High-speed Distance Research Articles

Associations between Training Load and Well-Being in Elite Beach Soccer Players: A Case Report.

The current case study aimed to quantify within-subjects correlations between training load and well-being in elite male beach soccer players. Data were obtained over three consecutive days during the preparation camp for the FIFA Beach Soccer World Cup Russia 2021. The session rating of perceived exertion (s-RPE) and external training load metrics using global positioning system (GPS) were recorded. Eleven players reported perceived well-being (sleep quality, fatigue, muscle soreness and stress) using a Likert scale (Hooper Index) before breakfast. Within-subjects correlation coefficients between workload and well-being were calculated. Workload metrics and perceived well-being indices were significantly lower on day three than on days one and two. The Hooper Index presented a very large positive correlation with s-RPE (r = 0.86 [0.67, 0.94], 95% confidence interval, CI), exposure time (r = 0.88 [0.71, 0.95]), total distance (r = 0.83 [0.60, 0.93]), high-speed distance (r = 0.77 [0.50, 0.91]), and number of sprints (r = 0.75 [0.47, 0.90]). Sleep quality presented a moderate to large positive correlation with s-RPE (r = 0.51 [0.11, 0.77]), exposure time (r = 0.50 [0.10, 0.76]), high-speed distance (r = 0.53 [0.15, 0.78]), number of sprints (r = 0.62 [0.28, 0.83]) and total distance (r = 0.41 [0.18, 0.78]). Fatigue presented a large to very large positive correlation with s-RPE (r = 0.85 [0.66, 0.94]), exposure time (r = 0.90 [0.78, 0.96]), total distance (r = 0.86 [0.68, 0.94]), high-speed distance (r = 0.65 [0.31, 0.84]) and number of sprints (r = 0.56 [0.18, 0.79]). Muscle soreness presented a large to very large positive correlation with s-RPE (r = 0.79 [0.56, 0.91]), exposure time (r = 0.83 [0.62, 0.93]), total distance (r = 0.81 [0.59, 0.92]), high-speed distance (r = 0.75 [0.47, 0.89]) and number of sprints (r = 0.59 [0.22, 0.81]). Overall, workload presented a meaningful correlation with perceived well-being indices in elite male beach soccer players during a training camp. These findings suggest that workload metrics and perceived well-being indices can be implemented into the daily routine of an elite beach soccer team, which may assist coaches, sports scientists, and practitioners in better preparing players for beach soccer competitions.

The association between training load and physical development in professional male youth soccer players: a systematic review

Objectives 1) To evaluate current physical performance tests used within professional male youth soccer; 2) to understand the relationship of these tests performance in relation to specific measures of external and internal training load (TL) to conclude if there is a subsequent change in test performance. Methods Relevant literature was searched using five electronic databases (PubMed Medline, SPORTDiscus, Web of Science, CINAHL and Scopus), with additional articles identified by the authors. Articles relating to TL and physical development assessment within professional male youth soccer players were evaluated. Results Database searches yielded 5683 articles following removal of duplicates. After screening the titles, abstracts and full texts, 28 articles were identified. Both external TL (total distance, high speed distance, duration) and internal TL (rating of perceived exertion, training impulse) measures were found to be associated with improvements in physical test performance across both pre-season and in-season phases. Field-based testing was found to be sensitive to changes in physical performance for aerobic capacity, lower body power/strength and sprint performance. However, limited sensitivity to change was found when assessing player agility performance. Conclusion Future research in this area should look to enhance our understanding of the dose-response of TL with changes in fitness across different age groups in professional male youth soccer.

