The Effect of Shoulder Plyometric Training on Amortization Time and Upper-Extremity Kinematics

2016 ◽  
Vol 25 (4) ◽  
pp. 315-323 ◽  
Author(s):  
Kathleen A. Swanik ◽  
Stephen J. Thomas ◽  
Aaron H. Struminger ◽  
Kellie C. Huxel Bliven ◽  
John D. Kelly ◽  
...  
Keyword(s):  
Strength Training ◽  
Upper Extremity ◽  
Internal Rotation ◽  
Outcome Measures ◽  
Injury Risk ◽  
External Rotation ◽  
Tracking System ◽  
Training Group ◽  
Plyometric Training ◽  
Before And After

Context:Plyometric training is credited with providing benefits in performance and dynamic restraint. However, limited prospective data exist quantifying kinematic adaptations such as amortization time, glenohumeral rotation, and scapulothoracic position, which may underlie the efficacy of plyometric training for upper-extremity rehabilitation or performance enhancement.Objective:To measure upper-extremity kinematics and plyometric phase times before and after an 8-wk upper-extremity strength- and plyometric-training program.Design:Randomized pretest–posttest design.Setting:Research laboratory.Participants:40 recreationally active men (plyometric group, age 20.43 ± 1.40 y, height 180.00 ± 8.80 cm, weight 73.07 ± 7.21 kg; strength group, age 21.95 ± 3.40 y, height 173.98 ± 11.91 cm, weight 74.79 ± 13.55 kg).Intervention:Participants were randomly assigned to either a strength-training group or a strength- and plyometric-training group. Each participant performed the assigned training for 8 wk.Main Outcome Measures:Dynamic and static glenohumeral and scapular-rotation measurements were taken before and after the training programs. Dynamic measurement of scapular rotation and time spent in each plyometric phase (concentric, eccentric, and amortization) during a ball-toss exercise were recorded while the subjects were fitted with an electromagnetic tracking system. Static measures included scapular upward rotation at 3 different glenohumeral-abduction angles, glenohumeral internal rotation, and glenohumeral external rotation.Results:Posttesting showed that both groups significantly decreased the time spent in the amortization, concentric, and eccentric phases of a ball-toss exercise (P < .01). Both groups also exhibited significantly decreased static external rotation and increased dynamic scapular upward rotation after the training period (P < .01). The only difference between the training protocols was that the plyometric-training group exhibited an increase in internal rotation that was not present in the strength-training group (P < .01).Conclusion:These findings support the use of both upper-extremity plyometrics and strength training for reducing commonly identified upper-extremity-injury risk factors and improving upper-extremity performance.

scholarly journals Comparison of Upper Extremity Physical Characteristics Between Adolescent Competitive Swimmers and Nonoverhead Athletes

2016 ◽  
Vol 51 (1) ◽  
pp. 65-69 ◽  
Author(s):  
Elizabeth E. Hibberd ◽  
Kevin Laudner ◽  
David J. Berkoff ◽  
Kristen L. Kucera ◽  
Bing Yu ◽  
...  
Keyword(s):  
Upper Extremity ◽  
Internal Rotation ◽  
Technology Use ◽  
Injury Risk ◽  
External Rotation ◽  
Sport Activity ◽  
Physical Characteristics ◽  
Subacromial Space ◽  
Competitive Swimmers ◽  
Space Distance

ContextAlterations to upper extremity physical characteristics of competitive swimmers (posture, range of motion [ROM], and subacromial-space distance) are commonly attributed to cumulative training load during a swimmer's competitive career. However, this accepted clinical belief has not been established in the literature. It is important to understand whether alterations in posture and associated physical characteristics occur as a result of sport training or factors other than swimming participation to better understand injury risk and possible interventions.ObjectiveTo compare posture, subacromial-space distance, and glenohumeral external-rotation, internal-rotation, and horizontal-adduction ROM between adolescent competitive swimmers and nonoverhead athletes.DesignCross-sectional study.SettingLocal swimming pools and high school athletic training rooms.Patients or Other ParticipantsForty-four competitive adolescent swimmers and 31 nonoverhead athletes who were not currently experiencing any elbow, shoulder, neck, or back pain that limited their sport activity.Intervention(s)Posture, subacromial-space distance, and glenohumeral ROM were measured using photography, diagnostic ultrasound, and a digital inclinometer, respectively.Main Outcome Measure(s)Forward shoulder posture, forward head posture, normalized subacromial-space distance, internal-rotation ROM, and external-rotation ROM.ResultsNo clinically significant differences existed between swimmers and nonoverhead athletes for posture, normalized subacromial-space distance, or external- or internal-rotation ROM. Swimmers presented with less horizontal-adduction ROM than nonoverhead athletes.ConclusionsFactors other than swimming participation, such as school and technology use, play important roles in the adaptation of physical characteristics in adolescents. Adolescents, regardless of swimming participation, presented with postural deviations. It is important to consider factors other than swimming participation that contribute to alterations in physical characteristics to understand injury risk and injury-prevention strategies in competitive adolescent swimmers.

