Y-balance test performance and BMI are associated with ankle sprain injury in collegiate male athletes

Y-Balance Test performance for predicting plantar fasciitis in male recreational marathon runners: a prospective cohort study

BACKGROUND

Plantar fasciitis (PF) is the third most common type of running-related overuse injury. The purpose of this study was to investigate whether the performance of the Y-balance test (YBT) could predict PF development in male recreational marathon runners.

METHODS

One hundred and seventy-two male recreational marathon runners underwent the YBT and were then tracked for PF development during a 3-month period. Twelve participants developed PF. Their baseline data were compared to those of runners who remained uninjured.

RESULTS

During the 3-month follow-up, 7% of the marathon runners sustained PF. The posterolateral interlimb asymmetry observed during the YBT (YBT-PL) was significantly greater in injured runners than in uninjured runners (OR=1.183; 95% CI: 1.050-1.333; P=0.006) and was significantly correlated with PF development. Moreover, the area under the receiver operating characteristic (ROC) curves of the YBT-PL interlimb asymmetry was 0.779 (95% CI: 0.646-0.913; P=0.001).

CONCLUSIONS

YBT-PL interlimb asymmetry was associated with a greater likelihood of developing PF, and YBT-PL interlimb asymmetry greater than 4.5 cm was a strong risk factor for the development of PF in male recreational marathon runners. For every 1-cm increase in the interlimb asymmetry of YBT-PL, the risk of developing PF increased 1.183-fold. Practitioners should consider improving interlimb asymmetry as an injury prevention and treatment strategy.

Recurrent sprains of chronic ankle instability with chronic syndesmotic injury are primarily correlated with plantarflexion instability and multisensory deficits

OBJECTIVE

To investigate postural control deficits and their correlation with recurrent ankle sprains in patients with both chronic ankle instability (CAI) and chronic syndesmotic injury (CSI).

DESIGN

Cross-sectional design.

SETTING

Motion laboratory and Orthopedic department.

PARTICIPANTS

73 individuals with CAI and 15 healthy controls Main outcome measures: Patients with CAI were divided into a CAI group (isolated CAI) and a CSI group (CAI with CSI) based on arthroscopic findings. Postural control was evaluated using the Sensory Organization Test, Adaptability Test, and Romberg Test.

RESULTS

The CSI group had significantly lower somatosensory, visual, and vestibular scores and higher visual dependency compared to CAI group and controls (p < 0.05-0.001). CSI groups showed higher sway energy than the CAI in the plantarflexion sway (p < 0.05). Correlation analysis indicated strong associations between sprain incidence and plantarflexion sway energy (r = 0.68, p < 0.001), VAS scores (r = 0.54, p < 0.001), and somatosensory deficits (r = -0.43, p < 0.001). The AUC for the logistic regression model was 0.906, indicating excellent model performance (p < 0.001).

CONCLUSIONS

Our results found that plantarflexion instability of the CSI correlates most strongly with the risk of ankle sprains, despite coexisting multisensory deficits. Hence, rehabilitation should address these deficits, pain management and targeted training.

Association between pre-season lower limb interlimb asymmetry and non-contact lower limb injuries in elite male volleyball players

This study aimed to quantify lower limb interlimb asymmetries in elite male volleyball players by assessing key performance measures, including vertical jumps, change of direction, and muscle strength. It further explored the potential association between these asymmetries and the occurrence of non-contact lower limb injuries. Thirty-one elite male volleyball athletes (age: 20.1 ± 1.2 years; training experience: 7.1 ± 2.2 years) participated in the study. Interlimb asymmetries were assessed using the single-leg countermovement jump (SCMJ), squat jump (SSJ), drop jump (SDJ), T-test, and Pro-test to evaluate lower limb power, agility, and change-of-direction ability. Concentric and eccentric strengths of the knee extensors and flexors were measured using isokinetic testing. Athletes were monitored for 8 months to record non-contact lower limb injuries. Significant variability was observed in the lower extremity interlimb asymmetries (ranging from 3.61 to 15.91%) across different tests (P < 0.05). Thirteen athletes sustained at least one non-contact lower limb injury during the follow-up period. Logistic regression analysis identified significant predictors of injury risk: knee extensor concentric normalized peak torque asymmetry (OR 1.64 [95% CI 1.14-2.37]; P < 0.01), SCMJ height asymmetry (OR 1.18 [95% CI 1.01-1.34]; P < 0.05), and T-test performance asymmetry (OR 1.41 [95% CI 1.07-1.85]; P < 0.05). Interlimb asymmetries in SCMJ, knee extensor strength, and T-test performance are significant risk factors for non-contact lower limb injuries in elite male volleyball players. Systematic evaluation of these asymmetries could contribute to targeted injury prevention strategies and optimized athletic performance.

Modified Star Excursion Balance Testing at 12 Months After Anterior Cruciate Ligament Reconstruction: Is There a Difference Between Quadriceps or Hamstring Tendon Autografts?

Background

Quadriceps tendon (QT) autograft has emerged as an increasingly popular graft for anterior cruciate ligament reconstruction (ACLR). The modified Star Excursion Balance Test (MSEBT) measures dynamic balance and is frequently used in evaluating preparedness to return to sport as part of return-to-sport test batteries. There is limited information available about the MSEBT performance of patients who have undergone ACLR with QT autograft.

Hypothesis/Purpose

The purpose was to compare the MSEBT performance at 12 months after primary ACLR of patients with QT autografts with the performance of patients with hamstring tendon (HS) autografts. It was hypothesized that there would be a difference in the 2 groups due to harvest from either an extensor or a flexor of the knee joint.

Study Design

Cohort study; Level of evidence, 3.

Methods

The cohort consisted of 132 patients (44 patients with QT, 88 patients with HS) who had undergone primary ACLR with either a QT or HS autograft, were <30 years of age at the time of surgery, and had participated in sports regularly before injury. Patients with contralateral anterior cruciate ligament injury or an additional lateral extra-articular tenodesis were excluded. The mean age of the patients was 22.1 years, and 18% were female. The anterior reach, posterolateral reach, and posteromedial reach on the MSEBT were recorded at 12 months postoperatively and normalized to leg length. The limb symmetry index (LSI) and the composite score (CS) were calculated for each measurement. Patient-reported outcome measures were also collected.

Results

There were no significant differences between the mean LSI and the CS of the QT and HS groups for any reach direction of the MSEBT (LSI: QT = 99.9 and HS = 98.9 for anterior reach, QT = 100.9 and HS = 100.2 for posterolateral reach; QT = 101.1 and HS = 100.8 for posteromedial reach, CS: QT = 96.6 and HS = 96.9). Patient-reported outcome measures also showed no significant difference.

Conclusion

There were no differences in symmetry between QT and HS grafts in MSEBT performance at 12 months, with both patient groups having >98% limb symmetry in each reach direction.

Risk Assessment of FMS and YBT on Sports Injuries in Collegiate Athletes

This prospective cohort study investigated the predictive validity of the Functional Movement Screen (FMS) and Y Balance Test (YBT) for sports injuries in 458 collegiate athletes across various sports. Preseason screening using FMS and YBT was conducted, followed by injury data collection over the competitive season. Logistic regression analysis examined the relationship between screening scores and subsequent injury risk. Results indicated that lower composite FMS scores (≤14) were associated with increased injury risk (OR=2.32; 95% CI: 1.54-3.48; p<0.001), as were YBT anterior reach asymmetries > 4 cm (OR=2.16; 95% CI: 1.43-3.26; p<0.001). The combination of both risk factors demonstrated the strongest association (OR=3.57; 95% CI: 2.18-5.83; p<0.001) when compared to individuals with FMS scores >14 and YBT asymmetry < 4 cm.The combination of low FMS scores and YBT asymmetries demonstrated the strongest predictive value. These findings underscore the value of the FMS and YBT as screening tools to identify collegiate athletes who may be at elevated risk for sports injuries, potentially guiding the implementation of targeted injury prevention strategies.

Effects of kinesio taping on lower limb biomechanical characteristics during dynamic postural control tasks in individuals with chronic ankle instability

PURPOSE

Previous studies have demonstrated significant biomechanical differences between individuals with chronic ankle instability (CAI) and healthy controls during the Y-balance test. This study aimed to examine the effects of kinesio taping (KT) on lower limb biomechanical characteristics during the Y-balance anterior reach task in individuals with CAI.

