13 research outputs found
Exercise-Based Training Strategies to Reduce the Incidence or Mitigate the Risk Factors of Anterior Cruciate Ligament Injury in Adult Football (Soccer) Players: A Systematic Review
Anterior cruciate ligament (ACL) is one of the most concerning injuries for football players.
The aim of this review is to investigate the effects of exercise-based interventions targeting at reducing
ACL injury rate or mitigating risk factors of ACL injury in adult football players. Following PRISMA
guidelines, a systematic search was conducted in CINAHL, Cochrane Library, PubMed, Scopus,
SPORTDiscus and Web of Science. Studies assessing the effect of exercise-based interventions in
ACL injury incidence or modifiable risk factors in adult football players were included. 29 studies
evaluating 4502 male and 1589 female players were included (15 RCT, 8 NRCT, 6 single-arm):
14 included warm-up, 7 resistance training, 4 mixed training, 3 balance, 1 core stability and 1 technique
modification interventions. 6 out of 29 studies investigated the effect of interventions on ACL injury
incidence, while the remaining 23 investigated their effect on risk factors. Only 21% and 13% studies
evaluating risk of injury variables reported reliability measures and/or smallest worthwhile change
data. Warm-up, core stability, balance and technique modification appear effective and feasible
interventions to be included in football teams. However, the use of more ecologically valid tests and
individually tailored interventions targeting specific ACL injury mechanisms are required
How does curve sprint evolve across different age categories in soccer players?
: Research has shown that soccer players regularly execute curved sprints during matches. The
purpose of this study was to determine the age-related effects on curve sprint (CS) performance to both sides,
asymmetry, and association with linear sprint (LS). Eighty-four soccer players (aged 16.1 ± 1.6 categorized in
U15, U17, and U20) were recruited, who performed CS and LS tests. One-way analysis of variance (ANOVA)
and effect size (ES) were used to compare CS performance between age categories, and relationships between
physical performance measures were calculated using Pearson’s correlation coefficient. The main findings of
this study were that: 1) there were significant differences in the “good” side CS among age groups (p < 0.001;
ES from moderate to large), but not in the “weak” side CS, 2) curve asymmetry was significantly higher in U20
than U15 (p < 0.05; ES large) and U17 players (p < 0.05; ES moderate), and 3) relationships between CS and
LS times decreased with age (from significant and very large [p 0.05]). This study highlights the importance of assessing and training CS in different age
categories, an action that becomes less correlated with LS as age increases, with the aim of mitigating the
increase in asymmetries as a result of the specialization process, focusing interventions mainly on improving the CS “weak” sideThanks to all the participants in this study, to Football Science Institute, and to the soccer clu
a living systematic review
Background: Hamstrings injuries are common in sports and the reinjury risk is high. Despite the extensive literature on hamstrings injuries, the efectiveness of the diferent conservative (i.e., non-surgical) interventions (i.e., modalities and doses) for the rehabilitation of athletes with acute hamstrings injuries is unclear.
Objective: We aimed to compare the efects of diferent conservative interventions in time to return to sport (TRTS) and/or time to return to full training (TRFT) and reinjury-related outcomes after acute hamstrings injuries in athletes. Data Sources: We searched CINAHL, Cochrane Library, EMBASE, PubMed, Scopus, SPORTDiscus, and Web of Science databases up to 1 January, 2022, complemented with manual searches, prospective citation tracking, and consultation of external experts. Eligibility Criteria: the eligibility criteria were multi-arm studies (randomized and non-randomized) that compared conservative treatments of acute hamstrings injuries in athletes. Data Analysis: We summarized the characteristics of included studies and conservative interventions and analyzed data for main outcomes (TRTS, TRFT, and rate of reinjuries). The risk of bias was judged using the Cochrane tools. Quality and completeness of reporting of therapeutic exercise programs were appraised with the i-CONTENT tool and the certainty of evidence was judged using the GRADE framework. TRTS and TRFT were analyzed using mean diferences and the risk of reinjury with relative risks.
