Intra-Season Variations in Workload Parameters in Europe’s Elite Young Soccer Players: A Comparative Pilot Study between Starters and Non-starters

Background: The main purpose of the current study was to compare the within-season variations of workload, training duration, acute/chronic workload ratio (ACWR), training monotony ™, and training strain (TS) through session rating perceived exertion (s-RPE) between starters and non-starters. Methods: Seventeen under-17 European male soccer players (age, 16.2 ± 0.3 y, height, 1.8 ± 0.1 m; body mass, 66.5 ± 4.0 kg) divided in two groups: nine starters and eight non-starters, were evaluated over 50 weeks throughout the season. Results: In general, there were load variations for all players during the full-season. RPE tended to decrease during in-season and RPE, training duration and s-RPE did not present significant differences between starters and non-starters. TM and TS presented lower values for starters in mesocycle (M) 4 and M11 compared to non-starters. TS presented lower values for starters in M4 and M11 compared to non-starters, while in M10 a higher value was found for starters when compared to non-starters. ACWR showed differences between starters and non-starters in two of the mesocycles. Conclusions: This study showed that some mesocycles provided higher load for non-starters. This information can alert coaches that non-starter players are likely to try too hard in training to demonstrate their abilities, leading to non-functional overreaching, overtraining syndrome, and then poor performance.

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Influence of 2D:4D ratio on fitness parameters and accumulated training load in elite youth soccer players

BMC Sports Science Medicine and Rehabilitation ◽

10.1186/s13102-021-00354-5 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Hadi Nobari ◽

Ana Ruivo Alves ◽

Filipe Manuel Clemente ◽

Jorge Pérez-Gómez

Keyword(s):

Body Mass ◽

Muscular Strength ◽

Perceived Exertion ◽

Knee Extensor ◽

Training Load ◽

Soccer Players ◽

Youth Soccer ◽

Fitness Parameters ◽

Three Stages ◽

Left And Right

Abstract Background Digit ratio (2D:4D) characterized by the length of the second digit (2D) divided by the length of the fourth digit (4D), is a powerful marker of athletic performance. Some studies showed a negative correlation between 2D:4D ratio and sports performances. Objectives The purpose of the present study was three-fold: (1) to analyze the influence of anthropometric and 2D:4D ratio on variations of accumulated training load (ATL) and fitness parameters: maximal oxygen uptake (V̇O2max), countermovement jump (CMJ), isometric muscular strength of the knee extensor for hamstring (ISH) and flexor for quadriceps (ISQ) muscles; along three stages of evaluation of soccer players based on playing positions; (2) to analyze the correlations between 2D:4D ratio and aforementioned parameters; and (3) to investigate if variance in fitness levels and ATL can explain the 2D:4D ratio. Methods Twenty-four elite players under 17 years were daily monitored for their rating perceived exertion and ATL across 24 weeks over the season. Soccer players have also measured in three stages for anthropometric traits and fitness parameters. Results Significant differences were observed between playing positions for body mass, goalkeepers had higher body mass compared to centre-midfielder and winger players. Moreover, there were significant differences in ATL between early-season to mid-season in goalkeepers (P = 0.032). The 2D:4D ratio (left and right) shown largely and negatively association with muscular strength (ISQ: r = − 0.80; r = − 0.78, P ≤ 0.001, ISH: r = − 0.63; r = − 0.62, P = 0.001, respectively) and VO2max changes (r = − 0.55, P = 0.005; r = − 0.50, P = 0.013, respectively); lastly, both 2D:4D ratio significantly predicted changes in muscular strength and VO2max in young soccer players. Conclusions Goalkeepers tended to have higher body mass compared to centre-midfielder and winger players; and 2D:4D ratio revealed a mighty predictor of physical fitness changes in soccer players. Evidence should be helpful to professionals to highlight the usefulness of the 2D:4D into the identification of talent, but also to optimize young players' performance.

