longitudinal four-season analysis in Spanish Soccer LaLiga.

This study aims to analyse the evolution of match running performance in relation to the age distribution of professional soccer players using a large-scale analysis. An explorational-longitudinal and retrospective study was designed and a total of 36,883 individual match observations were collected on outfield players competing across four consecutive Spanish LaLiga seasons (from 2015/16 to 2018/19), using an optical tracking system (ChyronHego). Soccer players were divided into 3 age groups: young (18-24 years old), middle-aged (25-30 years old), and seniors (31-41 years old). Relative total distance (TD/min), distance covered at 21-24 km · h-1 (HIRD/min), and > 24 km · h-1 per minute (VHIRD/min) were analysed; also, the number of efforts at 21-24 km · h-1 (Sp21) and > 24 km · h-1 (Sp24) were taken into consideration. Seasons were divided into four phases (P): P1 (matches 1-10), P2 (11-19), P3 (20-29), and P4 (30-38). The results showed that young players covered significantly greater TD, HIRD and VHIRD than the rest of the players (p < .05) in all season phases. In addition, TD significantly decreased along season phases in all player age group (p < .01). Crucially, young players performed significantly greater numbers of Sp21 and Sp24 than the rest of the players (p < .05) in all season phases. In addition, Sp21 and SP24 significantly decreased in middle-aged (p < .01) and senior players (p < .05) across the seasons. This study demonstrated that players' match running performance decreases with increasing years, especially in high-intensity running distances.

Match running performance characterizing the most elite soccer match-play.

In order to identify match running performance (MRP) characterizing the most elite soccer match-play, this study aimed to examine position-specific differences in the MRP of players competing in "big five" (BFLTs) and "non-big five" league teams (N-BFLTs). The data were obtained from 24 teams (BFLTs; n = 14, N-BFLTs; n = 10) during the UEFA Champions League (UCL) matches (n = 20) in the 2020/21 season using a semiautomatic video system. The differences in MRP between BFLTs and N-BFLTs, while controlling for contextual factors, were examined using linear mixed model. No differences in overall MRP between fullbacks, central midfielders, wide midfielders and forwards from BFLTs and their peers from N-BFLTs were found, while only central defenders from BFLTs covered more high-intensity running than central defenders from BFLTs (moderate effects size). For players on all playing positions from BFLTs, total- and low-intensity distance covered were lower in offensive phase of game and greater in defensive phase of game compared to their peers from N-BFLTs (all large effect sizes). This study demonstrated that the most elite match-play in soccer is characterized by increased efforts in defensive phase of game, and decreased efforts in offensive phase of game. Soccer training programmes should be adapted accordingly.

Factors affecting match running performance in elite soccer: Analysis of UEFA Champions League matches.

This study aimed to examine the independent effect of different match-related factors on match running performance (MRP) in elite soccer. Players' MRPs (n = 244) were collected during UEFA Champions League (UCL) group stage matches in the 2020-21 season. All MRP data were collected by the semi-automatic optical system InStat Fitness (InStat Limited, Limerick, Republic of Ireland). Match-related factors included match outcome, team quality, match location, opponent quality and difference in team quality, while MRP included cumulative and relative measures of total distance (TD and R-TD), low-intensity running (LIR and R-LIR) (≤ 4 m/s), moderate-intensity running (MIR and R-MIR) (4-5.5 m/s) and high-intensity running (HIR and R-HIR) (≥ 5.5 m/s). Linear mixed models were used to examine the collective effect of match-related factors on MRPs when controlling for between-player, between-playing position and between-team variation. The main findings were that match outcome was associated with reduced HIR (d = -0.38, p = 0.04), match location was associated with increased TD, R-TD, LIR and R-LIR (d = 0.54-0.87, all p < 0.01), while team quality, opponent quality and difference in team quality were not associated with MRP. These results show that (i) winning UCL matches was not strongly influenced by players' physical performance, (ii) away UCL matches were characterized by a slower match pace and greater match volume, and (iii) players' physical performance was similar irrespective of playing either in or against high- or low-quality teams. The findings from this study may help soccer coaches to ensure optimal physical preparation of players in elite soccer.

Phases of Match-Play in Professional Australian Football: Positional Demands and Match-Related Fatigue.