Paper 22: Increased Lower Extremity Injury Associated with Player Load and Distance in Collegiate Women’s Soccer

Objectives:High cumulative workloads and spikes in player workloads have been associated with an increased risk of injury in soccer and other sports. These studies, however, have all been conducted with data from male soccer players or male athletes in other sports, with few studies investigating female athletes. Using metrics collected from GPS units to monitor cumulative load and distance may be valuable for injury prevention. The purpose of this study was to examine the relationship between injury risk and workload as collected from wearable GPS units in NCAA Division I women’s soccer players.Methods:Lower extremity injury incidence and GPS workload data (player load, total distance, and high-speed distance) of 65 NCAA Division I women’s soccer players were collected over 3 seasons. Accumulated 1-, 2-, 3- and 4-weekly loads and acute: chronic workload ratios (ACWR) were classified into discrete ranges by z-scores. ACWR was calculated using rolling averages and exponentially weighted moving averages (EWMA) models. Binary logistic regression models were used to compare the 7:28 rolling average and EWMA ACWRs between injured and non-injured players for all GPS/accelerometer variables. The prior 1-, 2-, 3-, and 4-weekly accumulated loads for all GPS/accelerometer variables were compared between the injured and uninjured cohorts using two-sample t-tests with an alpha level of 0.05 set as significant.Results:There were a total of 53 lower extremity injuries that resulted in lost time recorded (5.76/1000 hours ‘on-field’ exposure time; 34 non-contact and 19 contact injuries). The prior 2-week (7,242 vs 6,613; p=0.02), 3-week (10,533 vs 9,718; p=0.02), and 4-week (13,819 vs 12,892; p=0.04) accumulated player loads and 2-week (62.40 vs 57.25 km; p=0.04), 3-week (90.97 vs 84.10 km; p=0.03), and 4-week (119.31 vs 111.38 km; p=0.05) accumulated total distances were significantly higher for injured players compared to non-injured players during the same timeframes. There were no significant differences in player load, total distance, or high-speed distance ACWR between injured and non-injured players for both the rolling averages and EWMA calculations.Conclusions:Higher accumulated player load and total distance, but not ACWR, are associated with injury in women’s soccer players.

Relationships Between Internal and External Load Measures and Fitness Level Changes in Professional Soccer Players

ABSTRACT Purpose: Understanding the dose-response relationship between internal and external training load with changes in aerobic fitness and intermittent running capacity, during different periods of the season, may help in optimizing training process. The aim of the present study was to investigate the dose-response relationships between load measures and changes in aerobic fitness and intermittent running capacity among a large cohort of professional soccer players. Methods: Training load, aerobic fitness and intermittent running capacity of 52 male adult professional players from 3 elite teams were monitored across an entire season and analyzed employing linear mixed models, with a significance level set at p≤0.05. Results: Relationships between load measures (training and match duration, sRPE-TL, total distance, high and very high-speed running distances) and changes in physical qualities were stronger during the preparation period (PREP) for both aerobic fitness (d= 0.48 to 0.76, p<0.031) and intermittent running capacity (d= 0.46 to 1.89, p<0.046). The magnitude of the relationships reduced during the first competitive period (d= 0.43 to 0.56) and the relationships became trivial in the second competitive period (d= 0.06 to 0.41, p= 0.063 to 0.846). Conclusion: The moderate to large relationships found between all measures of load and changes in physical capacities suggest that training prescription during the PREP was effective in improving players’ fitness. During the competitive phase small changes in aerobic and intermittent running capacities were found, highlighting that coaching staff pursue different aims during the competitive period, such as technical and tactical training and recovery.

Relationship between Physical Training and Tactical Training in Sports Training Relying on Boosting and Bagging Algorithms

With the development of sports, competition is becoming more and more confrontational and modern sports are developing in the direction of fast speed, fast rhythm, good skills, and high-altitude combat. And, this development requires good conditions and technology as a guarantee. Sports denote a competitive physical activity, which follows four aspects of competition: technology is the foundation, tactics are the means, the body is the cornerstone, and the psychology is the decisive point. Among these four factors, if the athlete does not have a good body, all techniques and know-how are empty talks. In this paper, two algorithms are introduced to track the athletes’ physical training and tactical training videos and the relevant data in the game are counted to obtain the physical indicators required by the athletes in each position. In a certain game, the sprint distance in the first round was 1979 m, the high-speed running distance was 2426 m, the high-intensity running distance was 4398 m, and the jogging distance was 1267 m.

