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W D Bandy

Publications and source records attributed to W D Bandy.

8 recordsLinked to original sources

The effect of static stretch and dynamic range of motion training on the flexibility of the hamstring muscles.

To date, limited information exists describing a relatively new stretching technique, dynamic range of motion (DROM). The purpose of this study was to compare the effects of DROM with static stretch on hamstring flexibility. Fifty-eight subjects, ranging in age from 21 to 41 years and with limited hamstring flexibility (defined as 30 degrees loss of knee extension measured with the femur held at 90 degrees of hip flexion), were randomly assigned to one of three groups. One group performed DROM 5 days a week by lying supine with the hip held in 90 degrees of flexion. The subject then actively moved the leg into knee extension (5 seconds), held the leg in end range knee extension for 5 seconds, and then slowly lowered the leg to the initial position (5 seconds). These movements were performed six times per session (30 seconds of total actual stretching time). The second group performed one 30-second static stretch, 5 days per week. The third group served as a control group and did not stretch. Before and after 6 weeks of training, flexibility of the hamstring muscles was determined in all three groups by measuring knee extension range of motion (ROM) with the femur maintained in 90 degrees of hip flexion. Data were analyzed with a 2 x 3 (test x group) two-way analysis of variance (ANOVA) with repeated measures on one variable (test) and appropriate post hoc analyses. The results of the two-way ANOVA revealed a significant interaction. Further statistical post hoc analysis of data to interpret the interaction revealed significant differences between the control group (gain = 0.70 degree) and both stretching groups, as well as a significant difference between the static stretch group (gain = 11.42 degrees) and the DROM group (gain = 4.26 degrees). The results of this study suggest that, although both static stretch and DROM will increase hamstring flexibility, a 30-second static stretch was more effective than the newer technique, DROM, for enhancing flexibility. Given the fact that a 30-second static stretch increased ROM more than two times that of DROM, the use of DROM to increase flexibility of muscle must be questioned.

Adult↗

The effect of time and frequency of static stretching on flexibility of the hamstring muscles.

BACKGROUND AND PURPOSE: Frequency and duration of static stretching have not been extensively examined. Additionally, the effect of multiple stretches per day has not been evaluated. The purpose of this study was to determine the optimal time and frequency of static stretching to increase flexibility of the hamstring muscles, as measured by knee extension range of motion (ROM). SUBJECTS: Ninety-three subjects (61 men, 32 women) ranging in age from 21 to 39 years and who had limited hamstring muscle flexibility were randomly assigned to one of five groups. The four stretching groups stretched 5 days per week for 6 weeks. The fifth group, which served as a control, did not stretch. METHODS: Data were analyzed with a 5 x 2 (group x test) two-way analysis of variance for repeated measures on one variable (test). RESULTS: The change in flexibility appeared to be dependent on the duration and frequency of stretching. Further statistical analysis of the data indicated that the groups that stretched had more ROM than did the control group, but no differences were found among the stretching groups. CONCLUSION AND DISCUSSION: The results of this study suggest that a 30-second duration is an effective amount of time to sustain a hamstring muscle stretch in order to increase ROM. No increase in flexibility occurred when the duration of stretching was increased from 30 to 60 seconds or when the frequency of stretching was increased from one to three times per day.

Adult↗

Predictive validity of an injury score among high school basketball players.

A number of strategies have been investigated in an attempt to identify those individuals most likely to be injured during participation in sports activity. One such strategy identified in the literature involved computing an "injury score" via a logistic regression equation using measures of structural symmetry to predict the likelihood of athletic injury. The purpose of this study was to investigate the predictive value of the injury score among high school basketball players. Following the establishment of reliability of measures, injury scores were calculated for 62 high school basketball players (34 females, 28 males) before the start of the season. Lower extremity injuries sustained while playing basketball were recorded throughout the season. The predictive value of the injury score equation was determined by calculating sensitivity, specificity, and positive and negative predictive values. The sensitivity and specificity were calculated to be 16.7% and 66.1%, respectively. The positive and negative predictive values were calculated to be 5.90% and 88.1%, respectively. These results indicate that the injury prediction score investigated was not a valid means of predicting injury in high school basketball players. Limitations, possible implications of these findings, and ideas for future related research are presented.

Adolescent↗

False aneurysm--a complication following an inversion ankle sprain: a case report.

Sprains of the lateral ligamentous structures of the ankle joint as a result of inversion are common and frequently result in pain. In most cases, the pain is related to soft-tissue injury and the associated hemorrhage and swelling. This case report describes the complication of posttraumatic false aneurysm of the peroneal artery following an inversion ankle sprain in a 22-year-old athlete, a complication which should be added to the differential diagnosis as a rare, but important possibility. Emphasis of the case report is placed on the rehabilitation of the patient following medical intervention.

Adult↗

Relationship of isokinetic peak torque with work and power for ankle plantar flexion and dorsiflexion.

