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BACKGROUND: There is substantial evidence exploring the reliability of running distance self-reporting and GPS wearable technology, but there are currently no studies investigating the reliability of participant self-reporting in comparison to GPS wearable technology. There is also a critical sports science and medical research gap due to a paucity of reliability studies assessing self-reported running pace. OBJECTIVE: The purpose of this study was to assess the reliability of weekly self-reported running distance and pace compared to a commercial GPS fitness watch, stratified by sex and age. These data will give clinicians and sports researchers insights into the reliability of runners' self-reported pace, which may improve training designs and rehabilitation prescriptions. METHODS: A prospective study of recreational runners was performed. Weekly running distance and average running pace were captured through self-report and a fitness watch. Baseline characteristics collected included age and sex. Intraclass correlational coefficients were calculated for weekly running distance and running pace for self-report and watch data. Bland-Altman plots assessed any systemic measurement error. Analyses were then stratified by sex and age. RESULTS: Younger runners reported improved weekly distance reliability (median 0.93, IQR 0.92-0.94). All ages demonstrated similar running pace reliability. Results exhibited no discernable systematic bias. CONCLUSIONS: Weekly self-report demonstrated good reliability for running distance and moderate reliability for running pace in comparison to the watch data. Similar reliability was observed for male and female participants. Younger runners demonstrated improved running distance reliability, but all age groups exhibited similar pace reliability. Running pace potentially should be monitored through technological means to increase precision.
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Background: Breakdancing or breaking will enter the Olympics in 2024, however, there is a paucity of literature exploring the epidemiology, demands, and performance. Purpose: The purpose of this study was to describe injury and training profiles, along with the results of a short performance test battery, in a group of elite breakers. Study Design: Cross-sectional study (retrospective). Methods: Fourteen breakdancers (breakers) (4 Bgirls, 10 Bboys) participated in an interview regarding their injury and training history, endurance test (cycle VO2max testing), counter movement jump, squat jump, drop jump, isometric hip abduction, adduction, shoulder external and internal rotation strength testing on a fixed-frame dynamometer. Breakers were divided into elite (n=10) and developing (n=4) based on their qualification for a world finals competition; Wilcoxen rank sums were used to compare the two groups, or in the case of strength testing between those with and without an injury history. Results: The breakers had a median 11.0 [10.0 - 14.0] years breaking experience and trained 24.4 [20.5 - 30.0] hours per week. The knee was the most commonly injured body part and most frequently injured joint, with the thigh being the most common site for muscle injuries. There were no differences in endurance testing or jump height testing results between elite and developing breakers. There was no difference in shoulder external or internal rotation strength between athletes with a history of shoulder injury and those without. Similarly, there was no difference in hip abduction or adduction strength in those with a history of hip injury and those without. Conclusion: The results of this study should be viewed with caution due to the small sample size. However, this study is the first to publish functional and physiological descriptives on breakers. The authors hope these results support clinicians treating breakers as well as encourages future research related to breaking. Level of Evidence: 2b.
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Background: The 11+ injury prevention program (IPP) has been shown to decrease injury rates. However, few studies have investigated compliance and its overall relationship to team performance. Hypothesis/Purpose: To examine if level of compliance while implementing the 11+ would impact team performance outcomes (wins, losses and ties). The authors hypothesized that higher team compliance to the IPP would be consistent with improved overall team performance (more wins and fewer losses). Study Design: Prospective, cluster randomized controlled trial. Methods: This study was conducted in NCAA men's soccer teams for one season and examined the efficacy of the 11+ IPP. The outcome variables examined were levels of compliance and team performance record: wins, losses, and ties. Twenty-seven teams (n=675 players) served as the intervention group (IG) and used the 11+ program while 34 teams (n=850 players) served as the control group (CG). Compliance and team performance were recorded. There were three compliance categories that were defined prospectively, low (LC, < 1 dose/week), moderate (MC, >1 and <2 doses/week), and high (HC, >2 doses/week). Descriptive and inferential tests were used to compare the CG, the IG, and compliance to team performance. Three independent t-tests were used to analyze outcome to group (IG vs. CG). A one way-MANOVA test was used to analyze compliance to win/loss/tie record, followed up by one-way ANOVA tests to analyze how compliance impacted wins, losses and ties, independently. Partial η2 measures were calculated to determine the effect size of level of compliance on outcome. A Tukey post-hoc analysis was used to analyze specific differences between levels of compliance and specific outcome measures. Results: There were significantly more wins (IG: 10.67±2.63 versus CG: 8.15±3.83, CI, 7.95 - 9.69, p = 0.005) and fewer losses (IG: 5.56±1.97 versus CG: 8.12±3.59, CI, 5.66 to 7.43, p = 0.002) recorded for the teams using the 11+ program. There was a statistically significant difference between levels of compliance (high, moderate or low) on the dependent variables (wins, losses, and ties), F(3, 22) = 3.780, p =0.004; Wilks' Λ = .435; partial η2 = .340. Conclusion: The 11+ has the capacity to improve overall team performance in male collegiate soccer teams. The higher the compliance, the more favorable the team performance. This research may be a vital addition when attempting to persuade coaching staffs to adopt an IPP into their training regimen. Level of Evidence: Level I.