METHODS

A total of 30 participants were recruited, comprising 15 individuals with CAI and 15 healthy controls. All participants were randomly assigned three taping conditions: no taping (NT), placebo taping (PT), and KT, followed by the Y-balance anterior reach task. Each condition was separated by one-week intervals. Kinematic and kinetic data of the lower limbs during the movement phase were collected using the Vicon motion capture system (Vicon, T40, 200 Hz) and two Kistler force platforms (Kistler, 1000 Hz).

RESULTS

KT significantly improved the Y-balance anterior reach distance (P = 0.003) and peak ankle eversion angle (P = 0.019) compared to NT. Additionally, KT resulted in increased peak knee flexion angle (P = 0.002, P = 0.011) and peak ankle dorsiflexion angle (P <0.001, P = 0.005) relative to both NT and PT. KT also significantly reduced mediolateral center of pressure (COP) displacement (P = 0.001) and average velocity of mediolateral COP displacement (P = 0.033) in comparison to NT. Furthermore, KT decreased mediolateral center of gravity displacement (P = 0.002, P = 0.003) relative to both NT and PT.

CONCLUSION

KT significantly improved abnormal ankle posture by promoting greater ankle dorsiflexion and eversion angles. Additionally, KT reduced mediolateral COP displacement and average velocity to improve postural stability. These changes may contribute to reduced risk of ankle sprains. Therefore, KT may serve as an effective tool for managing recurrent ankle sprains in individuals with CAI.

Impact of lateral ankle sprains on physical function, range of motion, isometric strength and balance in professional soccer players

Objective

Lateral ankle sprains (LASs) are prevalent in soccer and can affect long-term performance, injury recurrence and risk for chronic ankle instability. This case-control study examined functional impairments associated with LAS in professional soccer players aged 17-21.

Methods

40 players were divided into 2 groups: 21 with a history of LAS and 19 healthy matched controls. Functional assessments included the Foot and Ankle Ability Measure (FAAM), Y Balance Test (YBT), Weight Bearing Lunge Test, Heel Rise Test, Side Hop Test, and ankle and hip isometric strength measurements.

Results

Soccer players with a history of LAS exhibited significant deficits in dynamic balance, particularly in the anterior and composite YBT scores, with moderate effect sizes (p<0.05). FAAM scores also revealed functional limitations in daily activities and sports performance for the LAS group. No significant differences were observed in strength or mobility measures, including the Heel Rise, Side Hop and isometric tests. There were also no differences between injured and non-injured legs in the LAS group in the performance tests.

Conclusions

These findings highlight the persistent deficits in dynamic balance following LAS, emphasising the need for targeted rehabilitation to mitigate the risk of reinjury and enhance performance in soccer players.

Lower Extremity Asymmetry Values Derived From Multiple Strength Testing Modes Are Associated With Perceived Functional Capabilities Among University Athletes

Background: Muscle strength asymmetry and athlete introspective measures are associated with musculoskeletal (MSK) sport injury and reinjury. However, the interrelationship between mechanical and subjective measures of concentric and eccentric limb function needs further exploration. This includes investigating if an athlete's perception of their overall MSK function influences limb asymmetry across different testing modalities. Objectives: To (i) explore the interrelationship between mechanical and subjective measures of lower limb function in university athletes and (ii) compare the consistency in interlimb strength asymmetries across different strength tests in groups of athletes with good, fair, and poor perceived limb function. Methods: University athletes (n = 175; n = 87 females) from six sports completed four tests of muscle strength, power, and plyometric function along with an assessment of perceived limb function using the Sport Fitness Index (SFI). Participants were categorized into high (GOODSFI), fair (FAIRSFI), and poor (POORSFI) perceived overall MSK function (perceived function) groups. Strength asymmetry indexes evaluated interlimb differences in concentric and eccentric maximal strength, countermovement jump (CMJ) impulse, unilateral CMJ height, and reactive strength index in unilateral repeat hop testing. Cumulative link mixed-effects models assessed the relationship between strength asymmetries and perceived limb function. Results: The POORSFI group showed increased asymmetry in concentric strength testing (p = 0.022), more consistent interlimb asymmetries (p < 0.001), and reduced overall muscle strength compared to the GOODSFI group. Conclusion: Higher interlimb asymmetry in maximal concentric strength measures along with reduced muscle strength was found in the POORSFI group compared to the GOODSFI group. The POORSFI group also showed greater consistency in muscle strength asymmetry derived across different tasks.

Ankle sprains in male Israeli infantry soldiers during training: prevalence and risk factors

BACKGROUND

Given the high incidence and heavy burden of ankle sprains in recruits, large-scale, multifactorial investigations into potential risk factors are warranted. This study aimed to identify the incidence of ankle sprains and associated risk factors among new military recruits during their infantry training.

METHODS

The study included 365 infantry recruits (aged 18-21 years), who were inducted into service in March 2022. These recruits were monitored for ankle sprains throughout their basicy and advanced infantry training by a physiotherapist. Preinduction smoking habits, physical fitness preparation and recurrent ankle sprains were recorded. Anthropometric measures, lower-extremity functional movement, Achilles tendon structure, perceived ankle instability, and mechanical ankle instability were assessed at the onset of both training periods.

RESULTS

Ankle sprains were diagnosed in 109 trainees (29.9%) during both the basic and the advanced training periods. Preinduction recurrent ankle sprains were reported by 28.2% of the participants. The relative risk of a recruit with preinduction ankle sprains suffering a subsequent sprain during training was 1.66 (p=0.001). Logistic regression analysis indicated that reduced proprioception ability (OR=0.002), higher body mass index (OR=1.08), preinduction recurrent sprains (OR=1.95) and lack of physical fitness preparation (OR=3.12) were related to ankle sprains throughout the complete basic-and-advanced training period. Preinduction recurrent ankle sprains (OR=3.37) and reduced Achilles tendon quality (OR=1.30) were associated with ankle sprains during the advanced training period.

CONCLUSIONS

Lower-extremity functional movement, body mass index, preinduction recurrent sprains, physical preparation and reduced Achilles tendon quality were associated with the risk of ankle sprains during training. These findings could contribute to developing prevention and intervention programmes for reducing ankle sprains in military trainees.

Comparing reach distance between the Y-Balance Test-Lower Quarter and Star Excursion Balance Test: Are practitioners using the correct protocol?

OBJECTIVES

To compare reach distances between the YBT-LQ and SEBT using the correct protocols as outlined by the developers. This will provide an accurate insight on the actual magnitude differences in reach distance between the movement screen tests and will safeguard practitioners on the subsequent use of these outcomes to inform clinical decision making.

DESIGN

Observational.

SETTING

Laboratory.

PARTICIPANTS

Participants included sixteen healthy female subjects from the university and amateur sports teams.

MAIN OUTCOME

Reach distances in the anterior direction (ANT), posterior medial (PM) and posterior lateral (PL) between participants on the YBT-LQ and SEBT.

RESULTS

The principal findings highlighted that a statistically significantly greater reach distance on the left and right side for the YBT-LQ compared to the SEBT in the ANT, PM, and PL directions (p < 0.0005).

CONCLUSION

The results of this study suggest that the YBT-LQ and SEBT are not comparable tests due to the differences in reach distance and methodological differences. Therefore, previous, and future research using the YBT-LQ and SEBT cannot be used interchangeably. Not following developed guidelines questions the applicability of the findings of reach distance scores to infer on performance and assessment of injury risk.

The Effects of Motor Imagery on Static and Dynamic Balance and on the Fear of Re-Injury in Professional Football Players with Grade II Ankle Sprains

Lateral ankle sprains are one of the most frequent athletic injuries in football, causing deficits in balance. Motor Imagery (MI) has been successively included in sports rehabilitation as a complementary therapeutic intervention. The aim of the present study was to explore the effects of MI on static and dynamic balance and on the fear of re-injury in professional football players with Grade II ankle sprains. Fifty-eight participants were randomly allocated into two groups: First-MI group (n = 29) and second-Placebo group (n = 29), and they each received six intervention sessions. The first MI group received MI guidance in addition to the balance training program, while the second Placebo group received only relaxation guidance. One-way ANOVA showed statistically significant results for all variables, both before and 4 weeks after the interventions for both groups. The t-test showed statistically significant differences between the two groups for static balance for the right lower extremity (t = 3.25, S (two-tailed) = 0.002, p < 0.05) and also for heart rate (final value) in all time phases. Further research is needed in order to establish MI interventions in sports trauma recovery using stronger MI treatments in combination with psychophysiological factors associated with sports rehabilitation.