The pre- and post-pitch-entry physical and technical responses of rugby league interchange players according to starting status

This study quantified the activities of interchange players during the 15 min before and 20 min after initial pitch-entry (INTentry) or re-entry (INTre−entry) for substitutes and starters, respectively, and identified relationships between pre- and post-pitch-entry responses. Fourteen semi-professional rugby league players wore Microelectromechanical Systems and were filmed throughout 10 matches in which they were interchanged (68 observations). Twelve physical and technical variables were analyzed for the pre-match warm-up, five, 10, and 15 min before INTentry or INTre−entry (physical variables only), and five min epochs following match-introduction. Linear mixed models indicated that during the 0–5 min following INTentry, physical and technical responses were typically greater (∼7.1% to 66.3%) than subsequent epochs while total (∼6.2%) and high-speed (37.1%) distance also exceeded the 0–5 min after INTre−entry (p &lt; 0.05). Edge forwards reached higher peak speeds (11.4% to 11.7%) than hookers and middle forwards, but hookers completed more passes (87.4% to 90.5%). Pre-pitch-entry movements were positively associated with post-pitch-entry tackles (r = 0.43 to 0.49) and high-speed distance (r = 0.46), but negatively associated with total distance (r = −0.32 to −0.68). Within tolerable limits, increasing the activity performed during the ∼15 min before pitch-entry could benefit high-speed match-play performance indicators. Transient changes in post-pitch-entry physical and technical responses could reflect self-pacing strategies, contextual factors, or perceived preparedness. The apparent absence of progressive performance-limiting fatigue, characterized by a plateau in responses after the initial five min following INTentry or INTre−entry, may suggest a role for interchange players to provide a more sustained impact and thus achieve interchange objectives.

Fast algorithm based on the Hilbert transform for high-speed absolute distance measurement using a frequency scanning interferometry method.

Frequency scanning interferometry using state-of-the-art high-speed frequency-swept laser source can be utilized to measure absolute distance on the order of micrometers to centimeters. Current distance demodulation methods based on fast Fourier transform (FFT) or fringe counting cannot achieve satisfactory accuracy when the number of sampling points within a frequency-sweeping period is small; the conventional Hilbert transform is more accurate, but it needs arctangent calculation and phase unwrapping, which is time consuming. So we propose a fast algorithm based on the conventional Hilbert transform to recover the distance from the interference signal. The algorithm is implemented by first performing a Hilbert transform and then solving the phase and the distance from the Hilbert signal with a novel, to the best of our knowledge, method that eliminates the need for arctangent calculation and phase unwrapping. The whole process took only 40 µs, and it is almost 2 times faster than the conventional Hilbert algorithm with little accuracy lost. Simulation results demonstrate that the proposed algorithm is more accurate than the FFT algorithm, and it achieved a standard deviation of 0.062 µm, which was less than that of the FFT, in our experiment at a distance of approximately 16 mm and measurement speed of 1 kHz.

Are acute:chronic workload ratios of perceived exertion and running based variables sensible to detect variations between player positions over the season? A soccer team study

BackgroundThe aim of this study was to describe and compare the in-season variations of acute: chronic workload ratio (ACWR) coupled, uncoupled, and exponentially weighted moving average (EWMA) through session rating of perceived exertion (s-RPE), total distance (TD), high-speed running distance (HSRD) and sprint distance (SPRINT) in three different periods of an elite soccer season according to player positions.MethodsTwenty male elite players (age: 29.4 ± 4.4) from an Asian First League team were daily monitored for twenty consecutive weeks during the 2017–2018 in-season. Forty-seven trainings and twenty matches were monitored using global positioning system units (GPS) to collect TD, HSRD and SPRINT. Through the collection of s-RPE, TD, HSRD, and SPRINT by ACWR and EWMA were calculated for each training session.ResultsThe results revealed that according to different periods of the season, workload measures observed in mid-season were meaningfully higher compared with early-season (g = ranging from 0.53 to 4.98) except for EWMASPRINT. In general, wingers and strikers tended to have greater scores in workload measures compared to the defenders and midfielders (g = ranging from 0.41 to 5.42).ConclusionsThese findings may provide detailed information for coaches and sports scientists regarding the variations of acute and chronic workload ratio and external loading in-season and between player positions in an elite soccer team.