This study examined the influence of player position and match quarter on activity profiles during the phases of play in Australian Football. Global positioning satellite data was collected for one season from an Australian Football League team for nomadic, key position and ruck players (age: 24.8 ± 4.2 years, body mass: 88.3 ± 8.7 kg, height: 1.88 ± 0.8 m). Separate linear mixed models and effect sizes were used to analyse differences between positions and game quarter within each phase of play for values of distance, speed and metabolic power indices. There were clear differences between positions for low-speed running, high-speed running, total distance and average speed. Nomadic players generally recorded the highest match running outputs, followed by key position players and ruckmen. Within each position, offence and defence involved the highest intensities, followed by contested play and then stoppage periods. Across the four quarters, there were small to large reductions in average speed, high-speed running, high power and energy expenditure during offence, defence and contested play, but not during stoppages. Accordingly, conditioning staff should consider the intermittent intensities of the phases of match-play for each position to optimally prepare players for competition. Reductions in match intensities were evident during active periods of play providing implications for real-time monitoring to optimise the timing of rotations.

Effects of substitute allowance on match activity characteristics in Japanese professional football across 2019, 2020, and 2021 seasons

ABSTRACT This study aimed to examine the effects of substitute player allowance per match on running performance in Japanese professional football over three consecutive seasons with different numbers of maximum substitutes. Match running performance was obtained from all outfield players in the official matches of the 1st Division of the Japan Professional Football League over three seasons (2019/2020/2021; 22291 player files) by a 4th generation TRACAB® system which provided the total distance covered (TD) and the number of sprinting runs (SP; ≥24.0 km/h for≥1.0 s). The players were divided according to play time: full match (STA), replaced during match (REP), and substitutes during match (SUB). The number of SUBs increased significantly from 2019 to 2021 (p < 0.05). SUB had a significantly higher average speed than STA and REP. The analysis of covariance with the number of recovery days, ambient temperature, and relative humidity as covariates revealed that the TD and SP significantly differed based on the number of SUBs (p < 0.05). Stepwise regression analysis showed that the number of SUBs significantly contributed to the TD and SP. These results suggest that the new law, which increased the maximum SUB allowance from three to five, improved the match running performance in Japanese professional football.

An analysis of the relationship between critical velocity and anaerobic speed reserve with match running profile in football

Background and Study Aim. The aim of this study was to analyse the relationship between critical velocity (CV) and anaerobic speed reserve (ASR) with match running profile in football.&#x0D; Material and Methods. The research group consisted of fifteen young male football players (n=15, age=16.60±0.51 years, height=177.40±5.25 cm, weight=67.20±5.52 kg, body mass index=21.32±0.96 kg/m2). Yo-Yo intermittent recovery level 1 test (Yo-Yo IRT) was performed to determine maximal aerobic speed (MAS). Maximal sprint speed (MSS) was determined by 30-meter sprint test. CV and ADC parameters were obtained by linear regression model (Lin-TD: linear total distance model) between the covered distance and running duration in 800-meter and 2400-meter running tests. A 90-minutes football match was played to determine the subjects’ match running profile (covered distance in every running category), which was examined by means of a global positioning system (GPS) device in five running categories (walking: 0-6.9 km/h, low intensity running: 7-12.9 km/h, middle intensity running: 13-17.9 km/h, high intensity running: 18-20.9 km/h, sprint: &gt;21 km/h). Correlation analysis and multiple linear regression analysis was employed to analyse the collected data.&#x0D; Results. It was found that CV was significantly and positively correlated with total running distance as well as low and middle intensity running (p&lt;0.05). A significant and negative correlation was found between ASR and all match running profiles (p&lt;0.05). Both CV and ASR were significant predictors of high intensity running, maximum running speed and total running distance during match (p&lt;0.05). However, while CV was a significant predictor of sprint running, ASR significantly predicted walking (p&lt;0.05).&#x0D; Conclusions. Consequently, it may be concluded that in football, aerobic fitness is positively correlated to CV and negatively to ASR.

Match Running Performance in UEFA Champions League: Do More Successful Teams Really Run Less?

