A Comparison of Machine versus Free-Weight Squats for the Enhancement of Lower-Body Power, Speed, and Change-of-Direction Ability during an Initial Training Phase of Recreationally-Active Women.

The purpose of this study was to examine differences between a free-weight squat (FWS) and machine squat (MS) during an initial resistance training phase for augmentation of performance tests in recreationally active women. Twenty-seven women (22.7 ± 3.5 years) were block-randomized to three groups: FWS, MS, or control (CON) and completed pre- and post-testing sessions consisting of the squat one-repetition maximum (1-RM), vertical jump, pro-agility test, zig-zag change-of-direction (COD) test, and 30-meter sprint. Participants trained two sessions per week for six weeks by performing jumping, sprinting, and COD drills followed by FWS, MS, or no squats (CON). Peak jump power increased for CON (p = 0.03) and MS (p < 0.01) groups. Change in peak jump power was greater for the MS group compared with the FWS group (p = 0.05). Average jump power increased for the MS group (p < 0.01). Change in average jump power was greater for the MS group compared with the CON group (p = 0.04). Vertical jump height, pro-agility, 30-meter sprint, and zig-zag COD tests improved over time (p < 0.01), with no difference between groups (p > 0.05). Machine squat training maximized jumping power compared with FWS training and CON. Both resistance training groups and the CON group improved equally in the pro-agility, 30-meter sprint, and zig-zag COD tests. Machine squat training may provide performance-enhancing benefits of equal or superior value to those obtained with free-weight squat training in recreationally active women during an initial training mesocycle. These findings also stress the importance of task-specific training in this population of untrained women, as the control group improved in terms of performance to the same degree as both resistance training groups.

Effect of Kinesio® Taping on Ankle Complex Motion and Stiffness and Jump Landing Time to Stabilization in Female Ballet Dancers.

Ankle sprain is the most commonly diagnosed injury experienced by ballet dancers with few studies investigating preventive support measures such as Kinesio taping. The need exists to examine the mechanical support characteristics of Kinesio taping and effect of application on ankle motion and performance. This may be important to understanding the mechanical mechanisms attributed to Kinesio ankle taping and justify its use in the prevention and treatment of jump landing injuries in ballet dancers. This study compared Kinesio taping with and without tension and no tape (control) on active and passive measures of ankle complex motion in healthy ballet dancers. A secondary objective was to examine the effect of Kinesio taping on balance using time to stabilization. Participants performed three ballet jumps with single-leg landings on a force plate across three ankle support conditions consisting of Kinesio taping, sham-Kinesio taping, and no tape. Sagittal and frontal plane motion and load-displacement of the ankle complex for each support condition were obtained using an ankle arthrometer. Kinesio taping with tension significantly restricted inversion-eversion rotation and increased inversion stiffness of the ankle complex (p < 0.05). No significant differences were found among the three ankle support conditions for jump landing time to stabilization (p > 0.05). Arthrometric results indicate Kinesio taping significantly restricted ankle complex motion in the frontal plane that is associated with lateral ankle sprain. Objective information on the nature of Kinesio taping support can assist sports medicine practitioners when recommending ankle support to athletes.

Does T'ai Chi Gait Reduce External Knee Adduction Moment?

INTRODUCTION: T'ai chi chuan is a beneficial exercise of improving health and function. Biomechanical insights of t'ai chi chuan are less understood. OBJECTIVES: To study t'ai chi gait (TCG), a common form of t'ai chi chuan in order to quantify external knee adduction moment (EKAM) as a key indicator of mechanical loading of the medial compartment of the knee compared with normal walking (NW). DESIGN: A quantitative biomechanics approach to determine peak EKAM for NW and TCG. RESULTS: There were a tri-modal pattern of EKAM during TCG and a bimodal pattern of EKAM during normal walking. In addition, subsequent analysis showed a 25%-47% reduction in peak EKAM during double support phases of TCG compared with NW; the peak EKAM of TCG during single-limb support phase showed significantly higher magnitude than the other two double-support phases. CONCLUSION: These results indicate that t'ai chi chuan might be a beneficial intervention for reducing the medial mechanical load at the knee joint, particularly during the first double-support phases of TCG, but the special consideration of higher peak EKAM of single-limb support phase is needed during regular t'ai chi chuan practice.

