Pre-season Period Research Articles

Variability of activity profile during medium-sided games in professional soccer

In Southern European countries it is very frequent to perform medium-sized games (MSG) as last training drill. We analyzed the individual variability and changes in activity patterns during MSG throughout the preseason. Activity profile during MSGs (10v10+goalkeepers, duration: 10-min, field length: 50 m, width: 90 m, area per player: 204.5 m2) was quantified using a GPS in 14 professional male players (6 defenders, 5 midfielders 5 and attackers). Inter-individual variability was higher for high-intensity (HIR), very-high speed (VHS), maximum acceleration (Accmax) and maximum deceleration (Decmax) distance (CV=25.2 to 43.3%), compared to total distance (TD), total acceleration (Acctot) and total deceleration (Dectot) distance (CV= 8.3 to 18.3%). Defenders showed higher variability in TD, HIR, VHS, Acctot and Dectot (ES= 1.30 to 11.28) compared to the other field positions, whereas attackers showed higher variability in HIR, VHS Accmax and Decmax (ES=-4.92 to 2.07) than other the field positions. Variability in TD regularly increased (ES= -2.13 to -0.91) towards the end of the preseason, while HIR and VHS variability tended to increase over the 3rd and the 4th preseason week (ES=-0.94 to -3.05). However, the behavior of variability across the preseason period was more unpredictable for Acctot and Dectot, both decreasing in the 3rd week (ES= 0.70 to 1.20), while Decmax increased in the 4th week (ES=-0.91±0.59). During MSGs, individual variability of activity differs among field positions, and tends to increase with either speed or acceleration intensity, underlining the need of an individualized approach for training load monitoring.

Injury prevention and return to play strategies in elite football: no consent between players and team coaches.

Injuries are a common problem in football. To improve prevention strategies, the players' (p) and coaches' (c) views need to be disclosed as they have a strong impact on return to play decisions. The aim of this study is to reveal current opinions with regard to injury prevention and return to play strategies to introduce new strategies in elite football. In a retrospective data analysis of elite salaried football players (n = 486) and team coaches (n = 88), a detailed investigation by means of a standardized questionnaire was carried out. In a preseason period of the 2015/16 season and as part of a large interventional research project in elite salaried German football, a request about players' and team coaches' knowledge and opinions was performed. Topics such as injury prevention, return to play after injuries, the importance of screening tests, general problems of injuries in football, or the decision-making in terms of prevention and return to play in elite football were investigated. The study revealed a high interest in injury prevention and screening tests among players and coaches (p 82.5%; c 99.1%). The participants of the study reported warm-up exercises (p 76.4%; c 74.7%), regeneration training (p 54.1%; c 56.3%), and core stability (p 53.8; c 70.1%) as the most important prevention methods, but the additional investigation of the teams' current daily training routine showed that the transfer is incomplete. Coaches are more familiar with scientific published warm-up programs like FIFA 11 + than players (42.5 vs. 12.6; p < 0.001). Knee injuries (p 90.7%; c 93.1%) and ACL injuries in particular were reported as the most severe and common problem in elite football. Players and coaches expressed different attitudes concerning return to play decisions. While players want to decide themselves (81.4%), team coaches consult medical advice ahead of the decision of return to play after injuries (83.5%; p < 0.001). Decisions against the doctor's recommendation are often made by both groups (p 64.4% vs. c 87.1%; p < 0.001). The basic knowledge of prevention and injuries is sufficient in elite football, but the transfer from theoretical knowledge to practical routine is suboptimal. The study also shows possibilities to improve the prevention process and communication between players, coaches, doctors, and physiotherapists, while there is no consent between players and coaches regarding return to play decision.

Pre-Season Training Affects Negatively the Immunological Parameters and Creatine Kinase but Not Power Performance in Young Soccer Players

The training content, volume and intensity are determinants on the training load understand, since it can lead to a chronic fatigue status that affect biochemical, immunological and performance variables. This study aimed to evaluate changes in the creatine kinase (CK) activity, white blood cells subpopulations and lower-limb power performance of U19 soccer players in accordance of the training content during pre-season period.