Results Fourteen studies (12 randomized and two non-randomized) comprising 730 athletes (mostly men with ages between 14 and 49 years) from diferent sports were included. Nine randomized studies were judged at high risk and three at low risk of bias, and the two non-randomized studies were judged at critical risk of bias. Seven randomized studies compared exercise-based interventions (e.g., L-protocol vs C-protocol), one randomized study compared the use of low-level laser therapy, and three randomized and two non-randomized studies compared injections of platelet-rich plasma to placebo or no injection. These low-level laser therapy and platelet-rich plasma studies complemented their interventions with an exercise program. Only three studies were judged at low overall risk of inefectiveness (i-CONTENT). No single intervention or combination of interventions proved superior in achieving a faster TRTS/TRFT or reducing the risk of reinjury. Only eccentric lengthening exercises showed limited evidence in allowing a shorter TRFT. The platelet-rich plasma treatment did not consistently reduce the TRFT or have any efect on the risk of new hamstrings injuries. The certainty of evidence was very low for all outcomes and comparisons.
Conclusions: Available evidence precludes the prioritization of a particular exercise-based intervention for athletes with acute hamstrings injuries, as diferent exercise-based interventions showed comparable efects on TRTS/TRFT and the risk of reinjuries. Available evidence also does not support the use of platelet-rich plasma or low-level laser therapy in clinical practice. The currently available literature is limited because of the risk of bias, risk of inefectiveness of exercise protocols (as assessed with the i-CONTENT), and the lack of comparability across existing studies. Clinical Trial Registration PROSPERO CRD42021268499 and OSF (https://osf.io/3k4u2/).9513-E3E4-C5C9 | Sílvia Fernanda Rocha RodriguesN/
Exercise-Based Training Strategies to Reduce the Incidence or Mitigate the Risk Factors of Anterior Cruciate Ligament Injury in Adult Football (Soccer) Players: A Systematic Review
Anterior cruciate ligament (ACL) is one of the most concerning injuries for football players. The aim of this review is to investigate the effects of exercise-based interventions targeting at reducing ACL injury rate or mitigating risk factors of ACL injury in adult football players. Following PRISMA guidelines, a systematic search was conducted in CINAHL, Cochrane Library, PubMed, Scopus, SPORTDiscus and Web of Science. Studies assessing the effect of exercise-based interventions in ACL injury incidence or modifiable risk factors in adult football players were included. 29 studies evaluating 4502 male and 1589 female players were included (15 RCT, 8 NRCT, 6 single-arm): 14 included warm-up, 7 resistance training, 4 mixed training, 3 balance, 1 core stability and 1 technique modification interventions. 6 out of 29 studies investigated the effect of interventions on ACL injury incidence, while the remaining 23 investigated their effect on risk factors. Only 21% and 13% studies evaluating risk of injury variables reported reliability measures and/or smallest worthwhile change data. Warm-up, core stability, balance and technique modification appear effective and feasible interventions to be included in football teams. However, the use of more ecologically valid tests and individually tailored interventions targeting specific ACL injury mechanisms are required.</jats:p
Exercise-Based Training Strategies to Reduce the Incidence or Mitigate the Risk Factors of Anterior Cruciate Ligament Injury in Adult Football (Soccer) Players: A Systematic Review