It is often hypothesized that more successful teams from elite football competitions achieve lower match running performance (MRP) than less successful teams. However, the results of previous studies investigat- ing the associations between MRP and different success indicators are inconsistent. The main objective of this study was to identify the association between teams’ MRP and the UEFA club coefficient as an indicator of long-term success in highest-level football. Individual MRPs (n=547) of 378 outfield players were jointly evaluated into the team MRP and used as cases in this study. All data were collected by the semi-automatic optical video system InStat Fitness from matches (n=20) of the UEFA Champions League group stage (UCL) in the 2020/2021 season. MRP variables included total distance covered and distance covered in different speed zones: walking (&lt;7.1 km/h), jogging (7.2–14.3 km/h), running (14.4–19.7 km/h), high-speed running (19.8–5.1 km/h), and sprinting (&gt;25.2 km/h). Pearson’s correlation coefficient was used to identify the association be- tween the teams’ MRP and the UEFA club coefficient. Results indicated that the UEFA club coefficient was positively and negatively associated with sprinting and jogging distance covered, respectively. These findings show that teams with a higher UEFA club coefficient performed a lower amount of running at low intensity and a greater amount of running at maximal intensity, suggesting that teams are achieving greater long-term success in highest-level football play at a higher game pace.

Decline in Running Performance in Highest-Level Soccer: Analysis of the UEFA Champions League Matches.

Simple SummaryHighest-level soccer players reduce match running performance towards the end of matches, with TD being greater reduced than HIR. As players do not reduce their MRP in the latest stages of the second half, and that influence of situational factors was not observed, it seems that the decline of match running performance in highest-level soccer may not be a consequence of fatigue or situational factors but of pacing strategies.It is widely recognized that there is a decline in match running performance (MRP) towards the end of matches. To clarify whether it is primarily a consequence of fatigue, pacing or situational influences, this study aimed to examine MRP across 15-min match periods for players on different playing positions. Players’ MRP (n = 244) were examined from the UEFA Champions League matches (n = 20) using a semiautomatic optical tracking system. Linear mixed models for repeated measures were adjusted to analyze MRP over the six 15-min match periods while controlling the influence of situational factors. No effects of match outcome, match location, team, and opponent quality on total distance (TD) and high-intensity running (HIR) for players in all playing positions were found (F = 0.03–2.75; all p > 0.05). Significant differences in TD (F = 17.57–53.01; η2 = 0.39–0.52, all large effect sizes) and HIR (F = 3.67–7.64; η2 = 0.05–0.19, small to medium effect sizes) among six 15-minute match periods were found for players in all playing positions. In addition, players in all playing positions covered less TD (d = 1.41–2.15, large to very large effect sizes) and HIR (d = 0.16–0.6, trivial to medium effect sizes) in the last compared to the first 15-min match period. No differences in TD and HIR between the last two match periods in the second half were observed. This study confirmed that soccer players reduce MRP towards the end of matches, and suggest that the decline of MPR in highest-level soccer may be a consequence of pacing strategies.

The effect of team formation on match running performance in UEFA Champions League matches: implications for position-specific conditioning

ABSTRACT This study aimed to determine the effect of team formation on position-specific match running performance (MRP) at highest-level football. Players’ MRP (n = 226) was observed in four team formations: 3-5-2 (n = 24), 4-4-2 (n = 44), 4-2-3-1 (n = 77) and 4-3-3 (n = 81). Central defenders in the 3-5-2 formation achieved a greater amount of high-intensity running distance than in the 4-3-3 formation (mean difference (MD) [95% confidence interval] = 144 m [12, 267], medium ES). Fullbacks in the 4-4-2 formation covered less total distance than in 3-5-2 (MD = −762 m [−1431, −94], large ES) and 4-2-3-1 (MD = −662 m [−1055, −269], medium ES). Central midfielders’ total distance in the 4-4-2 formation was lower than that in the 3-5-2 (MD = −645 m [−79, −1211], medium ES) and 4-3-3 (MD = −656 m [−1181, −132], medium ES) formations. Wide midfielders’ walking distance in the 4-4-2 formation was lower than that in the 4-3-3 (MD = −484 m [-742, -226], very large ES) and 4-2-3-1 (MD = −535 m [−789, −282], very large ES) formations. Forwards’ high-intensity running in the 4-2-3-1 formation was lower than that in the 4-3-3 (MD = −363 m [−613, −112], large ES) and 4-4-2 (MD = −396 m, [−688, −103], large ES) formations. These findings show that conditioning programs for players on all playing positions should be tailored according to the formations of their teams.