Joint stability characteristics of the ankle complex in female athletes with histories of lateral ankle sprain, part II: clinical experience using arthrometric measurement.

CONTEXT: This is part II of a 2-part series discussing stability characteristics of the ankle complex. In part I, we used a cadaver model to examine the effects of sectioning the lateral ankle ligaments on anterior and inversion motion and stiffness of the ankle complex. In part II, we wanted to build on and apply these findings to the clinical assessment of ankle-complex motion and stiffness in a group of athletes with a history of unilateral ankle sprain. OBJECTIVE: To examine ankle-complex motion and stiffness in a group of athletes with reported history of lateral ankle sprain. DESIGN: Cross-sectional study. SETTING: University research laboratory. PATIENTS OR OTHER PARTICIPANTS: Twenty-five female college athletes (age = 19.4 ± 1.4 years, height = 170.2 ± 7.4 cm, mass = 67.3 ± 10.0 kg) with histories of unilateral ankle sprain. INTERVENTION(S): All ankles underwent loading with an ankle arthrometer. Ankles were tested bilaterally. MAIN OUTCOME MEASURE(S): The dependent variables were anterior displacement, anterior end-range stiffness, inversion rotation, and inversion end-range stiffness. RESULTS: Anterior displacement of the ankle complex did not differ between the uninjured and sprained ankles (P = .37), whereas ankle-complex rotation was greater for the sprained ankles (P = .03). The sprained ankles had less anterior and inversion end-range stiffness than the uninjured ankles (P < .01). CONCLUSIONS: Changes in ankle-complex laxity and end-range stiffness were detected in ankles with histories of sprain. These results indicate the presence of altered mechanical characteristics in the soft tissues of the sprained ankles.

Joint stability characteristics of the ankle complex after lateral ligamentous injury, part I: a laboratory comparison using arthrometric measurement.

CONTEXT: The mechanical property of stiffness may be important to investigating how lateral ankle ligament injury affects the behavior of the viscoelastic properties of the ankle complex. A better understanding of injury effects on tissue elastic characteristics in relation to joint laxity could be obtained from cadaveric study. OBJECTIVE: To biomechanically determine the laxity and stiffness characteristics of the cadaver ankle complex before and after simulated injury to the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) during anterior drawer and inversion loading. DESIGN: Cross-sectional study. SETTING: University research laboratory. PATIENTS OR OTHER PARTICIPANTS: Seven fresh-frozen cadaver ankle specimens. INTERVENTION(S): All ankles underwent loading before and after simulated lateral ankle injury using an ankle arthrometer. MAIN OUTCOME MEASURE(S): The dependent variables were anterior displacement, anterior end-range stiffness, inversion rotation, and inversion end-range stiffness. RESULTS: Isolated ATFL and combined ATFL and CFL sectioning resulted in increased anterior displacement but not end-range stiffness when compared with the intact ankle. With inversion loading, combined ATFL and CFL sectioning resulted in increased range of motion and decreased end-range stiffness when compared with the intact and ATFL-sectioned ankles. CONCLUSIONS: The absence of change in anterior end-range stiffness between the intact and ligament-deficient ankles indicated bony and other soft tissues functioned to maintain stiffness after pathologic joint displacement, whereas inversion loading of the CFL-deficient ankle after pathologic joint displacement indicated the ankle complex was less stiff when supported only by the secondary joint structures.

Arthrometric measurement of ankle-complex motion: normative values.

CONTEXT: Valid and reliable measurements of ankle-complex motion have been reported using the Hollis Ankle Arthrometer. No published normative data of ankle-complex motion obtained from ankle arthrometry are available for use as a reference for clinical decision making. OBJECTIVE: To describe the distribution variables of ankle-complex motion in uninjured ankles and to establish normative reference values for use in research and to assist in clinical decision making. DESIGN: Descriptive laboratory study. SETTING: University research laboratory. PATIENTS OR OTHER PARTICIPANTS: Both ankles of 50 men and 50 women (age = 21.78 ± 2.0 years [range, 19-25 years]) were tested. INTERVENTION(S): Each ankle underwent anteroposterior (AP) and inversion-eversion (I-E) loading using an ankle arthrometer. MAIN OUTCOME MEASURE(S): Recorded anterior, posterior, and total AP displacement (millimeters) at 125 N and inversion, eversion, and total I-E rotation (degrees) at 4 Nm. RESULTS: Women had greater ankle-complex motion for all variables except for posterior displacement. Total AP displacement of the ankle complex was 18.79 ± 4.1 mm for women and 16.70 ± 4.8 mm for men (U = 3742.5, P < .01). Total I-E rotation of the ankle complex was 42.10 degrees ± 9.0 degrees for women and 34.13 degrees ± 10.1 degrees for men (U = 2807, P < .001). All variables were normally distributed except for anterior displacement, inversion rotation, eversion rotation, and total I-E rotation in the women's ankles and eversion rotation in the men's ankles; these variables were skewed positively. CONCLUSIONS: Our study increases the available database on ankle-complex motion, and it forms the basis of norm-referenced clinical comparisons and the basis on which quantitative definitions of ankle pathologic conditions can be developed.