Differential training loads and individual fitness responses to pre-season in professional rugby union players

ABSTRACTWe aimed to compare differentiated training loads (TL) between fitness responders and non-responders to an eight-week pre-season training period in a squad of thirty-five professional rugby union players. Differential TL were calculated by multiplying player’s perceptions of breathlessness (sRPE-B) and leg muscle exertion (sRPE-L) with training duration for each completed session. Performance-based fitness measures included the Yo-Yo Intermittent Recovery Test Level 1 (YYIRTL1), 10-, 20-, and 30-m linear sprint times, countermovement jump height (CMJ) and predicted one-repetition maximum back squat (P1RM Squat). The proportion of responders (≥ 75% chance that the observed change in fitness was > typical error and smallest worthwhile change) were 37%, 50%, 52%, 82% and 70% for YYIRTL1, 20/30-m, 10-m, CMJ and P1RM Squat, respectively. Weekly sRPE-B-TL was very likely higher in YYIRTL1 responders (mean difference = 18%; ±90% confidence limits 11%), likely lower in 20/30-m (19%; ±20%) and 10-m (18%; ±17%) responders, and likely higher in CMJ responders (15%; ±16%). All other comparisons were unclear. Weekly sRPE-B discriminate between rugby union players who respond to pre-season training when compared with players who do not. Our findings support the collection of differential ratings of perceived exertion and the use of individual response analysis in team-sport athletes.

Influence of initial performance level and tactical position on the aerobic fitness in soccer players after preseason period

ABSTRACTObjectives: The purpose of this study was to examine the changes in aerobic fitness in young elite Spanish soccer players after the pre-competitive period over 12 seasons depending on the initial performance level and the tactical position.Methods: One hundred and thirty players belonging to the same reserve team of a Spanish La Liga Club participated in this study. Aerobic fitness capacity (the velocity associated with a blood lactate concentration [La]b of 3 mmol l–1 [V3]) was assessed in each season at the start of the preseason (i.e. July), Test 1 (T1), and the start of the competitive period (i.e. September), Test 2 (T2), from 1998 to 2013 season.Results: Taking all seasons together a most likely small improvement (effect size (ES) = 0.52; ±0.09) was found in V3 after preseason, but this varied from trivial to moderate among the seasons. A most likely large improvement was found for the players with lower V3 values in T1 (ES = 1.68; ±0.38) while a likely small enhancement was assigned to the group with higher V3 values (ES = 0.53; ±0.42).Conclusions: Technical staff should be cautious about affirming an improvement in aerobic fitness after preseason.

Female adolescent elite handball players are more susceptible to shoulder problems than their male counterparts

PurposeShoulder problems are frequent among senior elite handball players. The objective of this study was to assess the prevalence of shoulder problems among adolescent elite handball players and to investigate potential differences in gender, school grade, playing position and playing level.MethodsDuring the 2014 and 2015 pre-season periods, 471 players (age 15–18 years, 54% female) completed a comprehensive baseline questionnaire regarding history of any shoulder pain and shoulder problems experienced during the past season. The players were monitored weekly for one competition season (September–April) regarding shoulder problems and the amount of match and training. Generalised linear models with a binomial link function were used to calculate a prevalence ratio (PR) with 95% confidence interval (CI) to compare the subgroups of players.ResultsIn total, 110 players (23%) reported having substantial shoulder problems (defined as moderate/severe reduction in training volume, or moderate/severe reduction in performance, or complete inability to participate) at some point during the follow-up season, of which almost half reported complete inability to participate. Of those players reporting substantial problems, 43% (95% CI 39–48) did so for at least 3 consecutive weeks during the season. The prevalence was significantly higher in female players (PR 1.46, 95% 1.04–2.06) and in backcourt players (PR 1.58, 95% CI 1.08–2.32), but no differences were found for school grade (PR 1.21 95% CI 0.88–1.67) or playing level (PR 1.09 95% CI 0.76–1.56).ConclusionsThe prevalence of substantial shoulder problems in adolescent elite handball players is high, especially among females, and this warrants further studies on risk factors for shoulder injury and the development of prevention strategies in handball players already before the age of 15. These findings also highlight the importance of introducing a clinical monitoring programme on a routine basis and improving the medical support, taking gender-related aspects into consideration, at handball-profiled secondary schools.Level of evidenceII.

A prospective investigation to evaluate risk factors for lower extremity injury risk in male youth soccer players.