Physical Performance Indicators and Team Success in the German Soccer League

The aims of this study were (1) to determine the match running performance required by different teams based on their final ranking position and (2) to analyze the association between match running performance variables and team success at the end of the season. A total of 1,224 match observations from professional soccer teams competing during two consecutive seasons in the German Bundesliga were analyzed. In addition, the final league ranking position and the total of points obtained by each team at the end of the season were registered for the analysis of the association between team success and match running performance. The main findings were that high ranked teams covered the greatest total distance with ball possession, sprinting distance with ball possession, and completed the greatest number of sprinting actions with ball possession and maximal velocity. Moreover, total distance covered with possession of the ball and maximal velocity were the most important variables to predict the total of points obtained at the end of the season. Specifically, the relative contribution of total distance covered with ball possession to the total of points obtained was greater than maximal velocity. Training programs for professional soccer players should be focused on improving the sprint capacity and running with possession of the ball (e.g., transitional tasks and small-sided games). Moreover, this has implications for injury prevention, physical, psychological, and technical-tactical training since today’s soccer requires players to engage in repeated high-intensity actions, reach maximum speeds above 9 m/s, and develop technical-tactical coordination when running with the ball.

Maturity-Associated Differences in Match Running Performance in Elite Male Youth Soccer Players.

To investigate the influence of maturation on match running performance in elite male youth soccer players. A total of 37 elite male youth soccer participants from an English professional soccer academy from the U14s, U15s, and U16s age groups were assessed over the course of 1 competitive playing season (2018-2019). Relative biological maturity was assessed using percentage of predicted adult height. A global positioning system device was used between 2 and 30 (mean = 8 [5]) times on each outfield player. The position of each player in each game was defined as defender, midfielder, or attacker and spine or lateral. A total of 5 match-running metrics were collected total distance covered, high-speed running distance, very high-speed running distance, maximum speed attained, and number of accelerations. Relative biological maturity was positively associated with all global positioning system running metrics for U14s. The U15/16s showed variation in the associations among the global positioning system running metrics against maturity status. A multilevel model which allowed slopes to vary was the best model for all parameters for both age groups. In the U14 age group, advanced maturation was associated with greater high-speed running distance. However, maturation did not contribute toward variance in any of the indices of running performance in the U15/16s. In the U15/16 age group, significance was observed in the spine/lateral playing positions when undertaking actions that required covering distance at high speeds. Maturation appeared to have an impact on match-running metrics within the U14s cohort. However, within the U15/16s, the influence of maturation on match-running metrics appeared to have less of an impact.

Slow-Speed Compared With Fast-Speed Eccentric Muscle Actions Are Detrimental to Jump Performance in Elite Soccer Players In-Season.

To examine the effect of fast- versus slow-speed eccentric-muscle-action resistance training on lower-body strength, vertical jump height, sprint speed, and change-of-direction performance in elite soccer players during a competitive season. Twenty-two elite soccer players, from a single team, were randomly assigned to groups that undertook either 1- (fast speed) or 4-second (slow speed) eccentric resistance training during the in-season period. A 5-week program was conducted during an elite top-division European League soccer season. Performance measures including predicted 1-repetition-maximum back squat, countermovement jump, 20-m sprint, and change of direction were tested before and after the intervention period. Total match and training running distance and muscle soreness were also recorded during each week of the intervention. An analysis of covariance showed significant group effects (P = .01) for countermovement jump with a greater jump height in the 1-second fast-speed group postintervention (95% CI, 1.1-6.9cm). Despite an overall increase in 1-repetition maximum pretraining to posttraining (95% CI, 10.0-15.3kg, effect size 0.69), there were no significant differences (P > .05) between groups after the intervention. Similarly, there were no differences between groups for change of direction, 20-m sprint, or muscle soreness. Faster eccentric muscle actions may be superior for increasing movements in elite soccer players in-season.

Effects of Far-Infrared Radiation-Lamp Therapy on Recovery From Simulated Soccer Match Running Activities in Elite Soccer Players.