What is the influence of biomechanical variables on the Y balance test performance in recreational runners?

BACKGROUND

Asymmetries and poor Y balance test (YBT) performance are associated with an increased risk of injuries in athletes. The aim of this study was to investigate the association between YBT performance with biomechanical variables in runners.

METHODS

The runners underwent the YBT, followed by the assessment of center of pressure, plank position, muscle strength (MS) of hip flexors, extensors, abductors, and external rotators, knee extensors, ankle dorsiflexion range of motion (ROM), Q angle, forefoot alignment, and passive hip internal rotation. Associations between variables were examined using multiple linear regression models with the Bayesian Information Criterion.

RESULTS

122 cases were analyzed. The R2 values were 0.38; 0.05; 0.06; and 0.15 for the anterior, posteromedial, posterolateral and composite directions models, respectively. The anterior reach in the YBT was associated with ankle dorsiflexion ROM [Sβ 95%IC: 0.43 (0.32-0.55)], passive hip internal rotation [Sβ 95%IC: 0.35 (0.24-0.47)], MS of the hip extensors [Sβ 95%IC: 0.19 (0.07-0.31)] and forefoot alignment [Sβ 95%IC: 0.14 (-0.25-0.02)]. The posteromedial and posterolateral reach were associated with MS of the hip flexors [Sβ 95%IC: 0.23 (0.09-0.37) and 0.24 (0.11-0.38)], respectively. The composite score was associated with MS of the hip flexors [Sβ 95%IC: 0.31 (0.18-0.45)], ankle dorsiflexion ROM [Sβ 95%IC: 0.24 (0.10-0.37)] and Q angle [Sβ 95%IC: 0.18 (0.04-0.31)].

CONCLUSION

YBT performance in different directions demonstrated specific associations with key biomechanical factors.

Effects of plyometric training on skill-related physical fitness in badminton players: A systematic review and meta-analysis

Skill-related physical fitness significantly correlates with sports performance. Plyometric training (PT) is an effective method for improving physical fitness in athletes. However, its impact on skill-related physical fitness in badminton players remains uncertain. Therefore, this systematic review and meta-analysis aimed to evaluate the effectiveness of PT on skill-related physical fitness in badminton players. Five electronic databases (Web of Science, PubMed, SCOPUS, MEDLINE, and SPORTSDiscus) were searched until February 2024. A PICOS approach was used to identify inclusion criteria, (1) healthy badminton players, (2) a PT program, (3) an active control group, (4) a measure of skill-related physical fitness before and after PT, and (5) randomized controlled studies. The PEDro scale was used to assess the methodological quality of PT studies, while the level of evidence certainty was determined through the GRADE framework. The calculation of effect sizes (ESs) was based on mean values and standard deviations, and heterogeneity was measured with the I2 statistic. The extended Egger's test was employed to check for publication bias. Eleven studies comprising 445 badminton players were eligible for inclusion. The analysis revealed significant small-to-moderate effects of PT on power (ES = 0.60, p < 0.001), agility (ES = 0.96, p < 0.001), speed (ES = 0.63, p = 0.001), and balance (ES = 0.89; p = 0.013). However, no significant effect was observed for reaction time (ES = 0.56; p = 0.189). The certainty of evidence for outcomes was graded as either low or very low. In conclusion, our findings demonstrate that PT improved power, agility, speed, and balance, but not reaction time in badminton players. However, the small number of studies and the very low to low certainty evidence mean that these results need to be interpreted with caution.

Investigation of inter-rater and test-retest reliability of Y balance test in college students with flexible flatfoot

BACKGROUND

The Lower Quarter Y Balance Test (YBT-LQ) has been widely used to assess dynamic balance in various populations. Dynamic balance in flexible flatfoot populations is one of the risk factors for lower extremity injuries, especially in college populations in which more exercise is advocated. However, no study has demonstrated the reliability of the YBT-LQ in a college student flexible flatfoot population.

METHODS

A cross-sectional observational study. 30 college students with flexible flatfoot were recruited from Beijing Sports University. They have been thrice assessed for the maximal reach distance of YBT under the support of the lower limb on the flatfoot side. Test and retest were performed with an interval of 14 days. The outcome measures using the composite score and normalized maximal reach distances in three directions (anterior, posteromedial, and posterolateral). The relative reliability was reported as the Intraclass Correlation Coefficient (ICC). Minimal Detectable Change (MDC), Smallest worthwhile change (SWC), and Standard Error of Measurement (SEM) were used to report the absolute reliability.

RESULTS

For inter-rater reliability, the ICC values for all directions ranged from 0.84 to 0.92, SEM values ranged from 2.01 to 3.10%, SWC values ranged from 3.67 to 5.12%, and MDC95% values ranged from 5.58 to 8.60%. For test-retest reliability, the ICC values for all directions ranged from 0.81 to 0.92, SEM values ranged from 1.80 to 2.97%, SWC values ranged from 3.75 to 5.61%, and MDC95% values ranged from 4.98 to 8.24%.

CONCLUSIONS

The YBT-LQ has "good" to "excellent" inter-rater and test-retest reliability. It appears to be a reliable assessment to use with college students with flexible flatfoot.

TRIAL REGISTRATION

This trial was prospectively registered at the Chinese Clinical Trial Registry with the ID number ChiCTR2300075906 on 19/09/2023.

Factors Associated With a Lateral Ankle Sprain in Young Female Soccer Players: A Prospective Cohort Study

Background

Previous studies have attempted to determine if certain risk factors can predict the occurrence of a lateral ankle sprain (LAS) in female soccer players. Unfortunately, there is limited evidence with regard to risk factors associated with an LAS in female soccer players.

Purpose

To identify intrinsic risk factors for an LAS among young female soccer players.

Study Design

Cohort study; Level of evidence, 2.

Methods

Participants were 161 young female soccer players in Japan who were evaluated for LAS risk factors during a preseason medical assessment. The assessment included anthropometric, joint laxity, joint range of motion, muscle flexibility, muscle strength, and balance measurements. Each athlete's history of LASs was also collected. The participants were monitored during a single-yearseason for LASs, as diagnosed by physicians.

Results

There were 26 instances of an LAS in 25 players (15.5%) during the season. Injured players were significantly more likely to have sustained a previous ankle sprain (P = .045) and demonstrated significantly worse balance than their peers without an LAS during the double- and single-leg balance tests (P = .008 for both). Athletes with lower hamstring-to-quadriceps muscle strength ratios were also significantly more likely to sustain an LAS (P = .02).

Conclusion

Poor balance, a low hamstring-to-quadriceps ratio, and a history of ankle sprains were associated with an increased risk of LASs in young female soccer players in the current study. These findings may be useful for developing a program to prevent LASs in this population.

Evaluation of the Value of the Y-Balance Test to Predict Lower Limb Injuries in Professional Male Footballers

CONTEXT

The aim of this prospective cohort study was to identify whether Y-Balance Test (YBT) performance and asymmetry are associated with lower limb injury in elite adult football athletes.

DESIGN

A prospective cohort study.

METHODS

Preseason YBT measures were obtained from 121 male footballers participating in National League One across the 2021-2022 season. Lower limb injuries were tracked across the season to determine the relationship between YBT variables and injury incidence using logistic regression analysis. The statistical significance level was .05.

RESULTS

The average YBT score was 111.0 (5.8) cm on the left limb and 112.0 (5.5) cm on the right limb, with an average asymmetry of 2.3 (1.4) cm. Athletes with lower YBT scores on both the left (odds ratio = 2.9; 95% confidence interval, 1.7 to 4.8: P ≤ .001) and right (odds ratio = 2.3; 95% confidence interval, 1.6 to 3.2: P ≤ .001) limbs were at a greater risk of injury. Similarly, athletes with greater amounts of asymmetry were also more likely to get injured (odds ratio = 2.1; 95% confidence interval, 1.3 to 3.3: P = .002).

CONCLUSIONS

Results indicate that lower and asymmetrical YBT scores have a significant relationship with future lower limb injuries in professional male footballers. The YBT offers a simple, reliable, and effective screening tool that can be used by practitioners in football to help identify players at a greater risk of injury before the season commences.

