Collegiate Soccer Athletes Research Articles

The Effect Of Playing Surface On Anterior Cruciate Ligament Injury In NCAA Soccer

Objectives: Previous orthopaedic literature has examined the effect of synthetic playing surfaces on the risk of anterior cruciate ligament (ACL) injury in athletes and produced varying and inconclusive results. The objective of this study was to examine the role of playing surface on the incidence and risk of ACL injury in collegiate soccer athletes. Methods: The NCAA Injury Surveillance Program (ISP) database was queried for ACL injuries for male and female soccer players from the 2004-05 through the 2013-14 seasons at all levels of competition. The number of athlete exposures (AEs), defined as 1 athlete participating in 1 practice or competition in which they were exposed to the possibility of athletic injury, were recorded for grass and synthetic playing surfaces. Both the reported injuries and exposures provided were weighted in order to represent the entire NCAA collegiate soccer population. Normalized ACL incidence rates were calculated as well as 95% confidence intervals (95%CI). Rate ratios comparing competition type amongst both competition and practice were calculated. Results: ACL injuries were more common on grass surfaces (1.16 per 10,000 AEs, 95%CI 1.12-1.20) than artificial turf (0.92 per 10,000 AEs, 95%CI 0.84-1.04). This difference was statistically significant (IRR 1.26, p<0.0001), and driven primarily by the difference in injury incidence during practice. The injury incidence during practice on natural grass (1.18 per 10,000 AEs, 95% CI 1.11-1.26) was significantly greater than the injury incidence rate during practice on artificial turf (0.067 per 10,000 AEs, 95%CI 0.043-0.096). Players were 17.7 times more likely (95%CI 10.6678-27.2187, p<0.0001) to sustain an ACL injury during practice on natural grass when compared to practice on artificial turf. However, there was no significant difference in injury incidence during matches (IRR 0.96, p=0.44), with matches on natural grass (3.35 per 10,000 AEs, 95% CI 3.21-3.51) equivalent to matches on artificial surfaces (3.49 per 10,000 AEs, 95%CI 3.18-3.81). When comparing exposure type, the injury rate was significantly greater during matches (3.38 per 10,000 AEs, 95% CI 3.25-3.52) compared to practices (0.82 per 10,000 AEs, 95%CI 0.77-0.88), with a 4.10-fold increase in ACL injury incidence during matches compared to practice (p<0.0001). Conclusion: Between 2004 and 2014, NCAA soccer players experienced a greater number of ACL injuries on natural grass playing surfaces compared with artificial turf playing surfaces. This difference is driven by injuries during practice, where athletes were nearly 18 times more likely to suffer an ACL injury on grass versus artificial turf. While ACL injuries were more likely during matches compared to practices, no difference in incidence was noted between playing surfaces. Additional study is warranted investigating potential causes for this observed increased risk with soccer practice on grass fields.

Sex differences in mechanisms of head impacts in collegiate soccer athletes

BackgroundThere has been growing interest in head impacts related to sports participation due to potential long- and short-term consequences of head injuries. Our purpose was to compare head impact magnitude and frequency between men's and women's intercollegiate soccer players based on head impact mechanism. Methods28 collegiate soccer players (16 women: age = 19.94 (1.06) years, height = 163.75 (5.15) cm, mass = 61.21 (5.09) kg; 12 men: age = 20.25 (1.14) years, height = 180.34 (6.03) cm, mass = 74.09 (9.32) kg) wore xPatch (X2 Biosystems, Seattle, WA) head impact sensors. Each practice and game was video recorded in order to confirm head impacts. The independent variable was impact mechanism (head to head, head to body (other than head), head to ground, ball to head, goal to head, and combination). Sensors collected linear and rotational accelerations and frequency of head impacts per 1000 athlete exposures. FindingsMen were more likely to sustain head impacts than women (IRR = 1.74, CI95 = 1.59–1.92). The highest head impact incidence rate for men was head to body (IR = 611.68, CI95 = 553.11–670.25) while the highest impact incidence rate for women was ball to head (IR = 302.29, CI95 = 270.93–333.64). The interaction between sex and mechanism was significant for rotational accelerations (F4, 1720 = 3.757, P = .005, ω2 = 0.013) but not for linear accelerations (F4,1720 = 0.680, P = .606, ω2 < 0.001, 1 − β = 0.223). InterpretationTo reduce the frequency of head impacts in men, perhaps rules governing player to player contact should be more strictly enforced as these data confirm frequent player-to-head contact during soccer practices and games. Prevention efforts for women should be focused on limiting the amount of purposeful heading (planned contact between the head and ball) occurring during play especially since these impacts had higher magnitudes compared to men.

