The influence of youth soccer players' sprint performance on the different sided games' external load using GPS devices

Do Different Playing Formats and Aerobic Capacity Influence Variances in Psychophysiological Demands and Technical Performance in Small-Sided Games? A Study among Under-17 Male Soccer Players

This study aimed to: (i) analyze the variations in psychophysiological demands (mean heart rate, meanHR; rate of perceived exertion, RPE) and technical performance (umber of successful and unsuccessful passes, and occurrences of ball loss) between 2v2 and 4v4 small-sided games (SSGs) formats, and (ii) examine the relationships of aerobic capacity measured in Yo-Yo Intermittent Recovery Test (YYIRT) on psychophysiological and technical performance during SSGs. This study used a cross-sectional design with repeated measures, where the same players participated in both 2v2 and 4v4 formats across two training sessions per format. Twenty-four talent/developmental male youth soccer players, aged 16.6 ± 0.5 years. The meanHR, measured through heart rate sensors, the RPE, assessed using the CR6-20 scale, and the number of successful and unsuccessful passes, along with occurrences of ball loss, recorded using an ad hoc observational tool, were evaluated in each repetition. Players during the 2v2 format had significantly greater mean HR (+4.1%; p < 0.001; d = 2.258), RPE (+12.2%; p < 0.001; d = 2.258), successful passes (+22.2%; p = 0.006; d = 0.884), unsuccessful passes (+62.5%; p < 0.001; d = 1.197) and lost balls (+111.1%; p < 0.001; d = 2.085) than 4v4 format. The YYIRT was significantly and largely correlated with unsuccessful passes (r = 0.502; p = 0.012) and lost balls (r = 0.421; p = 0.041) in 2v2 format. In conclusion, this study suggests that engaging in 2v2 activities constitutes a more intense form of practice, significantly enhancing individual participation in technical aspects. Moreover, aerobic capacity may influence the smaller formats of play and how players perform key technical actions. Therefore, coaches must consider this to ensure the necessary performance in such games.

Maximum Strength and Power as Determinants of Match Skating Performance in Elite Youth Ice Hockey Players

ABSTRACT

Keiner, M, Kierot, M, Stendahl, M, Brauner, T, and Suchomel, TJ. Maximum strength and power as determinants of match skating performance in elite youth ice hockey players. J Strength Cond Res 38(6): 1090-1094, 2024-Maximum strength has a strong influence on speed-strength performances such as sprints and jumps. Important for sports practice is whether these findings are also reflected in game performance. Therefore, the aim of this study was to explore the influence of maximum strength and power performance on linear on-ice skating performance in testing and during game play. A cross-sectional study was conducted, and 24 highly trained male youth ice hockey players participated. Jump performances (countermovement jump [CMJ], drop jumps), maximum strength (1 repetition maximum [1RM] squat and isometric trap bar pull [ITBP]), and on-ice linear sprints (15 m [LS15], 30 m [LS30], flying 15 m [FLY15]) were measured. Match performances (among others: peak skating speed) were collected of 4 regular league games using a local positioning system. Correlation coefficient and explained variance were calculated ( ρ ≤ 0.05). Correlations between maximum strength and jump with on-ice linear sprint performance showed 1-35% explained variance. Correlations between "off ice" test (CMJ, relative 1RM) and game data (peak skating speed) showed 22-30% explained variance, respectively, while ITBP and DJ missed significant level. Between linear sprint and game performance showed 15-59% explained variance. In this study, a clear influence of 1RM in squatting and CMJ performance on on-ice linear sprint as well as in-game peak skating speed was observed. These findings show that strength and jumping performance can be valuable tests within a comprehensive test battery and indicate the relevance of strength and jumping tasks within the regular exercise program to improve in-game skating performance.