Anterior cruciate ligament (ACL) is one of the most concerning injuries for football players. The aim of this review is to investigate the effects of exercise-based interventions targeting at reducing ACL injury rate or mitigating risk factors of ACL injury in adult football players. Following PRISMA guidelines, a systematic search was conducted in CINAHL, Cochrane Library, PubMed, Scopus, SPORTDiscus and Web of Science. Studies assessing the effect of exercise-based interventions in ACL injury incidence or modifiable risk factors in adult football players were included. 29 studies evaluating 4502 male and 1589 female players were included (15 RCT, 8 NRCT, 6 single-arm): 14 included warm-up, 7 resistance training, 4 mixed training, 3 balance, 1 core stability and 1 technique modification interventions. 6 out of 29 studies investigated the effect of interventions on ACL injury incidence, while the remaining 23 investigated their effect on risk factors. Only 21% and 13% studies evaluating risk of injury variables reported reliability measures and/or smallest worthwhile change data. Warm-up, core stability, balance and technique modification appear effective and feasible interventions to be included in football teams. However, the use of more ecologically valid tests and individually tailored interventions targeting specific ACL injury mechanisms are required
Prevención de lesión de ligamento cruzado anterior en futbolistas: protocolo de campo e intervenciones eficientes
La lesión de ligamento cruzado anterior (LCA) es una de las que mayor preocupación
genera. A nivel de club, porque supone perder un jugador para el resto de temporada, con
sus correspondientes implicaciones económicas y de rendimiento. A nivel de jugador, por
sus devastadores consecuencias, como el riesgo acrecentado de sufrir una segunda lesión,
de no volver a competir al nivel previo o de sufrir osteoartritis temprana. La lesión de
LCA ocurre principalmente en mecanismos de no contacto o contacto indirecto con la
pierna lesionada (80%), comúnmente al realizar maniobras de cambio de dirección
(CDD) o aterrizaje de salto en situaciones defensivas, con incertidumbre. Se han asociado
muchos factores de riesgo a la lesión de LCA, aunque ninguno de forma contundente por
las limitaciones metodológicas de los diseños de investigación utilizados. Se han
propuesto multitud de programas de intervención para su prevención, si bien pocos han
considerado el contexto característico del fútbol, lo que se ha traducido en una muy baja
implementación de dichos programas.
El objetivo general de la tesis fue diseñar un protocolo integral de campo dirigido a
evaluar los factores de riesgo de lesión de LCA en futbolistas, así como a mitigarlos
mediante estrategias preventivas fácilmente aplicables, considerando las frecuentes
limitaciones de equipamiento, espacio y tiempo presentes en el contexto de un equipo de
fútbol. El objetivo se abordó mediante cuatro artículos, tres de ellos publicados (artículos
2, 3 y 4) en revistas indexadas en el Journal of Scitation Reports.
Artículo 1. Mediante esta revisión sistemática se pretendió encontrar todas aquellos test
que, mediante maniobras de aterrizaje y CDD, trataran de evaluar los riesgos de jugadores
de fútbol de sufrir una lesión de LCA. Se halló que existen una gran variedad de test con
dicho propósito tanto para aterrizajes (i.e. saltos con y sin contramovimiento, drop
landings, drop jumps (DVJ), saltos con carrera de aproximación, saltos horizontales y
consecutivos) como para CDD (i.e. de angulación leve, moderada y agresiva), aunque
pocos se han asociado apropiadamente a la lesión de LCA y donde raramente se han
ofrecido los niveles de fiabilidad de las métricas evaluadas.
Artículo 2. El objetivo de la segunda revisión sistemática fue el de recopilar todas
aquellas intervenciones basadas en ejercicio físico, de más de 4 semanas, diseñadas para
reducir la incidencia o los riesgos de lesión de LCA en futbolistas adultos. Se encontró
que algunos programas de calentamiento, como el “FIFA 11+” o el “PEP Program” se
han mostrado eficaces para la reducción de la incidencia, aunque los mecanismos
mediante los que lo consiguen no están claros. Otras intervenciones basadas en
modificación técnica, trabajo lumbopélvico y equilibrio mostraron efectos prometedores,
con programas de entrenamiento resistido revelándose eficaces, aunque difícilmente
implementables en el contexto de un equipo de fútbol. Destaca la escasez de
intervenciones que fueron evaluadas por su capacidad para reducir los riesgos asociados
a los principales mecanismos de lesión de LCA, así como la escasa, cuando no ausente
descripción de los programas y test utilizados (i.e. niveles de fiabilidad y supervisores de la intervención no reportados, poca claridad en los métodos o enfoques estadísticos
inapropiados).