Correlation between hip muscle strength and the lower quarter Y-balance test in athletes following anterior cruciate ligament reconstruction

INTRODUCTION

The lower quarter Y-balance test (YBT-LQ), which measures dynamic postural control, has been reported to be predictive of lower limb injuries in athletes. It requires subjects to control their body while maintaining a single-leg stance, which necessitates sufficient strength of the hip muscles to maintain stability. The purpose of the study was to investigate the correlation between the performance of the YBT-LQ and the hip abductor or extensor muscle strength in athletes following anterior cruciate ligament reconstruction surgery (ACLR).

METHODS

Fifteen athletes with post-ACLR participated in this cross-sectional study. The participants completed the YBT-LQ, followed by isokinetic measurement of the hip abductor and extensor muscles of both the legs. The peak and average torque of the hip abductor and extensor muscles were tallied with the composite score of the YBT-LQ for each limb.

RESULTS

No correlation was found between the strength of the hip muscles and the YBT-LQ composite score in both injured and non-injured limbs at all velocities except for the eccentric hip abductor and concentric hip extensor torques. The eccentric hip abductor average torque is strongly associated with the YBT-LQ (r = 0.663, p = 0.010) at a speed of 180°/s. The concentric hip extensor peak torque was weakly correlated with balance (r = 0.540, p = 0.046) at a speed of 180°/s.

CONCLUSION

Our study demonstrated a positive correlation between the YBT-LQ and eccentric hip abduction and concentric hip extension at higher velocities. This shows the importance of implementing velocity-oriented rehabilitation in an athletic population following ACLR.

Sports Nutrition Knowledge Questionnaires Developed for the Athletic Population: a Systematic Review

PURPOSE OF REVIEW

Sports nutrition (SN) is pivotal in aiding athletes to reach peak performance, minimize sport-related injuries, enhance career longevity, and improve general health. An accurate assessment of athletes' sports nutrition knowledge (SNK) is required to design targeted nutrition education programs aimed at enhancing both nutritional knowledge and dietary practices. This review systematically evaluates studies that use questionnaires to assess the SNK of athletes engaged in athletics.

RECENT FINDINGS

The literature search was conducted in PubMed®, Web of Science®, and Scopus®, and 375 potentially relevant articles were identified. The total number of articles included in the present review is 11, with eight studies involving only athletic disciplines and three involving athletics and other sports. The majority (n = 8) of the questionnaires included general and SN aspects, with SN covering endurance athletes' knowledge of competition carbohydrate guidelines, gastrointestinal symptoms associated with exercise, and ultra-endurance athletes' sodium beliefs and practices. Questionnaires were either delivered online (n = 7) or self-administered in hard copy (n = 1). The three major strategies identified for developing questionnaires were based on previous literature and recent SN guidelines (n = 6), consultation with a panel of experts (n = 7), and the use of a previously developed sports nutrition knowledge questionnaires (SNKQ) (n = 4), with more than one approach used in five studies. Similarly, up to three validation approaches were used, including content, face, and construct validity. Seven studies used a test-retest procedure to ensure external reliability, and eight used Cronbach's alpha or kappa coefficient to assess internal consistency. Endurance and ultra-endurance athletes are the populations of interest for the majority of questionnaires developed for athletics, with most questionnaires incorporating general and SNK topics.

Investigation and analysis of training injury and its psychological effects on firefighters in Beijing A cross-sectional study

Firefighters' high-intensity training often leads to injuries in the musculoskeletal system. Studies have found that these injuries in the musculoskeletal system may contribute to poor psychological issues. At the same time, low psychological well-being increases the risk of injuries, illness, and mortality. According to research reports, firefighters generally have a good psychological state. So this study aims to survey and analyze the training-related injuries and psychological states of firefighting and rescue personnel in Beijing. This cross-sectional study employed a questionnaire survey to gather data from a total of 214 firefighters in a certain city. The participants were required to complete a questionnaire about musculoskeletal injuries and psychological status, and then these data were statistically analyzed. The incidence of training-related injuries is relatively high among firefighting and rescue teams, with the highest proportions observed in the lower back, knees, and ankles. Overweight and obese firefighters are more prone to ankle injuries. In the group with injuries, the subjective well-being index is lower compared to the group without injuries. Firefighters experiencing moderate to severe pain due to injuries exhibit lower subjective well-being indices compared to those with mild pain. Psychological resilience and the impact of pain on training and sleep can predict the subjective well-being index of firefighters. It is recommended that firefighting and rescue teams enhance preventive measures for musculoskeletal injuries during training to elevate the subjective well-being of firefighters.

Causal effect of body mass index and physical activity on the risk of joint sports injuries: Mendelian randomization analysis in the European population

BACKGROUND

Observational studies can suggest potential associations between variables but cannot establish a causal effect on their own. This study explored the causal associations between body mass index (BMI), physical activity (PA), and joint sports injuries.

METHODS

We conducted two-sample Mendelian randomization (MR) using publicly accessed genome-wide association studies (GWAS) datasets to investigate the causal effects of BMI and PA on joint sports injury risk. The inverse-variance weighted method was believed to be the primary MR analysis. Subsequently, sensitivity, pleiotropy, and heterogeneity analyses were employed to estimate the reliability of the results of the current research.

RESULTS

Genetically predicted increased BMI was causally related to the higher sports injury risk of the ankle-foot (OR 1.23, 95% CI 1.09-1.37, p = 4.20E-04), knee (OR 1.32, 95% CI 1.21-1.43, p = 1.57E-11), and shoulder (OR 1.23, 95% CI 1.08-1.40, p = 1.28E-03). Further, the mentioned effects were validated using another set of GWAS data on BMI. Similar causal linkages were exhibited between increased BMI and the growing risk of sports injuries of the ankle-foot (OR 1.34, 95% CI 1.13-1.60, p = 9.51E-04), knee (OR 1.26, 95% CI 1.09-1.45, p = 1.63E-03), and shoulder (OR 1.35, 95% CI 1.09-1.67, p = 5.66E-03). Additionally, accelerometer-based PA measurement (overall average acceleration) (AccAve) was negatively related to sports injuries of the ankle-foot (OR 0.93, 95% CI 0.87-0.99, p = 0.046) and lumbar spine (OR 0.68, 95% CI 0.51-0.92, p = 0.012). Furthermore, we verified that the effect of AccAve on the risk of injury at the ankle-foot still had statistical significance after adjusting BMI. Results were verified as reliable under all sensitive analyses.

CONCLUSIONS

This research determined that a higher BMI could raise the sports injury risk of the ankle-foot, knee, and shoulder, while an overall average acceleration PA could reduce the injury risk of the ankle-foot and lumbar spine. These conclusions contribute to a greater knowledge of the roles of BMI and PA in the mechanism of joint sports injuries and offer several suggestions for patients and clinicians.

Role of ankle dorsiflexion in sports performance and injury risk: A narrative review

The objective of this literature review is to understand the role of ankle dorsiflexion range of motion in sports performance and the risk of injuries. The ankle harmonizes the interaction between the body and the supporting surface through adjusting to the supporting surface and handling forces to contribute effectually to different functional activities. Ankle dorsiflexion is an essential construct in many sport-specific skills. Ankle dorsiflexion is associated with activation of brain areas involved in movement preparation, sensory integration, motor planning/execution, balance, and visuomotor coordination. Ankle dorsiflexion was associated with enhanced activation of deep core and quadriceps muscles. Decreased ankle dorsiflexion is linked to compensations and altered kinetics and kinematics that can potentially affect sports performance and increase the chances of sustaining injuries. It is vindicated to consider more focus on ankle dorsiflexion range of motion in research studies, sports-related pre-season screening, clinical examination, injury rehabilitation, and return-to-sports judgment.

Female Collegiate Dancers' Physical Fitness across Their Four-Year Programs: A Prospective Analysis

Dance is physically demanding, requiring physical fitness (PF) that includes upper body, lower body, core fitness, and balance for successful performance. Whether PF changes as dancers advance from when they enter (freshmen) to when they graduate from their collegiate program (seniors) is unclear. We prospectively compared collegiate dancers' freshman-to-senior PF. We recorded PF in regard to upper body strength endurance (push-ups), core strength endurance (front, left-side, right-side, and extensor plank hold times), lower body power (single leg hop-SLH-distances % height; Leg Symmetry Index: LSI = higher/lower × 100, %), and balance (anterior reach balance, % leg length, LL; LSI balance = higher/lower × 100, %) in 23 female collegiate dancers (freshman age = 18.2 ± 0.6 years). Repeated measures ANOVAs (p ≤ 0.05) were used to compare measures from freshman to senior years. Across their collegiate programs, dancers' PF remained unchanged. Specifically, their upper body strength endurance push-up numbers (p = 0.93), their core strength endurance plank times (left: p = 0.44, right: p = 0.67, front: p = 0.60, p = 0.22), their SLH distances (left: p = 0.44, right: p = 0.85), and their symmetry (p = 0.16) stayed similar. Also, dancers' right leg (p = 0.08) and left leg balance (p = 0.06) remained similar, with better balance symmetry (p < 0.001) in seniors. Overall, dancers' PF did not change across their collegiate programs. Thus, female dancers' freshman PF may be an adequate baseline reference measure when devising rehabilitation programs and determining readiness-to-return-to-activity post injury.