The authors investigated whether far-infrared radiation (FIR) lamp therapy would reduce muscle damage and enhance recovery from multiple soccer-match-related running activities. Twenty-four elite female soccer players (20-24y) were assigned into a FIR or a sham treatment group (n = 12/group). They performed a daily 90-minute Loughborough Intermittent Shuttle Test (LIST) for 6 consecutive days. Maximal voluntary contraction torque of the knee extensors (KEs) and flexors, muscle soreness, plasma creatine kinase activity, countermovement jump, and several other performance measures (eg,30-m dash, Yo-Yo Intermittent Recovery Test Level 1) were taken before the first LIST, 1 hour after each LIST, and 24, 48, 72, 96, and 120hours after the last LIST. All participants received a 30-minute FIR or sham treatment on KEs and knee flexors, respectively, at 2 hour after each LIST and 25, 49, 73, and 97hours after the last LIST. All measures changed significantly (P < .05) at 1 hour after the first LIST without difference (P > .05) between groups. Maximal voluntary contraction torque (eg,the largest decrease of KE for FIR: 13% [4%], sham: 25% [5%]), countermovement jump height (4% [3%] vs 14% [4%]), and other performance measures (eg,Yo-Yo Intermittent Recovery Test: 11% [5%] vs 26% [5%]) decreased less, and peak muscle soreness (eg,KE: 26 [9] vs 51 [18]mm) and plasma creatine kinase activity (172 [32] vs 1289 [610] IU/L) were smaller for the FIR than for the sham group (P < .05), and they returned to the baseline earlier (P < .05) for the FIR group. These results suggest that the FIR therapy provided potent effects on reducing accumulated muscle damage and enhancing recovery.

Modeling the Major Influencing Factor on Match Running Performance during the In-Season Phase in a Portuguese Professional Football Team.

The aim of this study was two-fold: (1) to analyze the influence of season phase (i.e., the start of the in-season and mid-in-season) on match running performance in a Portuguese professional football team; (2) to determine and model the main factor influencing match running performance during the in-season in this specific football team. Eighteen matches were collected by an 18 Hz global positioning system (GPS) from a professional Portuguese football team during the start of the in-season and mid-in-season. The match running performance was analyzed according to season phases, presenting significant differences in total distance (TD) (tlower bound = 4.71, p < 0.001; tupper bound = −2.22, p = 0.002), average speed (AvS) (tlower bound = 359.45, p < 0.001; tupper bound = −359.87, p < 0.001), and relative high speed running (rHSR) (tlower bound = 13.10, p < 0.001; tupper bound = −10.21, p < 0.001). The logistic regression showed TD (β = −1.59, z = −2.84, p = 0.005) and AvS (β = 2.68, z = −2.84, p = 0.007) as the major factors influencing match running performance during seasonal variation. Sprints and accelerations showed no significance for predicting match running performance during the season phases (β = −0.05 to 1.07, z = −0.95 to 1.07, p = 0.29 to 0.72). Current research confirms that lower and upper bounds should be used to quantify seasonal differences on match running performance. TD and AvS were described as the main factors influencing match running performance during the in-season phase. Thus, it is important to highlight the pace and volume of the game to maximize match running performance.

Clustering of match running and performance indicators to assess between- and within-playing position similarity in professional rugby league

ABSTRACT This study aimed to determine the similarity between and within positions in professional rugby league in terms of technical performance and match displacement. Here, the analyses were repeated on 3 different datasets which consisted of technical features only, displacement features only, and a combined dataset including both. Each dataset contained 7617 observations from the 2018 and 2019 Super League seasons, including 366 players from 11 teams. For each dataset, feature selection was initially used to rank features regarding their importance for predicting a player’s position for each match. Subsets of 12, 11, and 27 features were retained for technical, displacement, and combined datasets for subsequent analyses. Hierarchical cluster analyses were then carried out on the positional means to find logical groupings. For the technical dataset, 3 clusters were found: (1) props, loose forwards, second-row, hooker; (2) halves; (3) wings, centres, fullback. For displacement, 4 clusters were found: (1) second-rows, halves; (2) wings, centres; (3) fullback; (4) props, loose forward, hooker. For the combined dataset, 3 clusters were found: (1) halves, fullback; (2) wings and centres; (3) props, loose forward, hooker, second-rows. These positional clusters can be used to standardise positional groups in research investigating either technical, displacement, or both constructs within rugby league.