Artículo 3. En este artículo transversal se evaluó a 42 futbolistas semiprofesionales con
el objetivo de determinar si las escalas Landing Error Scoring System (LESS) y Cutting
Movement Assessment Score (CMAS) para valorar la calidad de movimiento de DVJ y
CDD, respectivamente, son fiables en este cohorte de futbolistas, además de dilucidar si
aportan un perfil de riesgo compartido. Los resultados demostraron que ambas poseen
niveles de moderados a sustanciales de fiabilidad interobservador (ICC = 0.58-0.71) y de
sustanciales a casi perfectos de fiabilidad intraobservador (ICC = 0.68-0.87). Además, no
se encontró relación alguna entre el perfil de riesgo obtenido para una y otra escala, lo
que sugiere que el riesgo para sufrir una lesión de LCA es dependiente de la tarea. El
segundo aterrizaje del DVJ manifestó peores niveles de calidad de movimiento que el
primero (ES = 0.80-0.83) justificando así el uso de ambos, junto al CMAS, para una
panorámica más detallada del perfil de riesgo del jugador.
Artículo 4. En el último artículo se evaluó la capacidad del Safe Landing, un programa
de intervención basado en aterrizajes, pliometría y CDD con un énfasis en la corrección
técnica, llevado a cabo durante 6 semanas, 3 veces por semana e incluido como parte del
calentamiento para mejorar la calidad de movimiento del DVJ y el CDD, evaluadas
mediante las escalas LESS y CMAS. El grupo experimental (GE, n = 15) mostró mejoras
de magnitudes moderadas a grandes en ambos aterrizajes del DVJ (LESS1 y LESS2) y
en el CMAS (p < 0.082, ղ2 = 0.137–0.272) respecto del grupo control (GC, n = 11), sin
una merma en el rendimiento en dichas maniobras, que se mantuvo estable antes y
después de la intervención (p > 0.05, ES = 0.039–0.420). Dado el escaso equipamiento
(i.e. conos y balones) y el poco tiempo necesario para su implementación (~ 9 minutos /
sesión), el Safe Landing se propone como una intervención efectiva y fácilmente
implementable (con una adherencia superior al 93%) para mejorar la calidad de
movimiento de jugadores de fútbol semiprofesionales.
Asimismo, mediante la presente tesis doctoral se proporcionaron herramientas válidas y
fiables para la identificación de riesgos de lesión de LCA en sus principales mecanismos
predisponentes a profesionales médicos y de rendimiento, así como estrategias eficientes
para la reducción efectiva de dichos riesgos. Un proceso que se abordó intentando
mantener un equilibrio entre la rigurosidad metodológica que exige el método científico
y la realidad contextual que caracteriza a equipos de fútbol.The anterior cruciate ligament (ACL) injury is one of the most concerning. At the club
level, because it leads to lose a player for the rest of the season, with its corresponding
economic and performance implications. At the player level, due to its devastating
consequences, such as the increased risk of suffering a second injury, not being able to
compete at the previous level, or suffering early osteoarthritis. ACL injuries mainly occur
in non-contact or indirect contact mechanisms with the injured leg (80%), commonly
when performing either change of direction (COD) manoeuvres or landings from a jump
in defensive situations, under uncertainty. Many risk factors have been related to ACL
injury, although usually through weak associations due to the methodological limitations
of the research designs traditionally used. Numerous intervention programs have been
proposed for its prevention, although few have considered the characteristic context of
football, resulting in very low implementation levels of such programs.
The general aim of the thesis was to develop a comprehensive protocol to both evaluating
the risk factors of ACL injuries of football players, as well as mitigating them through
easily implementable preventative programs. For that purpose, the equipment, space and
time restrictions frequently observed in football teams was always considered. To achieve
the aim four scientific articles were carried out, of which 3 were published (articles 2, 3
and 4) in journals indexed in the Journal of Citation Reports.
Article 1. Through this systematic review, we aimed to find all those tests that were
developed to assess the risks of football players suffering an ACL injury through either
landing or cutting manoeuvres. It was found that there is a wide variety of tests for this
purpose both for landings (i.e. jumps with and without countermovement, drop landings,
drop jumps (DVJ), running approach jumps, horizontal and consecutive jumps) and
cuttings (i.e. of shallow, moderate, and sharp angulations), although very few have been
appropriately associated with ACL injury, and where the levels of reliability of the
metrics evaluated have rarely been offered.