scholarly journals Delayed Rehabilitation Protocol after Rotator Cuff Repair

Osteology ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 29-38
Author(s):  
Alessandra Berton ◽  
Sergio De Salvatore ◽  
Vincenzo Candela ◽  
Gabriele Cortina ◽  
Daniela Lo Presti ◽  
...  
Keyword(s):  
Rotator Cuff ◽  
Muscle Strength ◽  
Internal Rotation ◽  
Outcome Measures ◽  
Rotator Cuff Repair ◽  
External Rotation ◽  
Shoulder Function ◽  
Rehabilitation Protocol ◽  
Patient Reported ◽  
Cuff Repair

Rotator cuff tears are a frequent cause of shoulder pain that often require arthroscopic repair. After surgery an intense and well-studied rehabilitation protocol is needed to obtain the complete recovery of shoulder function. Fifty patients, who sustained arthroscopic rotator cuff repair for symptomatic, atraumatic and full-thickness supraspinatus tendon tear, were involved. According to our rehabilitation protocol, during the first four postoperative weeks, the arm was supported with an abduction sling pillow, and pendulum exercises, table slide and active elbow extension and flexion were conceded. Outcome measures (Oxford shoulder score (OSS), simple shoulder test (SST), patient-reported satisfaction), shoulder function (range of motion (ROM) and muscle strength), and MRI examination were evaluated. The mean OSS score and SST score increased from 16 to 30.2 and from 5.3 to 11.4, respectively. Patient-reported satisfaction was 96%. At 12 months, patients improved ROM and muscle strength. Postoperative passive anterior elevation was 176; external rotation averaged 47; internal rotation was 90. Postoperative muscle strength during anterior elevation was 8.3 ± 2.2 kg, internal rotation 6.8 ± 3 kg, external rotation 5.5 ± 2.3 kg. Five out of seven patients with recurrent tears evaluated their results as satisfactory. They reported improvements in terms of OSS and SST mean scores despite recurrent tears; therefore, they did not undergo revision surgery. The delayed postoperative physical therapy protocol was associated with improvements in the outcome measures and shoulder function compared to the preoperatory state and rotator cuff healing demonstrated by MRI.

scholarly journals The Relationship Between Shoulder Range of Motion and Arm Stress in College Pitchers: A MOTUS Baseball Study

2020 ◽  
Vol 8 (7_suppl6) ◽  
pp. 2325967120S0040
Author(s):  
Caleb Gulledge ◽  
Toufic Jildeh ◽  
Joseph Tramer ◽  
Fabien Meta ◽  
Kevin Taylor ◽  
...  
Keyword(s):  
Range Of Motion ◽  
Upper Extremity ◽  
Internal Rotation ◽  
External Rotation ◽  
Outcome Measurement ◽  
Overhead Athletes ◽  
Shoulder Range Of Motion ◽  
Patient Reported ◽  
The Relationship ◽  
Shoulder Range

