C. Buz Swanik
C. Buz Swanik and Kathleen A. Swanik
Julie A. Siegmund, Kellie C. Huxel and C. Buz Swanik
Determining whether there are compensations in those with jumper’s knee (JK) might further our understanding of the condition.
Comparing lower extremity kinematics and jump performance of basketball athletes with JK with those of healthy controls (C).
Repeated-measures control-match design.
24 male basketball players (12 JK, 12 C) matched by height, weight, position, experience, and frequency of play.
Standing countermovement and running layup jumps.
Main Outcome Measures:
Maximum vertical-jump height, footfall landing, and lower extremity sagittal-plane kinematics.
There were no significant group differences (P > .05) in vertical-jump height (JK = 64.3 ± 8.6 cm, C = 63.0 ± 9.8 cm) or layup height (JK = 71.3 ± 11.6 cm, C = 73.3 ± 11.0 cm). JK subjects landed flat footed (50%) more than controls (8%). JK subjects showed significantly more hip flexion (JK = 105° ± 24.8°, C = 89.8° ± 14.1°; P = .039) with decreased hip acceleration during the countermovement (JK = −3039 ± 1392°/s2, C = −4229 ± 1765°/s2; P = .040). When landing from the countermovement jump, JK subjects had significantly less knee acceleration (JK = −4960 ± 1512°/s2, C = −6736 ± 2009°/s2; P = 023) and in the layup showed significantly less ankle dorsiflexion (JK = 106.5° ± 9.0°, C = 112.5° ± 7.7°; P = .048) and hip acceleration (JK = − 2841 ± 1094°/s2, C = −3912 ± 1575°/s2; P = .033).
Compensatory strategies observed in JK subjects might help maintain performance, because their jump height was similar to that of healthy controls.
Kathleen J. Ashmen, C. Buz Swanik and Scott M. Lephart
The purpose of this study was to identify strength and flexibility deficits in subjects with chronic low-back pain (CLBP). Subjects were 16 female Division I athletes: 8 athletes who had experienced CLBP for at least 6 months prior to testing and a control group of 8 matched subjects. Athletes with neurological symptoms, previous back operations, and leg length discrepancies and those who were diagnosed with scoliosis, spondylolisthesis, or spondylolysis were excluded from this study. Variables assessed included abdominal strength, erector spinae endurance, hip flexion and extension endurance, torso lateral flexibility, and low-back flexibility. Strength and endurance were calculated as a function of time in seconds. Goniometric measurements were used to determine flexibility. Significant mean differences were found by using dependent t tests for abdominal strength, erector Spinae endurance, hip extension, and right lateral flexion of the torso. The results validate the necessity for pelvic stabilization and indicate that strength and flexibility deficits vary among populations.
Hidetomo Suzuki, Kathleen A. Swanik, Kellie C. Huxel, John D. Kelly IV and C. Buz Swanik
To determine the effect of scapular fatigue on shoulder and elbow kinematics and accuracy.
30 healthy men.
Subjects performed seated overhead throws into a target before and after a standardized scapular-muscle-fatigue protocol.
Main Outcome Measurements:
Shoulder and elbow kinematic data were analyzed during throwing. Scapular upward rotation was measured (0°, 45°, and 90° humeral elevation in scaption) with an inclinometer. Throwing accuracy was measured as mean error distance from the target (cm).
After fatigue, there was a significant increase in total elbow motion (12 % more in cocking phase, P < .05) and elbow velocity in the follow-through phase (average and maximum into flexion, P < .05). Throwing accuracy decreased 26% after fatigue (P < .05).
Scapular-muscle fatigue results in compensatory motions at the elbow that might affect performance and contribute to elbow pathologies.
Stephen J. Thomas, Kathleen A. Swanik, Charles “Buz” Swanik, Kellie C. Huxel and John D. Kelly IV
Pathologies such as anterior instability and impingement are common in baseball and have been linked to decreases in internal rotation (IR) and concurrent increases in external rotation (ER). In addition, alterations to scapular position have been identified in this population, but the chronology of these adaptations is uncertain.
To determine whether there is a change in range of motion and scapular position after a single baseball season.
19 high school baseball players (age 16.6 ± 0.8 y, mass 78.6 ± 12.0 kg, height 180.3 ± 6.2 cm).
Subjects were measured for all dependent variables at preseason and postseason.
Main Outcome Measures:
Participants were measured for glenohumeral (GH) IR and ER with the scapula stabilized. Total GH range of motion was calculated as the sum of IR and ER. Scapular upward rotation was measured at 0°, 60°, 90°, and 120° of GH abduction in the scapular plane, and scapular protraction, at 0°, hands on hips, and 90° of GH abduction.
Overall, the dominant arm had significantly less GH IR (11.4°, P = .005) and significantly more ER (4.7°, P = .001) than the nondominant arm. Total motion in the dominant arm was significantly less than in the nondominant arm (6.7°, P = .001). Scapular upward rotation in the dominant arm significantly increased at 0° (2.4°, P = .002) and significantly decreased at 90° (3.2°, P = .001) and 120° (3.2°, P < .001) of abduction from preseason to postseason. Scapular protraction in the nondominant arm significantly decreased at 45° (0.32 cm, P = .017) and 90° (0.33 cm, P = .006) from preseason to postseason.
These data suggest that scapular adaptations may be acquired over a relatively short period (12 wk) in a competitive baseball season. Competitive high school baseball players also presented with significant GH motion differences between their dominant and nondominant arms. Total motion was also significantly less in the dominant arm than in the nondominant arm.
Kathleen A. Swanik, C. Buz Swanik, Scott M. Lephart and Kellie Huxel
To determine whether functional training reduces the incidence of shoulder pain and increases strength in intercollegiate swimmers.
Laboratory and weight room.
26 intercollegiate swimmers (13 men, 13 women).
6-wk functional training program.
Main Outcome Measures:
Incidence of shoulder pain was recorded throughout the study. Isokinetic shoulder strength was assessed before and after training.
A t test showed significant differences (P < .05) for the incidence of shoulder pain between the experimental (mean episodes = 1.8 ± 2.1) and control (mean episodes = 4.6 ± 4.7) groups. ANOVA with repeated measures revealed no significant strength differences between groups but exhibited significant within-group increases.
Incorporating functional exercises might reduce incidence of shoulder pain in swimmers. The results also validate the need to modify preventive programs as the demands of the sport change throughout the season.