Article 2. The aim of the second systematic review was to compile all those exercisebased
interventions, lasting more than 4 weeks, that were designed to reduce the incidence
or risks of ACL injury in adult footballers. It was found that some warm-up programs,
such as “FIFA 11+” or the “PEP Program” were effective in reducing the incidence,
although the mechanisms by which they achieved this reduction are not clear. Other
interventions based on technical modification, lumbopelvic strengthening, and balance
showed promising effects, with resistance training programs proving effective, although
difficult to implement in a football team context. Noteworthy is the scarcity of
interventions evaluated for their ability to reduce the risks associated with the main ACL
injury mechanisms, as well as the scarce and/or poor description of the programs and tests
used (i.e., levels of reliability and supervisors of the intervention not reported, lack of
clarity in the methods or inappropriate statistical approaches). Article 3. In this cross-sectional article, 42 semi-professional footballers were evaluated
to determine if the Landing Error Scoring System (LESS) and Cutting Movement
Assessment Score (CMAS) scales are reliable for assessing the quality of movement in
DVJ and COD, respectively, as well as to elucidate whether they provide a shared ACL
risk profile of the players. The results showed that they possess moderate to substantial
levels of intra-observer reliability (ICC = 0.58-0.71), and substantial to almost perfect
inter-observer reliability (ICC = 0.68-0.87). In addition, no relationship was found
between the risk profile obtained for one scale and the other, suggesting that the risk of
suffering an ACL injury is task-dependent. The second landing of the DVJ (LESS2)
displayed a riskier pattern than the first (LESS1) (ES = 0.80-0.83) justifying the use of
both, along with the CMAS, for a more detailed overview of the player's risk profile.
Article 4. In the last article, the capability of the Safe Landing, a technique-modification
intervention based on landings, plyometrics, and COD exercises, to improve the
movement quality of DVJ and COD was evaluated through the LESS and CMAS scales.
It was carried out for 6 weeks, 3 times a week, and included as part of the warm-up. The
experimental group (EG, n = 15) showed moderate to large improvements in both
landings of the DVJ (LESS1 and LESS2) and in the CMAS (p < 0.082, ղ2 = 0.137–0.272)
compared to the control group (CG, n = 11), without a decline in performance in such
manoeuvres, which remained stable pre- to post-intervention (p > 0.05, ES = 0.039–
0.420). Given the little equipment (i.e., cones and balls), and the short time required for
its implementation (~9 minutes/session), the Safe Landing is proposed as an effective and
easily implementable intervention (with compliance levels above 93%) to improve the
movement quality of semi-professional football players.
By this way, through this doctoral thesis, practitioners working in medical and
performance staffs were provided by valid and reliable screening tools for the
identification of their football players’ injury risk in the main mechanisms predisposing
to ACL injury, as well as by efficient strategies for the effective reduction of these risks.
To properly address the process, the approach was based on an attempt to keep a balance
between the methodological rigor required by the scientific method and the reality that
characterises the football’s context.Tesis Univ. Granada.HumanLabInstituto Universitario Deporte y Salud (iMUDS)Football Science Institute (FSI
Curve sprinting in Soccer: Kinematic and Neuromuscular Analysis
Sprinting in curvilinear trajectories is an important soccer ability,
corresponding to ~85 % of the actions performed at maximum
velocity in a soccer league. We compared the neuromuscular
behavior and foot contact-time between outside leg and
inside leg during curve sprinting to both sides in soccer players.
Nine soccer players (age = 23 ± 4.12 years) performed: 3 × Sprint
linear, 3 × Sprint right curve, and 3 × Sprint left curve. An ANOVA
with repeated measures was used to compare the differences
between inside and outside leg, and Cohen’s d was used
to calculate the effect-size. Considering the average data, the
performance classification (from best to worst) was as follows:
1. Curve “good” side (2.45 ± 0.11 s), 2. Linear (2.47 ± 0.13 s),
and 3. Curve “weak” side (2.56 ± 0.17 s). Comparing linear with
curve sprinting, inside leg recorded significant differences
(“good” and “weak”; effect size = 1.20 and 2, respectively); in
contrast, for outside leg, there were no significant differences
(“good” and “weak”; effect size = 0.30 and 0.49, respectively).