Application of generalizability theory in estimating the reliability of ankle-complex laxity measurement.

CONTEXT: Generalizability theory is an appropriate method for determining the reliability of measurements obtained across more than a single facet. In the clinical and research settings, ankle-complex laxity assessment may be performed using different examiners and multiple trials. OBJECTIVE: To determine the reliability of ankle-complex laxity measurements across different examiners and multiple trials using generalizability theory. DESIGN: Correlational study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Forty male university students without a history of ankle injury. MAIN OUTCOME MEASURE(S): Measures of right ankle-complex anteroposterior and inversion-eversion laxity were obtained by 2 examiners. Each examiner performed 2 anteroposterior trials, followed by 2 inversion-eversion trials for each ankle at 0 degrees of ankle flexion. Using generalizability theory, we performed G study and D study analyses. RESULTS: More measurement error was found for facets associated with examiner than with trial for both anteroposterior and inversion-eversion laxity. Inversion-eversion measurement was more reliable than anteroposterior laxity measurement. Although 1 examiner and 1 trial had acceptable reliability (G coefficient >/= .848), increasing the number of examiners increased reliability to a greater extent than did increasing the number of trials. CONCLUSIONS: Within the range of examiner and trial facets studied, any combination of examiners or trials (or both) above 1 can change ankle laxity measurement reliability from acceptable (1 examiner, 1 trial) to highly reliable (3 examiners, 3 trials). Individuals may respond to examiners and their procedural nuances differently; thus, standardized procedures are important.

Survey of short-term oral corticosteroid administration by orthopaedic physicians in college and high school athletes.

The use of oral corticosteroid (OCS) drugs is advocated because of their potent anti-inflammatory effects. They also possess many potential adverse effects. No study has assessed physician prescribing practices of OCS therapy in high school (HS) or college (COL) athletes. This paper reports the prescribing patterns of sports medicine physicians who used short-term OCS therapy and to describe associated complications in HS and COL athletes within a 24- month period. An internet link to a descriptive epidemiology survey was included in an e-mail to all members of the Arthroscopy Association of North America and the American Orthopaedic Society for Sports Medicine. Descriptive statistics and correlation analysis were used to examine responses. Total response rate was 32% (615/1,928). Sixty-six percent of the physicians indicated prescribing OCS to both groups of athletes, while 29% reported prescribing OCS to COL athletes and 5% to HS athletes for musculoskeletal injuries. Physicians who prescribed multiple OCS regimens to the same athlete within the same season (P = 0.01) and physicians who prescribed OCS to the skeletally immature athlete (P = 0.009) reported more complications than other physicians. Among the 412 physicians who did not prescribe OCS in the treatment of athletic induced musculoskeletal injury, 251 (61%) cited a risk of developing medical complications as the primary reason for avoiding use. The reported number of medical complications was low with no cases of avascular necrosis reported for the 2-year recall period. Orthopaedic surgeons who treated athletic induced musculoskeletal injuries with a short-term course of oral corticosteroids reported that high school and college athletes benefited with few medical complications. Key pointsThirty-four percent of orthopaedic sports medicine physicians we surveyed reported prescribing a short-term course of oral corticosteroids for the treatment of an athletic-related musculoskeletal injury within the previous 24 months of answering the survey.The orthopaedic surgeons who treated athletic induced musculoskeletal injuries with a short-term course of OCS reported the high school and college athletes benefited from OCS treatment with few medical complications.Short-term oral corticosteroid use in multiple regimens in the same athlete and in the skeletally immature athlete may pose an increased risk of medical complication.