Who Does Not Respond to Injury Prevention Warm-up Programs? A Secondary Analysis of Trial Data From Neuromuscular Training Programs in Youth Basketball, Soccer, and Physical Education

OBJECTIVES: To identify factors associated with nonresponse to neuromuscular training (NMT) warm-up programs among youth exposed to NMT warm-ups. METHODS: This is a secondary analysis of youth (aged 11-18 years) in the intervention groups of 4 randomized controlled trials in high school basketball, youth community soccer, and junior high school physical education. Youth who were exposed to NMT and who sustained an injury during the study were considered nonresponders. Odds ratios (ORs) were based on generalized estimating equations logistic regression controlling for clustering by team/class and adjusted for age, weight, height, balance performance, injury history, sex, and sport (soccer/basketball/physical education). RESULTS: A total of 1793 youth were included. Youth with a history of injury in the previous year had higher odds (OR = 1.64; 95% CI: 1.14, 2.37) of injury during the study, and females were more likely (OR = 1.67; 95% CI: 1.21, 2.31) to sustain an injury than males who were participating in NMT. Age was not associated with the odds of sustaining an injury (OR = 1.10; 95% CI: 0.93, 1.30). Soccer players benefited most from greater adherence, with 81% lower odds of injury (OR = 0.19; 95% CI: 0.06, 0.57) when completing 3 NMT sessions a week compared with 1 session per week. CONCLUSION: Factors associated with nonresponse to an NMT warm-up program were female sex, history of injury during the previous 12 months, and lower weekly NMT session adherence in some sports (soccer). J Orthop Sports Phys Ther 2023;53(2):94-102. Epub: 9 December 2022. doi:10.2519/jospt.2022.11526.

Intrinsic Risk Factors for Ankle Sprain Differ Between Male and Female Athletes: A Systematic Review and Meta-Analysis

Background

Ankle sprains remain prevalent across most team sports. However, despite divergent ankle sprain injury rates in male and female athletes, little is known about potential sex-specific risk factors for ankle sprain.

Objective

To systematically investigate the sex-specific risk factors for ankle sprain.

Methods

Combinations of the key terms were entered into PubMed, Web of Science, Embase and Cochrane Library databases, and prospective studies reporting ankle sprain risk factors in males or females were included for meta-analysis.

Results

Sixteen studies were eligible for inclusion, for a total of 3636 athletes (735 female) and 576 ankle sprains (117 female). Out of 21 prognostic factors, previous ankle sprain injury (odds ratio = 2.74, P < .001), higher body mass index (SMD = 0.50, P < 0.001), higher weight (SMD = 0.24, P = 0.02), lower isometric hip abduction strength (SMD = − 0.52, P < 0.0001) and lower dynamic balance performance (SMD = − 0.48 to − 0.22, P < 0.001–0.04) were identified as risk factors in male athletes. In female athletes, out of 18 factors eligible for meta-analysis, only lower concentric dorsiflexion strength was identified as a risk factor (SMD = − 0.48, P = 0.005).

Conclusion

This meta-analysis provides novel evidence for different risk factor profiles for ankle sprain injuries between female and male athletes. Further studies, particularly in female athletes, are needed to strengthen the evidence.

Effect of balance training on footwork performance in badminton: An interventional study

Badminton is a racket sport that requires a wide variety of proficient postural changes and moves including jumps, lunges, quick changes in direction, and rapid arm movements. Efficient movement in badminton court entails reaching the shuttlecock in as few steps as possible while maintaining good balance. Balance training is an unexplored component in badminton training protocol, though balance is important in injury prevention and performance enhancement. We aimed to investigate the effectiveness of balance training on sport-specific footwork performance of school-level competitive badminton players. We conducted a controlled trial involving 20 male badminton players (age 12.85±0.67 years). Participants were stratified according to their level of performance in the game, and payers from each stratum were randomly assigned to control and intervention groups. The control group (n = 8) engaged in 2 hours of ordinary badminton training, whereas the intervention group (n = 12) underwent 30 minutes of balance training followed by 1 hour and 30 minutes of ordinary badminton training, 2 days per week for 8 weeks. We tested the participants at baseline and after 8 weeks for static balance (Unipedal Stance Test), dynamic balance (Star Excursion Balance Test) and sport-specific footwork performance (shuttle run time and push-off times during stroke-play). On pre- vs. post-intervention comparisons, both groups improved in static balance (eyes opened) (p<0.05), but only the intervention group improved in dynamic balance (p = 0.036) and shuttle-run time (p = 0.020). The intervention group also improved push-off times for front forehand (p = 0.045), side forehand (p = 0.029) and rear around-the-head shots (p = 0.041). These improvements in push-off times varied between 19-36% of the baseline. None of the footwork performance measures significantly improved in the control group. Our findings indicate that incorporating a 30-minute balance training program into a regular training schedule improves dynamic balance, and on-court sport-specific footwork performance in adolescent competitive badminton players, after 8 weeks of training.

Kinetic Effects of 6 Weeks' Pilates or Balance Training in College Soccer Players with Chronic Ankle Instability

Lateral ankle sprain (LAS) is a common sports injury that frequently occurs in active individuals. LAS is characterized by a high recurrence rate, with a large proportion of patients progressing to chronic ankle instability (CAI). Pilates exercises have provided positive results in health care and in rehabilitation. This study compared Pilates training (PT) with traditional balance training (BT) in patients with CAI. Fifty-one college football players with CAI, divided into PT (n = 26) and BT (n = 25) groups, were included in the study. The groups performed PT or BT training as assigned, three times per week for 6 weeks. Isokinetic ankle strength, one-leg hop tests, Y-balance test (YBT), and foot and ankle outcome score (FAOS) were evaluated before and after training. There were considerable improvements in both the PT and BT groups after training. Group and time comparisons revealed that the PT group achieved better triple hop test results than the BT group, whereas the BT group exhibited a greater improvement in YBT posteromedial and posterolateral reach distances. In athletes with CAI, both PT and BT effectively improved symptoms and function. These findings suggest that ankle strength, balance, and core stability should be comprehensively evaluated and targeted in CAI rehabilitation programs.

Effect of Ankle Proprioception Training on Preventing Ankle Injury of Martial Arts Athletes

Martial arts routines originated in China and are a traditional sport of the Chinese nation. They are one of the outstanding sports culture representatives in China since ancient times. Excessively difficult movements in some martial arts routines during competitions or training can cause athlete injuries. The purpose of this article is to study the effect of proprioceptive training of ankle joints on preventing ankle injuries in martial arts athletes. Can ankle strength training and ankle proprioceptive training combined with strength training improve the dynamic and static balance of football players? This article analyzes the mechanism and causes of martial arts athletes' injuries and proposes treatment methods for ankle injuries. In the experimental part of this article, 16 martial arts athletes (8 males and 8 females) were selected as research objects, and they were randomly divided into 4 male and female experimental groups and 4 control groups. The experimental group received ankle muscle strength training for 6 weeks, and the control group received ankle muscle strength training and ankle proprioception training. The experimental results prove that ankle proprioceptive training can improve the dynamic and static balance of martial arts athletes and can effectively prevent the occurrence of ankle injury. In this paper, the dynamic balance ability in the biped standing state with eyes closed was tested, and the reductions of the stability index in the front and back directions of the control group and the experimental group were 0.03 and 0.2, respectively. It can be seen that the stability training effect of the experimental group was obvious.

