Effects of plyometric training on jumping performance in junior basketball players.

BACKGROUND: Although the plyometric training has proved its efficiency, it remains generally unknown whether a limited amount of plyometric training could improve movements in subjects who already demonstrate high level of performance. METHODS: Three different training regimens were performed in order to study effects of plyometric training on elite junior basketball players. While control group (CG) participated only in the regular midseason training activity, another two groups performed a limited amount of plyometric training employing drop jumps from the height of either 50 cm (EG-50) or 100 cm (EG-100). The height of the maximal vertical jump (CMJ), as well as the maximal voluntary force (F) and the rate of force development (RFD) of hip and knee extensors were tested prior to and after the training. RESULTS: An increase in CMJ (4.8 and 5.6 cm in EG-50 and EG-100, respectively), as well as in F of hip extensors and RFD of knee extensors was observed in both experimental groups, while no significant changes were recorded in CG. When the pretest scores were used as a covariate, both experimental groups demonstrated higher increase in CMJ and RFD of knee extensors then CG. However, no differences were observed between EG-50 and EG-100. The multiple correlation between four isometric parameters and CMJ revealed R2=0.29. CONCLUSIONS: A limited amount of plyometric training could improve jumping performance in elite junior basketball players and this improvement could be partly related with an increase in F of hip extensors and RFD of knee extensors. However, neither of the two initial heights of the applied drop jumps proved to be more effective.     

Effects of traditional balance and slackline training on physical performance and perceived enjoyment in young soccer players

The aim of this study was to evaluate the effects of 12-week balance and slackline training programs on physical performance and perceived enjoyment scale in young soccer players. Forty-one preadolescent soccer players were assigned to two experimental groups performing traditional balance (BLT) or slackline training (SLT), and a control group. Pre-post assessment encompassed Balance Error Scoring System (BESS), Star Excursion Balance test (SEBT), sprint with 90° turns (S90), and countermovement jump (CMJ). The rate of perceived enjoyment scale (PACES) was applied at the end of the experimental period. SLT and BLT improved similarly in BESS, SEBT and S90. No changes were detected in the CMJ. Regarding PACES score, SLT presented significantly higher values than BLT. Young athletes may benefit from a motivating training approach, thus, a designed program based on slackline drills should be preferable to improve physical performance in terms of balance and change of direction ability in preadolescent soccer players.     

Effects of in-season short-term plyometric training on jumping and agility performance of basketball players

The purpose of this investigation was to examine the effects of in-season plyometric training program on power and agility performance in young male basketball players. Twenty intermediate basketball players (age 20.1 ± 1.3 years; height 181.1 ± 8.5 cm; body mass 78.8 ± 5 kg) from Division I province team volunteered to participate in this study and were randomly divided into two groups: plyometric training (PL; n = 10) and control group (CG; n = 10). Plyometric training took place twice weekly for 6 weeks including three sets of 15 repetitions of depth jump (from 45-cm box height), vertical jump, and standing long jump, in addition to regular basketball practice of the team. Vertical jump (VJ), standing long jump (SLJ), 4 × 9-m shuttle run, agility t test (ATT), and Illinois Agility Test (IAT) were measured at pre- and post-training. The PL group showed significant improvement (P < 0.05) in VJ (10.21 ± 2.72 cm), SLJ (21.15 ± 8.10 cm), 4 × 9-m shuttle run (0.62 ± 0.28 s), ATT (1.16 ± 0.57 s), and IAT (1.17 ± 0.65 s) after a 6-week training period and compared to CG. It can be concluded that a 6-week in-season plyometric training program has positive effects for improving power and agility performance in young male basketball players and this study provides support for coaches and basketball players who use this training method during competitive phase.     

Impact of Ramadan on physical performance in professional soccer players

Objective

Ramadan is a period of daylight abstention from liquid or solid nutrients. As sports continue to be scheduled, an understanding of the effects of Ramadan on Muslim athletes is warranted.

Design

Two Algerian professional soccer teams (55 men) were studied. Field tests of physical and soccer performance were collected before, at the end and 2 weeks after Ramadan in 2004. Players were queried on sleeping habits and personal perception of training and match performance.

Setting

Field setting at club training ground.

Main outcome measures

Performance on fitness and skill tests.

Results

Performance declined significantly (p<0.05) for speed, agility, dribbling speed and endurance, and most stayed low after the conclusion of Ramadan. Nearly 70% of the players thought that their training and performance were adversely affected during the fast.

Conclusions

The phase shift of food intake and disruption of sleep patterns affect actual and perceived physical performance. Islamic athletes need to explore strategies that will maximise performance during Ramadan.Soccer''s popularity crosses geographical, political and religious boundaries. One of the major religions of the world is Islam, with over one billion people in multiple nations living under Islamic laws where soccer is one of the major spectator and participant sports.The major religious period of the Islamic calendar is Ramadan, when healthy post‐pubescent Muslims fast, without damaging their health, from sunrise to sunset for the 4‐week period. Muslims are invited to abstain from all types of liquid or solid nutrient intake as well as all unhealthy or aggressive behaviour during this period of purification, internal meditation and regeneration.Physiological and clinical effects of Ramadan on hormonal, metabolic and behavioural responses have been the focus of study. Limited data on physical performance show that submaximal factors (ie, heart rate) are affected little whereas maximal work declines.¹ Because football is contested internationally and matches continue to be scheduled during Ramadan, our aim was to learn how Ramadan affects the performance of competitive soccer players.     