Knee and ankle position, anterior drawer laxity, and stiffness of the ankle complex.

CONTEXT: Anterior drawer testing of the ankle is commonly used to diagnose lateral ligamentous instability. Our hypothesis was that changing knee and ankle positions would change the stability of the ankle complex during anterior drawer testing. OBJECTIVES: To assess the effects of knee and ankle position on anterior drawer laxity and stiffness of the ankle complex. DESIGN: A repeated-measures design with knee and ankle position as independent variables. SETTING: University research laboratory. PATIENTS OR OTHER PARTICIPANTS: Bilateral ankles of 10 female (age = 19.8 +/- 1.1 years) and 10 male (age = 20.8 +/- 1.2 years) collegiate athletes were tested. INTERVENTION(S): Each ankle complex underwent loading using an ankle arthrometer under 4 test conditions consisting of 2 knee positions (90 degrees and 0 degrees of flexion) and 2 ankle positions (0 degrees and 10 degrees of plantar flexion [PF]). MAIN OUTCOME MEASURE(S): Recorded anterior laxity (mm) and stiffness (N/mm). RESULTS: Anterior laxity of the ankle complex was maximal with the knee positioned at 90 degrees of flexion and the ankle at 10 degrees of PF when compared with the knee positioned at 0 degrees of flexion and the ankle at 10 degrees or 0 degrees of PF (P < .001), whereas ankle complex stiffness was greatest with the knee positioned at 0 degrees of flexion and the ankle at 0 degrees of PF (P < .009). CONCLUSIONS: Anterior drawer testing of the ankle complex with the knee positioned at 90 degrees of flexion and the ankle at 10 degrees of PF produced the most laxity and the least stiffness. These findings indicate that anterior drawer testing with the knee at 90 degrees of flexion and the ankle at 10 degrees of PF may permit better isolation of the ankle capsuloligamentous structures.

The effects of repetitive overhead throwing on shoulder rotator isokinetic work-fatigue.

BACKGROUND: Muscle strength and endurance of the shoulder rotators is important for overhead throwing performance and dynamic glenohumeral stability. Baseball pitching is distinguished as an intermittent activity with explosive, high intensity muscle contractions separated by periods of rest. Rotator cuff muscle performance could acutely decrease due to fatigue associated with bouts of throwing. OBJECTIVE: This study examined the effects of repeated overhead throwing upon isokinetic muscle performance of the shoulder rotators. METHODS: Repeated-measures analyses of vari-ance were used to compare peak torque, total work, and work-fatigue by muscle group, time, and contraction type. Ten collegiate baseball pitchers underwent isokinetic testing of the internal (IR) and external shoulder (ER) rotators one week before and immediately after a throwing protocol of 60 maximal-effort pitches arranged into four innings of 15 pitches per inning. Isokinetic testing consisted of 12 concentric and eccentric repetitions at 300 deg/sec for internal and external rotation of the throwing extremity. RESULTS: The main effect of time and the interaction of muscle group and contraction type were significant for work-fatigue. Post-hoc analysis revealed that subjects had significantly greater eccentric IR work-fatigue (13.3 + 1%) compared to the pre-test (7.3 + 2%). DISCUSSION AND CONCLUSIONS: Throwing-related fatigue affected both muscle groups, especially the IR, which has implications for dynamic glenohumeral stability. Rehabilitation and conditioning programs for competitive baseball pitchers should emphasize eccentric muscle endurance training of the shoulder rotators.

Collegiate year of eligibility, sex, and sports achievement motivation.

The relations among year of eligibility, sex, and achievement motivation were investigated with 88 athletes representing three levels of collegiate eligibility (Year 1, Year 2/3, and Year 4) by sex. Participants were given Achievement Motivation subscales for Sporting Environments (approach-success practice, approach-success competition, failure-avoidance practice, failure-avoidance competition). A 3 x 2 analysis of variance showed significant main effects for year of eligibility and sex, and an interaction for age x sex for the failure-avoidance competition scores. Mean approach-success and failure-avoidance practice scores were not significantly different. Fear of failure may be less for male athletes in Year 4 of eligibility.

Effects of specific versus variable practice on the retention and transfer of a continuous motor skill.