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SYNOPSIS: Researchers often assign a label (such as a risk factor or predictor) to a characteristic that is statistically associated with an outcome (such as future injury). Labeling signifies that the characteristic has an established clinical value. More often than not, these labels are assigned prematurely and haphazardly. The rampant practice conflates research goals, the ultimate clinical value of the findings, and many risk factors/predictors that may not warrant the label. To address these issues and improve injury prevention research, we (1) outline the problem; (2) clarify the key differences between the research goals of description, causation, and prediction/prognosis (along with labeling conventions); (3) differentiate the clinical implications for each label; and (4) frame an appropriate scientific process to follow before applying a label. J Orthop Sports Phys Ther 2023;53(7):1-7. Epub: 26 April 2023. doi:10.2519/jospt.2023.11773.
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Traumatismos em Atletas , Esportes , Humanos , Traumatismos em Atletas/prevenção & controle , Fatores de Risco , Terapia por Exercício , Exercício FísicoRESUMO
The Academy of Orthopaedic Physical Therapy and the American Academy of Sports Physical Therapy have an ongoing effort to create evidence-based clinical practice guidelines (CPGs) for orthopaedic and sports physical therapy management and prevention of musculoskeletal impairments described in the World Health Organization's International Classification of Functioning, Disability and Health (ICF). This guideline focuses on the exercise-based prevention of knee injuries and provides an update on the 2018 guideline, J Orthop Sports Phys Ther. 2018;48(9):A1-A42. doi:10.2519/jospt.2018.0303 J Orthop Sports Phys Ther. 2023;53(1):CPG1-CPG34. doi:10.2519/jospt.2023.0301.
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Lesões do Ligamento Cruzado Anterior , Traumatismos do Joelho , Esportes , Humanos , Lesões do Ligamento Cruzado Anterior/prevenção & controle , Lesões do Ligamento Cruzado Anterior/reabilitação , Terapia por Exercício , Modalidades de Fisioterapia , Traumatismos do Joelho/terapiaRESUMO
OBJECTIVES: Trunk kinematics can contribute to lower extremity biomechanical risk factors for anterior cruciate ligament (ACL) injury. However, normative trunk kinematics during unilateral athletic tasks in a large population of "healthy" (no history of ACL injury and no known future ACL injury) women's soccer players have not been well-described. This study's purposes were to describe trunk kinematics in a population of 37 healthy collegiate women's soccer players completing a step-down, a deceleration, and a 90° cut, and to provide a reference for normative values. METHODS: A cross-sectional cohort of 37 female soccer players were analysed for this study. Trunk forward flexion and lateral flexion were measured relative to the pelvis, and trunk centre of mass position was measured relative to the proximal tibia. Trunk kinematics were characterized by individual values at key events during the tasks and time-series curves normalized to 100% of the time. RESULTS: Participants demonstrated increasing trunk forward flexion with increasing knee flexion angle, small amounts of increasing ipsilateral trunk flexion with increasing peak knee abduction moment, and trunk centre of mass position that moved medially during the deceleration and cut tasks. Additionally, participants demonstrated peak trunk lateral flexion angles milliseconds before peak knee flexion angle. CONCLUSION: This study provides a reference for identifying aberrant trunk mechanics that may increase the risk for non-contact ACL injury. LEVEL OF EVIDENCE: Level II.
