The Reliability of Linear Speed with and without Ball Possession of Pubertal Soccer Players.

Reliable fitness tests with low day-to-day and trial-to-trial variation are a prerequisite for tracking a player's performance or for identifying meaningful changes in training interventions. The present study examined the inter- and intra-session reliability of 30 m linear speed with and without ball possession as well as the reliability of a specific performance index of pubertal soccer players. A total of 40 pubertal (14.87 ± 1.23 years old) male soccer players performed two testing sessions (test-retest) separated by 72 h. Both testing sessions included a protocol consisting of two maximal trials of 30 m linear speed with and without ball possession. A performance index, indicating the difference between the two speed tests, was also calculated using two different equations (delta value and percentage value). The relative and absolute inter-session reliabilities were good/high for all testing variables (ICC = 0.957-0.995; SEM% = 0.62-8.83). There were also good/high relative and absolute intra-session reliabilities observed for all testing variables (ICC = 0.974-0.987; SEM% = 1.26-6.70%). According to the Bland-Altman plots, the differences between test-retest and trials for all observations were within the defined 95% limits of agreement. The reliable testing protocols and performance index for the evaluation of linear speed with and without ball possession, observed in this study, may be used in speed monitoring and training planning of pubertal soccer players.

Health-Promoting Effects of a Concurrent Workplace Training Program in Inactive Office Workers (HealPWorkers): A Randomized Controlled Study.

PURPOSE: To the best of our knowledge, no previous study has examined the health-promoting effects of a daily supervised concurrent workplace training program in inactive office workers. The main objective of this study was to examine the effectiveness of a 6-month workplace training program on health indices, musculoskeletal pains, functional capacity, and physical fitness in office workers. DESIGN: Randomized controlled study. SETTING: Four workplaces in the Region of Thessaly, Greece. PARTICIPANTS: A total of 36 office workers (≥6 hours/d, 5 days/wk) were randomly assigned to either a training group (TG; n = 18) or a control group (CG; n = 18). INTERVENTION: The TG participated, every working day, in a 6-month supervised concurrent (flexibility, strength, balance, aerobic) training program (120 training sessions, 2 workouts/d of 15-20 minutes) that was implemented, in small groups, at the workplace during the work shift. The CG did not participate in any training. MEASURES: Health indices (body composition, blood pressure, respiratory function), musculoskeletal pains, functional capacity (flexibility, balance), and physical fitness (maximal strength, cardiorespiratory fitness) were measured before and after the completion of the program. After the completion of the program, participants' enjoyment was assessed. ANALYSIS: Two-way analysis of variance (group × time) with repeated measures on the "time" factor. RESULTS: The statistical power, for all parameters, ranged from 0.85 to 0.94. Training group significantly increased lean body mass (3.81%); respiratory function (4.20%-4.53%); cervical, handgrip, back, and leg maximal strength (8.75%-26.55%); and functional capacity (19.71%-188.20%; P < .001-.01; Cohen's effect size: 0.80-7.21), while significant reductions were observed on body fat (7.58%), blood pressure (4.99%-8.05%), heart rate (12.80%), and musculoskeletal pains (33.33%-100%; P < .001; Cohen's effect size: 0.81-6.21). In CG, all the above variables did not change. Furthermore, a great percentage of workers (94.4%) reported high levels of enjoyment. CONCLUSION: The program "HealPWorkers" is an enjoyable exercise modality that may be safely and effectively used, to work settings, for the improvement of worker's health, overall fitness, and functional capacity.

Can sport-specific training affect vertical jumping ability during puberty?

Vertical jumping ability (VJ) is an important component for successful performance in various team sports such as volleyball, basketball, and soccer. There is evidence that the sport-specific training in these sports may affect the development of VJ throughout the developmental years. Thus, the main objective of this study was to investigate the sport-related effect (volleyball, basketball, soccer) on vertical jumping ability (VJ) and on the stretch-shortening cycle (SSC) during puberty. 320 boys (12-15 years old) - 80 basketball players (BP), 80 soccer players (SP), 80 volleyball players (VP) and 80 non-athletes (NA) - participated in the present study. VJ was evaluated by the squat jump (SJ) and countermovement jump (CMJ) tests, and the contribution of SSC was calculated. The SJ and CMJ were significantly higher in VP vs. NA at the age of 12 years old and significantly greater in all sports vs. NA at the age of 13, 14 and 15 years. Furthermore, 15-year-old VP demonstrated significantly higher SJ and CMJ compared with BP and SP (p<0.01), whereas no differences were observed between BP and SP (p>0.05). Finally, pairwise comparisons revealed non-significant sport- and age-related differences (p > .05) in SSC. The pattern of age-related increase in VJ is different between athletes and non-athletes during puberty. Furthermore, sport-specific training adaptations are evident at the age of 15 years old where VP demonstrate greater VJ than BP and SP, while in younger age groups, there are no significant differences in VJ between athletes of different sports.

Strength Profile of Hip Abductor and Adductor Muscles in Youth Elite Soccer Players.

The main objective of this study was to provide an extensive isokinetic profile of the hip joint in youth soccer players, where the literature is limited. Additionally, this study investigated the effect of age on isokinetic peak torque values of hip abductor and adductor muscles and on reciprocal muscle group torque ratios in youth soccer players at different angular velocities (30 vs. 90o/s) and muscle actions (concentric vs. eccentric). Sixty young elite male soccer players were assigned into three equal groups (n = 20): children, young adolescents and older adolescents, and performed five maximal concentric and eccentric hip-abductions and adductions at 30o/s and 90o/s. The results showed a significant increase (p < 0.05) in peak torque values from childhood to adolescence, with the exception of young adolescents vs. older adolescents where no differences were observed. The reciprocal ratios were not affected by age, but improved with an increase in angular velocity with the exception of the CON/ECC ratio that was higher at 30o/s. The data presented in this study provide an extensive isokinetic profile of hip abductor and adductor muscle strength in youth soccer players to assist both coaches and sports medicine professionals in strength monitoring and training.