Field-based physical performance of elite and sub-elite middle-adolescent soccer players

The aim of the current study was to evaluate field-based physical performance of under 16 years (U16) elite and sub-elite soccer players. Forty elite (n = 20) and sub-elite (n = 20) soccer players were enrolled and tested for countermovement jump (CMJ), 10-m sprint and agility, in terms of sprint with 90° turns (S90), S90 with ball, Slalom, Slalom with ball, and reactive agility (RAT). Statistical and practical significant differences were observed in CMJ, S90 and RAT between elite and sub-elite. Elite players exhibited a likely better performance in Slalom, Slalom with ball and S90 with ball despite a non-significant difference by level of play. Concerning sprint ability, both groups showed similar performance in the 10-m sprint. Countermovement jump and agility tests are field-based physical assessments recommended to better distinguish between U16 elite and sub-elite soccer players.     

The effect of age on between-match physical performance variability in professional soccer players

ABSTRACT

This study aimed to analyse the effect of age on between-match variability of physical performance in professional soccer players. For this purpose, observations on entire match performance were collected on 787 professional soccer players competing in the first or second division of Spanish league during the 2017–2018 season. Players were classified into six groups according to their age: G1 (≤22.5 years), G2 (22.6–25.1 years), G3 (25.2–27.5 years), G4 (27.6–30.1 years), G5 (30.2–33.1 years) and G6 (≥33.2 years). Coefficients of variation (CVs) were calculated individually for each player and performance variable: total distance, low- intensity, medium-intensity, high-intensity running (HIR), sprinting, number of HIR, number of sprints, average speed and maximal speed. The main finding of this study was that players under 25.2 years (G1 and G2) showed lower CVs for high-intensity activities (HIR and sprinting) in comparison with players over 33.1 years (G6). These findings provide useful information for soccer coaches, who could put extra attention on physical performance of the oldest players when they have to play an entire match, because their performance is more variable and uncertain in comparison with the youngest.     

Positional characteristics of physical performance in Division I college female soccer players

AIM: The purpose of this investigation was to determine and compare positional characteristics (physical and physiological) of Division I college female soccer players. METHODS: Sixty-four university soccer players volunteered to participate and were evaluated at the end of their spring season. Test items included height and body mass, acceleration (9.14 m), speed (18.28 and 36.58 m), agility (Pro-agility and Illinois), lower body power (countermovement jump), and estimated aerobic capacity (20 meter beep test). RESULTS: Mean (+/-SD) height and body mass were 168.4+/-5.9 cm and 64.8+/-5.9 kg, respectively. No significant differences were observed between positions, however defenders and keepers tended to be taller and heavier compared to forwards and midfielders. Positional differences did not appear for any of the other performance tests. Yet, defenders tended to show slightly slower times for the speed and agility tests while keepers tended to be slower on the agility tests compared to forwards and midfielders. Aerobic capacity was similar across the four positions. CONCLUSIONS: Similar physical and physiological characteristics were found within this sample of Division I female college soccer players.     

Non-dominant leg training improves the bilateral motor performance of soccer players

The aim of this experiment was to evaluate bilateral motor performance effects from training the non-dominant leg of competitive soccer players. The subjects were 39 soccer players, 15-20 years of age, performance-matched and randomly divided into a training group (n = 18) and a control group (n = 21) both belonging to the same team. Both groups were tested by using two standardised foot-tapping tests and three soccer-specific tests. The training intervention consisted of the experimental group participating in all parts of their soccer training except full play, using the non-dominant leg for 8 weeks. Statistical analyses for the soccer-specific tests revealed that the experimental group improved significantly as compared to the control group from the pre-test to the post-test period in their use of the trained non-dominant leg. Somewhat unexpectedly, the experimental group also improved significantly in the tests, which made use of the dominant side. The standardised foot-tapping tests revealed similar results. The results might be explained by improved generalised motor programmes, or from a Dynamic Systems Approach, indicating that the actual training relates to the handling of all the information available to the subject in the situation, and that the body self-organises the motor performance.     