There is an inherent risk of injury in male youth football; however, pertinent risk factors for injury have yet to be examined. This study used a prospective cohort design with 357 elite male youth football players (aged 10-18years) assessed during the preseason period and then monitored during the season recording all non-contact lower extremity injuries. Screening tests included single leg hop for distance (SLHD); 75% of maximum hop and stick (75%Hop); single leg countermovement jump (SLCMJ); and the tuck jump assessment (TJ). Players were divided into subgroups based on chronological age. SLCMJ peak landing vertical ground reaction force (pVGRF) asymmetry was the most prominent risk factor (U11-U12s, OR 0.90, P=.04; and U15-U16s, OR 0.91, P<.001). Maturational offset (OR 0.58, P=.04), lower right leg SLCMJ pVGRF relative to body weight (OR 0.36, P=.03), and advanced chronological age (OR 3.62, P=.04) were also significantly associated with heightened injury risk in the U13-U14s, U15-U16s, and U18s, respectively. Univariate analyses showed combinations of anthropometric and movement screening risk factors were associated with heightened risk of lower extremity injury; however, there was variability across the different chronological age groups. Greater SLCMJ pVGRF asymmetry, lower right leg SLCMJ pVGRF %BW, later maturation, and advanced chronological age are potential risk factors for injury in elite male youth football players, although the strength of these relationships was often low to moderate. In addition, risk factors are likely to change at different stages of development.

Can the workload–injury relationship be moderated by improved strength, speed and repeated-sprint qualities?

ObjectivesThe aim of this study was to investigate potential moderators (i.e. lower body strength, repeated-sprint ability [RSA] and maximal velocity) of injury risk within a team-sport cohort. DesignObservational cohort study. MethodsForty male amateur hurling players (age: 26.2±4.4 year, height: 184.2±7.1cm, mass: 82.6±4.7kg) were recruited. During a two-year period, workload (session RPE×duration), injury and physical qualities were assessed. Specific physical qualities assessed were a three-repetition maximum Trapbar deadlift, 6×35-m repeated-sprint (RSA) and 5-, 10- and 20-m sprint time. All derived workload and physical quality measures were modelled against injury data using regression analysis. Odds ratios (OR) were reported against a reference group. ResultsModerate weekly loads between ≥1400 AU and ≤1900 AU were protective against injury during both the pre-season (OR: 0.44, 95% CI: 0.18–0.66) and in-season periods (OR: 0.59, 95% CI: 0.37–0.82) compared to a low load reference group (≤1200 AU). When strength was considered as a moderator of injury risk, stronger athletes were better able to tolerate the given workload at a reduced risk. Stronger athletes were also better able to tolerate larger week-to-week changes (>550–1000 AU) in workload than weaker athletes (OR=2.54–4.52). Athletes who were slower over 5-m (OR: 3.11, 95% CI: 2.33–3.87), 10-m (OR: 3.45, 95% CI: 2.11–4.13) and 20-m (OR: 3.12, 95% CI: 2.11–4.13) were at increased risk of injury compared to faster athletes. When repeated-sprint total time (RSAt) was considered as a moderator of injury risk at a given workload (≥1750 AU), athletes with better RSAt were at reduced risk compared to those with poor RSAt (OR: 5.55, 95%: 3.98–7.94). ConclusionsThese findings demonstrate that well-developed lower-body strength, RSA and speed are associated with better tolerance to higher workloads and reduced risk of injury in team-sport athletes.

Stakeholders’ understanding and perceptions of bio-banding in junior-elite football training

The purpose of this study was to investigate the understanding and perceptions of professional football academy staff, youth players and parents/carers in the use of ‘bio-banding’ during a seven week, pre-season training period. Data included a series of one-to-one semi-structured interviews and semi-structured focus groups with the three participant groups. Data were collected at three distinct times: (1) pre-bio-banded training; (2) during-bio-banded training; and (3) post-bio-banded training. Data were analyzed qualitatively using a constant comparative approach. Results suggested that there are six key themes associated with bio-banding pre-season training: (1) interpretation of bio-banding; (2) perceived disadvantages; (3) perceived advantages; (4) changes to coaching planning and practice; (5) educating stakeholders; and (6) logistical issues. This study concludes by proposing applied practitioners consider the findings as a framework to guide operationalizing bio-banding in their environment.