Superficial heat administration and foam rolling increase hamstring flexibility acutely; with amplifying effects

ObjectivesTo compare the objective and subjective efficacy of three treatments on acute hip-flexion range of motion (ROM). DesignAssessor-blind, randomized within-subject cross-over. SettingUniversity athletic training clinic. ParticipantsTwenty-two female collegiate lacrosse and soccer athletes. Main outcome measuresThe passive straight-leg-raise (PSLR) was used to measure acute hip-flexion ROM pre- and post foam rolling (FR), superficial heating (SH), combination (SH + FR) and control treatments. A seven-point Likert scale statement measured the perceived effectiveness of each treatment. ResultsSuperficial heat (+10.4%, ES = 0.78), FR (+7.26%, ES = 0.52), and SH + FR treatment (+12.9%, ES = 1.26) improved hip ROM when compared to the control (+2.4%, ES = 0.24) (all p < 0.001). The SH + FR treatment resulted in a greater improvement in hip ROM compared to FR (p = 0.001, ES = 0.95), whereas no significant difference was observed between the SH and FR (p = 0.083, ES = 0.68) or SH and SH + FR treatment (p = 0.270, ES = 0.43). SH + FR was perceived as more effective than FR (p = 0.033, ES = 1.21), but not SH (p = 0.193, ES = 0.63). However, only a moderately positive correlation (r = 0.508) between objective and subjective measures of hamstring flexibility was found. ConclusionsAll treatments significantly improve hamstring flexibility with SH + FR being the most effective. Rehabilitation professionals should practice caution when relying on athlete perception and should prescribe treatments on an individual basis.

Measuring the Impact of Corrective Exercises on Ankle Function in Collegiate Female Soccer Players

Injuries to the ankle joint in soccer athletes are extremely common. Twenty-two female collegiate soccer athletes performed ankle corrective exercises for 3 months to attempt to establish and maintain optimal ankle joint function. The corrective exercises were devised to improve ankle range of motion (ROM) and Star-Excursion Balance Test (SEBT) scores. Statistically significant improvements were seen in ankle ROM and in the SEBT for the posteromedial, posterolateral, and composite reach portions of the test; the anterior reach direction failed to show significant changes. These results have clinical implications which suggest that corrective exercises may promote optimal ankle joint function and potentially reduce the risk of injury to the ankle.

Relative Age Effects In Men’s Collegiate Soccer Are Influenced By Nationality, Position, Class, And Success