Physiological and locomotor variations of 3v3 and 5v5 small-sided games soccer formats: A 4-month study on sedentary young adults

The objectives of this study were twofold: (a) to analyze the variability of 3v3 and 5v5 small-sided games (SSG) formats in sedentary young adults, and (b) to compare the physiological and locomotor demands of 3v3 and 5v5 SSG formats while considering variations based on sex. The study followed a longitudinal design over 4 months. Thirty sedentary young adults with a mean age of 20.2 ± 1.0 years, height of 1.67 ± 0.06 m, and body mass of 86.3 ± 11.8 kg were included in the study. The participants engaged in 3v3 and 5v5 SSG formats, with each format being played 10 times per month. During each session, heart rate (HR), rate of perceived exertion (RPE), and total distance were measured and analyzed. The within-player variability for HR ranged from a minimum of 1.6% to a maximum of 2.8% (considering the levels at each month), while the between-players variability for HR ranged from a minimum of 1.4% to a maximum of 2.6% (considering the levels at each month). Similar variability patterns were observed for the other outcomes. In terms of comparisons between the formats, the 3v3 format resulted in higher RPE than the 5v5 format for both male (p = 0.006) and female (p = 0.628) participants, as well as for the other outcome measures. In summary, these findings highlight the reproducibility of physiological responses in 3v3 and 5v5 SSG among sedentary individuals. Notably, the 3v3 format consistently induced higher RPE levels. These findings underscore the importance of programming SSG based on sex and format preferences for optimizing exercise outcomes in sedentary.

Physical demands in a small-sided soccer game: a comparison between arbitrary and individualized speed and metabolic power thresholds

BACKGROUND

This study compared the arbitrary and individualized speed and metabolic power (Pmet) intensity thresholds in a small-sided game (SSG) regarding: 1) distance covered; 2) variations of the physical parameters during the SSG; and 3) associations with physical fitness.

METHODS

Twenty-four amateur soccer players (age: 20.0±1.7 years; height: 176.4±4.2 cm; body mass: 67.6±3.2 kg), after being tested for maximal aerobic speed (MAS) and maximal sprinting speed (MSS), participated in a SSG in a separate session and were monitored with global positioning systems (GPS). The distance covered was classified into three intensity zones for each variable (speed and Pmet) using arbitrary and individualized zones based on MAS.

RESULTS

There were differences in the distance covered between methods in zones 1 and 2 for both speed and Pmet (P<0.001), and in zone 3 only for Pmet (P<0.001). There were no variations in any variable analyzed during the SSG. MAS was positively correlated with the distance covered in zone 3 in the arbitrary speed (r=0.67; P<0.001) and Pmet (r=0.60; P<0.01). MSS was negatively correlated with the distance covered in zone 3 in the individualized speed (r=-0.49; P<0.05) and Pmet (r=-0.48; P<0.05).

CONCLUSIONS

This study showed that arbitrary and individualized provide different information. While the individualized method could be used to monitor physical demands, the arbitrary could be used to assess running physical performance.

Short-Term Effects of Lower-Extremity Heavy Resistance versus High-Impact Plyometric Training on Neuromuscular Functional Performance of Professional Soccer Players

BACKGROUND

To compare the effects of short-term 8 week heavy-resistance or plyometric training protocols (HRT or PLY) incorporated into regular soccer practice on measures of neuromuscular functional performance in professional soccer players, a single-blind randomized controlled trial was conducted.

METHODS

Forty-seven participants aged 22.3 ± 3.52 years were assigned to three groups: HRT (n = 15), PLY (n = 15), and control (CON; n = 17). The HRT group performed 3 sets and 10 repetitions twice a week using 80% of their baseline 1-RM (weeks 1-3), followed by 8 repetitions at 85% 1-RM (weeks 4-6), and 6 repetitions at 90% 1-RM (weeks 7-8) of 6 lower-body strength exercises with a 1 min rest period between sets. The PLY protocol involved a preparatory phase (weeks 1-2), followed by two 3-week progressive periods (weeks 3-5 and weeks 6-8). The plyometric sessions consisted of four jump exercises/drills with progressively increasing number of sets and total number of foot contacts. The rest intervals between repetitions and sets were 15 and 90 s, respectively. Outcome measures included tests assessing 10 and 30 m speed (t10m and t30m), one-repetition maximum half-back squat (1-RM squat), isokinetic peak torques for the quadriceps and hamstring muscles (Qcon and Hcon), countermovement jump (CMJ), and squat jump (SJ).