The effects of specific versus variable practice on retention and transfer was investigated. 30 participants were randomly assigned to one of three practice conditions. The variable speed group practiced on a pursuit rotor task at three different speeds (60, 45, 30 rpm) which were randomly distributed but equal in number for 30 10-sec. trials on Day 1. The Specific Practice group performed all 30 10-sec. trials at 45 rpm on Day 1. On Day 2, all groups performed 15 trials at the 45-rpm retention speed and 15 trials at the 75-rpm transfer speed. The Control group only performed on Day 2. Analysis showed the Specific Practice group had significantly higher scores on Day 1. On Day 2, the Specific Practice group had significantly higher retention scores and the Variable Practice group had higher transfer scores. Continuous motor skills might be practiced differently depending on the environmental context in which the skill may be used.

Medicolegal issues affecting sports medicine practitioners.

The practice of sports medicine represents a unique subspecialty within the discipline of medicine. Practitioners provide care for athletes who engage in activities that may put the athletes at risk for serious injury. Physicians may be held legally liable for not doing a standardized pre-participation evaluation, for not administering adequate on-site or after injury care, or for violating an individual's civil rights by refusing to allow continued participation because of medical risk. The courts now are being asked to define obvious and necessary risks. Medical law addresses the behavior, obligation, and liability-affecting physicians who provide care for athletes. Many ethical and medicolegal issues must be resolved by the legal system because coaches, athletic trainers, on-call physicians, physicians providing pre-participation physicals, and the team physician are being held responsible for injuries sustained during athletic competition. This review is intended to assist all physicians who take care of athletes by outlining their legal obligations and risks. Armed with this knowledge, we expect that the sports medicine physician will be better able to focus on patient care within the context of medicolegal obligations.

Effects of the subtalar sling ankle taping technique on combined talocrural-subtalar joint motions.

BACKGROUND: The findings of research on the effectiveness of ankle taping for protection against ligament injury have been inconsistent, and the topic remains controversial. The precise orientation of the force vectors created by tension within the various tape strip components of an ankle taping procedure may be a critical factor influencing the degree of motion restraint that is provided. We hypothesized that the addition of the subtalar sling component to the widely recognized standard (Gibney) ankle taping procedure would enhance restraint of ankle motion. This was a controlled laboratory study, with fully repeated measures (subjects served as their own controls). METHODS: An ankle arthrometer was used to quantify anteroposterior (AP) translation and frontal plane inversion-eversion (I-E) tilt of the talocrural-subtalar joints under untaped and taped conditions in normal subjects. A 15-minute exercise session was conducted to loosen the tape before measurement of its effect on motion restraint. RESULTS: The ankle taping procedure that incorporated the subtalar sling provided significantly greater restriction of postexercise AP translation (p < 0.001, eta(2) = 0.63) and postexercise I-E tilt (p < 0.001, eta(2) = 0.66). CONCLUSIONS: The subtalar sling ankle taping procedure provides greater restriction of motions associated with ankle instability than the more widely used Gibney procedure.

Quantitative assessment of mechanical laxity in the functionally unstable ankle.

PURPOSE: Delineating between functional and mechanical instability in those with chronic ankle dysfunction is a challenging task. Current methods of assessing ankle ligamentous laxity are subjective in nature and limit our ability to identify the site and extent of instability; therefore, a need exists for objective laxity measurements. The purpose of this study was to determine whether subjects with self-reported, functional ankle instability (FAI) demonstrated increased mechanical laxity when tested with instrumented arthrometry and stress radiography. METHODS: Both ankles were tested in 51 subjects with self-reported unilateral FAI. An instrumented ankle arthrometer measured ankle-subtalar joint motion for total anteroposterior (AP) displacement (mm) during loading at 125 N and total inversion-eversion (I-E) rotation (degrees of ROM) during loading at 4 N x m. The Telos GA-II/E device provided either anterior or lateral stress (15 kp) while fluoroscopic radiographs were recorded for anterior displacement (mm) and talar tilt (degrees). RESULTS: The arthrometry measurements of anterior and total AP displacement and the radiographic measurements of anterior displacement were greater (P < 0.05) in the FAI ankles when compared with the uninjured ankles. There were no differences in total I-E rotation, inversion rotation, or talar tilt between ankles when analyzed with either measurement technique. CONCLUSION: The ability to objectively measure mechanical instability in the functionally unstable ankle is important to understanding the nature and cause of the instability. Ankle arthrometry and stress radiographic measurements are objective assessment tools for mechanical laxity. Despite finding greater laxity in the functionally unstable ankle, the clinical significance of the observed displacement remains unanswered. Further research is needed to determine the amount of laxity that constitutes mechanical instability and how this relates to FAI.