Relative age effects (RAEs) refer to an unequal birth-date distribution within cohort of individuals, typically due to selection bias. RAEs have been shown to exist in sports, specifically youth soccer and elite professional soccer. However, no study has assessed the prevalence of RAEs at the collegiate level. PURPOSE: To evaluate the existence of RAEs in Division I Men’s collegiate soccer. Additionally, the study assessed the impact of nationality, position, class, and post-season tournament qualification on the prevalence of RAEs. METHODS: Birth-dates from Division I Men’s collegiate soccer athletes (n=4,082) from the 2017-2018 season were categorized into calendar quarters (CQ1: January-March; CQ2: April-June; CQ3: July-September; and CQ4: October-December) and scholastic quarters (SQ1: September-November; SQ2: December-February; SQ3: March-May; and SQ4: June-August). All athlete birth-date distributions were compared with the expected birth-date distributions for the United States. All data were assessed using χ2 goodness of fit tests. RESULTS: International-born athletes (INT) displayed a significant (p<0.001) difference in birth-date distribution when assessed with calendar quarters, with an over-representation in CQ1 (31.2±2.8%) and an under-representation in CQ4 (20.0±2.4%). However, American-born athletes (USA) showed a significant difference (p<0.001) in birth-date distribution when assessed with scholastic quarters, with over-representation in SQ1 (27.6±1.6%) and an under-representation in SQ4 (23.0±1.5%). Furthermore, INT showed significant (p≤0.001) RAEs for midfielders and defenders, while USA showed significant RAEs midfielders (p=0.009) and goalkeepers (p=0.004). In terms of class, INT had significant (p≤0.045) RAEs for all classes, while USA had significant RAEs only for freshmen (p=0.001) and sophomores (p=0.007). All INT had significant (p≤0.003) RAEs regardless of tournament qualification; however, USA had significant RAEs only for non-tournament teams (p<0.001). CONCLUSION: Significant RAEs exist in Division I Men’s collegiate soccer; however, the presence of RAEs are influenced by nationality, position, class, and on-field team success. Coaches should be aware of RAEs during the recruitment process to avoid potential selection bias.

The Association between Dietary Protein Intake Frequency, Amount, and State of Energy Balance on Body Composition in a Women's Collegiate Soccer Team

The purpose of this cross-sectional study was to assess whether the amount and frequency of dietary protein intake, and the state of energy balance when consumed, are associated with body composition of collegiate women's soccer athletes.

Changes in functional connectivity are associated with one season of head-to-ball impact exposure in male collegiate soccer athletes

ObjectivesReturn-to-play protocols could be improved by a better understanding of the physiologic effects of mild traumatic brain injury (mTBI). Autonomic dysregulation is thought to underlie many of the multi-dimensional symptoms following mTBI and may derive from altered connectivity in the brain central autonomic network (CAN). Understanding the relationship between injury and CAN connectivity could lead to a useful biomarker for mTBI. Toward this end, the present study aimed to establish a formal relationship between non-symptomatic head-to-ball impacts (“headers”) and CAN connectivity in collegiate soccer athletes.MethodsEleven male NCAA Division I soccer players were monitored by athletic training staff throughout 1 season for the number of headers. Ten male NCAA Division I athletes (3 cross-country and 7 golfers) served as controls. All participants underwent resting-state fMRI pre- and post-season. Twenty ROIs were selected based on regions previously implicated in control and modulation of autonomic function. Graph theoretical analyses were used to probe changes in network architecture and connectivity. Specific contrasts focused on pre- and post-season changes that were explained by individual differences in exposure to headers (p &lt; 0.05 uncorrected).ResultsWithin the 20 node network, increases in headers were associated with reduced degree centrality of the left and right insular cortex and right putamen (p&lt; 0.02), increased degree and betweenness centrality in the left anterior and right posterior Para hippocampal gyri (p&lt; 0.03), and increased betweenness centrality in the anterior cingulate cortex (p = 0.006). Headers were also associated with reduced functional connectivity within the subnetwork including the anterior cingulate cortex (p = 0.0073), right hippocampus, left putamen, and left insular cortex (p&lt; 0.04).ConclusionHighly skilled soccer players who sustained the greatest number of head impacts also experienced the greatest altered connectivity among regions associated with autonomic function. Future work to establish autonomic function as an injury biomarker should consider the importance of cumulative impact magnitudes.

Scaling isometric mid-thigh pull maximum strength in division I Athletes: are we meeting the assumptions?