RESULTS

Two-way ANOVA detected main effects of time and group×time interactions for all examined variables, except t30m, 1-RM, and relative 1-RM. Post hoc analyses revealed significant increases in the HRT group (t10m: 6.3%, t30m: 7.1%; absolute 1-RM: 29.6%; relative 1-RM: 30.3%, Qcon: 24.5%; Hcon: 14.4%; CMJ: 5.9%; SJ: 7.2%, all p < 0.001) and the PLY group (t10m: 3.1%; t30m: 4.1%; absolute 1-RM:19.1%; relative 1-RM: 20.3%; Qcon: 12.6%; Hcon: 8.7%; CMJ: 3.3%; SJ: 3.5%, all p < 0.001). HRT was superior compared to PLY in relative 1-RM, Qcon and Hcon (all p < 0.001). In addition, we found knee muscular strength imbalance in 70.5% of participants from the total sample (H/Q ratio < 60%). The HRT and PLY protocols resulted in improved neuromuscular functional performance compared to the regular soccer regime.

CONCLUSIONS

This study showed that during the pre-competitive season, additional HRT and PLY drills/exercises as a substitute for standard soccer training as part of a regular 90 min practice twice a week for 8 weeks, can produce acute physical performance-enhancing effects in professional soccer players.

Validity and reliability of Polar M400 GPS watches for measuring distances covered by team sports players

Monitoring locomotor demands in team sports becomes popular in professional and recreational daily activities. Precise measurements are main of importance in training routine. The aim of this study is three-fold: (i) analyze the validity of Polar M400 Global Positioning System (GPS) watches for measuring distances covered in team sports simulation cycle; (ii) testing inter-unit reliability of two devices attached during testing; and (iii) testing inter-session reliability for the same simulation cycle. Methods: Twenty-one team athletes (age: 24.5 ± 5.2 years; body mass: 71.8 ± 5.7 kg; height: 176.5 ± 4.3 cm) were tested in the team sport simulation cycle (TSSC). Two Polar M400 sport watches were used by each player on their wrists at the same time. The data obtained from Polar M400 were compared to the reference fixed distance of the TSSC to determine the watch validity. Inter-session reliability was also tested using the two watches in two different sessions. Results: No significant differences between the reference value and the watches (F = 1.086; p = 0.368; η p 2 ≤0.042) were found. The %CV (0.03-0.05%) and SEM (0.05-0.09) values found for all considered groups confirmed good levels of reliability of the Polar M400 to measure total distance. Conclusions: The Polar M400 is a valid and reliable watch for measuring the distances covered by team sport athletes. Both coaches and athletes can monitor the distances covered with accuracy and precision, through the use of the Polar M400 sport watch.

Resultant equations for training load monitoring during a standard microcycle in sub-elite youth football: a principal components approach

Applying data-reduction techniques to extract meaningful information from electronic performance and tracking systems (EPTS) has become a hot topic in football training load (TL) monitoring. The aim of this study was to reduce the dimensionality of the internal and external load measures, by a principal component approach, to describe and explain the resultant equations for TL monitoring during a standard in-season microcycle in sub-elite youth football. Additionally, it is intended to identify the most representative measure for each principal component. A principal component analysis (PCA) was conducted with a Monte Carlo parallel analysis and VariMax rotation to extract baseline characteristics, external TL, heart rate (HR)-based measures and perceived exertion. Training data were collected from sixty sub-elite young football players during a 6-week training period using 18 Hz global positioning system (GPS) with inertial sensors, 1 Hz short-range telemetry system, total quality recovery (TQR) and rating of perceived exertion (RPE). Five principal components accounted for 68.7% of the total variance explained in the training data. Resultant equations from PCA was subdivided into: (1) explosiveness, accelerations and impacts (27.4%); (2) high-speed running (16.2%); (3) HR-based measures (10.0%); (4) baseline characteristics (8.3%); and (5) average running velocity (6.7%). Considering the highest factor in each principal component, decelerations (PCA 1), sprint distance (PCA 2), average HR (PCA 3), chronological age (PCA 4) and maximal speed (PCA 5) are the conditional dimension to be considered in TL monitoring during a standard microcycle in sub-elite youth football players. Current research provides the first composite equations to extract the most representative components during a standard in-season microcycle in sub-elite youth football players. Futures research should expand the resultant equations within training days, by considering other well-being measures, technical-tactical skills and match-related contextual factors.

