Latest research in football - week 36 - 2015

#1 Ankle inversion taping using kinesiology tape for treating medial ankle sprain in an amateur soccer player
Reference: J Phys Ther Sci. 2015 Jul;27(7):2407-8. doi: 10.1589/jpts.27.2407. Epub 2015 Jul 22.
Authors: Lee SM, Lee JH
Summary: The purpose of this study was to report the effects of ankle inversion taping using kinesiology tape in a patient with a medial ankle sprain. A 28-year-old amateur soccer player suffered a Grade 2 medial ankle sprain during a match. Ankle inversion taping was applied to the sprained ankle every day for 2 months.  His symptoms were reduced after ankle inversion taping application for 2 months. The self-reported function score, the reach distances in the Star Excursion Balance Test, and the weight-bearing ankle dorsiflexion were increased. This study showed that ankle inversion taping using kinesiology tape may be an effective therapy for a patient with a medial ankle sprain.


#2 Use of CR100 Scale for Session-RPE in Soccer and Interchangeability With CR10
Reference: Int J Sports Physiol Perform. 2015 Aug 26. [Epub ahead of print]
Authors: Fanchini M, Ferraresi I, Modena R, Schena F, Coutts AJ, Impellizzeri FM
Summary: The purpose of the study was to examine the construct validity of the session rating perceived exertion (s-RPE) assessed with the Borg CR100® scale to measure training loads in elite soccer and to examine if the CR100® is interchangeable and can provide more accurate ratings compared to the CR10® scale. Two studies were conducted. The validity of the CR100® was determined in 19-elite soccer players (age 28 ± 6 y, height 180 ± 7 cm, body mass 77 ± 6 kg) during training sessions through correlations with Edwards heart rate method (study one). The interchangeability with CR10® was assessed in 78 soccer players (age 19.3 ± 4.1 y, height 178 ± 5.9 cm, body mass 71.4 ± 6.1 kg) through Bland-Altman method and correlations between change scores in different sessions. To examine whether the CR100® is more fine graded than the CR10®, the proportion of responses corresponding to the verbal expressions were calculated (study two). Individual correlations between Edwards' and s-RPE were large to very large (0.52 to 0.85). The mean difference between the two scales was -0.3 ± 0.33 AU (90% CI -0.41 to -0.29 AU) with 95% limits of agreements 0.31 to -0.96 AU. Correlations between scales and between changes scores were nearly perfect (0.95 and 0.91 to 0.98). Ratings corresponding to the verbal anchors were 49% in CR10® and 26% in CR100®. The CR100® is valid for assessing the training load in elite soccer players. It can be used interchangeably with the CR10® and may provide more precise measures of exercise intensity.


#3 The Relative Age Effect in German Elite Youth Soccer: Implications for a Successful Career
Reference: Int J Sports Physiol Perform. 2015 Aug 26. [Epub ahead of print]
Authors: Skorski S, Faude O, Hammes D, Meyer T.
Summary: We investigated whether anthropometric profiles and fitness measures vary according to birth date distribution in the German national youth soccer teams. It was further analysed if there is a difference in the chance of becoming a professional soccer player depending on birth quarter (BQ). 554 players were divided into 6 age groups (U16-U21), each subdivided into 4 BQs. Every player performed at least one 30m-Sprint, Counter-Movement Jump (CMJ) and an incremental test to determine individual anaerobic threshold (IAT). For players performing more than one test within a team, the best one was included. Since some players were part of several different teams, a total of 832 data sets from 495 individual soccer players, all born between 1987 and 1995 divided into six age categories (U16 to U21) were included. Overall, more players were born in BQ1 compared with players in all other BQs (P < 0.05). No significant difference between BQ could be observed in any anthropometric or performance characteristics (P > 0.18). Players born in BQ4 were more likely to become professional compared to BQ1 (odds ratio: 3.04; Cl: 1.53-6.06). A relative age effect exists in elite German youth soccer but it is not explained by an advantage in anthropometric or performance-related parameters. Younger players selected into national teams have a greater chance to become professional later in their career.