ABSTRACT This study examined the validity of various scaling methods, isometric mid-thigh pull (IMTP) peak force using various scaling methods, and the relationships between IMTP peak force and countermovement jump height. Fifty-one collegiate baseball and soccer athletes performed two maximal IMTPs. Absolute peak force was compared between teams and when data were scaled using ratio (RS), traditional allometric (ALLOTrad), and fitted allometric (ALLOFit) scaling. ALLOTrad and ALLOFit validity was violated because different derived exponents existed for baseball (b = 0.20) and soccer (b = 1.20). Soccer athletes produced greater RS peak force compared to baseball (p = 0.012), while no difference existed with absolute, ALLOTrad or ALLOFit (all p > 0.05) peak force. Moderate relationships existed between body mass and absolute (r = 0.402, p = 0.003) and RS (r = -0.328, p = 0.019) peak force, while trivial relationships existed with ALLOTrad and ALLOFit (both r < -0.10, p > 0.05). Trivial relationships existed between countermovement jump height and absolute, RS, ALLOTrad, and ALLOFit (all r < 0.20, p > 0.05) peak force. The current dataset violated allometric scaling assumptions, making it inappropriate to use ALLOTrad and ALLOFit scaling. Practitioners must understand the assumptions, limitations, and purpose of scaling methods.

Quantifying Changes in Squat Jump Height Across a Season of Men's Collegiate Soccer.

Sams, ML, Sato, K, DeWeese, BH, Sayers, AL, and Stone, MH. Quantifying changes in squat jump height across a season of men's collegiate soccer. J Strength Cond Res 32(8): 2324-2330, 2018-The purposes of this study were to examine the effectiveness of an athlete monitoring program in managing athlete neuromuscular fatigue across a men's collegiate soccer season as measured by changes in squat jump (SJ) height and to compare possible changes with the session rating of perceived exertion (sRPE) training load (TL). Eighteen outfield Division I men's college soccer players performed SJ testing before each game of the fall season in addition to a baseline measurement at the start of preseason. The athletes provided sRPE values after all training sessions, weight-training, and games. Linear mixed modeling was used to compare changes in SJ height across the season with the baseline, and a correlation coefficient and single-lag cross-correlation coefficient were calculated between TL and changes in SJ height. No statistically significant decreases in SJ height occurred across the season, although a moderate practical decline occurred after the preseason (-1.6 cm, effect size = -0.70). The correlation between TL and changes in SJ height was statistically nonsignificant, whereas the cross-correlation was significant (r = 0.18, p = 0.48 and r = 0.55, p = 0.02, respectively). The athlete monitoring program was successful in managing the athletes' neuromuscular fatigue across the season as evidenced by the maintenance of SJ height and positive relationship between TL and changes in SJ height. Thus, SJ monitoring may serve as a useful fatigue monitoring tool for collegiate soccer athletes. Future study is needed, relating changes in vertical jump performance to other markers of athlete preparedness and performance.

Interest in Virtual Reality for Injury Rehabilitation and Performance Enhancement Among Collegiate Soccer Athletes

Interventions using virtual reality (VR) in three or two-dimensional, multi-sensory, synthetic worlds have been used to enhance rehabilitation and performance (e.g., combat PTSD in military personal, increase motor control in stroke-recovery patients). VR also has potential as a method for rehabilitation from sporting injuries. PURPOSE: To assess athletes’ interest in VR as an intervention to enhance performance and injury rehabilitation, and to identify preferred components within a VR world. We also explored gender influences on these preferences. We focused on one collegiate sport, soccer, at three levels (NCAA, NAIA, Junior College). METHODS: Sixty-eight collegiate soccer (25 male; 43 female) athletes completed an electronic survey which included demographics, as well as the virtual reality interest survey created to assess VR use, interest and specific factors athletes may find useful in a VR environment. RESULTS: Participants’ responses on a 10-point Likert-type scale from not interested (1) to extremely interested (10), indicated strong interest in using VR, both in recovery from injury (M=7.06, SD=2.67), and to improve sport performance (M=7.89, SD=2.59). Additional items asked about interest in specific forms of VR with the same 10-point response scale. Athletes indicated strong interest in viewing sport-specific scenarios (M=7.26, SD= 2.66), sport-specific skills (M=6.89, SD=2.73), and physically touching a soccer ball while submerged in a virtual world (M=6.89, SD=2.83). Other items, such as seeing a crowd in the stands, presence of an avatar coach, or viewing a teammates perform a sport skill unsuccessfully, were rated of less interest. In terms of gender, men were more interested than women in using VR both for injury recovery (Male: M=8.24, SD=2.18; Female: M=6.34, SD=2.70) and to enhance performance (Male: M=9.00, SD=1.84; Female: M=7.21, SD=2.77) CONCLUSION: VR interest is high among collegiate soccer athletes, both for injury recovery and performance enhancement. The athletes were particularly interested in a VR environment that incorporates sport-specific scenarios and physically touching a soccer ball. Men had stronger interests in VR, but both men and women athletes at all levels indicated interest in engaging in VR to assist in injury recovery and performance enhancement.