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Relationship between External and Internal Workloads in Elite Soccer Players: Comparison between Rate of Perceived Exertion and Training Load

Applied Sciences ◽

10.3390/app9235174 ◽

2019 ◽

Vol 9 (23) ◽

pp. 5174

Author(s):

Alessio Rossi ◽

Enrico Perri ◽

Luca Pappalardo ◽

Paolo Cintia ◽

F. Iaia

Keyword(s):

Perceived Exertion ◽

Selection Process ◽

Team Sports ◽

Training Load ◽

Soccer Players ◽

Gps Tracking ◽

Individual Response ◽

Rate Of Perceived Exertion ◽

The Relationship ◽

And Training

The use of machine learning (ML) in soccer allows for the management of a large amount of data deriving from the monitoring of sessions and matches. Although the rate of perceived exertion (RPE), training load (S-RPE), and global position system (GPS) are standard methodologies used in team sports to assess the internal and external workload; how the external workload affects RPE and S-RPE remains still unclear. This study explores the relationship between both RPE and S-RPE and the training workload through ML. Data were recorded from 22 elite soccer players, in 160 training sessions and 35 matches during the 2015/2016 season, by using GPS tracking technology. A feature selection process was applied to understand which workload features influence RPE and S-RPE the most. Our results show that the training workloads performed in the previous week have a strong effect on perceived exertion and training load. On the other hand, the analysis of our predictions shows higher accuracy for medium RPE and S-RPE values compared with the extremes. These results provide further evidence of the usefulness of ML as a support to athletic trainers and coaches in understanding the relationship between training load and individual-response in team sports.

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Variations of Workload Indices Prior to Injuries: A Study in Trail Runners

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17114037 ◽

2020 ◽

Vol 17 (11) ◽

pp. 4037 ◽

Cited By ~ 1

Author(s):

Sérgio Matos ◽

Filipe Manuel Clemente ◽

Rui Silva ◽

José María Cancela Carral

Keyword(s):

Body Mass ◽

External Load ◽

Injury Risk ◽

Perceived Exertion ◽

Training Time ◽

Positioning Systems ◽

Total Distance ◽

Injury Occurrence ◽

Global Positioning ◽

And Training

The purpose of this study was to compare the variations of weekly workload indices of internal and external load measures across the three weeks prior to injury occurrences in trail runners. Twenty-five trail runners (age: 36.23 ± 8.30 years old; body mass: 67.24 ± 5.97 kg; height: 172.12 ± 5.12 cm) were monitored daily for 52 weeks using global positioning systems (GPSs) to determine the total distance covered. Additionally, a rate of perceived exertion (RPE) scale was applied to determine session-RPE (sRPE: RPE multiplied by training time). The accumulated load (AL), acute: chronic workload ratio (ACWR), training monotony (TM), and training strain (TS) indices were calculated weekly for each runner. During the period of analysis, the injury occurrences were recorded. The differences were observed in AL and ACWR for sRPE and training time were significantly greater during the injury week when compared to the previous weeks. Similar evidence was found in TM and TS indices for sRPE, training time, and total distance. Furthermore, no meaningful differences were observed in AL and ACWR for total distance in the weeks prior to injury occurrence. Nevertheless, significant between-subjects variability was found, and this should be carefully considered. For that reason, an individualized analysis of the workload dynamics is recommended, avoiding greater spikes in load by aiming to keep a progressive increment of load without consequences for injury risk.

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Performance and Training Load Profiles in Recreational Male Trail Runners: Analyzing Their Interactions during Competitions

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17238902 ◽

2020 ◽

Vol 17 (23) ◽

pp. 8902

Author(s):

Sérgio Matos ◽

Filipe Manuel Clemente ◽

Rui Silva ◽

Joel Pereira ◽

José María Cancela Carral

Keyword(s):