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Lesões do Ligamento Cruzado Anterior , Futebol , Fenômenos Biomecânicos , Estudos Transversais , Feminino , Humanos , Articulação do Joelho , Futebol/lesõesRESUMO
There is growing interest in the role of predictive analytics in sport, where such extensive data collection provides an exciting opportunity for the development and utilisation of prediction models for medical and performance purposes. Clinical prediction models have traditionally been developed using regression-based approaches, although newer machine learning methods are becoming increasingly popular. Machine learning models are considered 'black box'. In parallel with the increase in machine learning, there is also an emergence of proprietary prediction models that have been developed by researchers with the aim of becoming commercially available. Consequently, because of the profitable nature of proprietary systems, developers are often reluctant to transparently report (or make freely available) the development and validation of their prediction algorithms; the term 'black box' also applies to these systems. The lack of transparency and unavailability of algorithms to allow implementation by others of 'black box' approaches is concerning as it prevents independent evaluation of model performance, interpretability, utility, and generalisability prior to implementation within a sports medicine and performance environment. Therefore, in this Current Opinion article, we: (1) critically examine the use of black box prediction methodology and discuss its limited applicability in sport, and (2) argue that black box methods may pose a threat to delivery and development of effective athlete care and, instead, highlight why transparency and collaboration in prediction research and product development are essential to improve the integration of prediction models into sports medicine and performance.
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Medicina Esportiva , Esportes , Algoritmos , Atletas , Humanos , Aprendizado de Máquina , Medicina Esportiva/métodosRESUMO
The purpose of this study was to compare basketball performance markers 1 y prior to initial severe lower extremity injury, including ankle, knee, and hip injuries, to 1 and 2 y following injury during the regular National Basketball Association (NBA) season. Publicly available data were extracted through a reproducible extraction computed programmed process. Eligible participants were NBA players with at least three seasons played between 2008 and 2019, with a time-loss injury reported during the study period. Basketball performance was evaluated for season minutes, points, and rebounds. Prevalence of return to performance and linear regressions were calculated. A total of 285 athletes sustained a severe lower extremity injury. A total of 196 (69%) played for 1 y and 130 (45%) played for 2 y following the injury. A total of 58 (30%) players participated in a similar number of games and 57 (29%) scored similar points 1 y following injury. A total of 48 (37%) participated in a similar number of games and 55 (42%) scored a similar number of points 2 y following injury. Fewer than half of basketball players who suffered a severe lower extremity injury were participating at the NBA level 2 y following injury, with similar findings for groin/hip/thigh, knee, and ankle injuries. Fewer than half of players were performing at previous preinjury levels 2 y following injury. Suffering a severe lower extremity injury may be a prognostic factor that can assist sports medicine professionals to educate and set performance expectations for NBA players.
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Anterior cruciate ligament (ACL) injuries are one of the most common and severe knee injuries across sports. As such, ACL injury prevention has been a focus of research and sports medicine practice for the past three-plus decades. Examining the current research and identifying both clinical strategies and research gaps, the aim of this review is to empower clinicians and researchers with knowledge of where the ACL injury prevention literature is currently and where it is going in the future. This paper examines the mechanism of ACL injury prevention, screening, implementation, compliance, adherence, coronavirus, and areas of future research. Clinical significance: The time lag between research and practical implementation in general healthcare settings can be as long as 17 years; however, athletes playing sports today are unable to wait that long. With effective programs already established, implementation and adherence to these programs is essential. Strategies such as coaching education, increasing awareness of free programs, identifying barriers, and overcoming implementation obstacles through creative collaboration are just a few ways that could help improve both ACL injury prevention implementation and adherence.