Increased Leg Bone Mineral Density and Content During the Initial Years of College Sport

Scerpella, JJ, Buehring, B, Hetzel, SJ, and Heiderscheit, BC. Increased leg bone mineral density and content during the initial years of college sport. J Strength Cond Res 32(4): 1123-1130, 2018-Bone mineral density (BMD) and bone mineral content (BMC) data are useful parameters for evaluating how training practices promote bone health. We used dual-energy X-ray absorptiometry (DXA) to longitudinally assess sport-specific growth in leg and total body BMD/BMC over the initial 2 years of collegiate training. Eighty-five Division 1 collegiate basketball, hockey, and soccer athletes (50 males and 35 females; age 19.0 [0.8] years) underwent annual DXA scans. Leg and total body BMD/BMC were compared within and across two 1-year intervals (periods 1 and 2) using repeated-measures analysis of variance, adjusting for age, sex, race, and sport. Leg BMD, leg BMC, and total body BMC all increased over period 1 (0.05 g·cm [p = 0.001], 0.07 kg [p = 0.002], and 0.19 kg [p < 0.001] respectively). Changes in period 2 compared with period 1 were smaller for leg BMD (p = 0.001), leg BMC (p < 0.001), leg fat mass (p = 0.028), and total BMC (p = 0.005). Leg lean mass increased more during period 2 than period 1 (p = 0.018). Sports participation was the only significant predictor of change in leg BMD. Significant increases in both leg BMD and BMC were demonstrated over both 2-year periods, with greater gains during period 1. These gains highlight the importance of attentive training procedures, capitalizing on attendant physical benefits of increased BMD/BMC. Additional research in young adults, evaluating bone mass acquisition, will optimize performance and decrease risk of bone stress injury among collegiate athletes.

Linear Acceleration in Direct Head Contact Across Impact Type, Player Position, and Playing Scenario in Collegiate Women's Soccer Players

Heading, an integral component of soccer, exposes athletes to a large number of head impacts over a career. The literature has begun to indicate that cumulative exposure may lead to long-term functional and psychological deficits. Quantifying an athlete's exposure over a season is a first step in understanding cumulative exposure. To measure the frequency and magnitude of direct head impacts in collegiate women's soccer players across impact type, player position, and game or practice scenario. Cross-sectional study. National Collegiate Athletic Association Division I institution. Twenty-three collegiate women's soccer athletes. Athletes wore Smart Impact Monitor accelerometers during all games and practices. Impacts were classified during visual, on-field monitoring of athletic events. All direct head impacts that exceeded the 10 g threshold were included in the final data analysis. The dependent variable was linear acceleration, and the fixed effects were (1) type of impact: clear, pass, shot, unintentional deflection, or head-to-head contact; (2) field position: goalkeeper, defense, forward, or midfielder; (3) playing scenario: game or practice. Shots (32.94 g ± 12.91 g, n = 38; P = .02) and clears (31.09 g ± 13.43 g, n = 101; P = .008) resulted in higher mean linear accelerations than passes (26.11 g ± 15.48 g, n = 451). Head-to-head impacts (51.26 g ± 36.61 g, n = 13; P < .001) and unintentional deflections (37.40 g ± 34.41 g, n = 24; P = .002) resulted in higher mean linear accelerations than purposeful headers (ie, shots, clears, and passes). No differences were seen in linear acceleration across player position or playing scenario. Nonheader impacts, including head-to-head impacts and unintentional deflections, resulted in higher mean linear accelerations than purposeful headers, including shots, clears, and passes, but occurred infrequently on the field. Therefore, these unanticipated impacts may not add substantially to an athlete's cumulative exposure, which is a function of both frequency and magnitude of impact.

