The purpose of this study was to provide an in-depth sports medicine profile of women college tennis players and determine the relationships among an array of performance and clinical variables. Thirty-eight non-resistance-trained women from NCAA Divisions I and III collegiate tennis teams participated. A comprehensive battery of performance tests was conducted on each subject, including measurements of dynamic, isometric, and isokinetic strength; joint laxity and flexibility; speed; agility; power and power endurance; peak oxygen consumption; body composition; and ball velocities of the serve, forehand, and backhand. It was found that no single variable strongly explains tennis performance. The low amount of shared variance of strength measures with ball velocities suggests that tennis skills play a large role in producing peak ball velocities in this group. Due to the large range observed in profiled variables, individual evaluation is needed for clinical and conditioning recommendations.
William J. Kraemer, N. Travis Triplett, Andrew C. Fry, L. Perry koziris, Jeffrey E. Bauer, James M. Lynch, Tim McConnell, Robert U. Newton, Scott E. Gordon, Richard C. Nelson and Howard G. Knuttgen
Teddy W. Worrell, Laurie D. Booher and Karla M. Hench
The purpose of this study was to compare the injured versus noninjured lower extremity on three single-leg hop tests following inversion ankle sprain. Twenty-two subjects with a history of unilateral inversion ankle sprain participated in this study. Subjects performed the three single-leg hop tests (hop for distance, hop for time, and agility hop). An independent t test was used to compare extremities. No significant differences existed on any hop test for the 22 subjects. In 8 of the 22 subjects who reported pain with activities of daily living and/or sports activities, an independent t test revealed no significant difference on hop test performance between extremities. We conclude that these three single-leg hop tests lack sensitivity (validity) in detecting lower extremity performance deficits as reported by the subjects following inversion ankle sprain.
Richard C. Nelson, Ted S. Gross and Glenn M. Street
The purpose of this report was to provide a model analysis of biomechanical films taken during the women's gymnastic vaulting events of the 1984 Los Angeles Olympic Games. Although a majority of the optional vaults were filmed, only the 16 vaults performed by the competitors in the individual championships were examined. The analysis included calculations of temporal, spatial, and velocity parameters as the gymnast's center of mass moved through four phases of the vault. The phases were identified as Reuther board contact, prehorse flight, horse contact, and posthorse flight. A representative profile of a female gymnast competing in the Games was compiled based on these parameters. This profile indicated that the gymnasts were much smaller than the average population, efficient in the use of the Reuther board and the horse to reach and maintain CM velocities necessary to complete the vault, and agile enough to perform complex airborne rotations during an average posthorse flight duration of .80s.
Jeffrey Paszkewicz, Tristen Webb, Brian Waters, Cailee Welch McCarty and Bonnie Van Lunen
There is a high incidence of anterior cruciate ligament (ACL) injury in adolescents participating in pivoting sports such as soccer, basketball, and handball. Most ACL injuries in athletes are noncontact injuries, with a mechanism of sudden deceleration, change in direction, or landing from a jump. These mechanisms coupled with an increase in contraction of the quadriceps have been shown as risk factors for ACL injuries. Injuries to the ACL may require surgery, a long rehabilitation, and the potential for reinjury. Studies have shown reductions in lower extremity injury rates using training protocols that focus on landing mechanics, balance training, strength training, and/or agility training. There has been some thought that starting preventive training programs with adolescent athletes may be the most effective approach to reducing adolescent ACL injuries.
Focused Clinical Question:
Can lower extremity injury-prevention programs effectively reduce ACL injury rates in adolescent athletes?
Laurie D. Booher, Karla M. Hench, Teddy W. Worrell and Jill Stikeleather
Traditionally, lower extremity strength assessment has been performed in an open kinetic chain. Several authors, however, recommend closed kinetic chain assessment of lower extremity performance. Reliability of closed kinetic chain tests is not available. Therefore, the purpose of this study was to determine the reliability of the following single-leg hop tests: hop for distance, 6-m hop for time, and 30-m agility hop. Eighteen subjects (4 males and 14 females) participated in this study. An ANOVA repeated measures analysis revealed significant differences between the test trials within and between sessions for all dependent variables. However, when the mean of two test trials was analyzed, the three single-leg hop tests values were stable, that is, intraclass correlation coefficient (ICC 2,1) ranged from 0.77 to 0.99. Results demonstrate that these three single-leg hop tests were reliable as used in this study. Future research is needed to determine the sensitivity of these tests in the assessment of lower extremity performance following injury and following rehabilitation procedures.
Jeffrey R. Doeringer, Megan Colas, Corey Peacock and Dustin R. Gatens
cold-water immersion affected an athlete’s postexercise recovery on muscle performance or pain perception. More specifically, looking at muscle performance included flexibility, power, speed, and agility, similar to what is required for completing a sport task. We hypothesized that cold-water immersion
Zakariya Nawasreh, David Logerstedt, Adam Marmon and Lynn Snyder-Mackler
(<7 mo) between the ages 14 and 55 years were enrolled into this study; 9 of them completed 10 sessions of mechanical perturbation training (mechanical group) using the Reactive Agility System (Simbex LLC, Lebanon, NH). Another 9 patients were matched for age and sex using data from patients who
Haley Bookbinder, Lindsay V. Slater, Austin Simpson, Jay Hertel and Joseph M. Hart
with a heart rate (HR) monitor below the pectoralis muscles before completing a 30-minute exercise protocol consisting of 5 rounds of 5 minutes of treadmill exercise and 1 minute of agility. These rounds of treadmill and agility exercise were modeled from a commonly used modified Balke exercise
Yi-Ju Tsai, Chieh-Chie Chia, Pei-Yun Lee, Li-Chuan Lin and Yi-Liang Kuo
included (1) trunk and lower-extremity kinematics during box landing and spike jump landing; (2) volleyball-related sports performance including 10-m shuttle run, agility-T, and vertical jump; and (3) isokinetic strength of the hip and knee muscles. Kinematics were measured using the 6-camera Vicon motion
at what measurement point? a. baseline b. 24-hr period c. 36-hour period d. 48-hr period 16. In this study, the control group participants performed worse on what muscle performance measurement? a. agility b. flexibility c. power d. speed 17. The findings of this study would not support athletes