The effects of different small-sided games configurations on heart rate, rating of perceived exertion, and running demands in professional soccer players

We examined the effects of different small-sided games (SSG) configurations on heart rate (HR), rating of perceived exertion (RPE), and running demands in soccer players. Twelve male soccer players (U18) participated in this randomized cross-over study. Players performed three SSG in different "fixed" and "dynamic" pitch sizes (3v3 in large (SSGL) and small (SSGS) fixed area; or 3v3 in dynamic dimensions [SSGD]), with 4x4 minutes interspersed by 2 minutes of rest. HR measures (maximum [HRmax], average [HRavg], and percentage of maximum [%HRmax]), RPE, and running demands were collected across the SGG sessions. The following running activities were recorded: total distance covered (TD), distance covered (DC) at 6-12 km·h-1, ≥ 12-18 km·h-1, and >18 km·h-1, peak running speed, acceleration (ACC) and deceleration (DEC) at 1-2 m·s-2 and 2-3 m·s-2, player load, and high metabolic load distance (HMLD). SSGL displayed higher HRavg, %HRmax, and RPE values than SSGS (p < 0.05). SSGL resulted in higher TD, DC at 6-12 km·h-1, ≥ 12-18 km·h-1, > 18 km·h-1, and higher peak speed than SSGS and SSGD (p < 0.05). Moreover, SSGD presented higher TD and DC at 6-12 km·h-1 and ≥ 12-18 km·h-1 than SSGS (p < 0.05). In contrast, SSGD and SSGS showed higher number of ACC and DEC at 1-2 m·s-2 than SSGL (p < 0.05). In conclusion, the pitch size and playing area of the SSG can be manipulated to promote desired physiological and physical demands in young soccer players.HighlightsWe examined how fixed (small and large) or variable (dynamic) pitch sizes affected the psychophysiological and running demands of young soccer players during small-sided games.Small-sided games with larger pitch sizes and areas per player elicited greater psychophysiological and running demands than small areas.The pitch size designed in the current study does not appear to affect the number of acceleration and deceleration (> 2 m·s-2).Varying the pitch size during the small-sided games (i.e. dynamic condition) could be an interesting constraint to be considered by soccer coaches in order to enhance task variability.

Comparison of the Physical Response During Official Matches and Small-Sided Games in International Cerebral Palsy Footballers: Implications for Evidence-Based Classification

This study aimed to analyze whether there are differences and associations in the physical responses in international-level cerebral palsy footballers between official matches and 2v2 small-sided games (2v2-SSG). One hundred seventy international cerebral palsy footballers participated in this study during three international championships. The physical responses of mean and maximum velocities, total distance, distance covered at different intensities, short-term actions, and player load were collected during 2v2-SSG and the real competition. The mean velocity, total distance, jogging, medium- and high-intensity distances, the number of moderate/high accelerations, decelerations, and player load were relatively higher in the 2v2-SSG than in the official matches. Even though the 2v2-SSG could become an appropriate drill to include during the classification process, due to the differences between a 2v2-SSG and the official competition, it is necessary to deepen the scientific knowledge for developing observation methods during real competition to strengthen the relationships between eligible impairments and activity limitation.