Perceived Exertion ◽

Training Load ◽

Load Variations ◽

Rate Of Perceived Exertion ◽

Large Correlation ◽

Load Rate ◽

Maximal Aerobic Speed ◽

Meaningful Relationships ◽

Trail Running ◽

And Training

Endurance sports like trail running constitute an extensive individual modality causing numerous physiological changes to occur in the athlete. In this sense, an adequate monitoring of training load appears to be essential to improve competition performance. The aim of this study was two-fold: (i) to analyze trail runners’ weekly load variations in the four weeks leading up to a trail running competition, and (ii) to determine the relationship between the runners’ pacing in competitions and their physical fitness and workload parameters. Twenty-five amateur male trail runners (age: 36.23 ± 8.30 years old; minimum International Trail Running Association performance index: 600) were monitored daily for the duration of a season (52 weeks). External load (distance covered, pace) and internal load (rate of perceived exertion) were measured daily. Additionally, weekly workload measures of acute:chronic workload ratio (ACWR), training monotony, and training strain were calculated. The runners were also assessed for maximal aerobic speed (MAS) every four months. No significant differences in workload measures (p > 0.05) were observed in the four weeks leading up to each short trail competition; however, leading up to the long trail, ultra-trail medium, and ultra-trail long/extra-long competitions, the differences in the runners’ workload measures were significant (p < 0.05). In the short trail, pace was found to be moderately correlated with the ACWR of total distance (r = −0.334) and with training monotony of rate of perceived exertion (RPE) (r = −0.303). In the ultra-trail, a large correlation was observed between pace and elevation accumulated (r = 0.677). We concluded that significant workload differences from one week to the next only occurred in preparation for longer-distance competitions, with sudden acute load decreases and very low ACWR values reported mainly in weeks 1 and 2 of the taper. Meaningful relationships were found between performance (pace) and MAS for longer trails and between pace and MAS for ultra-trail competitions.

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Associations between Physical Status and Training Load in Women Soccer Players

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph181910015 ◽

2021 ◽

Vol 18 (19) ◽

pp. 10015

Author(s):

Lillian Gonçalves ◽

Filipe Manuel Clemente ◽

Joel Ignacio Barrera ◽

Hugo Sarmento ◽

Gibson Moreira Praça ◽

...

Keyword(s):

Perceived Exertion ◽

Vertical Jump ◽

Training Load ◽

Rating Of Perceived Exertion ◽

Soccer Players ◽

Load Range ◽

Change Of Direction ◽

Fitness Assessment ◽

Cohort Design ◽

And Training

This study aimed to analyze the variations of fitness status, as well as test the relationships between accumulated training load and fitness changes in women soccer players. This study followed an observational analytic cohort design. Observations were conducted over 23 consecutive weeks (from the preseason to the midseason). Twenty-two women soccer players from the same first Portuguese league team (22.7 ± 5.21 years old) took part in the study. The fitness assessment included anthropometry, hip adductor and abductor strength, vertical jump, change of direction, linear speed, repeated sprint ability, and the Yo-Yo intermittent recovery test. The training load was monitored daily using session rating of perceived exertion (s-RPE). A one-way repeated ANOVA revealed no significant differences for any of the variables analyzed across the three moments of fitness assessments (p > 0.05). The t-test also revealed no differences in the training load across the moments of the season (t = 1.216; p = 0.235). No significant correlations were found between fitness levels and accumulated training load (range: r = 0.023 to −0.447; p > 0.05). This study revealed no differences in the fitness status during the analyzed season, and the fitness status had no significant relationship with accumulated training load.

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Weekly Load Variations of Distance-Based Variables in Professional Soccer Players: A Full-Season Study

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17093300 ◽

2020 ◽

Vol 17 (9) ◽

pp. 3300 ◽

Cited By ~ 3

Author(s):

Filipe Manuel Clemente ◽

Rui Silva ◽

Daniel Castillo ◽

Asier Los Arcos ◽

Bruno Mendes ◽

...

Keyword(s):

Standard Deviation ◽

High Speed ◽

Training Load ◽

Effect Sizes ◽

Soccer Players ◽

Load Variations ◽

Total Distance ◽

Professional Soccer ◽

Moderate Effect ◽

And Training

The aim of this study was two-fold: (1) to analyze the variations of acute load, training monotony, and training strain among early (pre-season), mid (first half of season), and end season (second half of season) periods; (2) to compare these training indicators for playing positions in different moments of the season. Nineteen professional players (age: 26.5 ± 4.3 years; experience as professional: 7.5 ± 4.3 years) from a European First League team participated in this study. The players were monitored daily over a 45-week period for the total distance (TD), distance covered (DC) at 14 km/h−1 or above (DC > 14 km/h), high-speed running above 19.8 km/h−1 (HSR) distance, and number of sprints above 25.2 km/h−1. The acute load (sum of load during a week), training monotony (mean of training load during the seven days of the week divided by the standard deviation of the training load of the seven days), and training strain (sum of the training load for all training sessions and matches during a week multiplied by training monotony) workload indices were calculated weekly for each measure and per player. Results revealed that training monotony and training strain for HSR were meaningfully greater in pre-season than in the first half of the in-season (p ≤ 0.001; d = 0.883 and p ≤ 0.001; d = 0.712, respectively) and greater than the second half of the in-season (p ≤ 0.001; d = 0.718 and p ≤ 0.001; d = 0.717). The training monotony for the sprints was meaningfully greater in pre-season than in the first half of in-season (p < 0.001; d = 0.953) and greater than the second half of in-season (p ≤ 0.001; d = 0.916). Comparisons between playing positions revealed that small-to-moderate effect sizes differences mainly for the number of sprints in acute load, training monotony, and training strain. In conclusion, the study revealed that greater acute load, training monotony, and training strain occurred in the pre-season and progressively decreased across the season. Moreover, external defenders and wingers were subjected to meaningfully greater acute load and training strain for HSR and number of sprints during the season compared to the remaining positions.