Association between Selected Screening Tests and Knee Alignment in Single-Leg Tasks among Young Football Players

This study aimed to examine the relationship between knee valgus in the frontal plane projection angle (FPPA) during single-leg squat (SLS), single-leg landing (SLL), and other selected clinical tests in young athletes. Forty-three young healthy elite football players (age: 13.2 (1.7) years) that were regularly training in a local sports club participated in the study. The FPPA was assessed using 2D video analysis. The screening tests included the passive single-leg raise (PSLR), hip external and internal rotation (hip ER and IR), sit and reach test, weight-bearing lunge test (WBLT), modified star excursion balance test (mSEBT), countermovement jump (CMJ), single-leg hop for distance (SLHD), and age peak height velocity (APHV). There was a significant positive relationship between the knee valgus angles in the SLS test and the sit and reach test (r = 0.34) and a negative relationship with the hip ER ROM (r = −0.34) (p < 0.05). The knee valgus angles in the SLL were negatively associated with the hip IR (r = −0.32) and ER ROM (r = −0.34) and positive associated with the WBLT (r = 0.35) and sit and reach test (r = 0.33) (p < 0.05). Linear regression analysis showed that the results of the hip ER ROM and sit and reach tests were independent predictors of the FPPA in the SLS test (r2 = 0.11, p = 0.03 and r2 = 0.12, p = 0.02, respectively). The conducted study showed that individuals with more hip range of motion, more spine flexion extensibility, and less ankle dorsiflexion ROM may be more likely to experience high degrees of knee valgus in FPPA.

Risk factors for injuries in female soldiers: a systematic review

Background

Female soldiers form an integral part of any modern defence force. Previous reports have highlighted that female soldiers report injuries at higher rates than male personnel. One possible reason for this is an actual difference in underlying injury rates, purported to be due to several factors, including levels of fitness. The aim of this review was to determine risk factors for injuries in female soldiers.

Methods

A systematic search was conducted for studies which reported on risk factors for injuries in female soldiers. Databases searched included PUBMED, CINAHL and Medline through OVID. Eligible studies were rated for their methodological quality using the Critical Appraisal Skills Program (CASP) tools and data were extracted and synthesized using a critical narrative approach.

Results

A total of 18 articles were included in this review which reported on 18 risk factors for injury. Smoking, previous injury, no history of deployment, heavy occupational tasks, lower levels of aerobic fitness and lower number of push-up repetitions appear to be risk factors for injuries in female soldiers. Age, height, body fat, high or low BMI and body mass do not appear to be consistent risk factors for injury in female soldiers and there appears to be minimal evidence for current levels of activity, sit-up ability, and other assessments of strength, power, speed, or movement being associated with injury risk. Additionally, neither flexibility nor previous levels of activity appear to be associated with injury risk in female soldiers.

Conclusion

Strategies to improve aerobic fitness and upper limb endurance, reduce smoking, and optimise rehabilitation from injuries and risk management for heavy occupational tasks need to be developed for female soldiers. Such strategies are also likely to reduce risks for male soldiers.

Limb Dominance Does Not Affect Y-Balance Test Performance in Non-Athlete Adolescents

BACKGROUND

The Lower Quarter Y-Balance Test (YBT-LQ) has been shown to be reliable for assessing dynamic balance in children and adolescents. However, limited research is available about the effects of leg dominance on YBT-LQ performance in adolescents. In addition, there is no consensus on the use of maximum reach or mean reach distance being a better measure of YBT-LQ performance.

HYPOTHESIS/PURPOSE

The purposes of this study were to determine if there is a difference in the YBT-LQ performance between the dominant and non-dominant limbs in non-athlete adolescents, and to compare the reliability of the maximum reach scores to that of the mean reach scores in this population.

STUDY DESIGN

Prospective cohort study.

METHODS

Twenty-six healthy non-athlete adolescents (13.6 ± 1.0 years, 22 girls, 4 boys) performed the YBT-LQ on two separate days while the same investigator scored their performance. Paired t-tests were used to compare reach distances on dominant and non-dominate stance limbs. Intraclass correlation coefficients (ICC3,1) were calculated for the maximum and mean reach distances for three directions (anterior, posterolateral, posteromedial) and the composite scores on each limb.

RESULTS

There was no significant difference in YBT-LQ performance between dominant and non-dominant stance limbs (p > 0.05). Overall, the between-day intra-rater reliability for maximum reach and mean reach scores was moderate-to-good for both limbs (ICC3,1 = 0.59 - 0.83), but was poor for the composite score on the dominant limb (ICC3,1 = 0.42) and maximum anterior reach on non-dominant limb (ICC3,1 = 0.48).

CONCLUSION

Limb dominance does not seem to be a factor for YBT-LQ performance in this population. The YBT-LQ appears to be a reliable tool for dynamic balance assessment in non-athlete adolescents using the individual score of each direction. The use of mean reach measures seems to slightly improve reliability, specifically the anterior reach direction, in this population.

LEVEL OF EVIDENCE

Level 2b.

The Effect of a Handball Warm-Up Program on Dynamic Balance among Elite Adolescent Handball Players

This study examined the effect of the handball warm-up program (HWP) on dynamic balance among elite adolescent handball players. In this case, 24 handball players were randomly assigned into experimental warm-up and control groups. The HWP was performed over 8 weeks (3 times per week). Dynamic balance before and after the intervention training programs were measured by the Biodex Balance System (BBS) and Y Balance test for the dominant (DL) and non-dominant legs (non-DL). After HWP training, BBS scores significantly improved in the overall (OSI) (30.4% and 31.1%), anterior-posterior (APSI) (44.6% and 35.2%), and medial-lateral stability indexes (MLSI) (38.8% and 43%) for both DL and non-DL. Post-training, the Y Balance test exhibited significant improvements in OSI (13.2% and 10.6%), anterior (17.2% and 12.6%), posteriolateral (12.8% and 11.3%), and posteriomedial stability indexes (9.2% and 7.9%) with DL and non-DL, respectively. In conclusion, dynamic balance improved overall after eight weeks of the HWP, with this improvement significantly greater with the trained versus the control group. Optimal balance during handball is an important factor to ensure coordinated and efficient movements and it is speculated that improved balance could positively impact injury prevention. Hence, the HWP program can be used as an alternative to a conventional warm-up program.

Association between Inter-Limb Asymmetries in Lower-Limb Functional Performance and Sport Injury: A Systematic Review of Prospective Cohort Studies

Background: Inter-limb asymmetry in lower-limb functional performance has been associated with increased risk of sport injury; however, findings are not always consistent. Purpose: To conduct a systematic review on whether inter-limb asymmetry in lower-limb functional performance can predict sport injury. Methods: Four electronic databases (MEDLINE, EMBASE, Web of Science, and SportDiscus) were systematically searched for prospective cohort studies reporting the association between inter-limb asymmetry in lower-limb functional performance and sport injury. Results: A total of 28 prospective cohort studies were included in the analyses. Collectively, the findings were highly inconsistent, and a clear statement on the association between each asymmetry and sport injury was difficult. Conclusions: Highly inconsistent findings make it difficult to create clear recommendations on the relationship between the inter-limb asymmetry in lower-limb functional performance (power, muscle flexibility, and dynamic balance) and sport injury. The influence of potential factors (selection of tests/parameters, participant characteristics, definition of injury, and ways of calculating asymmetry) should be considered when using previous findings.

Can a Modified Y-Balance Test Predict Running Overuse Injuries over the Course of a Division I Collegiate Cross-Country Season?

BACKGROUND

Collegiate distance runners often suffer from running overuse injuries (ROI). The Y-Balance Test (YBT) has the potential to predict ROI risk in collegiate runners.

PURPOSE

To investigate whether a preseason clinical assessment of dynamic balance, through a modified version of the YBT (mYBT), can predict risk of ROIs during one NCAA Division I cross-country (XC) season.

STUDY DESIGN

Prospective case-control study.

METHODS

Participants from a Division I XC team were screened for mYBT performance in four directions: anterior (AN), posteromedial (PM), posterolateral (PL), and posterior (PO). ROIs were tracked over the course of the XC season. Receiver operating characteristic (ROC) curve analysis (α = 0.05) was utilized to investigate the effectiveness of the mYBT in predicting injury risk.

RESULTS

Nine (5 female, 4 male) of 29 runners developed an ROI during the XC season. Five components of the mYBT were found to predict injuries, including normalized nondominant PO score (AUC = 0.756, p = 0.03; RR = 1.90), AN raw difference and limb asymmetry (AUC = 0.808, p = 0.01), and PM raw difference and limb asymmetry in males (AUC = 0.958, p = 0.02).

CONCLUSION

Specific components of the mYBT can help predict the risk of developing a running overuse injury over one Division I XC season.

LEVEL OF EVIDENCE

Screening, Level 3.