Aquatic plyometric training increases vertical jump in female volleyball players

PURPOSE: Numerous studies have reported that land-based plyometrics can improve muscular strength, joint stability, and vertical jump (VJ) in athletes; however, due to the intense nature of plyometric training, the potential for acute muscle soreness or even musculoskeletal injury exists. Performance of aquatic plyometric training (APT) could lead to similar benefits, but with reduced risks due to the buoyancy of water. Unfortunately, there is little information regarding the efficacy of APT. Thus, the purpose of this study was to examine the effects of APT on VJ and muscular strength in volleyball players. METHODS: Nineteen female volleyball players (aged 15 +/- 1 yr) were randomly assigned to perform 6 wk of APT or flexibility exercises (CON) twice weekly, both in addition to traditional preseason volleyball training. Testing of leg strength was performed at baseline and after 6 wk, and VJ was measured at baseline and after 2, 4, and 6 wk. RESULTS: Similar increases in VJ were observed in both groups after 4 wk (APT = 3.1%, CON = 4.9%; both P < 0.05); however, the APT group improved by an additional 8% (P < 0.05) from week 4 to week 6, whereas there was no further improvement in the CON group (-0.9%; P = NS). After 6 wk, both groups displayed significant improvements in concentric peak torque during knee extension and flexion at 60 and 180 degrees x s(-1) (all P < 0.05). CONCLUSIONS: The combination of APT and volleyball training resulted in larger improvements in VJ than in the CON group. Thus, given the likely reduction in muscle soreness with APT versus land-based plyometrics, APT appears to be a promising training option.     

Predictive modelling of the physical demands during training and competition in professional soccer players

ObjectivesThe present study aimed to predict the cut-off point-values that best differentiate the physical demands of training and competition tasks including friendly matches (FM), small sided games (SSG), large sided games (LSG), mini-goal games (MG) and ball circuit-training (CT) in professional soccer players.DesignExperimental randomized controlled trial.MethodsFourteen professional players participated in all tasks with the CT, SSG and MG consisting of 8 repetitions of 4-min game play, interspersed by 2-min of active recovery. The training data were compared to the first 32-min of the LSG and two competitive FM per player. All movement patterns from walking to sprint running were recorded using 10 Hz GPS devices while player perception of exertion was recorded via a visual analogue scale, post-task. Decision tree induction was applied to the dataset to assess the cut-off point-values from four training drills (SSG, LSG, MG, and CT) and FM for every parameter combination.ResultsDistance covered during jogging (2.3–3.3 m/s; >436 m), number of decelerations (≤730.5) and accelerations (≤663), and maximum velocity reached (>5.48 m/s) characterized the physical demands during competition (FM) with great variability amongst training drills.ConclusionThe use of these novel, cut-off points may aid coaches in the design and use of training drills to accurately prepare athletes for soccer competition.     

Physiological and performance effects of generic versus specific aerobic training in soccer players

The aim of this study was to compare the effects of specific (small-sided games) vs. generic (running) aerobic interval training on physical fitness and objective measures of match performance in soccer. Forty junior players were randomly assigned to either generic (n=20) or specific (n=20) interval training consisting of 4 bouts of 4 min at 90-95 % of maximum heart rate with 3 min active rest periods, completed twice a week. The following outcomes were measured at baseline (Pre), after 4 weeks of pre-season training (Mid), and after a further 8 weeks of training during the regular season (Post): maximum oxygen uptake, lactate threshold (Tlac), running economy at Tlac, a soccer-specific endurance test (Ekblom's circuit), and indices of physical performance during soccer matches (total distance and time spent standing, walking, and at low- and high-intensity running speed). Training load, as quantified by heart rate and rating of perceived exertion, was recorded during all training sessions and was similar between groups. There were significant improvements in aerobic fitness and match performance in both groups of soccer players, especially in response to the first 4 weeks of pre-season training. However, no significant differences between specific and generic aerobic interval training were found in any of the measured variables including soccer specific tests. The results of this study showed that both small-sided games and running are equally effective modes of aerobic interval training in junior soccer players.     

Effects of plyometric and weight training on muscle-tendon complex and jump performance

PURPOSE: The purpose of this study was to investigate the effects of plyometric and weight training protocols on the mechanical properties of muscle-tendon complex and muscle activities and performances during jumping. METHODS: Ten subjects completed 12 wk (4 d.wk(-1)) of a unilateral training program for plantar flexors. They performed plyometric training on one side (PT; hopping and drop jump using 40% of 1RM) and weight training on the other side (WT; 80% of 1RM). Tendon stiffness was measured using ultrasonography during isometric plantar flexion. Three kinds of unilateral jump heights using only ankle joint (squat jump: SJ; countermovement jump: CMJ; drop jump: DJ) on sledge apparatus were measured. During jumping, electromyographic activities were recorded from plantar flexors and tibial anterior muscle. Joint stiffness was calculated as the change in joint torque divided by the change in ankle angle during eccentric phase of DJ. RESULTS: Tendon stiffness increased significantly for WT, but not for PT. Conversely, joint stiffness increased significantly for PT, but not for WT. Whereas PT increased significantly jump heights of SJ, CMJ, and DJ, WT increased SJ only. The relative increases in jump heights were significantly greater for PT than for WT. However, there were no significant differences between PT and WT in the changes in the electromyographic activities of measured muscles during jumping. CONCLUSION: These results indicate that the jump performance gains after plyometric training are attributed to changes in the mechanical properties of muscle-tendon complex, rather than to the muscle activation strategies.