External Match Load in Amateur Soccer: The Influence of Match Location and Championship Phase.

Assessment of the physical dimension implicit in the soccer match is crucial for the improvement and individualization of training load management. This study aims to: (a) describe the external match load at the amateur level, (b) analyze the differences between playing positions, (c) verify whether the home/away matches and if (d) the phase (first or second) of the championship influence the external load. Twenty amateur soccer players (21.5 ± 1.9 years) were monitored using the global positioning system. The external load was assessed in 23 matches, where 13 were part of the first phase of the competition (seven home and six away matches) and the other 10 matches belonged to the second (and final) phase of the championship (five home and five away matches). A total of 173 individual match observations were analyzed. The results showed significant differences between playing positions for all the external load measures (p < 0.001). There were higher values observed in the total distance covered for central defenders (p = 0.037; ES = 0.70) and in high-intensity decelerations for forwards (p = 0.022; ES = 1.77) in home matches than in away matches. There were higher values observed in the total distance (p = 0.026; ES = 0.76), relative distance (p = 0.016; ES = 0.85), and moderate-intensity accelerations (p = 0.008; ES = 0.93) for central defenders, in very high-speed running distance for forwards (p = 0.011; ES = 1.97), and in high-intensity accelerations (p = 0.036; ES = 0.89) and moderate-intensity decelerations (p = 0.006; ES = 1.11) for wide midfielders in the first phase than in the second phase of the championship. Match location and championship phase do not appear to be major contributing factors to influence the external load while the playing position should be used as the major reference for planning the external training load.

In-Season Quantification and Relationship of External and Internal Intensity, Sleep Quality, and Psychological or Physical Stressors of Semi-Professional Soccer Players.

Simple SummaryIn this study, we analyse the relationship of the in-season variations of external, internal and well-being measures across different periods of a semi-professional soccer season (early-, mid- and end-season) and describe TM and TS for the entire period of the analysis. The main findings of our study revealed that increasing the training intensity affects the well-being of the players and consequently the training intensity management. Coaches and their staff should consider the results of this study, because despite the relationship between external and internal intensity, each has a unique effect on the perception of the player’s training intensity management.The purpose of this study was two-fold: (a) to describe and analyse the relationship of the in-season variations of external and internal intensity metrics as well as well-being measures across different periods of a semi-professional soccer season (early-, mid- and end-season); and (b) to describe training monotony (TM) and training strain (TS) for 20 weeks in a semi-professional soccer season. Eighteen semi-professional players (age: 29 ± 4.1) from the Asian First League team participated in this study. The players were monitored for 20 consecutive weeks during in-season for external training intensity, internal training intensity and well-being parameters. The in-season was organized into three periods: early-season (weeks 1–7); mid-season (weeks 8–13); and end-season (weeks 14–20). Total distance (TD), high-speed running distance (HSRD), sprint distance, rate of perceived exertion (RPE), session-RPE (s-RPE), TM, TS, heart rate average and maximum, as well as sleep quality, stress and muscle soreness were collected. Results revealed that TD, HSRD and sprint distance (total values) were meaningfully greater during end-season than in the early-season. RPE showed a significantly highest value during the end-season (4.27 AU) than in early- (3.68 AU) and mid-season (3.65 AU), p < 0.01. TS showed significant differences between early-season with mid-season (p = 0.011) and end-season (p < 0.01), and the highest value occurred in week 17 during end-season (6656.51 AU), while the lowest value occurred in week 4 during early-season (797.17 AU). The average TD periods showed a moderate to large correlation with RPE, sleep and s-RPE at early-, mid- and end-season. Increasing the training intensity without considering the well-being of the players affects the performance of the team. Examining processes of the relationship between training intensity and other psychological indicators among players will probably be effective in training planning. Sports coaches and fitness professionals should be wary of changes in TM and TS that affect players performance. Therefore, to better control the training, more consideration should be given by the coaches.