Breast Injuries in Female Collegiate Basketball, Soccer, Softball and Volleyball Athletes: Prevalence, Type and Impact on Sports Participation.

In 2015-2016, over 214,000 female athletes competed at the collegiate level in the United States (U.S.). The National Collegiate Athletic Association (NCAA) collects injury data; however, breast-related injuries do not have a specific reporting category. The exact sequelae of breast injury are unknown; however, a relationship between breast injury and fat necrosis, which mimics breast carcinoma, is documented outside of sports participation. Breast injuries related to motor vehicle collisions, seatbelt trauma, and blunt trauma have been reported. For these reasons, it is important to investigate female breast injuries in collegiate sports. The objectives of this study are to report the prevalence of self-reported breast injuries in female collegiate athletes, explore injury types and treatments, and investigate breast injury reporting and impact on sports participation. A cross-sectional study of female collegiate athletes at four U.S. universities participating in basketball, soccer, softball, or volleyball. Main outcome measure was a questionnaire regarding breast injuries during sports participation. Almost half of the 194 participants (47.9%) reported a breast injury during their collegiate career, less than 10% reported their injury to health personnel with 2.1% receiving treatment. Breast injuries reported by breast injuries reported by sport include softball (59.5%), basketball (48.8%), soccer (46.7%), and volleyball (34.6%). The long-term effects and sequelae of breast injuries reported by female collegiate athletes during sport play are unknown. Nearly 50% of participants had a breast injury during sports activities. Although 18.2% indicated that breast injury affected sports participation, only 9.6% of the injuries were reported to medical personnel with 2.1% receiving treatment.

Gender-specific Lower Extremity Kinematic Differences in Collegiate Soccer Athletes during Three Kicking Tasks

Gender-specific Lower Extremity Kinematic Differences in Collegiate Soccer Athletes during Three Kicking Tasks

Balance Performance as Observed by Center-of-Pressure Parameter Characteristics in Male Soccer Athletes and Non-Athletes.

Static balance has a relevant influence on athletic performance as well as on reducing the risk of injury. The main goal of this study was to assess soccer athlete versus non-athlete balance performance via displacement and velocity parameters extracted from the center-of-pressure (COP) position time series. In order to accomplish our goal, we investigated standing balance in two male groups with unimpaired balance: non-athletes (n = 12) and collegiate varsity soccer athletes (n = 12). In order to make the standing balancing task more or less difficult, we altered participant base-of-support, as well as vision, yielding static (quiet stance) test conditions increasing in difficulty. From the COP position time series, displacement and velocity parameters were computed and plotted as a function of increasing test condition difficulty level. COP parameters showed steeper increases with increased test difficulty in non-athletes compared to athletes; this demonstrated athletes’ better ability to control their balance. We concluded that balance performance could be characterized via COP displacement and velocity response curves. This study lends new insights into how COP parameters can be utilized to determine and characterize improvements in balance between un-impaired subject populations (athletes versus non-athletes).

Body Composition Changes In Female Collegiate Soccer Athletes From Preseason To Postseason

Body Composition Changes In Female Collegiate Soccer Athletes From Preseason To Postseason

Biomechanical differences related to leg dominance were not found during a cutting task.

Previous studies have shown conflicting information regarding leg dominance as an etiological factor for the risk of anterior cruciate ligament (ACL) injuries. It remains unclear if lower extremity neuromechanical limb asymmetries exist in experienced athletes. The purpose of this study was to evaluate lower extremity neuromechanical effects of leg dominance in female collegiate soccer athletes during an unanticipated side-step cutting task. Twenty female collegiate soccer players completed an unanticipated side-step cutting task, using their dominant and non-dominant legs. Kinematic and kinetic data were collected to quantify joint angles and forces, with wireless electromyography (EMG) quantifying muscle activity. MANOVA's were conducted to determine the effect of leg dominance on hip and knee mechanics at and between pre-contact, initial contact, peak knee adduction moment, and peak stance periods. Dependent variables consisted of peak time occurrences, hip and knee rotations and moments, ground reaction force, EMG amplitudes, stance time, and approach velocity. No significant differences were found for any variables at or between the periods of interest. Collegiate female soccer athletes exhibit similar movement patterns between dominant and non-dominant legs while performing a side-step cutting task, suggesting that leg dominance does not adversely influence known biomechanical non-contact ACL risk factors.