Electromyography activity showed significant differences
(p ≤ 0.05) during curve sprinting between outside (higher in
biceps femoris and gluteus medius) and inside leg (higher activity
in semitendinosus and adductor). In summary, inside and
outside leg play different roles during curved sprints, but inside
leg is more affected by the change from straight to curve sprint
The Safe Landing warm up technique modification programme: An effective anterior cruciate ligament injury mitigation strategy to improve cutting and jump-movement quality in soccer players
The objective of the study was to evaluate the effectiveness of the Safe Landing (SL), a 6-week technique-modification (TM) programme, on cutting and jump-landing movement quality in football players. In a non-randomized design, 32 male semi-professional football players from two Spanish clubs participated in the study: one served as the control group (CG, n = 11), while the other performed the SL (n = 15). Performance and movement quality of drop vertical jump and 70º change of direction (COD70) were evaluated through 2D video footage pre- and post-intervention. In such tasks, the Landing Error Scoring System for first (LESS1) and second (LESS2) landings, and the Cutting Movement Assessment Score (CMAS) were used for assessing movement quality. Pre-to-post changes and baseline-adjusted ANCOVA were used. Medium-to-large differences between groups at post-test were shown in CMAS, LESS1 and LESS2 (p 0.05) pre-to-post. In COD70 performance, large differences were found between groups (p 0.05, ES=0.039–0.420), while CG moderately decreasing performance (p = 0.024, ES=0.753) pre-to-post. The SL is a feasible and effective TM program to improve movement quality and thus potential injury risk in cutting and landing, while not negatively affecting performance
High-intensity actions in elite soccer: current status and future perspectives
Over the years, soccer has become more physically demanding; the number and frequency of high-intensity actions have increased, and these activities are decisive in determining the match outcome. Importantly, the reductionist approach commonly used to analyze high-intensity actions does not contemplate a more contextualized perspective on soccer performance. Traditionally, most investigations have only provided quantitative data regarding sprints (i. e. time, distances, frequency) without examining "how" (e. g. type of trajectory or starting position) and "why" (e. g. tactical role) soccer players sprint. In fact, other high-intensity actions, apart from running, are not even mentioned (i. e. curve sprints, change of direction, and specific-jump tasks). This has led to the use of tests and interventions that do not accurately reflect real game actions. Given the true technical-tactical-physical demands of each playing position, this narrative review collected a wide-spectrum of current soccer-related articles and provided a discussion regarding high-intensity actions, with a positional-based approach. In this narrative review, practitioners are encouraged to contemplate and consider the different elements that characterize high-intensity actions in soccer, in order to assess and train soccer players under a more sport-specific and integrative perspective
Effect of Ball Inclusion on Jump Performance in Soccer Players: A Biomechanical Approach
Objective: In soccer, vertical jump means jumping toward a ball. Since no vertical jump test includes the ball as a reference element, the effect that the ball would have in a vertical jump test is unknown. The aim of this study was to examine the biomechanical differences between run-up vertical jump measurements without (Run-up Vertical Jump) and with ball inclusion (Heading Test). Methods: Twelve semi- and professional soccer players were recruited. Athletes performed both jump tests in a biomechanical laboratory, where kinetic and spatiotemporal variables were collected and compared using a Student’s dependent t-test for paired samples. Results: Overall, players performed a different jumping strategy during the heading test compared to the run-up vertical jump, exhibiting: 1) higher horizontal velocity during initial contact (+45.3%, P ≤ .001), 2) shorter contact time, greater rate of force development, and total impulse during push-off (+27.5%, +53%, and +10.6%, respectively, P ≤ .008), 3) higher CoM horizontal and resultant velocity during take-off (+76.1% and 20.5%, respectively, P ≤ .001), 4) better vertical jump performance (+4.3%, P ≤ .0001), and 5) larger body angle rotation during landing (+63.3%, P = .006), compared to run-up vertical jump (effect size: 0.78 to 3.7). Conclusion: In general, soccer players display greater vertical jump heights in heading test, which highlights the importance of including an overhead ball during soccer-specific jump tests. Coaches and practitioners are encouraged to assess, and perhaps develop, the jumping ability of soccer players using a suspended ball as a specific target