Systematic Review and Meta-Analysis of the Y-Balance Test Lower Quarter: Reliability, Discriminant Validity, and Predictive Validity

BACKGROUND

Deficits in dynamic neuromuscular control have been associated with post-injury sequelae and increased injury risk. The Y-Balance Test Lower Quarter (YBT-LQ) has emerged as a tool to identify these deficits.

PURPOSE

To review the reliability of the YBT-LQ, determine if performance on the YBT-LQ varies among populations (i.e., sex, sport/activity, and competition level), and to determine the injury risk identification validity of the YBT-LQ based on asymmetry, individual reach direction performance, or composite score.

STUDY DESIGN

Systematic Review.

METHODS

A comprehensive search was performed of 10 online databases from inception to October 30, 2019. Only studies that tested dynamic single leg balance using the YBT-LQ were included. Studies were excluded if the Y-Balance Test kit was not utilized during testing or if there was a major deviation from the Y-Balance test procedure. For methodological quality assessment, the modified Downs and Black scale and the Newcastle-Ottawa Scale were used.

RESULTS

Fifty-seven studies (four in multiple categories) were included with nine studies assessing reliability, 36 assessing population differences, and 16 assessing injury prediction were included. Intra-rater reliability ranged from 0.85-0.91. Sex differences were observed in the posteromedial direction (males: 109.6 [95%CI 107.4-111.8]; females: 102.3 [95%CI 97.2-107.4; p = 0.01]) and posterolateral direction (males: 107.0 [95%CI 105.0-109.1]; females: 102.0 [95%CI 97.8-106.2]). However, no difference was observed between sexes in the anterior reach direction (males: 71.9 [95%CI 69.5-74.5]; females: 70.8 [95%CI 65.7-75.9]; p=0.708). Differences in composite score were noted between soccer (97.6; 95%CI 95.9-99.3) and basketball (92.8; 95%CI 90.4-95.3; p <0.01), and baseball (97.4; 95%CI 94.6-100.2) and basketball (92.8; 95%CI 90.4-95.3; p=0.02). Given the heterogeneity of injury prediction studies, a meta-analysis of these data was not possible. Three of the 13 studies reported a relationship between anterior reach asymmetry reach and injury risk, three of 10 studies for posteromedial and posterolateral reach asymmetry, and one of 13 studies reported relationship with composite reach asymmetry.

CONCLUSIONS

There was moderate to high quality evidence demonstrating that the YBT-LQ is a reliable dynamic neuromuscular control test. Significant differences in sex and sport were observed. If general cut points (i.e., not population specific) are used, the YBT-LQ may not be predictive of injury. Clinical population specific requirements (e.g., age, sex, sport/activity) should be considered when interpreting YBT-LQ performance, particularly when used to identify risk factors for injury.

LEVEL OF EVIDENCE

1b.

Lateral Ankle Sprain and Subsequent Ankle Sprain Risk: A Systematic Review

OBJECTIVE

To evaluate the evidence regarding the association between lateral ankle sprain (LAS) history and the subsequent LAS risk, as well as sex differences in the observed associations.

DATA SOURCES

PubMed, CINAHL, and SPORTDiscus were searched through July 2020 for articles on LAS history and incidence during the study period.

STUDY SELECTION

Studies were included if they were prospective in nature and the authors reported the number of participants with and those without a history of LAS at study initiation as well as the number of participants in each group who sustained an LAS during the investigation.

DATA EXTRACTION

Data were study design parameters as well as the number of participants with and those without an LAS history and the number of subsequent LASs that occurred in both groups. Risk ratios (RRs) with 95% CIs compared the risk of LAS during the study period between those with and those without an LAS history for each investigation.

DATA SYNTHESIS

A total of 19 studies involving 6567 patients were included. The follow-up periods ranged from 14 weeks to 2 years. Assessment scores indicated the studies were of moderate to high quality. A significantly higher risk of LAS during the study period was observed among those with a history of LAS in 10 of 15 studies (RR range = 1.29-6.06). Similar associations were seen in 4 of 6 studies of all-male samples (RR range = 1.38-8.65) and 1 of 4 studies with an all-female sample (RR = 4.28).

CONCLUSIONS

Strong evidence indicates that a previous LAS increased the risk of a subsequent LAS injury. Men with a history of LAS appeared to be at a higher risk of sustaining a subsequent LAS, but women were not. However, further data are needed to draw definitive conclusions from the limited number of sex-specific studies.

Impact of Three Strengthening Exercises on Dynamic Knee Valgus and Balance with Poor Knee Control among Young Football Players: A Randomized Controlled Trial

The observed dynamic knee valgus and the limited dynamic balance described in the literature are modifiable risk factors for injuries in athletes. Therefore, identification and appropriate prevention are crucial in managing the development of young athletes. The aim of the study was to assess the effectiveness of three exercises strengthening the muscles: gluteal medius, popliteal and tibialis posterior to reduce dynamic knee valgus and improve the dynamic balance of the lower limbs in young football players with poor knee control. A total of 134 footballers were assessed for eligibility, and finally 45 participants (age 12–15) met the inclusion criteria. Participants were assessed with 2D video kinematic analysis during single-leg squats to assess the knee valgus angles and the dynamic balance (Y-Balance Test). No significant interactions between groups (Control and Exercise) and time (baseline and after 6 week) were noted for dynamic valgus for the left and right knee (p > 0.05). For the dynamic balance, there were statistically significant results, but not clinically relevant for anterior, posteromedial, and composite direction for the right lower limbs and for the anterior direction for left lower limbs in the exercise group. However, there were no significant differences (p > 0.05) in all of the YBT scores for both lower limbs between groups. This study demonstrated that there were no statistically significant differences in dynamic knee valgus angles and dynamic balance values after 6 weeks of exercise program in young footballers with poor knee control. Future randomized trials should focus on more comprehensive exercises, where possible using biofeedback methods to improve knee kinematics.

A Narrative Review of Limb Dominance: Task Specificity and the Importance of Fitness Testing

ABSTRACT

Virgile, A and Bishop, C. A narrative review of limb dominance: Task specificity and the importance of fitness testing. J Strength Cond Res 35(3): 846-858, 2021-Preferential limb function must be sustained through repetitious asymmetrical activities for continuous athletic development and, ultimately, optimal athletic performance. As such, the prevalence of limb dominance and between-limb differences is common in athletes. Severe between-limb differences have been associated with reductions in athletic performance and increased injury risk in athletes. However, in the current literature, the terms limb preference and limb dominance have been used interchangeably. Together, these terms include a limb that is subjectively preferred and one that is objectively dominant in 1 or more performance measures from a variety of athletic tasks. In this review, we (a) discuss reported correspondence between task-specific limb preference and limb dominance outcomes in athletes, (b) provide greater context and distinction between the terms limb preference and limb dominance, and (c) offer pragmatic strategies for practitioners to assess context-specific limb dominance. A limb that is subjectively preferred is not necessarily objectively dominant in 1 or more athletic qualities or sport-specific tasks. Further to this, a limb that is objectively superior in 1 task may not exhibit such superiority in a separate task. Thus, limb preference and limb dominance are both task-specific. As such, we propose that practitioners intentionally select tasks for limb dominance assessment which resemble the most relevant demands of sport. Because limb dominance profiles are inconsistent, we suggest that practitioners increase assessment frequency by integrating limb dominance testing into standard training activities. This will allow practitioners to better understand when changes reflect sport-specific adaptation vs. potential performance or injury ramifications.

Ankle Stability and Movement Coordination Impairments: Lateral Ankle Ligament Sprains Revision 2021

This revised clinical practice guideline (CPG) addresses the distinct but related lower extremity impairments of those with a first-time lateral ankle sprain (LAS) and those with chronic ankle instability (CAI). Depending on many factors, impairments may continue following injury. While most individuals experience resolution of symptoms, complaints of instability may continue and are defined as CAI. The aims of the revision were to provide a concise summary of the contemporary evidence since publication of the original guideline and to develop new recommendations or revise previously published recommendations to support evidence-based practice. J Orthop Sports Phys Ther 2021;51(4):CPG1-CPG80. doi:10.2519/jospt.2021.0302.

Does lower-limb asymmetry increase injury risk in sport? A systematic review

OBJECTIVE

The aim of this review was to synthesize the current understanding relating to the risks of lower body functional asymmetry with injury in athletic populations.

METHODS

An iterative data mining and sampling approach was used to construct a search phrase from key words, which were used to identify studies within SPORTdiscus, Medline and Academic Search Complete databases. Additional references were sourced from the reference lists of these articles.