Acute and Chronic Workload Ratios of Perceived Exertion, Global Positioning System, and Running-Based Variables Between Starters and Non-starters: A Male Professional Team Study

The study aim was 2-fold (i) to describe and compare the in-season variations of acute: chronic workload ratio (ACWR) coupled, ACWR uncoupled, and exponentially weighted moving average (EWMA) through session-rated perceived exertion (s-RPE), total distance (TD), high-speed running distance (HSRD), and sprint distance across different periods of a professional soccer season (early, mid, and end-season) between starters and non-starters; (ii) to analyze the relationship the aforementioned measures across different periods of the season for starters and non-starters. Twenty elite soccer players (mean ± SD age, 29.4 ± 4.4 y; height, 1.8 ± 0.1 m; and body mass, 74.8 ± 2.3 kg). They were divided into starter and non-starter groups and were evaluated for 20 weeks. ACWR had general changes throughout the season. At the beginning and end of the mid-season, the highest ACWR was observed in three parameters: s-RPE, TD, and HSRD. ACWR and EWMA through sprint distance were higher at the beginning of the early-season than at any other time of the season.The ACWR coupled of s-RPE shows a significant higher value for non-starters than starters (p = 0.015; g = −1.01 [−1.98, −0.09]) and the ACWR coupled of TD shows a significant higher value for starters than non-starters in early-season (p < 0.01; g = 3.01 [1.78, 4.46]) and shows a significant higher value for non-starters than starters in mid-season (p < 0.01; g = −2.52 [−3.83, −1.39]), and end-season (p < 0.01; g = −2.57 [−3.89, −1.43]). While the EWMA of TD shows a significant higher value for starters than non-starters in early-season (p < 0.01; g = 2.25 [1.17, 3.49]) and mid-season (p < 0.01; g = 2.42 [1.31, 3.71]), and shows a significant higher value for non-starters than starters in end-season (p < 0.01; g = −2.23 [−3.47, −1.16]). Additionally, we found some correlations between external and internal load measures during three periods of the in-season. The study’s main finding was that the indexes of ACWR and EWMA were useful to detect differences between period and between playing status with the exception for the sprint variable. In addition, the necessary work for non-starter players’ improvement is not done during training, and these players lose their readiness as the season progresses. Consequently, these players perform poorly during the match. Therefore, coaches and their staff should consider devising new activities to keep non-starter players physically fit. This deficit must be accounted for in training because they compete in fewer matches and have less burden than starters.

Acute caffeine supplementation and live match-play performance in team-sports: A systematic review (2000–2021)

ABSTRACT Caffeine is a psycho-active stimulant that can improve physical and cognitive performance. We systematically reviewed the evidence on the effects of acute caffeine ingestion on physiological parameters, physical and technical-skill performance during high-performance team-sport match-play. Following PRISMA guidelines, studies were identified using scientific databases (PubMed, Web-of-Science, Scopus, and SPORTDiscus) in February 2021. Of 281 results, 13 studies met inclusion, totalling 213 participants. Included studies adopted the randomised double-blinded cross-over design, involving caffeine and control conditions. In studies reporting physiological variables, responses to caffeine included higher peak (n=6/ 8 [n/ total studies measuring the variable]) and mean (n=7/ 9) heart rates, increased blood glucose (n=2/ 2) and lactate (n=2/ 2) concentrations. Improvements in physical performance were widely documented with caffeine, including greater distance coverage (n=7/ 7), high-speed distance coverage (n=5/ 7) and impact frequencies (n=6/ 8). From three studies that assessed technical-skills, it appears caffeine may benefit gross-skill performance, but have no effect, or negatively confound finer technical-skill outcomes. There is compelling evidence that ingesting moderate caffeine doses (~3 to 6 mg·kg−1) ~60 minutes before exercise may improve physical performance in team-sports, whereas evidence is presently too scarce to draw confident conclusions regarding sport-specific skill performance.