#4 Health-Related Physical Fitness in Healthy Untrained Men: Effects on VO2max, Jump Performance and Flexibility of Soccer and Moderate-Intensity Continuous Running
Reference: PLoS One. 2015 Aug 25;10(8):e0135319. doi: 10.1371/journal.pone.0135319. eCollection 2015.
Authors: Milanović Z, Pantelić S, Sporiš G, Mohr M, Krustrup P
Download link: http://www.plosone.org/article/fetchObject.action?uri=info:doi/10.1371/journal.pone.0135319&representation=PDF
Summary: The purpose of this study was to determine the effects of recreational soccer (SOC) compared to moderate-intensity continuous running (RUN) on all health-related physical fitness components in healthy untrained men. Sixty-nine participants were recruited and randomly assigned to one of three groups, of which sixty-four completed the study: a soccer training group (SOC; n = 20, 34±4 (means±SD) years, 78.1±8.3 kg, 179±4 cm); a running group (RUN; n = 21, 32±4 years, 78.0±5.5 kg, 179±7 cm); or a passive control group (CON; n = 23, 30±3 years, 76.6±12.0 kg, 178±8 cm). The training intervention lasted 12 weeks and consisted of three 60-min sessions per week. All participants were tested for each of the following physical fitness components: maximal aerobic power, minute ventilation, maximal heart rate, squat jump (SJ), countermovement jump with arm swing (CMJ), sit-and-reach flexibility, and body composition. Over the 12 weeks, VO2max relative to body weight increased more (p<0.05) in SOC (24.2%, ES = 1.20) and RUN (21.5%, ES = 1.17) than in CON (-5.0%, ES = -0.24), partly due to large changes in body mass (-5.9, -5.7 and +2.6 kg, p<0.05 for SOC, RUN and CON, respectively). Over the 12 weeks, SJ and CMJ performance increased more (p<0.05) in SOC (14.8 and 12.1%, ES = 1.08 and 0.81) than in RUN (3.3 and 3.0%, ES = 0.23 and 0.19) and CON (0.3 and 0.2%), while flexibility also increased more (p<0.05) in SOC (94%, ES = 0.97) than in RUN and CON (0-2%). In conclusion, untrained men displayed marked improvements in maximal aerobic power after 12 weeks of soccer training and moderate-intensity running, partly due to large decreases in body mass. Additionally soccer training induced pronounced positive effects on jump performance and flexibility, making soccer an effective broad-spectrum fitness training intervention.


#5 Longitudinal development of match-running performance in elite male youth soccer players
Reference: Scand J Med Sci Sports. 2015 Aug 24. doi: 10.1111/sms.12534. [Epub ahead of print]
Authors: Saward C, Morris JG, Nevill ME, Nevill AM, Sunderland C
Summary: This study longitudinally examined age-related changes in the match-running performance of retained and released elite youth soccer players aged 8-18 years. The effect of playing position on age-related changes was also considered. Across three seasons, 263 elite youth soccer players were assessed in 1-29 competitive matches (988 player-matches). For each player-match, total distance and distances covered at age group-specific speed zones (low-speed, high-speed, sprinting) were calculated using 1 Hz or 5 Hz GPS. Mixed modeling predicted that match-running performance developed nonlinearly, with age-related changes best described with quadratic age terms. Modeling predicted that playing position significantly modified age-related changes (P < 0.05) and retained players covered significantly more low-speed distance compared with released players (P < 0.05), by 75 ± 71 m/h (mean ± 95% CI; effect size ± 95% CI: 0.35 ± 0.34). Model intercepts randomly varied, indicating differences between players in match-running performance unexplained by age, playing position or status. These findings may assist experts in developing training programs specific to the match play demands of players of different ages and playing positions. Although retained players covered more low-speed distance than released players, further study of the actions comprising low-speed distance during match play is warranted to better understand factors differentiating retained and released players.


#6 Talented football players' development of achievement motives, volitional components, and self-referential cognitions: A longitudinal study
Reference: Eur J Sport Sci. 2015 Aug 27:1-9. [Epub ahead of print]
Authors: Feichtinger P, Höner O
Download link: http://www.plosone.org/article/fetchObject.action?uri=info:doi/10.1371/journal.pone.0136503&representation=PDF
Summary: Adolescence is regarded as a key developmental phase in the course of talented football players' careers. The present study focuses on early adolescent players' development of achievement motives, volitional components, and self-referential cognitions. Based on the multidimensional and dynamic nature of talent, the development of multifaceted personality characteristics is an important issue in the context of sports talent research. According to previous findings in psychology, personality characteristics' development is defined by both stability and change, and the current study analyses four different types: differential stability (I), mean-level change (II), individual-level change (III), and structural stability (IV). The sample consists of 151 male players in the talent development programme of the German Football Association. Psychological diagnostics of the personality characteristics are implemented across longitudinal sections over a time period of three seasons, from the U12 to U14 age classes. The results reveal that the personality characteristics show (I) moderate test-retest correlations over one-year intervals (.43 ≤ rtt ≤ .62), and lower coefficients for a two-year period (.26 ≤ rtt  ≤ .53). (II) Most of the personality characteristics' mean values differ significantly across the age classes with small effect sizes (.01 ≤ [Formula: see text] ≤ .03). (III) Only minor individual-level changes in the football players' development are found. (IV) The personality characteristics' associations within a two-factor structure do not stay invariant over time. From the results of the present study, conclusions are drawn regarding the talent identification and development process.