RESULTS

After screening, 31 papers were reviewed, from an initial search identifying 302 possible studies. A total of 6228 participants were involved in the studies, of which soccer players were the most observed sporting demographic (n = 2171). Of the 31 studies reviewed eight found no statistical association between lower limb asymmetry and injury risk, 10 studies provided partial statistically significant evidence and a further 10 provided statistically significant statistical links.

CONCLUSION

Overall moderate to lower quality evidence for functional asymmetry as a risk factor for injury in sport was observed. While the possibility of a relationship between lower limb functional asymmetry and injury risk cannot be ruled out, further higher quality investigations, adopting standardised methodologies, is required.

Does Mental Fatigue Negatively Affect Outcomes of Functional Performance Tests?

PURPOSE

Mental fatigue impairs psychomotor skill performance by affecting visuomotor reaction time, accuracy, and decision-making. Recently, neurocognitive functional performance tests (FPT) that integrate these outcomes have been developed. The aim of this study was to assess the effect of mental fatigue on traditional and neurocognitive FPT in healthy adults.

METHODS

Fourteen volunteers (four women; mean ± SD age, 22 ± 1 yr; height, 176.9 ± 8.4 cm; weight, 69.7 ± 10.4 kg) participated in a randomized counterbalanced crossover design. A 100% incongruent Stroop color word test of 90 min was used to induce mental fatigue and the control task encompassed watching a 90-min documentary. Traditional FPT comprised a single-leg hop for distance, countermovement jump, and Y-balance test, whereas the neurocognitive FPT encompassed the reactive balance test (RBT). All FPTs were evaluated pre-post the 90-min task. Mental fatigue was assessed using the Stroop task, visual analog scale for mental fatigue, and the Eriksen-Flanker task.

RESULTS

Mental fatigue was successfully induced, as shown by a significant increase in visual analog scale for mental fatigue (P < 0.001), with no decrease in performance on the Stroop and Eriksen-Flanker task. No interaction effect of mental fatigue was found for the Y-balance test, single-leg hop, and countermovement jump. For the RBT accuracy, a significant interaction effect of mental fatigue and time was observed (P = 0.024), with participants performing significantly worse when mentally fatigued. No interaction effect or main effect of condition and time was observed when considering the effect of mental fatigue on visuomotor reaction time in the RBT.

CONCLUSIONS

Mental fatigue negatively affects a neurocognitive FPT, indicated by a decreased accuracy in response to visual stimuli in the RBT. Traditional FPT remained unaffected by mental fatigue.

The Relationship between Dynamic Balance and Jumping Tests among Adolescent Amateur Rugby Players. A Preliminary Study

Rugby is a demanding contact sport. In light of research, poor balance, reduced jumping ability, muscle strength, and incorrect landing patterns might contribute to the increased risk of injury in athletes. Investigating the relationship between tests assessing these abilities might not only allow for the skillful programming of preventive training but also helps in assessing the risk of injury to athletes. Thus, the main purpose of this study was to investigate the relationship between dynamic balance, vertical and horizontal jumps, and jump-landings movement patterns. Thirty-one healthy amateur adolescent rugby players (age: 14.3 ± 1.6 years, height 171.4 ± 9.7 cm, body mass 80 ± 26 kg) participated in the study. Data were collected by the Y-balance Test (YBT), Counter Movement Jump (CMJ), Single Leg Hop for Distance (SLHD), and Landing Error Score System (LESS). Significant positive correlations were found between SLHD both legs (SLHDb) and YBT Composite both legs (COMb) (r = 0.51, p = 0.0037) and between SLHDb and CMJ (r = 0.72, p < 0.0001). A relationship was also observed between the CMJ and YBT COMb test (r = 0.51, p = 0.006). Moderate positive correlations were found between the dominant legs in SLHD and the posterolateral (r = 0.40, p = 0.027), posteromedial (r = 0.43, p = 0.014), and composite (r = 0.48, p = 0.006) directions of the YBT. These results indicate that variables that are dependent on each other can support in the assessment of injury-risk and in enhancing sports performance of young athletes.

Effects of a 10 vs. 20-Min Injury Prevention Program on Neuromuscular and Functional Performance in Adolescent Football Players

Background

Regular injury prevention training is not only effective in reducing sports injury rates, but also in improving neuromuscular and performance-related variables. However, it is currently unknown if this effect can be modified by varying the training dosage.

Objective

To compare the effects of two injury prevention programmes with a different training duration on neuromuscular control and functional performance in adolescent football players.

Methods

342 (15.4 ± 1.7 years) male football players from 18 teams were initially included. The teams were cluster-randomized into two intervention groups. Both groups performed an injury prevention program twice a week during one football season (10 months) using the same exercises but a different duration. One intervention group (INT10, n = 175) performed the program for 10 min, while the other intervention group (INT20, n = 167) for 20 min. At the beginning and end of the season, balance control (Balance Error Scoring System = BESS), jump performance (Squat Jump, Countermovement Jump) and flexibility (Sit and Reach Test, ankle flexibility, hip flexibility) tests were performed. For the final analysis, nine teams with 104 players were considered.

Results

Significant group by time interactions were found for the sit and reach test (p < 0.001) and ankle flexibility (p < 0.001) with higher improvements in the INT20 group. Improvements over the period of one season but no group differences were found for the BESS, Squat Jump and hip flexibility.

Conclusion

Within a single training session, performing structured neuromuscular training with a longer duration is more effective than a shorter duration for improving lower extremity flexibility.

Effects of an 8-week basketball-specific proprioceptive training with a single-plane instability balance platform

BACKGROUND

To avoid injuries in basketball players, they are recommended to pay more attention to improve their body balance. Therefore new training methods and equipment need to be devised. This study examined the effects of an 8-week basketball-specific proprioception training program while using a new developed one plane instability balance board during warm-up for improving balance ability in basketball players. Players who obtained basketball-specific balance training were compared to a control group.

METHODS

Thirty-one male university basketball players (age: 21.35, SD = 0.605 years; height: 190.97, SD = 1.88; body mass: 86.95, SD = 2.61) participated in this study. Seventeen participants were assigned to the basketball-specific 8-week balance training group (BTG) while 14 participants served as a control group (CG). Both groups were tested with the Y balance test (YBT) and postural stability test (PST) at baseline and 8 weeks later.

RESULTS

The results indicate significant improvements in the overall YBT for both legs in BTG, but not in CG. However, no group differences were found for dynamic balance performance, but static balance (i.e., postural stability) differed between groups after 8 weeks. A statistically significant moderate inverse correlation was computed between the total score of YBT and the total score of the overall stability index (r=-0.404; p= 0.041).

CONCLUSIONS

An 8-week basketball-specific proprioception training program with a single-plane instability balance platform improved balance ability (Y balance test and postural stability test) of basketball players.

Identification of Ankle Injury Risk Factors in Professional Soccer Players Through a Preseason Functional Assessment

Background

Etiologically, the risk of an ankle injury depends on extrinsic and intrinsic factors, such as muscle strength asymmetry, decreased flexibility, and decreased proprioception, as well as patient age and history of injuries.

Purpose/Hypothesis

The purpose of this study was to identify risk factors present in the preseason assessment that may predispose professional soccer players to ankle injuries. We hypothesized that analysis of these parameters could relate the incidence of injuries to the deficits found during the preseason period, enabling the identification of risk factors to predict the occurrence of injuries.

Study Design

Cohort study; Level of evidence, 2.

Methods

A total of 89 professional soccer athletes were evaluated in the preseason period; the evaluation included athlete history and anthropometric data collection, an isokinetic ankle evaluation, and functional tests: the Dorsiflexion Lunge Test and Y-Balance Test (YBT). The athletes were monitored during the competitive period, and the incidence of injuries was surveyed. The association of quantitative variables and injury outcomes was analyzed using the Student t test for independent samples, with P < .05. For the association of categorical variables and injury outcomes, the chi-square test was performed, with P < .05.

Results

A higher incidence of ankle injuries was associated with lower YBT scores in the dominant (P = .04) and nondominant (P = .01) limbs. A higher body mass index was also associated with a higher injury occurrence (P = .01).

Conclusion

Functional tests, such as the YBT, are indicated tools for assessing the physical capacities and possible risks of ankle sprains, as they can evaluate the ankle functional capacity in a complex way, identifying athletes more prone to ankle injuries. Athletes' body mass index should also be taken into account to prevent such injuries.