injury is evident in female youth players during this period remains to be identified. To date, no studies have examined the interaction between age and fatigue on H/Q FUNC in female youth soccer players. As injury incidence increases throughout adolescence in female soccer players ( 27 ), the aim of
Mark De Ste Croix, Abigail Priestley, Rhodri Lloyd, and Jon Oliver
Hani Al Haddad, Ben M. Simpson, Martin Buchheit, Valter Di Salvo, and Alberto Mendez-Villanueva
This study assessed the relationship between peak match speed (PMS) and maximal sprinting speed (MSS) in regard to age and playing positions. MSS and absolute PMS (PMSAbs) were collected from 180 male youth soccer players (U13–U17, 15.0 ± 1.2 y, 161.5 ± 9.2 cm, and 48.3 ± 8.7 kg). The fastest 10-m split over a 40-m sprint was used to determine MSS. PMSAbs was recorded using a global positioning system and was also expressed as a percentage of MSS (PMSRel). Sprint data were compared between age groups and between playing positions. Results showed that regardless of age and playing positions, faster players were likely to reach higher PMSAbs and possibly lower PMSRel. Despite a lower PMSAbs than in older groups (eg, 23.4 ± 1.8 vs 26.8 ± 1.9 km/h for U13 and U17, respectively, ES = 1.9 90%, confidence limits [1.6;2.1]), younger players reached a greater PMSRel (92.0% ± 6.3% vs. 87.2% ± 5.7% for U13 and U17, respectively, ES = –0.8 90% CL [–1.0;–0.5]). Playing position also affected PMSAbs and PMSRel, as strikers were likely to reach higher PMSAbs (eg, 27.0 ± 2.7 vs 23.6 ± 2.2 km/h for strikers and central midfielders, respectively, ES = 2.0 [1.7;2.2]) and PMSRel (eg, 93.6% ± 5.2% vs 85.3% ± 6.5% for strikers and central midfielders, respectively, ES = 1.0 [0.7;1.3]) than all other positions. The findings confirm that age and playing position affect the absolute and relative intensity of speed-related actions during matches.
Christine M. Salinas, Frank M. Webbe, and Trent T. Devore
We administered neurocognitive batteries to 49 youth soccer athletes (9–15 yr), who were selected from competitive soccer teams in Central Florida. We collected observational data on soccer heading, self-reported soccer heading, as well as demographics, including school, medical, and soccer history. Both the frequency and intensity of heading the ball in soccer was low in comparison with adolescents and adults. In our sample, the vast majority of soccer headings were of low to moderate intensity and direct (i.e., the incoming flight of the ball was perpendicular to the forehead). Age significantly correlated with frequent heading. Parents were reliable observers of their children’s soccer heading behavior and other at-risk behaviors during games. The majority of soccer headings were direct rather than flicks. Almost half of our participants reported headache and one-fourth reported dizziness after instances of heading the ball. Frequency of soccer heading was not related to neuropsychological score data.
Gustavo Tomazoli, Joao B. Marques, Abdulaziz Farooq, and Joao R. Silva
Purpose: To investigate the effectiveness of different individualization methods of speed zones during match play to estimate postmatch perceptual recovery in soccer. Methods: Twelve players under the age of 19 y undertook field-based assessments to determine their maximal aerobic speed (MAS) and maximal sprint speed (MSS). External load (extracted from 10-Hz GPS over 10 official matches) was measured and classified into 4 categories as follows: low-speed running, moderate-speed running, high-speed running, and sprinting. Match running distribution into different speed zones was categorized using either MAS, MSS, MAS and MSS as measures of locomotor capacities, and absolute values. Players perceived recovery status was recorded immediately postmatch (Post) and 24 (G+24H) and 48 hours (G+48H) after each game. Results: Different individualization methods resulted in distinct match outputs in each locomotor category. Perceived recovery status was lower (P < .001) at Post (3.8 [1.32], 95% confidence interval [CI], 3.6 to 4.2), G+24H (5.2 [1.48], 95% CI, 4.9 to 5.6), and G+48H (6.0 [1.22], 95% CI, 5.7 to 6.3) compared with prematch values (7.1 [1.05], 95% CI, 6.8 to 7.3). The absolute perceived recovery-status score was better associated with high-speed running using the locomotor-capacities method at Post (β = −1.7, 95% CI, −3.2 to −0.22, P = .027), G+24H (β = −2.08, 95% CI, −3.22 to −0.95, P = .001), and G+48H (β = −1.32, 95% CI, −2.2 to −0.4, P = .004) compared with other individualization methods. Conclusion: The authors’ results suggest that locomotor capacities may better characterize the match intensity distribution (particularly for the high-speed running and sprinting categories) and should be preferred over MAS and MSS to estimate perceived recovery.