#7 Changes in postural control between 13- and 19-year-old soccer players: is there a need for a specific therapy?
Reference: J Phys Ther Sci. 2015 Aug;27(8):2555-7. doi: 10.1589/jpts.27.2555. Epub 2015 Aug 21.
Authors: Bieć E, Giemza C, Kuczyński M
Summary: The purpose was to investigate how increased training participation time and intensity affect postural control in young soccer players. Variability and mean velocity of sway were compared in U14 and U20 players during two-legged and one-legged quiet stances on a force plate with the player's eyes open or closed. U20 players performed much better with vision, and eyes closure considerably deteriorated their performance. The increased reliance on vision in the older group most likely resulted from the longer exposure of the U20 players to strenuous exercise, overload, and cumulative residual effects of earlier contusions. These specific postural deficits in apparently healthy soccer players were found only because of objective and sensitive posturographic tests. The results of this study suggest that such tests should be regularly performed to increase the efficiency and precision of motor control evaluation in athletes. The corresponding results may help therapists mitigate the indiscernible yet detrimental changes in postural control that predispose soccer players to injury and negatively affect their performance.


#8  Changes in postural control between 13- and 19-year-old soccer players: is there a need for a specific therapy?
Reference: J Phys Ther Sci. 2015 Aug;27(8):2555-7. doi: 10.1589/jpts.27.2555. Epub 2015 Aug 21.
Authors: Bieć E, Giemza C, Kuczyński M
Summary: The purpose of the study was to investigate how increased training participation time and intensity affect postural control in young soccer players. Variability and mean velocity of sway were compared in U14 and U20 players during two-legged and one-legged quiet stances on a force plate with the player's eyes open or closed. U20 players performed much better with vision, and eyes closure considerably deteriorated their performance. The increased reliance on vision in the older group most likely resulted from the longer exposure of the U20 players to strenuous exercise, overload, and cumulative residual effects of earlier contusions. These specific postural deficits in apparently healthy soccer players were found only because of objective and sensitive posturographic tests. The results of this study suggest that such tests should be regularly performed to increase the efficiency and precision of motor control evaluation in athletes. The corresponding results may help therapists mitigate the indiscernible yet detrimental changes in postural control that predispose soccer players to injury and negatively affect their performance.


#9 Game demands of 7-a-side soccer in young players
Reference: J Strength Cond Res. 2015 Sep 1. [Epub ahead of print]
Authors: Barbero-Alvarez JC, López MG, Castagna C, Barbero-Alvarez V, Romero DV, Blanchfield AW, Nakamura FY.
Summary: The aim of this study was to examine the activity patterns and physiological demands of 7-a-side youth soccer matches across two chronological age categories (U12 and U14). Twenty-two soccer players of a national youth soccer academy were investigated. Players of each age category performed two training match (2 x 25 min) and were monitored by GPS and heart rate monitor units. Players of both categories covered similar total distance (5348 ± 307 m), at similar mean heart rate values (86 ± 4% of maximum). However, the number of high-intensity runs (82.5 ± 17.4 vs. 69.7 ± 15.2) and total distance covered during sprints (264 ± 207 vs. 128 ± 74 m) were significantly (p<0.05) higher in U14 compared with U12. The results suggest a highly demanding nature of 7-a-side soccer for skilled players, with physical maturity possibly influencing the match related high intensity performance at these ages.


#10 The Power of a Soccer Ball: A Traumatic Open Finger Dislocation-A Rare Case Presentation
Reference: Case Rep Orthop. 2015;2015:698928. doi: 10.1155/2015/698928. Epub 2015 Aug 16.
Authors: Dülgeroğlu TC, Metineren H, Aydın E, Dülgeroğlu A
Download link: downloads.hindawi.com/journals/crior/2015/698928.pdf
Summary: Proximal interphalangeal joint dislocations are injuries observed frequently and caused by axial loading on the finger in the extension. In this paper we present a traumatic open finger dislocation due to a ball hitting a wrestler. It was successfully treated with reduction and the volar plate and collateral bond fixation were applied with absorbable sutures.