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Curve Sprint in Elite Female Soccer Players: Relationship with Linear Sprint and Jump Performance

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18052306 ◽

2021 ◽

Vol 18 (5) ◽

pp. 2306

Author(s):

Ronaldo Kobal ◽

Tomás T. Freitas ◽

Alberto Fílter ◽

Bernardo Requena ◽

Renato Barroso ◽

...

Keyword(s):

Body Mass ◽

Soccer Players ◽

Training Methods ◽

Jump Performance ◽

Significance Level ◽

Change Of Direction ◽

And Training

The aim of this study was to examine the associations between linear sprint, curve sprint (CS), change of direction (COD) speed, and jump performance in a sample of 17 professional female soccer players. All athletes performed squat and countermovement jumps, single leg horizontal triple jumps, 17 m linear sprints, CS tests, and a 17 m Zigzag COD test. A Pearson product–moment test was performed to determine the relationships among the assessed variables. The significance level was set at p < 0.05. Nearly perfect associations (r > 0.9) were found between linear and CS velocities. Players faster in linear sprints and CS exhibited greater COD deficits. No significant associations were found between COD deficit and either body mass or sprint momentum. Jumping ability was significantly correlated with linear sprint and CS performance, but not to COD performance. These findings may be used by coaches and practitioners to guide testing and training prescriptions in this population. The associations observed here suggest that training methods designed to improve linear sprint and CS velocities may benefit from the implementation of vertically and horizontally oriented plyometric exercises.

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An Approach to the Fatigue in Young Soccer Players Resulting from Sided Games

Sports ◽

10.3390/sports7070174 ◽

2019 ◽

Vol 7 (7) ◽

pp. 174

Author(s):

Daniel Castillo ◽

Javier Yanci ◽

Silvia Sánchez-Díaz ◽

Javier Raya-González

Keyword(s):

Body Mass ◽

Perceived Exertion ◽

Total Duration ◽

Rating Of Perceived Exertion ◽

Soccer Players ◽

Training Context ◽

Internal Load ◽

Bout Duration ◽

Before And After ◽

Age Category

It is crucial to understand the fatigue associated with sided games (SGs) of soccer in the training context, in order to establish the appropriate intervals between training sessions. Thus, the aim of this study was to investigate the effects of different SGs on internal load, measured by the session rating of perceived exertion (sRPE), and on sprint performance. Ten outfield players (age: 14.5 ± 0.5 years, height: 169 ± 6 cm, body mass: 59.7 ± 6.4 kg) belonging to U15 age category participated in this study. The participants played four SG formats with modifications in the pitch size and in the bout duration, but with the same total duration for the SGs (SG1, SG2, SG3, and SG4). All the players performed a 10 and a 30 m sprint test before and after the SGs. The internal load was measured by the sRPE. The results showed no significant differences (p > 0.05) in the sRPE registered by the soccer players for the different SGs, but worse sprint performances over the 10 m (p < 0.05; ES: 0.74–1.38, large) and 30 m (p < 0.05; ES: 0.70–2.10, moderate to large) distances after completion of the SGs, except the 10 m sprint after SG2 and SG3 (p > 0.05; ES: 0.43–0.55, moderate). In addition, no correlation (p > 0.05) was reported between the sprint performances for the 10 and 30 m distances and the sRPE registered during the SGs. These results could be useful for technical staff wishing to design the playing area and bout duration of their training tasks effectively.