Techniques to derive and clean acceleration and deceleration data of athlete tracking technologies in team sports: A scoping review

The application of acceleration and deceleration data as a measure of an athlete's physical performance is common practice in team sports. Acceleration and deceleration are monitored with athlete tracking technologies during training and games to quantify training load, prevent injury and enhance performance. However, inconsistencies exist throughout the literature in the reported methodological procedures used to quantify acceleration and deceleration. The object of this review was to systematically map and provide a summary of the methodological procedures being used on acceleration and deceleration data obtained from athlete tracking technologies in team sports and describe the applications of the data. Systematic searches of multiple databases were undertaken. To be included, studies must have investigated full body acceleration and/or deceleration data of athlete tracking technologies. The search identified 276 eligible studies. Most studies (60%) did not provide information on how the data was derived and what sequence of steps were taken to clean the data. Acceleration and deceleration data were commonly applied to quantify and describe movement demands using effort metrics. This scoping review identified research gaps in the methodological procedures and deriving and cleaning techniques that warrant future research focussing on their effect on acceleration and deceleration data.

WORKLOAD CHARACTERISTICS IN THE FITNESS TRAINING OF CHINESE ATHLETES

ABSTRACT Introduction: In modern gymnastics, there are high demands for the physical quality of Chinese athletes. Objectives: This paper mainly studies whether the workload of Chinese gymnasts can support the corresponding high-intensity training in the training process. Methods: Experimental scientific research methods and statistical analysis are used to conduct a long-term study on dozens of gymnasts in Chinese schools and draw the workload curves of these gymnasts during gymnastic exercises. We try to determine the effective correlation between the athlete's body load and physical training and body shape. Results: During the training of gymnasts, heart rates can briefly exceed 190 beats per minute. Conclusion: In the training process of different gymnasts, the gymnasts’ heart rates show obvious differences. Therefore, the use of scientific and reasonable training strategies can effectively improve the ability of athletes’ hearts to withstand high-intensity exercise loads and help improve the gymnast's performance. Level of evidence II; Therapeutic studies - investigation of treatment results.

Influence of Pitch Size on Short-Term High Intensity Actions and Body Impacts in Soccer Sided Games

The aim of this study was to compare external training loads between small-sided games (SSGs) and largesided games (LSGs) in soccer players. Twenty outfield soccer players (14.8 ± 0.6 years old) who competed in the Spanish U16 Provincial Division and belonged to the same team participated in the study. The soccer sided games were played at different individual interaction space (IIS) per player (i.e., SSG = 100 m² and LSG = 200 m²) and were disputed in the same format (five-a-side plus goalkeepers) on two different pitch sizes (i.e., 38 x 26 vs. 53 x 37 m) defending an official soccer-goal. The sided games' duration was 4 bouts of 6 min with 2 min rest intervals between bouts. The results of this study showed no meaningful differences in the total distance and intensity of accelerations and decelerations between SSGs and LSGs except for the lower distance covered at medium intensity (2.5 - 4 m·s^-2) observed during LSGs (-10.2%; ES (effect size): -0.51). Players registered greater sprints, maximum velocity (Vel_max) and body impacts at different intensities (i.e., I5-6g, I6-6.5g, I6.5-7g, I7-8g, I8-10g,) in LSGs in comparison to SSGs. These findings suggest that an increase in the pitch size (i.e., IIS per player) can induce higher external loads for soccer players.

Is impaired coordination related to match physical load in footballers with cerebral palsy of different sport classes?