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Lesões do Ligamento Cruzado Anterior/prevenção & controle , Traumatismos em Atletas/prevenção & controle , Traumatismos do Joelho/prevenção & controle , Atletas , Humanos , EsportesRESUMO
Importance: There is limited research investigating injury and illness among professional basketball players during their rookie season. By improving the understanding of injury incidence and risk specific to rookie players, sports medicine clinicians may be able to further individualize injury mitigation programs that address the unique needs of rookie players. Objective: To compare incidence and rate ratio (RR) of injury and illness among professional National Basketball Association (NBA) players in their rookie season with veteran players and to explore the association of sustaining an injury rookie season with career longevity. Design, Setting, and Participants: This retrospective cohort study used an online data repository and extracted publicly available data about NBA players between the 2007 and 2008 season to the 2018 and 2019 season. Available data for initial injury and all subsequent injuries were extracted during this time frame. Exposures: Injury and illness based on injury status during the rookie season of professional NBA players. Main Outcomes and Measures: Injury and illness incidence and RR. Association of injury during the rookie season with career longevity was assessed via Poisson regressions. Results: Of the 12 basketball seasons analyzed, 904 NBA players were included (mean [SD] age, 24.6 [3.9] years; body mass index, 24.8 [1.8]). The injury and illness incidence for rookie players was 14.28 per 1000 athlete game exposures (AGEs). Among all body regions, ankle injuries had the greatest injury incidence among players injured during their rookie season (3.17 [95% CI, 3.15-3.19] per 1000 AGEs). Rookie athletes demonstrated higher RR compared with veterans across multiple regions of the body (ankle: 1.32; 95% CI, 1.12 to 1.52; foot/toe: 1.29; 95% CI, 0.97 to 1.61; shoulder/arm/elbow: 1.43; 95% CI, 1.10 to 1.77; head/neck: 1.21; 95% CI, 0.61 to 1.81; concussions: 2.39; 95% CI, 1.89 to 2.90; illness: 1.14; 95% CI, 0.87 to 1.40), and demonstrated a higher rate of initial injuries compared with veteran players (1.41; 95% CI, 1.29 to 1.53). Players who sustained an injury rookie season demonstrated an unadjusted decrease in total seasons played (-0.4 [95% CI, -0.5 to -0.3] log years; P < .001), but this decrease was not observed within adjusted analysis (0.1 [95% CI, -0.1 to 0.2] log years; P = .36). Conclusions and Relevance: In this study, rookie athletes demonstrated the highest injury incidence at the ankle and increased RR across multiple regions. These findings may reflect differences in preseason conditioning or load variables impacting rookie athletes and warrant further investigation. Future research is needed to determine the association of cumulative injury burden vs a singular injury event on career longevity.
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Atletas/estatística & dados numéricos , Traumatismos em Atletas/diagnóstico , Basquetebol/lesões , Fatores de Tempo , Adolescente , Adulto , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/etiologia , Basquetebol/estatística & dados numéricos , Feminino , Humanos , Masculino , Volta ao EsporteRESUMO
BACKGROUND: Valgus collapse and high knee abduction moments have been identified as biomechanical risk factors for ACL injury. It is unknown if participation in the 11+, a previously established, dynamic warm-up that emphasizes biomechanical technique and reduces ACL injury rates, reduces components of valgus collapse during a 90º cut. HYPOTHESIS/PURPOSE: To determine whether participation in the 11+ during a single soccer season reduced peak knee abduction moment and components of valgus collapse during a 90º cut in collegiate female soccer players. STUDY DESIGN: Prospective cohort study. METHODS: Forty-six participants completed preseason and postseason motion analysis of a 90º cut. During the season, 31 players completed the 11+ and 15 players completed their typical warm-up (control group). Peak knee abduction moment, components of valgus collapse (hip adduction, internal rotation, and knee abduction angles), and a novel measure of knee valgus collapse were analyzed with repeated-measures ANOVAs to determine differences between preseason and postseason. Smallest detectable change (SDC) and minimal important difference (MID) values were applied to contextualize results. RESULTS: There was a significant main effect of time for non-dominant knee valgus collapse (p=0.03), but decreases in non-dominant knee valgus collapse only exceeded the SDC in the intervention team. CONCLUSIONS: Clinically meaningful decreases in knee valgus collapse may indicate a beneficial biomechanical effect of the 11+. Participation in the 11+ may lower ACL injury risk by reducing valgus collapse during a 90º cut. LEVEL OF EVIDENCE: 2b.
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OBJECTIVES: Knee injury prevention programs (IPPs) reduce knee and anterior cruciate ligament (ACL) injury rates in female athletes, however, implementation of IPPs is low. The purpose of this study was to identify barriers to implementation of IPPs among collegiate women's soccer coaches. DESIGN: Cross-sectional survey. METHODS: A custom survey based on the RE-AIM (reach, effectiveness, adoption, implementation, maintenance) framework and existing literature was sent to 151 out of 153 women's National Collegiate Athletic Association (NCAA) soccer coaches in the NCAA's Eastern Region. RESULTS: Ten respondents reported that they did not use an IPP (Non-users), and nineteen respondents reported that they did use an IPP (Users). "Cost" was the most highly ranked barrier (median rank: 2) to implementing an IPP among Non-users. For the statement, "Who should be responsible for completing an IPP," Users said "Coaches" (47%) and "Other" (21%), while Non-users said "Strength and conditioning" (50%) and "Athletic trainers" (30%). Respondents who marked "Other", elaborated that it was the responsibility of coaches, athletes, and additional staff members. CONCLUSIONS: Cost was the primary barrier to implementation of an IPP. Since the majority of Non-users indicated that implementation of an IPP was the responsibility of a non-coaching staff member, cost may be a surrogate for the expense of hiring an additional staff member rather than the cost of performing the IPP itself. Additionally, using a team-based approach that encompasses athletes, coaches, and non-coaching staff members may support long-term implementation of IPPs.