Training and Match Demands of Elite Rugby Union.

Cousins, BEW, Morris, JG, Sunderland, C, Bennett, AM, Shahtahmassebi, G, and Cooper, SB. Training and match demands of elite rugby union. J Strength Cond Res 37(1): 141-148, 2023-This study aimed to examine training and match demands associated with elite Rugby Union. Eighty-nine elite players were monitored using subjective (session ratings of perceived exertion) and objective (global positioning systems: distance and high-speed running [defined as >70% of individual maximum speed] distance) methods, alongside key performance indicator variables in matches (e.g., number of tackles made). These were compared between positions (forwards vs. backs) and league of competition (Premiership vs. Championship). Statistical significance was accepted as p < 0.05. Analysis revealed that backs covered greater distance (by 704 m, p < 0.001) in training and greater distance (by 7.6 m·min-1, p < 0.001) and high-speed running distance (by 1.22 m·min-1, p < 0.001) in matches, compared with forwards. In matches, the forwards experience greater key performance indicator demand (tackles: 78%; tackle assists: 207%; breakdown entries: 324%; contact events: 117%; all p < 0.001) compared with backs. The number of tackles (53%, p < 0.001) and tackles missed (35%, p = 0.001) were greater, whereas contact carries (12%, p = 0.010) and breakdown entries (10%, p = 0.024) were lower, in the Premiership compared with the Championship. Overall, these findings confirm that the running demands of Rugby Union are higher in backs, whereas contact actions are higher in forwards, with further differences between the Premiership and Championship. This comprehensive examination of the demands of elite Rugby Union could be used to ensure the specificity of training protocols for elite Rugby Union clubs, specific to both playing position (forward or back) and level of competition (Premiership or Championship).

The positional and temporal running demands of elite inter-county camogie match play across 5-min intervals.

PurposeCamogie is a native Irish female field sport game. This investigation aimed to establish elite camogie players’ positional and temporal running demands across 5-min intervals during competitive match play.MethodsThirty-one (n = 31) inter-county camogie players (age: 24 ± 4 years; height: 167.2 ± 6.3 cm; body mass: 67.0 ± 7.5 kg) from two squads wore commercially available 10-Hz Playertek GPS units (Playertek by Catapult, Australia) during Senior All-Ireland Championship games (n = 8). Players were categorised according to match positions (defenders, mid-fielders, forwards). Games were split into quarters, and subsequently into 5-min intervals for analysis (5-min intervals are more closely associated with small-sided games and training than half-by-half comparisons).ResultsAnalysis revealed significant positional and temporal differences to exist (p < 0.05). Mid-fielders covered greater total (r = 0.16–0.19) and relative distance (r = 0.15–0.17), with forwards covering greater high-speed distances (r = 0.09–0.19). Mid-fielders had greater temporal performance decrements for sprint distance between all first quarter intervals and 55–60 interval (Kendall’s W (W = 0.86–1.00), as well as the 0–5 and all final quarter intervals for total distance (W = 0.86–1.00). Defenders had significant performance decreases during the 25–30 (W = 0.29–0.60) and 40–45 interval (W = 0.14–0.57) for both total and relative distance. Forwards exhibited the lowest performance decrement, with no significant differences for peak speed, high-speed running, or sprint distance (W = 0.00–0.53).ConclusionPositional and temporal differences are evident in elite camogie match play. Mid-fielders have the greatest total and sprint distance decrements, with defenders also exhibiting total and relative distance decreases. Coaches should focus on temporal differences with respect to position, to minimise performance decrements.