Sex and competitive status in ankle inversion-eversion range of motion of college students.

The effects of sex and competitive status (athlete vs nonathlete) on ankle inversion-eversion range of motion was investigated. 62 collegiate athletes and 36 collegiate nonathletes, both male and female, were tested. Analysis of variance showed significant (p<.05) main effects for sex but not competitive status or sex x competitive status. These results imply that college age women have more ankle rotational range of motion than men and that collegiate athletes in a group of various sports do not differ in ankle range of motion when compared to college nonathletes. Power in this sample did not permit definitive assessment.

Upper and lower body strength in relation to ball speed during a serve by male collegiate tennis players.

The relation of leg, shoulder, and grip strength to ball speed in the tennis serve was investigated. For 15 collegiate male tennis players, leg and shoulder strength were measured using a Lido Active isokinetic dynamometer, grip strength with a handgrip dynamometer, and ball speed with a radar gun. Regression analysis showed no significant (p<.05) relationship among the strength variables and ball speed. Results were explained in terms of strength not being the only factor involved in producing ball speed during the tennis serve.

Assessment of Ankle-Subtalar-Joint-Complex Laxity Using an Instrumented Ankle Arthrometer: An Experimental Cadaveric Investigation.

OBJECTIVE: To show the relationship between direct measurements of tibial-calcaneal bone motion and instrumented measurements of ankle-subtalar-joint-complex laxity using a portable ankle arthrometer; to assess within and between-tester measurement reliability; and to determine if the ankle arthrometer can detect increased mechanical laxity of the ankle-subtalar-joint-complex after simulated injury of the lateral ankle ligaments. DESIGN AND SETTING: We used linear regression analysis to examine the relationship between direct measurements of tibial-calcaneal bone motion and instrumented measurements of ankle-subtalar-joint-complex laxity. An intraclass correlation coefficient (2,1) was calculated to determine intratester and intertester reliability for instrumented measurements of ankle-subtalar-joint-complex laxity. In addition, 2 separate, one-way, repeated-measures analyses of variance were used to compare instrumented measures of anteroposterior displacement and inversion-eversion rotation among the intact ankles after sectioning the anterior talofibular ligament and both the anterior talofibular and calcaneofibular ligaments. Data were collected in a biomechanics laboratory setting. SUBJECTS: Six fresh-frozen human-cadaver ankle specimens were studied. MEASUREMENTS: Testing involved the concurrent measurement of tibial-calcaneal bone motion and ankle-subtalar-joint-complex motion during the application of external loads. An instrumented ankle arthrometer was used to load the ankle in a controlled manner. Two spatial kinematic linkages measured the 3-dimensional motion of the calcaneus relative to the tibia and the motion of the arthrometer's footplate relative to the tibia. RESULTS: The correlation between tibial-calcaneal bone motion and instrumented measurement for anterior-posterior displacement was.878 (P =.0001). Its linear relationship with bone motion accounted for approximately 77% of the variance of the instrumented measurement. The correlation between tibial-calcaneal bone motion and instrumented measurement for inversion-eversion rotation was.858 (P =.0001), with approximately 74% of the variance of the instrumented measurement accounted for by its linear relationship with bone motion. High intratester and intertester reliability coefficients (ICC [2,1] =.80 to.97) were observed for instrumented measurements of ankle-subtalar-joint-complex laxity. In addition, ligamentous sectioning resulted in significantly increased ankle-subtalar-joint-complex laxity. When compared with the intact condition, sectioning both the anterior talofibular and calcaneofibular ligaments produced significant increases in anterior-posterior displacement (P =.0001) and inversion-eversion rotation (P =.002). CONCLUSIONS: We found a strong relationship between tibial-calcaneal bone motion and arthrometric measurements of ankle-subtalar-joint-complex laxity. The instrumented ankle arthrometer may be suitable as a diagnostic tool for the evaluation of lateral ankle-ligament laxity.

Athletic Profile of Women College Volleyball Players.

Descriptive information about female athletes will help physicians, trainers, and coaches design conditioning programs and determine playing positions.