Past research has analyzed the relationship of peak torque with work and power on the muscles surrounding the knee with correlation coefficients being reported, ranging from .67 to .99. No studies to date have examined this relationship for muscles surrounding the ankle joint. The purpose of this study was to analyze the relationship of peak torque with work and power for the plantar flexor and dorsiflexor muscles of the ankle. Isokinetic data were collected from 15 healthy subjects (six males, nine females; mean age = 26.6 years) on an isokinetic dynamometer across two trials at speeds of 30 and 120 degrees/sec. The results of Pearson product moment correlations between peak torque to work and peak torque to power indicated correlation coefficients ranging from .81 to .97 for all speeds of testing and angular velocities. These findings suggest that peak torque is representative of work and power.

Adult↗

The effect of time on static stretch on the flexibility of the hamstring muscles.

BACKGROUND AND PURPOSE: To date, there are no reports comparing duration of static stretch in humans on joint range of motion (ROM) and hamstring muscle flexibility. The purpose of this study was to examine the length of time the hamstring muscles should be placed in a sustained stretched position to maximally increase ROM. SUBJECTS: Fifty-seven subjects (40 men, 17 women), ranging in age from 21 to 37 years and with limited hamstring muscle flexibility (ie, 30 degrees loss of knee extension measured with femur held at 90 degrees of hip flexion), were randomly assigned to one of four groups. Three groups stretched 5 days per week for 15, 30, and 60 seconds, respectively. The fourth group, which served as a control group, did not stretch. METHODS: Before and after 6 weeks of stretching, flexibility of the hamstring muscles was determined by measuring knee extension ROM with the femur maintained in 90 degrees of hip flexion. Data were analyzed with a 4 x 2 analysis of variance (group x test) for repeated measures on one variable. RESULTS: The data analysis revealed a significant group x test interaction, indicating that the change in flexibility was dependent on the duration of stretching. Further post hoc analysis revealed that 30 and 60 seconds of stretching were more effective at increasing flexibility of the hamstring muscles (as determined by increased ROM of knee extension) than stretching for 15 seconds or no stretching. In addition, no significant difference existed between stretching for 30 seconds and for 1 minute, indicating that 30 seconds of stretching the hamstring muscles was as effective as the longer duration of 1 minute. CONCLUSION AND DISCUSSION: The results of this study suggest that a duration of 30 seconds is an effective time of stretching for enhancing the flexibility of the hamstring muscles. Given the information that no increase in flexibility of the hamstring muscles occurred by increasing the duration of stretching from 30 to 60 seconds, the use of the longer duration of stretching for an acute effect must be questioned.

Adult↗

Changes in torque and electromyographic activity of the quadriceps femoris muscles following isometric training.

BACKGROUND AND PURPOSE: The purpose of this study was to examine the effect of isometric training of the quadriceps femoris muscles, at different joint angles, on torque production and electromyographic (EMG) activity. SUBJECTS: One hundred seven women were randomly assigned to one of four groups. Three groups trained with isometric contractions three times per week at a knee flexion angle of 30, 60, or 90 degrees. The fourth group, which served as a control, did not exercise. METHODS: Isometric torque was measured using a dynamometer, and EMG activity was measured using a multichannel EMG system. Measurements were obtained during maximal isometric contraction of the quadriceps femoris muscles at 15-degree increments from 15 to 105 degrees of knee flexion. Measurements were taken before and after 8 weeks of training. RESULTS: Following isometric exercise, increased torque and EMG activity occurred not only at the angle at which subjects exercised, but also at angles in the range of motion at which exercise did occur. Further analyses indicated that exercising in the lengthened position for the quadriceps femoris muscles (90 degrees of knee flexion) produced increased torque across all angles measured and appeared to be the more effective position for transferring strength and EMG activity to adjacent angles following isometric training as compared with the shorter positions of the muscle (30 degrees and 60 degrees of knee flexion). CONCLUSION AND DISCUSSION: These findings suggest that an efficient method for increasing isometric knee extension torque and EMG activity throughout the entire range of motion is to exercise with the quadriceps femoris muscles in the lengthened position.

Adult↗

Intramachine and intermachine reliability for selected dynamic muscle performance tests.

The Cybex 6000 isokinetic dynamometer is a new isokinetic device for which no published reports of reliability have been presented in the literature. In addition, the manufacturer not only claims that the new Cybex 6000 is reliable but that torque data obtained from the Cybex 6000 are consistent with data obtained from past Cybex systems, such as the Cybex II. The purpose of this study was to investigate the intramachine reliability of the Cybex 6000 to itself and the intermachine reliability of the Cybex 6000 and the Cybex II. Data on peak torque, work, and power were collected using the Cybex 6000, and data on peak torque were obtained using the Cybex II for knee flexion and extension in 20 volunteers (10 males, 10 females). Subjects were tested three times, twice on the Cybex 6000 and once on the Cybex II, approximately 1 week apart across a 3-week period of time at angular velocities of 60, 180, and 300 degrees/sec. Data were analyzed using intraclass correlations. Results indicated that the majority of test-retest correlation coefficients for all parameters for intramachine reliability of the Cybex 6000 were above .90. Comparing peak torque obtained with the Cybex 6000 to that obtained with the Cybex II (intermachine reliability), correlation coefficients ranged from .72 to .89. In conclusion, information obtained on the Cybex 6000 appears to be quite reliable in a test-retest situation using the same equipment and moderately reliable when compared to the Cybex II. Clinical implications for these results are discussed.

Adult↗