Match Running Performance in UEFA Champions League: Is There a Worthwhile Association with Team Achievement?

Simple SummaryThis study demonstrated that running performance (RP) is not the factor which defines team achievement in UEFA Champions League (UCL) group stage, indicating that the success of the teams who compete at the elite-level soccer is not influenced by pure physical performance. Although RP will not assure success, considering high physical demands observed in UCL, conditioning of the players who compete at the elite-level soccer should be at the highest possible level. These findings could help soccer coaches to optimize the training process of elite soccer players.Although running performance (RP) is considered an important factor of success in soccer, there is a lack of studies to examine this issue in highest-level soccer competition, such as UEFA Champions League (UCL). Therefore, the main objective of this study was to analyse players’ RP according to the achievement of their teams in UCL. In addition, position specific RP of the players who competed in the UCL was evaluated. The players’ RPs (n = 244) were collected during UCL group stage matches (n = 20) in the 2020/21 season using semiautomatic optical system InStat Fitness. A team’s achievement was defined by qualification of the team from the group stage into the knockout stage of the UCL, and by total group points earned at the end of the UCL group stage. Linear mixed models and Pearson’s correlation were used to examine differences in players’ RP according to the achievement of their teams. Results indicated (i) similar values of RP irrespective of whether the teams qualified from the group stage into the knockout stage of the UCL, and (ii) trivial-to-small correlations between RP and total group points. Such findings show that players’ RP was poorly related to the achievement of their teams in the UCL group stage, indicating trivial influence of RP on success in elite-level soccer.

Analysis of the Associations between Contextual Variables and Match Running Performance in Croatian First Division Soccer

It has been hypothesized that contextual variables (i.e. match location, opponents’ level) could be important deter- minants of running performance (RP) in soccer matches, but empirical studies provided inconsistent evidences. This study aimed to investigate the associations between contextual variables (CV) and RP in Croatian soccer players. Players’ RP (n=193) were evaluated, and used as cases in this study. CV included match outcome (win-draw-loss), opponent’s level (higher vs. lower ranked), and match location (home-away). RP were measured by global position- ing system during the soccer matches in seasons 2018/19 (n=14) and 2019/20 (n=15) of Croatian first division, and included: the total distance covered, low-intensity (&lt;14.3 km/h), running (14.4–19.7 km/h), high-intensity running (&gt;19.8 km/h), high-speed running (19.8–25.1 km/h) and sprinting (&gt;25.2 km/h). Results indicated significantly great- er amount of distance covered in running zone for away matches (F-test: 7.83, p&lt;0.01, small effect size; 1392±353 m and 1262±294 m, for home and away matches, respectively). Similar RP were observed irrespective of opponents’ level (F-test: 0.05 to 1.53, p&gt;0.05). Lowest total-, low- and running-zone distances were evidenced in won matches (9893±896 m, 8035±614 m and 1241±312 m, respectively), followed by drawn matches (10298±913 m, 8287±838 m and 1363±320 m, respectively) and lost matches (10355±1052 m, 8279±742 m and 1406±343 m, respectively). This study demonstrated that (i) won matches were characterized by lower RP, (ii) association between RP and match location was limited, (iii) RP was not related to the opponents’ level.

Effects of a competitive half-season on the aerobic capacity and match running performance of Turkish elite professional soccer players

This study examines how exertion during matches affects participants’ physical capacity and match performance. The study included 13 elite football league players (21 ± 0.7 years old; height, 181.1 ± 8.98 cm; body mass, 74.7 ± 8.1 kg) and used global positioning system (GPS) data collected during 12 official matches. Four matches after the first Yo-Yo IR1 test, four matches before the second Yo-Yo IR1 test, and four matches after the second Yo-Yo IR1 test are examined. Sprint count per minute (SC) (N/min), (&gt;19 km/h), p &lt; 0.030; distance covered at zone 4–6 per minute DCZ4 (km/h/min), (18–24 km/h), p &lt; 0.00; distance covered at zone 4–6 per minute DCZ5 (km/h/min), (24–30 km/h), p &lt; 0.001; and distance covered at zone 4–6 per minute DCZ6 (km/h/min), (30–39 km/h), p &lt; 0.001 were recorded. According to the values obtained before the tests, the match data show a decreasing trend in the following weeks. Furthermore, the relationship between physical performance values and tests is determined (average speed (AS) (km/h), r = 0.64; maximum speed (MS) (km/h), r = 0.50; DCZ4 (km/h/min), r = 0.89; DCZ5 (km/h), r = 0.81). As a result, time-dependent changes in intermittent endurance capacity during matches validated in-game running kinematics. This indicates the Yo-Yo IR1’s robustness as a fitness marker, and its capacity to help practitioners preview longitudinal variations in locomotor behavior during matches. Athletes who show a high degree of asymmetry in official matches seem to exhibit a strong ability to resist fatigue during testing.