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Traumatismos em Atletas/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Traumatismos do Joelho/prevenção & controle , Tutoria , Prevenção Primária , Futebol/lesões , Estudos Transversais , Feminino , Humanos , Inquéritos e Questionários , UniversidadesRESUMO
BACKGROUND: Decelerating and cutting are two common movements during which non-contact anterior cruciate ligament (ACL) injuries occur in soccer players. Retrospective video analysis of ACL injuries has demonstrated that players are often in knee valgus at the time of injury. PURPOSE: To determine whether prospectively measured components of valgus collapse during a deceleration and 90 ° cut can differentiate between collegiate women's soccer players who go on to non-contact ACL injury. DESIGN: Secondary analysis of prospectively collected data. METHODS: 51 NCAA women's soccer players completed motion analysis of a deceleration and 90 ° before the competitive season. Players were classified as Injured (noncontact ACL injury during the season) or Uninjured at the end of the season. Differences between groups for peak hip adduction, internal rotation, and knee abduction angles, and knee valgus collapse were analyzed with a MANOVA. RESULTS: Four non-contact ACL injuries were reported at the end of the season. There was a significant difference between groups for hip adduction angle during the 90 ° cut (p = 0.02) and deceleration (p = 0.03). Players who went on to ACL injury were in more hip adduction. CONCLUSIONS: Hip adduction angle is larger in players who go on to ACL injury than those who do not during two sport-specific tasks. The components of knee injury prevention programs that address proximal control and strength are likely crucial for preventing ACL injuries. LEVEL OF EVIDENCE: 2b.
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OBJECTIVE: To determine whether the addition of perturbation training to a secondary injury prevention program reduces the rate of second anterior cruciate ligament (ACL) injury compared to the prevention program alone. DESIGN: Single-blinded randomized controlled trial. METHODS: Thirty-nine female athletes who intended to return to cutting/pivoting sports were enrolled 3 to 9 months after primary anterior cruciate ligament reconstruction (ACLR). Athletes were randomized to receive a training program of either progressive strengthening, agility, plyometrics, and prevention (SAPP) (n = 20) or SAPP plus perturbation training (n = 19); each had 10 sessions over 5 weeks. Occurrence and side of second ACL injury were recorded for 2 years after primary ACLR. RESULTS: There were 9 second ACL injuries in the 2 years after ACLR. There was no statistically significant difference in rate or side of second ACL injury between the SAPP-plus-perturbation training and SAPP groups. CONCLUSION: Adding perturbation training to a secondary ACL injury prevention program did not affect the rate of second ACL injury in female athletes. J Orthop Sports Phys Ther 2020;50(9):523-530. Epub 1 Aug 2020. doi:10.2519/jospt.2020.9407.