Variations in important aerobic fitness parameters and physical characteristics during two consecutive preseason periods in adolescent soccer players

PurposeThis study examined the variations in selected aerobic fitness parameters, namely maximum oxygen consumption (VO&lt;sub&gt;2&lt;/sub&gt;max), running velocity at VO&lt;sub&gt;2&lt;/sub&gt;max (vVO&lt;sub&gt;2&lt;/sub&gt;max), running velocity at ventilatory threshold (vAnT) and 1-minute post-exercise heart rate recovery (%HRrec) as well as height, body mass and percentage of body fat (%BF) in high-level adolescent soccer players. The relationship between %BF and VO&lt;sub&gt;2&lt;/sub&gt;max values was also analyzed.Methods25 athletes (mean age: 14.5 ± 1.3 years) were measured at the second week of the preseason period (1st period) and at the same corresponding week after a 12-month period (2nd period).ResultsVO&lt;sub&gt;2&lt;/sub&gt;max, vVO&lt;sub&gt;2&lt;/sub&gt;max and vAnT increased significantly by 6.6, 6.5 and 3.27%, respectively, from the 1st to 2nd period (&lt;i&gt;p&lt;/i&gt; ≤ 0.01 - 0.05; effect size (ES) = -0.35 - 0.66). In contrast, %HRrec remained relatively unchanged (-0.5%) during the same period (&lt;i&gt;p&lt;/i&gt; &gt; 0.05; effect size (ES) = 0.01). %BF showed a negative trend, but no significant correlation with VO&lt;sub&gt;2&lt;/sub&gt;max was found during the same period (r = -0.331; &lt;i&gt;p&lt;/i&gt; &gt; 0.05). Significant variations were found for height and body mass (2.64 and 11.17%; &lt;i&gt;p&lt;/i&gt; ≤ 0.01; effect size (ES) = -0.56 and -0.72, respectively), but not for %BF (1.34%; &lt;i&gt;p&lt;/i&gt; &gt; 0.05; effect size (ES) = -0.27).ConclusionsThis data can provide useful information regarding physiological aerobic adaptations and changes in physical characteristics as a result of a year of soccer training, including growth and maturations processes, during the specific periods tested.

A novel intervention program (CricFit) for the strength and conditioning of adolescent cricket players

PurposeThe purpose of the current investigation was to examine the effects of a 4-week field-based intervention program (CricFit) on general fitness, with the program designed to reflect the demands of the game in an adolescent population.MethodsThe total of 28 schoolboy cricketers (aged 15–19 years) were assigned to either a control (&lt;i&gt;n&lt;/i&gt; = 14) or experimental (&lt;i&gt;n&lt;/i&gt; = 14) group. Both groups performed traditional net and field-based training over a 4-week period (one net- and one field-based session), with the experimental group executing 2 additional 35–45-minute conditioning sessions per week. Prior to and post the 4-week period, measures were recorded with a test battery that was specific to the movement demands associated with intermittent sports.ResultsBoth groups showed significant (&lt;i&gt;p&lt;/i&gt; &lt; 0.05) improvements in most responses, but the changes for the experimental group were greater than those shown in the control group, likely owing to the additional conditioning sessions. Furthermore, significant (&lt;i&gt;p&lt;/i&gt; &lt; 0.05) changes were observed between the two groups for the percentage body fat, flexibility, plank time, 20-m sprint time, push ups, and 25-m shuttle distance.ConclusionsIt was concluded that the CricFit intervention program can be used by coaches and conditioning specialists to improve cricket-specific fitness throughout the pre-season period.

The effect of block and traditional periodization training models on jump and sprint performance in collegiate basketball players.

This study investigated the effect of block periodization (BP) and traditional periodization (TP) approaches on jumping and sprinting performance in collegiate basketball players during an 8-week pre-season period. Ten collegiate male basketball players (mean±SD; age: 21.5±1.7 years; body mass: 83.5±8.9 kg; stature: 192.5±5.4 cm) from the same team were equally assigned to a training group (BP or TP). BP and TP were designed with different numbers of power sessions (BP=8; TP=16) and recovery days (BP=14; TP=8). Counter-movement jump (CMJ) and 20-m sprint performance was measured prior to training commencement (baseline) and every 2 weeks thereafter (week 2, week 4, week 6 and week 8). Within-group, between-group and individual changes were assessed using magnitude-based statistics. Substantially higher (likely positive) CMJ scores were evident in week 8 compared to baseline, week 2 and week 4 with BP training. Substantially higher CMJ values were only observed in week 2 (likely positive) compared to baseline, with TP training. Sprint data showed likely negative differences in week 6 compared to baseline in both TP and BP, with no substantial differences in week 8. The only performance difference between TP and BP training was in CMJ in week 8 (very likely negative). Individual analysis showed that only three athletes demonstrated a negative predicted score (i.e. lower sprinting time) in BP, while all players following the TP model demonstrated positive predicted scores. BP training showed substantially higher jumping performance compared to TP, while no improvement in sprinting performance was observed in either training approach. Basketball coaches should consider using BP training rather than TP to train players’ jumping abilities.