Impact of Microcycle Structures on Physical and Technical Outcomes During Professional Rugby League Training and Matches

To assess the impact of microcycle (MC) structures on physical and technical performances in rugby league training and matches. Thirty-four professional rugby league players were monitored during all training sessions and matches across a single season wherein 2 different competition-phase MC structures were implemented. The first MC structure involved the first session on match day (MD) + 2 and the main stimulus delivered MD - 3, and the second structure delayed all sessions by 1day (first session on MD + 3 and main session MD - 2; MC structure in the second half of the season). Physical output was quantified via relative total speed (in meters per minute), high-speed running (per minute; ≥4.0m·s-1), and very-high-speed running (per minute; ≥5.5m·s-1), measured using a global positioning system (10Hz) in addition to accelerometer (100Hz) metrics (PlayerLoad per minute and PlayerLoadslow per minute]) during training and matches. Technical performance (number of runs, meters gained, tackles made and missed) was recorded during matches. Generalized linear mixed models and equivalence tests were used to identify the impact of MC structure on physical and technical output. Nonequivalent increases in meters per minute, high-speed running per minute, and PlayerLoad per minute were observed for the first training stimulus in MC structure in the second half of the season with no practical difference in midcycle sessions observed. The MC structure in the second half of the season structure resulted in increased high-speed running per minute and decreased PlayerLoadslow per minute during MD with no differences observed in technical performance. Delaying the first training stimulus of the MC allowed for greater training load accumulation without negative consequences in selected match running and technical performance measures. This increased MC load may support the maintenance of physical capacities across the in-season.

Influence of Repeated-Sprint Ability on the in-Game Activity Profiles of Semiprofessional Rugby Union Players According to Position

This study investigated the influence of repeated-sprint ability (RSA) on the activity of rugby union players in a competitive situation according to their position. Thirty-three semiprofessional rugby union players (age, 25.6 ± 4.3; height, 184.0 ± 8.0 cm; weight, 98.9 ± 13.9 kg, ~20 h training a week), divided into two position subgroups (forwards n = 20, backs n = 13) or four positional subgroups (front row and locks n = 13, back row n = 7, inside backs n = 6, outside backs n = 7), were tested. Their RSA was assessed with a 12 × 20 m sprint test over a 20 s cycle. GPS data (distance, acceleration, number of sprints, maximum velocity, and high-velocity running) and technical data were collected on 18 semiprofessional division rugby union games. In forwards, players with lower cumulated sprint time in the RSA test produced significantly more accelerations (ρ = −0.85, p < 0.001) and more combat actions per match minute (ρ = −0.69, p < 0.001). In backs, RSA was significantly correlated with high-intensity running [distance (ρ = −0.76), Vmax (ρ = −0.84), sprints frequency (ρ = −0.71), high-velocity running (ρ = −0.76), all p < 0.01]. Then, the players were divided into four subgroups (front row and locks, back row, inside backs and outside backs). RSA was significantly associated with the number of accelerations (ρ = −0.96, p <001) and combat actions in front row and locks (ρ = −0.71, p = 0.007). In the back row, RSA was correlated with distance (ρ = −0.96, p = 0.003) and the frequency of combat actions (ρ = −0.79, p = 0.04). In inside backs, RSA was significantly (all p < 0.01) correlated with distance (ρ = −0.81), number of accelerations (ρ = −0.94) and high-velocity running (ρ = −0.94), while in outside backs, RSA was associated with sprint frequency (ρ = −0.85) and the maximal in-game velocity reached (ρ = −0.89). These results demonstrate that RSA is associated with match running and combat activity performance (i) regardless of the position on the pitch and (ii) specifically for each player's position by improving the corresponding activity profile.