The variability of physical match demands in elite women’s football

ABSTRACT Peak locomotor demands are considered as key metrics for conditioning drills prescription and training monitoring. However, research in female football has focused on absolute values when reporting match demands, leading to sparse information being provided regarding the degrees of variability of such metrics. Thus, the aims of this study were to investigate the sources of variability of match physical performance parameters in female football players and to provide a framework for the interpretation of meaningful changes between matches. 54 female players from four top-level clubs were monitored during one season. GPS APEX (STATSports, Northern Ireland), with a sampling frequency of 10 Hz, were used in 60 official matches (n = 393) to determine the full-match and 1-min peak locomotor demands of total distance (TD), high-speed running distance (HSRD), sprint distance (SpD), accelerations and decelerations (Acc/Dec) and peak speed (Pspeed). For each variable, the between-team, between-match, between-position, between-player, and within-player variability was estimated using linear mixed-effect modelling. With exception to SpD (29.4 vs. 31.9%), all other metrics presented a higher observed match-to-match variability in the 1-min peaks than in the full-match (6.5 vs. 4.6%; 18.7% vs. 15.9%; 12.9 vs. 11.7%; for TD, HSRD and Acc/Dec, respectively). With the exception of SpD, higher changes in 1-min peaks than in full-match values are required to identify meaningful changes in each variable. Different sources of variability seem to impact differently the match physical performance of female football players. Furthermore, to identify meaningful changes, higher changes in 1-min peaks than in full-match values are required.

Wearable Inertial Measurement Unit to Measure External Load: A Full-Season Study in Professional Soccer Players

The aim of this study was to describe weekly acute workload (wAW), chronic workload (wCW), acute: chronic workload ratio (wACWR), training monotony (wTM), and training strain (wTS) variations over a full season across playing positions. Twenty-one professional soccer players were daily monitored during 48 consecutive weeks. Total distance, sprint total distance (STD), high-speed running distance (HSRd), maximum speed, number of the repeated sprints, and body load (BL) were obtained during training and matches using a Wearable Inertial Measurement Unit. The wAW was determined for each external load measure. The wCW, wACWR, and wTM were calculated based on BL metric. Higher values of weekly STD were observed in lateral defenders/wingers (LDW) compared to central defenders/forwards (CDF) (p = 0.009; ES = Large) and midfielders (MDF) (p = 0.034; ES = Large). Additionally, weekly HSRd was higher in LDW vs. CDF (p = 0.016; ES = Large) and MDF (p = 0.011; ES = Large). The CDF presented a lower weekly number of repeated sprints than LDW (p = 0.021; ES = Large). In conclusion, weekly external load metrics were position-dependent over the season. Moreover, LDW a presented greater weekly STD, HSRd, and number of repeated sprints compared to other positions.

Utilizing the Maximum Workload Range for Practice Periodization

Commentary The maximum workload range (max range) is a concept suggested by Sanders et al.1 regarding a method used to prescribe adequate practice workloads based off wearable technology data. The max range is calculated as follows from game data: Max Range = (Mean Total Distance + 1 St. Dev.) to (Maximum Total Distance) While the example provided utilizes total distance, the max range can be applied to key performance indicators such as high-speed distance, training load, jumps, etc. that are tracked throughout the competitive season in team sports. The max range concept was developed from research that found 12-17% of the time, football athletes, depending on position, accumulated game workloads outside their position’s mean + 1SD. Anecdotally, many coaches and practitioners use simple game averages as a control for ideal practice volumes. Based on previous research, using the game average as control training threshold may result in some high performing athletes being under-conditioned. It is reasonable to suggest that potential compound effects may occur throughout an entire season if athletes are not engaging in rigorous training loads that mimic game-like volumes and intensities. Figure 1. Theoretical football periodization structure for a defensive back using the max range for high intensity training days.

Assessment of Peak Physical Demands in Elite Women Soccer Players: Can Contextual Variables Play a Role?