Observed and Simulated Sensitivities of Spring Greenup to Preseason Climate in Northern Temperate and Boreal Regions

AbstractVegetation phenology plays an important role in regulating land‐atmosphere energy, water, and trace‐gas exchanges. Changes in spring greenup (SG) have been documented in the past half‐century in response to ongoing climate change. We use normalized difference vegetation index generated from NOAA's advanced very high resolution radiometer data in the Global Inventory Modeling and Monitoring Study project over the 1982–2005 period, coupled with climate reanalysis (Climate Research Unit‐National Centers for Environmental Prediction) to investigate the SG responses to preseason climate change in northern temperate and boreal regions. We compared these observed responses to the simulated SG responses to preseason climate inferred from the Earth system models (ESMs) participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5) over 1982–2005. The observationally inferred SG suggests that there has been an advance of about 1 days per decade between 1982 and 2005 in the northern midlatitude to high latitude, with significant spatial heterogeneity. The spatial heterogeneity of the SG advance results from heterogeneity in the change of the preseason climate as well as varied vegetation responses to the preseason climate across biomes. The SG to preseason temperature sensitivity is highest in forests other than deciduous needleleaf forests, followed by temperate grasslands and woody savannas. The SG in deciduous needleleaf forests, open shrublands, and tundra is relatively insensitive to preseason temperature. Although the extent of regions where the SG is sensitive to preseason precipitation is smaller than the extent of regions where the SG is sensitive to preseason temperature, the biomes that are more sensitive to temperature are also more sensitive to precipitation, suggesting the interactive control of temperature and precipitation. In the mean, the CMIP5 ESMs reproduced the dominant latitudinal preseason climate trends and SG advances. However, large biases in individual ESMs for the preseason period, climate, and SG sensitivity imply needed model improvements to climate prediction and phenological process parameterizations.

Seasonal Changes in Soccer Players' Body Composition and Dietary Intake Practices.

Devlin, BL, Kingsley, M, Leveritt, MD, and Belski, R. Seasonal changes in soccer players' body composition and dietary intake practices. J Strength Cond Res 31(12): 3319-3326, 2017-The aims of this study were 2-fold: to determine seasonal changes in dietary intake and body composition in elite soccer players and to evaluate the influence of self-determined individual body composition goals on dietary intake and body composition. This longitudinal, observational study assessed body composition (total mass, fat-free soft tissue mass, and fat mass) using dual-energy x-ray absorptiometry and dietary intake (energy and macronutrients) via multiple-pass 24-hour recalls, at 4 time points over a competitive season in elite soccer players from one professional club in the Australian A-League competition. Self-reported body composition goals were also recorded. Eighteen elite male soccer players took part (25 ± 5 years, 180.5 ± 7.4 cm, 75.6 ± 6.5 kg). Majority (≥67%) reported the goal to maintain weight. Fat-free soft tissue mass increased from the start of preseason (55,278 ± 5,475 g) to the start of competitive season (56,784 ± 5,168 g; p < 0.001), and these gains were maintained until the end of the season. Fat mass decreased over the preseason period (10,072 ± 2,493 g to 8,712 ± 1,432 g; p < 0.001), but increased during the latter part of the competitive season. Dietary intake practices on training days were consistent over time and low compared with sport nutrition recommendations. The self-reported body composition goals did not strongly influence dietary intake practices or changes in body composition. This study has demonstrated that body composition changes over the course of a soccer season are subtle in elite soccer players despite relatively low self-reported intake of energy and carbohydrate.

Changes in Rugby League Tackling Ability During a Competitive Season: The Relationship With Strength and Power Qualities.