Terry L. Rizzo, Paul Bishop, and David Tobar
Attitudes and selected attributes of youth soccer coaches (N = 82, 18 women, 63 men, and one person who did not identify his/her gender) toward coaching a player with mild mental retardation (MMR) were assessed by Coaches’ Attitudes Toward Players With Disabilities (CAP-S) survey. Intereorrelations among 11 variables were reported. The highest were r = .72 between belief and attitude, and r = .57 between belief and intention. Results from a stepwise selection multiple regression procedure showed that as perceived soccer coaching competence increased, beliefs about coaching a player with MMR showed greater agreement. Results also indicated that, as perceived soccer coaching competence increased, attitudes and intention toward coaching a player with MMR improved. Perceived soccer coaching competence explained only a small amount of the variance for beliefs, attitudes, and intentions.
Ben Serrien, Maggy Goossens, and Jean-Pierre Baeyens
The aim of this article was to examine changes in elite youth volleyball players’ performance, proximal-to-distal sequencing, and coordination variability of the spike motion between the start and after 1 year of a talent development program. Eight boys and eight girls in late puberty/early adolescence were measured with 3D motion capturing for 2 consecutive years. Performance and performance variability increased and decreased, respectively, but both changes were not significantly correlated with growth. Gender differences were identified for proximal-to-distal sequencing, but a very strong similarity between both years was observed for all seven degrees of freedom (pelvis and trunk rotation, trunk flexion, shoulder horizontal adduction, shoulder internal rotation, elbow extension, and wrist flexion). The fact that this sequence was kept stable, despite marked growth effects, likely indicates that this sequence is biomechanically efficient and the motor control systems try to preserve it. Coordination variability was analyzed by coordination profiling with self-organizing maps. The decrease in coordination variability correlated strongly and significantly with increase in body height. Participants with stronger growth rates were observed to show smaller decreases in coordination variability, which possibly represents a mechanism to explore various coordination patterns to adapt to the more rapidly changing organismic constraints.
Jaime Fernandez-Fernandez, Alejandro Lopez-Valenciano, Jose Vicente Garcia-Tormo, David Cabello-Manrique, and Juan García-López
Purpose: To analyze the influence of playing 2 consecutive prolonged badminton matches on the shoulder strength and range of motion (ROM) of young players. Methods: Sixteen elite junior badminton players (12 males and 4 females; mean (SD): age 16.2 [0.8] years, body mass 63.5 [6.6] kg, height 173.2 [6.3] cm) participated in a cross-sectional study. Shoulder internal (IR)/external rotation (ER) ROM and IR/ER strength measures were conducted before and after 2 consecutive prolonged (ie, 35 min) matches and 12 hours after the second match. Results: After consecutive matches, IR strength of the dominant side and ER strength of the dominant and nondominant sides (effect size [ES] = 0.20–0.57) were reduced. Shoulder total ROM of the dominant side was decreased (ES = 0.80), while on the nondominant side, IR (ES = 0.66) was also decreased. After 12 hours, results showed decreased values in the IR/ER strength of the dominant side (ES = 0.36–1.00), as well as ER of both dominant and nondominant sides (ES = 0.30–0.59). IR ROM of the nondominant side (ES = 0.69) was also decreased. Conclusion: Present results showed that 2 consecutive matches on the same day with brief rest periods led to significant impairments in shoulder strength and ROM levels. These data can potentially elucidate the need for shoulder-specific training and recovery strategies prior to or during competitions.
Lasse Ishøi, Kasper Krommes, Mathias F. Nielsen, Kasper B. Thornton, Per Hölmich, Per Aagaard, Juan J.J. Penalver, and Kristian Thorborg
soccer players demonstrate a progressive increase in quadriceps strength from U-8 up to the U-18, whereas hamstring strength seems to plateau at around U-15 to U-18. 10 , 11 This indicates a nonuniform development in quadriceps and hamstring muscle strength in youth players, and that maximal hamstring
Nick Dobbin, Jamie Highton, Samantha L. Moss, and Craig Twist
Sciences ethics commitee, 729 male youth (n = 235), academy (n = 362), and senior (n = 132) rugby league players from 12 individual clubs participated in the study (Table 1 ). Youth players were affiliated with a scholarship program, and academy players were contracted to a professional club. Senior
Nick Dobbin, Richard Hunwicks, Ben Jones, Kevin Till, Jamie Highton, and Craig Twist
.04 [1.66–2.42]). Due to the large difference in body mass (ES 1.32 [0.98–1.66]), PF data were scaled to account for this difference. Senior players generated significantly greater force than youth players with both ratio (26.07 ± 3.08 cf 21.58 ± 3.71 N/kg, t = 4.936, P < .001, ES = 1.32 [0