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Variations of Training Workload in Micro- and Meso-Cycles Based on Position in Elite Young Soccer Players: A Competition Season Study

Frontiers in Physiology ◽

10.3389/fphys.2021.668145 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hadi Nobari ◽

Reyhaneh Vahabidelshad ◽

Jorge Pérez-Gómez ◽

Luca Paolo Ardigò

Keyword(s):

Perceived Exertion ◽

Training Programs ◽

The Other ◽

Rating Of Perceived Exertion ◽

Soccer Players ◽

Daily Monitoring ◽

Good Guide ◽

Soccer Team ◽

And Training ◽

Field Position

The objectives of this study were to quantify the matches and training workload in micro-cycles of an elite young soccer team considering field position and to explain meso-cycles based on change of weekly acute (wAWL), chronic load (wCWL), acute-to-chronic workload ratio, training monotony (wTM), and training strain (wTS) between early-, mid-, and end-season periods considering playing position and whole team. Twenty-six under-16 elite young soccer players participated in this study, including six wide defenders and wide midfielders (WM), five central defenders (CD) and central midfielders, and four strikers (ST). Daily monitoring was performed by players for 20 weeks with the rating of perceived exertion using the Borg CR-10 scale. In comparison with early-season, results showed that there was a significant increase, in all playing positions, in wAWL and wCWL (except ST) and in wTM (except CD and ST) compared with end-season. On the other hand, there were significant reductions in wTS in CD, WM, and ST at the end-season. According to the results, coaches should consider the field position in different situations. Differences between training workload and matches can be a good guide for coaches, who have a special understanding of what causes the most load in training programs. Excessive training workload can potentially cause injury to adolescent athletes and controlling wTM can prevent this.

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Blood Biomarkers Variations across the Pre-Season and Interactions with Training Load: A Study in Professional Soccer Players

Journal of Clinical Medicine ◽

10.3390/jcm10235576 ◽

2021 ◽

Vol 10 (23) ◽

pp. 5576

Author(s):

Filipe Manuel Clemente ◽

Francisco Tomás González-Fernández ◽

Halil Ibrahim Ceylan ◽

Rui Silva ◽

Saeid Younesi ◽

...

Keyword(s):

Injury Risk ◽

Perceived Exertion ◽

Hematological Parameters ◽

Blood Parameters ◽

Training Load ◽

Soccer Players ◽

Immune Functions ◽

Professional Soccer ◽

Biochemical Analyses ◽

And Training

Background: Pre-season training in soccer can induce changes in biological markers in the circulation. However, relationships between chosen hematological and biochemical blood parameters and training load have not been measured. Objective: Analyze the blood measures changes and their relationships with training loads changes after pre-season training. Methodology: Twenty-five professional soccer players were assessed by training load measures (derived from rate of perceived exertion- known as RPE) during the pre-season period. Additionally, blood samples were collected for hematological and biochemical analyses. Results: For hematological parameters, significant increases were found for platelets (PLT) (dif: 6.42; p = 0.006; d = −0.36), while significant decreases were found for absolute neutrophils count (ANC) (dif: −3.98; p = 0.006; d = 0.11), and absolute monocytes count (AMC) (dif: −16.98; p = 0.001; d = 0.78) after the pre-season period. For biochemical parameters, there were significant increases in creatinine (dif: 5.15; p = 0.001; d = −0.46), alkaline phosphatase (ALP) (dif: 12.55; p = 0.001; d = −0.84), C-reactive protein (CRP) (dif: 15.15; p = 0.001; d = −0.67), cortisol (dif: 2.85; p = 0.001; d = −0.28), and testosterone (dif: 5.38; p = 0.001; d = −0.52), whereas there were significant decreases in calcium (dif: −1.31; p = 0.007; d =0.49) and calcium corrected (dif: −2.18; p = 0.015; d = 0.82) after the pre-season period. Moreover, the Hooper Index (dif: 13.22; p = 0.01; d = 0.78), and all derived RPE measures increased after pre-season period. Moderate-to-very large positive and negative correlations (r range: 0.50–0.73) were found between the training load and hematological measures percentage of changes. Moderate-to-large positive and negative correlations (r range: 0.50–0.60) were found between training load and biochemical measures percentage of changes. Conclusions: The results indicated heavy physical loads during the pre-season, leading to a decrease in immune functions. Given the significant relationships between blood and training load measures, monitoring hematological and biochemical measures allow coaches to minimize injury risk, overreaching, and overtraining.

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