Speranza, MJA, Gabbett, TJ, Greene, DA, Johnston, RD, and Sheppard, JM. Changes in rugby league tackling ability during a competitive season: the relationship with strength and power qualities. J Strength Cond Res 31(12): 3311-3318, 2017-This study examined the relationship between changes in tackling ability, and muscular strength and power during a semiprofessional rugby league competitive season. Twelve semiprofessional rugby league players (mean ± SD age, 23.3 ± 2.0 years) underwent tests of upper- and lower-body strength and power during the preseason period. Tackling ability was tested using video analysis of a standardized one-on-one tackling drill. Players repeated these tests after round 15 of a 25-match competitive season. Changes in 1 repetition maximum (1RM) squat (rs = 0.70; p < 0.02) and squat relative to body mass (rs = 0.73; p < 0.01) were significantly related to changes in tackling ability. Players with the greatest improvements in tackling ability (i.e., "responders") retained 1RM squat (effect size, ES = 0.85, p = 0.09) and squat relative to body mass (ES = 0.82, p = 0.15) to a greater extent than the "nonresponders." The results of this study suggest that players who retained lower-body strength were able to improve tackling ability during the competitive season, whereas reductions in lower-body strength were associated with decrements in tackling ability. This study highlights the importance of the development and maintenance of lower-body muscular strength for effective tackling performance throughout the rugby league season.

A prospective cohort study identifying risk factors for shoulder injuries in adolescent elite handball players: the Karolinska Handball Study (KHAST) study protocol

BackgroundHandball is a physical contact sport that includes frequent overhead throwing, and this combination leads to a high rate of shoulder injuries. Several factors have been associated with shoulder injuries in overhead athletes, but strong scientific evidence is lacking for most suggested risk factors. We therefore designed the Karolinska Handball Study (KHAST) with the aim to identify risk factors for shoulder injuries in adolescent male and female elite handball players studying at handball-profiled secondary schools in Sweden. Secondary objectives are to investigate whether shoulder function changes during the competition season and whether the physical profile of the players changes during their time in secondary school.MethodsPlayers aged 15 to 19 years were included during the pre-season period of the 2014–2015 and the 2015–2016 seasons. At inclusion, players signed informed consent and filled in a questionnaire regarding playing position, playing level, previous handball experience, history of shoulder problems and athletic identity. Players also completed a detailed test battery at baseline evaluating the shoulder, neck and trunk. Players were then prospectively monitored weekly during the 2014–2015 and/or 2015–2016 competitive seasons regarding injuries and training/match workload. Results from the annual routine physical tests in the secondary school curriculum including bench press, deep squat, hand grip strength, clean lifts, squat jumps, counter movement jumps, <30 m sprints, chins, dips and Cooper’s test will be collected until the end of the competitive season 2017–2018. The primary outcome is the incidence of shoulder injuries and shoulder problems. The secondary outcome is the prevalence of shoulder injuries and shoulder problems.DiscussionShoulder problems are frequent among handball players and a reduction of these injuries is therefore warranted. However, in order to introduce appropriate preventive measures, a detailed understanding of the underlying risk factors is needed. Our study has a high potential to identify important risk factors for shoulder injuries in adolescent elite handball players owing to a large study sample, a high response rate, data collection during consecutive seasons, and recording of potential confounding factors.

Positional synchronization affects physical and physiological responses to preseason in professional football (soccer)

ABSTRACTThis study aimed to identify changes in tactical, physical and physiological performances in large-sided games during the preseason of elite footballers. Thirty professional football players participated in several GK+8vs.8+GK large-sided games across the first four weeks of the season. Players were monitored by GPS units and heart rate monitors to quantify physical, physiological and tactical performances. The variables were compared according to the preseason period, players’ positioning and professional experience. The training situation promoted similar physiological responses during the first and the last training period. However, players were revealed to have higher levels of positional synchronization during the last preseason period, indicating an improved tactical performance. Tactical variables seem to reflect the improvement of players’ performance during the preseason, measured in large-sided games situation, while affecting both physical and physiological demands. These results highlight the potential of positioning derived variables, concurrently to physical and physiological variables, for football training optimization.