Impaired coordination is a characteristic feature in cerebral palsy (CP) football players. This study aimed to determine the relationships of three coordination tests with match physical load during competition of para-footballers from different sport classes. Records from 259 para-footballers from 25 national teams were obtained in four international competitions held in 2018 and 2019. The three coordination tests were conducted prior to competition (i.e., rapid heel-toe, side-stepping, and split jumps), and physical match load was recorded by GPS devices during the real game: i.e., maximum/mean, total distance, distance covered at different speed zones, number of accelerations/decelerations at different intensities, and player load. FT1 and FT3 players have the lowest and highest performance in all the coordination tests, respectively, but inconclusive between-groups differences were obtained (p=0.022‒0.238). Split jumps and side-stepping tests are associated with the performance of moderate and high accelerations during competition (r = -0.20‒0.71; p<0.01). Significant correlations (r = 0.36‒0.71; p<0.01) were obtained between all the coordination measures. Coordination tests better discriminate those with more severe impairments and some evidence for the validity of the new CP football sport classes is provided. Further research is necessary to identify the portion of the variance in sports performance that coordination explains.

Physical Demands of U10 Players in a 7-a-Side Soccer Tournament Depending on the Playing Position and Level of Opponents in Consecutive Matches Using Global Positioning Systems (GPS)

The aim of this study was to analyse the physical demands of U10 players in a 7-a-side-soccer tournament based on the playing positions in 6 consecutive matches by global positioning systems (GPS). Variables of total distance, relative distance in different speed zones, maximum speed, time interval between accelerations, maximum speed acceleration, maximum acceleration, acceleration distance and the number of high-intensity accelerations were analysed. Differences between playing positions were found in the total distance covered by the midfielders. They covered higher total distances than the defenders (+1167 m; 95% CI: 411 to 1922 m; effect size (ES) = 1.41; p < 0.05) and forwards (+1388 m; CI 95%: 712 a 2063 m; TE = 0.85; p < 0.05). The total covered distance increased in the final rounds with respect to the group stage (p < 0.05; ES: 0.44 to 1.62), and high-intensity actions, such as the number of accelerations, were greater in the final rounds compared to the group stage (p < 0.05; ES: 0.44 to 1.62). The physical performance of young football players in a tournament with consecutive matches on a 40 × 62 m football field on the same day is influenced by the playing position and dependent on the level difference between opponents.

Global Positioning System Analysis of Physical Demands in Small and Large-Sided Games with Floaters and Official Matches in the Process of Return to Play in High Level Soccer Players

The aim of this study was twofold: (i) to analyze the physical demands in the return to play (RTP) process of high-level soccer players in the role of floater in different soccer sided games (SGs) formats (i.e., 4vs4 + 2 and 8vs8 + 1); and (ii) to analyze the differences in physical demands encountered by regular and floater players among the SGs formats and official matches by means of global positioning system technology (GPS APEX pod, North Ireland) was used. Twenty-six highly trained, male soccer players (U16 years) participated in this investigation. Players were classified into two groups: 23 regular and 3 floater players, a total of eight SGs were analyzed, which involved the recording of 80 observations of regular and floater players. Match-play players showed most likely-probable differences in distance covered at high-intensity per minute (D > 14.4/min), at high-speed running per minute (D > 21/min), and peak velocity (Vpeak) in comparison to floaters in the 8vs8 + 1 LSG (large-side-games), and presented most likely differences in accelerations >2/min in comparison to match-play players. Therefore, the use of floaters during the last phase of the RTP (return to play) seems to be a useful strategy for progressive reintroduction into specific training (1) floater in the 4vs4 + 2 SSG; (2) floater in the 8vs8 + 1 LSG; (3) regular player in the 4vs4 + 2 SSG; and (4) regular player in the 8vs8 + 1 LSG before starting full trainings and returning to competition.

Effects of including endurance and speed sessions within small-sided soccer games periodization on physical fitness

