Clinical Research Directory

Combined Technical and Balance Training in U12 Soccer Players

This study was designed as a two-arm, parallel-group randomized controlled trial to investigate the effects of a combined technical and balance training program on dynamic postural control, inter-limb asymmetry, and soccer-specific performance in young soccer players. Thirty male U12 soccer players were randomly allocated to an experimental group (n = 15) or a control group (n = 15). The intervention lasted 8 weeks, with two training sessions per week. The experimental group performed additional exercises specifically targeting the non-dominant leg, including three technical exercises focused on non-dominant-leg skills and one dynamic bipodal balance exercise performed on unstable balance cushions. The control group continued their conventional soccer training program without additional targeted exercises. Assessments were performed before and after the intervention period. Dynamic postural control was evaluated using the Star Excursion Balance Test (SEBT). Soccer-specific performance was assessed using technical skill tests, including shooting, juggling, and dribbling performance. Inter-limb asymmetry was evaluated by comparing dominant and non-dominant limb performance. The primary objective was to determine whether a combined training approach emphasizing non-dominant-leg technical practice and dynamic balance stimulation could improve limb-specific performance and reduce inter-limb differences in young soccer players. The study was conducted under ethical approval from the Deanship of Scientific Research at Palestine Technical University-Kadoorie. Written informed consent was obtained from the parents or legal guardians of all participants before participation.

Phosphatidylserine, Taurine, and Caffeine for Cognitive Fatigue in Professional Football Players

This randomized, double-blind, placebo-controlled, parallel-group trial evaluated neurocognitive fatigue resistance and football-specific decision-making following 28 days of taurine-caffeine supplementation with or without phosphatidylserine in professional male football players. Sixty-five male outfield football players from two professional clubs were randomized to placebo, taurine plus caffeine, or taurine plus caffeine plus phosphatidylserine. Neurocognitive fatigue resistance was evaluated during a standardized high-load Stroop/Flanker task, while football-specific tactical decision-making, visual-search behavior, and field-based reactive decision performance were assessed at baseline and after 28 days of supplementation.

Sex Differences in Knee Strength and Speed in Male and Female Football Players

Force-velocity (F-V) profiling is increasingly used to describe the mechanical capacities of the knee extensors and knee flexors in football, but almost all available reference data come from male players. It is not established whether male and female players differ in the parameters of the isokinetic force-velocity relationship, or whether any such differences persist once differences in body size are accounted for. This single-centre, cross-sectional observational study compared the isokinetic force-velocity profiles of the knee extensors and knee flexors between male and female competitive football players. Eligible participants were competitive players aged 18 to 35 years, training at least three times per week, free of current lower limb pain or injury and with no history of knee or hip surgery. During a single testing session, participants performed bilateral concentric isokinetic knee extension and flexion at five angular velocities (30, 60, 180, 240 and 300 degrees per second) on an isokinetic dynamometer, after a standardised warm-up, individual gravity correction and a familiarisation session. For each participant, limb and muscle group, peak torque was regressed against angular velocity to fit an individual linear torque-angular velocity relationship. The following parameters were derived: theoretical maximal torque (F0), theoretical maximal angular velocity (V0), the slope of the relationship, maximal theoretical power (Pmax), and torque and power at the extremes of the tested velocity range. The participant, defined as the mean of both limbs, was the unit of analysis. Male and female players were compared in absolute terms and after adjustment for body size, using ratio scaling to body mass, log-log allometric models and analysis of covariance with body mass and age as covariates. Secondary comparisons included the conventional hamstring-to-quadriceps ratio, inter-limb asymmetry and the orientation of the profile (F0/V0 ratio). The purpose of the study is to determine which sex differences in isokinetic force-velocity parameters are explained by body size and which persist after adjustment, in order to establish whether reference values obtained in male players can legitimately be applied to female players.

Velocity-Based vs Percentage-Based Strength Training in Young Football Players

The aim of the present study was to compare the effects of six weeks of velocity-based training (VBT) and traditional percentage-based strength training (TRD) on 20 m sprint performance, vertical jump, and aerobic capacity in elite young football players. The main research question was: Does VBT produce greater improvements than TRD in these performance markers? Researchers compared VBT with TRD to determine whether VBT leads to superior enhancements in sprint speed, jump performance, and aerobic capacity among elite young football players. Participants: Performed either VBT squat training, VBT squat plus bench press training, or TRD squat training. Completed VBT or TRD sessions three times per week for six weeks. Attended the laboratory for measurements and tests before and after the six-week training program.

Game-Based Versus Linear Sprint Training in Male Soccer Players

This randomized controlled trial investigated the effects of two different sprint training approaches on physical performance in male amateur soccer players during the competitive season. The study aimed to determine whether once-weekly game-based sprint training or linear sprint training could improve sprint performance, change-of-direction ability, hamstring strength, and maximum running velocity achieved during official matches. Thirty-six male amateur soccer players were randomly assigned in a 1:1:1 ratio to one of three groups: the Game-Based Sprint Group, the Linear Sprint Group, or the Control Group. Participants in both sprint training groups completed one additional sprint training session per week for 12 weeks while continuing their regular soccer training and competition schedule. The Linear Sprint Group performed maximal 40-meter linear sprints, whereas the Game-Based Sprint Group performed soccer-specific sprint activities that included running, ball involvement, and technical actions. The Control Group continued regular soccer training without an additional sprint-specific intervention. Sprint performance, change-of-direction performance, and right and left hamstring strength were assessed at baseline, Week 6, and Week 12. Maximum running velocity was also monitored during official matches throughout the 12-week study period. The study was designed to compare how the two sprint training approaches affected performance over time and whether changes observed during standardized testing were also reflected in maximum running velocity during competitive matches.

Effects of an Eight-Week Small-Sided Games Training Program on Aerobic Endurance and Passing Performance in Adolescent Soccer Players

Soccer requires players to combine physical fitness with technical skills throughout a match. Small-sided games (SSG) are modified soccer training sessions played with fewer players and reduced pitch dimensions. These training formats are widely used because they simulate match situations while providing high physical and technical demands. The purpose of this randomized controlled trial was to investigate whether an eight-week SSG training program improves aerobic endurance and passing performance in adolescent male soccer players. Eighteen licensed youth soccer players were randomly assigned to either an SSG training group or a control group. Both groups continued their regular soccer training, while the SSG group additionally performed structured small-sided game sessions three times per week for eight weeks. Aerobic endurance was evaluated using the Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IR1), and passing performance was assessed using the Loughborough Soccer Passing Test (LSPT). These measurements were obtained before and after the intervention. The primary objective of the study was to compare changes in aerobic endurance and passing performance between the SSG and control groups. It was hypothesized that participation in the structured SSG program would result in greater improvements in both outcomes compared with regular soccer training alone. The findings of this study are expected to provide evidence supporting the use of structured small-sided games as an effective and time-efficient training strategy for improving both physical fitness and technical performance in adolescent soccer players.