A MONITORING STUDY ON CHANGES IN PHYSICAL PARAMETERS TO YOUNG PLAYERS THROUGHOUT 5 MONTHS OF TRAINING IN FOOTBALL TEAMS IN SHKODRA, ALBANIA

The best performance of soccer practitioners is certainly a consequence of regular football training, which also seems to bring acceleration to physical growth (Navarro F, 2000). The aim of this study was to give evidence on changes in physical parameters to young players throughout 5 months of training in football teams in Shkodra. Selection of the sample measurements were made in 2 teams of the city of Shkodra. In these measurements participated 78 boys players in the first and second phase of the measurements for a period of 5 months. The participant undertook anthropometrics parameters evaluation and performed three speed test (10m and 30m sprint test, speed and agility 10x5m). The necessary measurements for testing were: for the maximum capacity of the Vo2max oxygen (Andersen test) and strength tests. The difference between the first and second test (T2- T1) results of 10 m, presents the following values: mean of improvement 0.26 s (standard deviation 0.26 s and average error 0.04 s (p = 0.00)). Meanwhile, the difference between the results of the first and second tests of 30m velocity (improvement) is the following: average 0.18 s (standard deviation 0.37 s and average error 0.06 s (p = 0.00)). The difference between the results of the first and the second aerobic capacity tests is the following: average 26.6 m (standard deviation 126.28 m and average error of 51.55 m (p = 0.63)). The difference between the results of the first and second tests of the lower leg limbs presents the following values: mean -0.06 times (standard deviation 0.20 times and standard error of 0.03 times average (p = 0.05)). The results of the study showed the impact of training load at different stages of the training cycle for linear running speed, changes in speed, strength, and aerobic capacity to new football players in Shkodra. These results can serve as a basis for comparisons with colleagues in similar research studies. We have noticed that the speed performance and the ability to quickly change the direction of the players have improved throughout the observation period. For aerobic capacity, we did not notice a major improvement during the pre-season training period, while at the end of the season, sustainability increased slightly. We conclude that the training process in the youth plays an important role in the development of young players and positively influences the development of individual athletic performance components. Article visualizations:

Effects of Unloaded vs. Loaded Plyometrics on Speed and Power Performance of Elite Young Soccer Players.

The purpose of this study was to investigate the effects of loaded and unloaded plyometric training strategies on speed and power performance of elite young soccer players. Twenty-three under-17 male soccer players (age: 15.9 ± 1.2 years, height: 178.3 ± 8.1 cm, body-mass (BM): 68.1 ± 9.3 kg) from the same club took part in this study. The athletes were pair-matched in two training groups: loaded vertical and horizontal jumps using an haltere type handheld with a load of 8% of the athletes' body mass (LJ; n = 12) and unloaded vertical and horizontal plyometrics (UJ; n = 11). Sprinting speeds at 5-, 10-, and 20-m, mean propulsive power (MPP) relative to the players' BM in the jump squat exercise, and performance in the squat jump (SJ) and countermovement jump (CMJ) were assessed pre- and post-training period. During the experimental period, soccer players performed 12 plyometric training sessions across a 6-week preseason period. Magnitude based inferences and standardized differences were used for statistical analysis. A very likely increase in the vertical jumps was observed for the LJ group (99/01/00 and 98/02/00 for SJ and CMJ, respectively). In the UJ group a likely increase was observed for both vertical jumps (83/16/01 and 90/10/00, for SJ and CMJ, respectively). An almost certainly decrease in the sprinting velocities along the 20-m course were found in the LJ group (00/00/100 for all split distances tested). Meanwhile, in the UJ likely to very likely decreases were observed for all sprinting velocities tested (03/18/79, 01/13/86, and 00/04/96, for velocities in 5-, 10-, and 20-m, respectively). No meaningful differences were observed for the MPP in either training group (11/85/04 and 37/55/08 for LJ and UJ, respectively). In summary, under-17 professional soccer players increased jumping ability after a 6-week preseason training program, using loaded or unloaded jumps. Despite these positive adaptations, both plyometric strategies failed to produce worthwhile improvements in maximal speed and power performances, which is possible related to the interference of concurrent training effects. New training strategies should be developed to ensure adequate balance between power and endurance loads throughout short (and high-volume) soccer preseasons.

The effect of using contrast training during the pre-season period on the level of ability of muscle in junior football players

The effect of using contrast training during the pre-season period on the level of ability of muscle in junior football players