The main aim of this study was to analyse the effects of including additional speed and endurance sessions during small-sided games (SSG) training periodization on physical fitness in professional soccer players. Sixteen outfield players (age = 25.6 ± 7.6 years) who competed in the First Division of a European League participated in this study. Players were randomly assigned to perform only the SSG periodization (G-SSG group) or to add endurance and speed training contents to the SSG (ES-SSG group). Before and after the 6-week experimental period, a Yo-Yo Intermittent Recovery Test level 1 (YYIR1) and a 40 m sprinting test were performed. Rating of perceived exertion (RPE) was also measured after each training session. The G-SSG group showed a large improvement in the YYIR1 performance (p = 0.018–0.028; ES = 0.521–0.576) after the training programme, whereas no significant changes were observed for the ES-SSG group (p = 0.763–1.000; ES = 0.000–0.014). In addition, no significant differences (p > 0.05, ES = 0.005–361, trivial to small) in sprint performance at 5 and 10 m intervals up to 40 m were observed at post-training in comparison to pre-training evaluation in G-SSG and ES-SSG groups. No significant differences (p > 0.05) between groups were observed at baseline in the YYIR1 test. The 6-week SSG training supported with only six endurance and speed training sessions was no more effective than well-organized SSG alone for improving running endurance in professional soccer players.

Session-to-session variations in external load measures during small-sided games in professional soccer players

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

Relationships between Players’ Physical Performance and Small-Sided Game External Responses in a Youth Soccer Training Context

The aim of this study was twofold: 1) To compare players’ physical performance and small-sided game (SSG) external responses among three young soccer age categories (i.e., under 14 (U14), under 16 (U16), and under 18 (U18)); and 2) to examine their relationships among physical performance and SSG external responses in each age category. Players’ physical performance was evaluated via several tests and external responses were collected during a four vs. four plus goalkeepers SSG. Main results showed that while older players presented better linear straight sprinting tests (LSSTs) (U18 and U16 vs. U14, p < 0.01), repeated sprint ability (RSA) (U18 vs. U16 and U14 p < 0.01), and change of direction ability (CODA) (U18 and U16 vs. U14, p < 0.01, ES = 2.34−2.72) performances, these differences were not consistent with their SSG external responses (U16 vs. U14, p < 0.01; U18 vs. U16, p < 0.01). Conversely, higher number of associations between players’ physical performance and SSG external responses were found in younger players in comparison to the older ones. These results suggest that while greater physical performance in younger players (i.e., U14) could allow them to exhibit higher external responses, greater physical performance did not influence older players’ (i.e., U18) SSG external responses.

Running-based high-intensity interval training vs. small-sided game training programs: effects on the physical performance, psychophysiological responses and technical skills in young soccer players

This study aimed to compare the effects of 5-week running-based high-intensity interval training (HIIT) vs. small-sided game training (SSG) on the physical performance, psychophysiological responses and technical skills in young soccer players. Twenty young male soccer players (age: 14.2±0.5 years, height: 161.8±7.9 cm) participated in this study and were assigned to two groups: the HIIT group (n=10) and SSG group (n=10). Both groups trained twice per week with a similar total training duration. The SSG consisted of two 5–9 minutes of 2-a-side with 2-minute passive rest periods, whereas the HIIT consisted of 12–20 minutes of continuous runs at intensities (90 to 95%) related to the velocity obtained in the 30–15 intermittent fitness test. Before and after the 5-week training periods the following tests were completed: maximum oxygen consumption (VO_2max) from the Yo-Yo Intermittent Recovery Test level 1 (YYIRTL-1), 10–30-m sprint test, countermovement jump [CMJ], squat jump [SJ], and drop jump [DJ]), 1000-m run test, zigzag agility, repeated sprint ability, 30–15 intermittent fitness test and speed dribbling ability test. Our results revealed meaningful improvements in YYIRTL-1 performance (SSG: +12.8%, standardized effect size [d]=-1.46; HIIT: +16.4%, d=3.27 and VO_2max (SSG: +3.3%, d=-1.48; HIIT: +4.3%, d=2.61). There was a meaningful greater improvement in agility and technical test performances following the SSG training compared with the HIIT (p ≤ 0.05, d=ranging from 0.92 to 1.99). By contrast, the HIIT group showed meaningfully higher performance responses in terms of the 1000-m running time and repeated sprint test ability (p ≤ 0.05, d=ranging from 0.90 to 2.06). These results confirmed that SSG training might be a more effective training regime to improve technical ability and agility with greater enjoyment, whereas HIIT might be more suitable for speed-based conditioning in young soccer players.