Normalizing VO2max to Body Composition Eliminates Gender Differences in Collegiate Soccer and Hockey Athletes

Normalizing VO2max to Body Composition Eliminates Gender Differences in Collegiate Soccer and Hockey Athletes

The Relationship between Anthropometric Variables and Isokinetic Strength in a Women’s Collegiate Soccer Team

Knee isokinetic strength has been reported to be correlated with body fat, fat free mass, and BMI in college students. It is unclear if these anthropometric variables are related to isokinetic performance in relatively homogeneous groups of athletes. PURPOSE: To investigate the relationship between common anthropometrics and average torque production of the knee extensors in a women’s collegiate soccer team. METHODS: Twenty-eight healthy female collegiate soccer athletes aged 18-22 years participated. The participants had no history of significant lower leg injuries. Participants were screened using standard anthropometric measurements that included: height, weight, and skinfold measures of the triceps, suprailiac, and thigh areas. The measurements allowed for calculation of the BMI, lean body mass, lean body mass index (LBMI), and body fat percentage. Isokinetic strength of knee flexion and extension was measured through three angular velocities of 60, 180, and 300 degrees/sec. The relationships between the anthropometric measurements (height, weight, BMI, lean body mass, LBMI, body fat percentage) and average peak torques at the three angular velocities were assessed utilizing hierarchal linear regression and bivariate correlation coefficients. RESULTS: Hierarchal linear regression revealed a significant relationship for average peak torque at 180 degrees/sec, (F = 3.994 (3, 24); p = .019), with BMI, lean body mass, and body fat as the predictors. Further analysis utilizing Pearson’s bivariate correlation coefficient matrix found moderate correlations between average peak torque and BMI (.362 to .557; p<.05), lean body mass (.404 to .425; p<.05), and LBMI (.376 to .413; p<.05). CONCLUSION: The results found in this athletic population differ from previous research involving physically active nonathletes of a similar age. While anthropometric measures have been reported to be related to isokinetic knee strength in nonathletes, in this athletic population the relationship varied depending on the angular velocity. The results suggest that anthropometric measurements such as height, weight, BMI, lean body mass, LBMI, and body fat percentage may not be strong predictors of isokinetic knee muscle strength across angular velocities in an athletic population.

Cross-cultural adaptation, reliability, and validity of the Japanese version of the Cumberland ankle instability tool

Purpose To study validity and reliability of a Japanese version of the Cumberland Ankle Instability Tool and to determine the optimal cutoff score. Methods In this study, the questionnaire was cross-culturally adapted into Japanese. The psychometric properties tested in the Japanese version of the CAIT were measured for criteria validity, internal consistency and test–retest reliability in 111 collegiate soccer athletes. We also established the questionnaire cutoff score for discriminating between individuals with and without CAI. Results There was a significant correlation between the Japanese version of the CAIT and the Karlsson score (r = 0.604, p < 0.001). The questionnaire had a high internal consistency (Cronbach’s α = 0.833) and reliability [intraclass correlation coefficient (ICC) = 0.826, 95% confidence interval (CI): 0.732–0.888]. The optimal cutoff score was ≤25, which was consistent with previous reports. Conclusions The Japanese version of the CAIT has been shown to be a valid and reliable questionnaire for determining the presence of CAI. We expect that researchers and clinicians will use the Japanese version of the CAIT in Japan.Implications for RehabilitationChronic Ankle Instability (CAI), which not only increases recurrence rate of ankle sprain but also decreases athletic performance, is a residual symptom after ankle sprain.Cumberland Ankle Instability Tool, which has the reliability and validity to assess CAI, will be critically useful in assessment procedure for CAI.It is preferable for clinicians and researchers to use the native language version of the CAIT.