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Lesões do Ligamento Cruzado Anterior/prevenção & controle , Traumatismos em Atletas/prevenção & controle , Terapia por Exercício/métodos , Treinamento Resistido/métodos , Prevenção Secundária , Adolescente , Adulto , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior , Traumatismos em Atletas/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Volta ao Esporte , Método Simples-Cego , Adulto JovemRESUMO
BACKGROUND: The tuck jump assessment was developed to identify players at risk for anterior cruciate ligament (ACL) injuries or gauge a player's progress through rehabilitation after ACL reconstruction. A tuck jump score of ≥ 6 out of 10 has been labeled poor and thought to identify players with high risk landing patterns. PURPOSE: The purpose of this exploratory study was to examine if there was a relationship between tuck jump score, particularly tuck jump scores ≥ 6, hopping performance, and patient-reported outcome measures in female soccer players with ACL reconstruction (ACLR) and knee-healthy controls. STUDY DESIGN: Secondary analysis of prospective cohort study. METHODS: Female soccer players (117 after ACLR, 117 knee-healthy) performed the single hop for distance, tuck jump assessment, and drop vertical jump (DVJ). All players were categorized based on as having a total tuck jump score ≥ 6 or < 6. Analyzing all players together, Spearman's rank correlations assessed if there were relationships between total tuck jump score or tuck jump scores ≥ 6 and single-legged hop limb symmetry or DVJ measures. Players with an ACLR also filled out the International Knee Documentation Committee 2000 Subjective Knee Form and the Knee injury Osteoarthritis Outcome Score. Spearman's rank correlations assessed if there were relationships between total tuck jump score or tuck jump scores ≥ 6 and patient-reported outcome measures. RESULTS: The mean tuck jump scores was 4.8 ± 1.8 (tuck jump score ≥ 6, 6.7 ± 0.9, tuck jump score < 6, 3.7 ± 1.1) with 87 (37%) athletes having tuck jump score ≥ 6. There were no significant relationships between tuck jump score or tuck jump score ≥ 6 and hopping performance or patient-reported outcome measures. CONCLUSION: The results of this current study indicate that tuck jump scores, including tuck jump scores ≥ 6, may not be related to functional or patient-reported outcome measures. Further work is needed to examine the clinical utility of the tuck jump assessment. LEVEL OF EVIDENCE: 2.
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PURPOSE: To examine differences between men and women football players in clinically feasible jumping measures. METHODS: Female football players (N = 46, ages 16-25) were matched based on age, training frequency, and playing position with 46 male players. All players performed the tuck jump and drop vertical jump (DVJ). DVJ was assessed quantitatively for valgus knee motion and probability of a high peak knee abduction moment (pKAM), as well as sagittal plane hip, knee, and ankle angles, and qualitatively with visual assessment of the player's knees upon landing; graded as good, reduced, or poor control. RESULT: Women had higher total tuck jump scores (5 ± 2) (more technique flaws), than men (3 ± 2, P < 0.01). The quantitative analysis of the DVJ found that men had greater asymmetries between limbs, but women landed bilaterally in more knee valgus (interaction P = 0.04, main effect of sex P = 0.02). There was no difference in pKAM (interaction n.s.). Women also landed in less hip flexion (P = 0.01) and ankle dorsiflexion (P = 0.01) than men. The qualitative DVJ analysis found that more women (48%) had poor knee control compared to men (11%, P < 0.01). CONCLUSIONS: The results indicate that women perform worse on the tuck jump assessment than men. The results support previous findings that women land in more knee valgus than men, but also found that men may have larger asymmetries in knee valgus. These results from clinically feasible measures provide some suggestions for clinicians to consider during ACL reconstruction rehabilitation to enhance performance.
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Articulação do Joelho/fisiologia , Movimento/fisiologia , Futebol/fisiologia , Adolescente , Adulto , Lesões do Ligamento Cruzado Anterior/fisiopatologia , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Fatores Sexuais , Futebol/lesões , Adulto JovemRESUMO
PURPOSE: To determine if female football players who had longer durations of rehabilitation, measured in months, after anterior cruciate ligament reconstruction would have lower tuck jump scores (fewer technique flaws) and smaller asymmetries during drop vertical jump landing. METHODS: One-hundred-and-seventeen female football players, aged 16-25 years, after primary unilateral ACL reconstruction (median 16 months, range 6-39) were included. Athletes reported the duration of rehabilitation they performed after anterior cruciate ligament reconstruction. Athletes also performed the tuck jump and drop vertical jump tests. Outcome variables were: tuck jump score, frontal plane knee motion and probability of peak knee abduction moment during drop vertical jump landing. RESULTS: There was no difference in tuck jump score based on duration of rehabilitation (n.s.). No interaction (n.s.), difference between limbs (n.s.), or duration of rehabilitation (n.s.) was found for peak knee abduction moment during drop vertical jump landing. No interaction (n.s.) or difference between limbs (n.s.) was found for frontal plane knee motion, but there was a difference based on duration of rehabilitation (P = 0.01). Athletes with > 9 months of rehabilitation had more frontal plane knee motion (medial knee displacement) than athletes with < 6 months (P = 0.01) or 6-9 months (P = 0.03). CONCLUSION: As there was no difference in tuck jump score or peak knee abduction moment based on duration of rehabilitation, the results of this study press upon clinicians the importance of using objective measures to progress rehabilitation and clear athletes for return to sport, rather than time alone. LEVEL OF EVIDENCE: II.