ABSTRACT Aim: To describe and compare the peak physical demands through the worst-case scenario method (WCS), according to different rolling average (RA) time epochs (i.e. 1 min, 3 min, and 5 min) and contextual variables in women soccer players. Methods: Using an observational-comparative study design, an elite women soccer team from the Spanish 1st league division was monitored during 27 matches. Nine WCS-dependent variables were assessed, including total distance (TD), high-speed running distance (HSR), sprint distance (SP), acceleration, and deceleration distance at different intensities by players position (i.e., central defenders [CD], wide defenders [WD], central midfielders [CM], wide midfielders [WM], forwards [F]), match half, location, and match outcome. Results: The 1-min RA showed the lowest variability (CV = 9.8–65.8%) for all nine dependent variables. The WD presented the highest TD (168 ± 15.71 m/min). Differences between positions were observed for: CM<F (−10.19 m/min), CM<WM (−11.20 m/min), and CM<WD (−12.70 m/min). For SP: CM<F (−10.03 m/min), CM<WM (−11.91 m/min), CM<WD (−10.03 m/min), and CM<CD (−5.31 m/min). The WCS-dependent variables were also affected by match half and match outcome. Conclusions: 1-min RA time epochs allow greater accuracy and reliability to identify nine key WCS outcomes in elite women soccer players. Different contextual variables, particularly player’s position, influenced the peak periods.

The reliability, validity and sensitivity of an individualised sub-maximal fitness test in elite rugby league athletes

ABSTRACT We aimed to examine the reliability, validity and sensitivity of an individualised sub-maximal fitness test (SMFTIFT60). Nineteen elite rugby league players performed a one-week test-retest of SMFTIFT60. Typical Errors and ICCs were: small (<3.5%) and extremely high (>0.90) for accelerometer-derived variables; moderate (<2.5% points) and moderate to very high (0.71–0.89) for exercise and recovery heart rate (HRex and HRR, respectively). Convergent validity correlations with the 10-week pre-season change in 30–15 Intermittent Fitness Test performance were large for changes in SMFTIFT60 HRex (r = −0.57) and HRR (0.60), and very large for changes in accelerometer measures (range: −0.71 to −0.79). For sensitivity, within-player dose–response relationships between SMFTIFT60 HRex and prior 3-day training loads were negative and ranged from moderate (session ratings of perceived exertion [sRPE-TL], r = −0.34), to large (high-speed running distance, −0.51; acceleration load, −0.73) and very large (heart rate Training Impulse [TRIMP], −0.83). All other relationships were unclear or trivial to small. Physiological and accelerometer-derived measures from the SMFTIFT60 are reliable and valid for the assessment of fitness in rugby league players. Only HRex appears sensitive to acute changes in training load. The SMFTIFT60 could be a useful monitoring tool in team sports

The influence of the field orientation on physical demands in soccer small-sided games

The aim of this study was to compare the physical demands of SSG with either greater length (SSGlength) or width (SSGwidth) with official soccer matches. Sixteen Brazilian U-20 national-level soccer players participated in two sessions with SSGlength (4v4, 40 m length and 26 m width) and two sessions with SSGwidth (4v4, 26 m length and 40 m width). External and internal load variables were monitored and compared to official games (12.8 ± 8.9 games per player). Data were standardized to the time and compared between the experimental conditions by a one-way analysis of variance (ANOVA) with repeated measures (level of significance set at p &lt; 0.05). The effect size was calculated by the partial ETA squared (ɳ p2). Results showed that the total distance covered during SSGlength was significantly higher compared to official matches (8.1%; p = 0.001) and SSGwidth (5.2%; p = 0.049). Highest values were registered in the matches when compared to SSGlength and SSGwidth for high-speed distance, sprint distance, maximal speed and number of sprints. The number of accelerations was significantly lower during official matches than SSGwidth (36.5%; p = 0.002) and SSGlength (45.0%; p &lt; 0.001). The number of high-speed actions was higher in official games when compared to SSGwidth (47.1%; p &lt; 0.001). No differences were found between matches and SSGlength ( p = 0.059). We concluded that the physical demands of the 4v4 SSGs adopted in this study were different from the physical demands of official match play. The use of a field with a greater width rather than length does not appear to make the physical demands of the SSG more similar to the official games.