Acceleration intensity is an important contributor to the external and internal training load demands of repeated sprint exercises in soccer players

The aim of this study was to evaluate the effect of acceleration on the external and internal load during repeated sprint exercises (RSE). This study used a cross-over design. Sixteen soccer players were included (mean ± SDs: age 21 ± 1 years; weight 71.1 ± 7.7 kg). RSE was 3 sets of 7 × 30 m sprints with 25 s and 3 min recovery between sprints and sets, respectively. RSE was performed using two protocols requiring either 10 m maximal acceleration (2.12 m^.s^-2 [RSE-MA]) or 10 m submaximal acceleration (1.66 m^.s^-2 [RSE-SA]). Global positioning systems (10 Hz; STATSports, Viper) were utilized to collect: high speed running (HSR), dynamic stress load (DSL), Heart Rate (HR) peak, time >85% HR peak, respiratory (RPEres) and muscular (RPEmus) rating of perceived exertion. RSE-MA induced higher load than RSE-SA in HSR (p = 0.037, ES = 0.20), DSL (p = 0.027, ES = 0.43), HR peak (p = 0.025, ES = 0.47), Time >85% HR peak (p = 0.028, ES = 1.11), RPEres (p = 0.001, ES = 1.10), and RPEmus (p = 0.001, ES = 0.73). This study shows that a different acceleration intensity in a RSE (MA vs. SA) impacts external and internal training load parameters.

The influence of offside rule and pitch sizes on the youth soccer players' small-sided games external loads

The aim was to analyse the influence of the offside rule and pitch sizes on the external loads encountered by young soccer players during small-sided games (SSGs). Twenty-four U12 soccer players belonged to the same Spanish Performance Soccer Academy participated in the study. Each player participated in six different SSGs attending to the offside rule (i.e., offside not applicable [NOS] and with offside [WOS]) and the pitch sizes (i.e., individual interaction space [IIS] of 25, 50 and 75 m² per player). The obtained data included measures of external loads by global positioning systems. Players covered higher total distance and greater distances at jogging (8-12.9 km·h^-1), cruising (13.0-16.0 km·h^-1) and sprinting (>16.0 km·h^-1) in NOS₇₅ and WOS₇₅ SSGs (p < 0.01; d = 0.65-6.60). Besides, in the NOS₇₅ SSG, the total distance and the distance at cruising were higher in respect to WOS₇₅ (p < 0.01; d = 0.63-0.82). In addition, players performed lower sprints (p < 0.01; d = 1.17-1.71) and achieved lower V_max (p > 0.05; d = 1.10-1.88) during NOS₂₅ and WOS₂₅ SSGs. These findings could provide relevant information for coaches in order to apply different pitch sizes and the inclusion/absence of the offside rule throughout the microcycle.

Anabolic-catabolic hormonal responses in youth soccer players during a half-season

This study sought to evaluate the hormonal response (i.e. total testosterone, free testosterone, cortisol, and their ratios TT/C and FT/C) in the under-19 youth soccer team (n = 18) throughout a six-month period. All sport medical examinations were conducted four times: before the beginning of the preparation period (T1), just after preparation period (T2), in the middle of the competitive period (T3), and at the end of the season (T4). The cortisol concentration was decreased at the T3 (-16.9%; p = 0.014), then increased at the T2 (16.8%; p = 0.001) and at the T4 (12.7%; p = 0.062), respectively, compared to the initial value. The analyses for total and free testosterone demonstrated no differences between the measurements. Finally, values of the TT/C and FT/C ratios were increased during the T3 (25%; p = 0.017, 24.4%; p = 0.021) in comparison with the initial measurement and decreased at the T4 (-28.9%; p = 0.001, - 30.8%; p = 0.001) in comparison with the T3. The study results showed that the lowest level of peripheral fatigue was recorded in the T3, which may suggest that a correct selection of training loads does not affect the severity of catabolic processes in youth players.