Objectives: Overuse injuries in overhead athletes are becoming more prevalent, with an unclear relationship between shoulder biomechanics and medial elbow symptoms and injury. The purpose of this study was to investigate the relationship of shoulder range of motion to torque across the medial elbow in college pitchers using a validated MOTUS sensor baseball sleeve. Methods: Pitchers were recruited from three local university baseball teams. Exclusion criteria included injury or restricted activity due to pain. They were evaluated in the preseason, within two weeks before their first game of the season. Pitchers completed workload questionnaires and patient reported outcome measurement information system (PROMIS) pain interference (PI), physical function (PF), and upper extremity (UE) surveys. Shoulder range of motion and upper extremity lengths were measured bilaterally. After adequate warm-up, pitchers were fitted with a MOTUS sensor baseball sleeve (Motus Global, Massapequa, NY) and instructed to throw 5 fastballs in a standardized manner off the mound at game-speed effort. The sensor placed at the medial elbow reported elbow torque, arm speed, arm slot, and shoulder rotation for each pitch, while a radar gun measured peak ball velocity. The primary outcome was to evaluate the relationship between shoulder range of motion and increased stress across the medial elbow. Additional outcomes evaluated pitcher characteristics, demographics, and outcome scores. Outcomes were assessed via a multivariable model, which controlled for possible covariates. Results: Twenty-eight pitchers were included in the preseason analysis with an average (SD) age of 20.1 (1.3) years and playing experience of 15.3 (1.8) years, 2.5 (1.2) of those years at collegiate level. The dominant shoulder demonstrated decreased internal rotation (54.5+/-10.6 vs 65.8+/-9.1) and increased external rotation (ER, 94.1+/-10.4 vs 88.4+/-9.2) relative to the non-dominant side (p < 0.001), while total rotational range of motion (TRROM) was significantly decreased in the dominant arm (148.6+/-12.4 vs 154.1+/-10.6, p < 0.001). The average glenohumeral internal rotation deficiency (GIRD) was 11.3 (9.87) and average external rotation gain (ERG) was 5.71 (8.8). External rotation was found to be a predictor of arm stress, with an increase in 0.35 Nm of elbow torque for every degree increase in ER (beta = 0.35+/-0.06, p = 0.003); there was moderate correlation between ER and arm stress (r = .45, P<.001). Pitchers demonstrated significantly greater arm stress with the following shoulder ROM measurements: GIRD < 20 as compared to greater than 20 degrees (46.6 +/- 0.5 versus 43.5 +/- 1.1, P=.011), ERG greater than 5 as compared to < 5 degrees (47.4 +/- 0.7 versus 45.1 +/- 0.6, P=.014), and loss of total rotational ROM less than 5 as compared to > 5 degrees (46.6 +/- 0.5 versus 43.6 +/- 1.1, P=.013). Multivariate analysis demonstrated significant predictors of PROMIS PF and UE scores were arm stress, ERG, and GIRD (p<0.05), while increased PROMIS PI scores were predicted by increased ERG and GIRD (p<0.05). Conclusion: We found medial elbow stress, arm speed, arm slot, and shoulder rotation as measured by the MOTUS baseball sensor sleeve were influenced by rotational adaptations of the pitching shoulder in collegiate throwing athletes prior to their season. Likewise, arm stress and shoulder rotational adaptations were reflected as predictors of PROMIS PF, UE, and PI scores.

Effect of Posterior Capsule Tightness on Glenohumeral Translation in the Late-Cocking Phase of Pitching

2007 ◽  
Vol 16 (1) ◽  
pp. 41-49 ◽  
Author(s):  
Kim M. Clabbers ◽  
John D. Kelly ◽  
Dov Bader ◽  
Matthew Eager ◽  
Carl Imhauser ◽  
...  
Keyword(s):  
Outcome Measures ◽  
Humeral Head ◽  
Glenohumeral Joint ◽  
External Rotation ◽  
Head Position ◽  
Posterior Capsule ◽  
Nonsignificant Trend ◽  
Before And After ◽  
Fresh Frozen ◽  
Head Translation

Context:Throwing injuries.Objective:To study the effects of posterior capsule tightness on humeral head position in late cocking simulation.Design:Eight fresh frozen shoulders were placed in position of “late cocking,” 90 degrees abduction, and 10 degrees adduction and maximal external rotation. 3D measurements of humeral head relationship to the glenoid were taken with an infrared motion sensor, both before and after suture plication of the posterior capsule. Plications of 20% posterior/inferior capsule and 20% entire posterior capsule were performed, followed by plications of 40% of the posterior/inferior capsule and 40% entire posterior capsule.Setting:Cadaver Lab.Intervention:Posterior capsular placation.Main Outcome Measures:Humeral head position.Results:40%, but not 20%, posterior/inferior and posterior plications demonstrated a trend to increased posterior-superior humeral head translation relative to controls.Conclusion:Surgically created posterior capsular tightness of the glenohumeral joint demonstrated a nonsignificant trend to increased posterior/superior humeral head translation in the late cocking position of throwing.

scholarly journals PLYOMETRIC TRAINING IMPROVES SWIMMING PERFORMANCE IN RECREATIONALLY-TRAINED SWIMMERS

2020 ◽  
Vol 26 (5) ◽  
pp. 436-440
Author(s):  
Rodrigo Cañas-Jamett ◽  
Julio Figueroa-Puig ◽  
Rodrigo Ramirez-Campillo ◽  
Marcelo Tuesta
Keyword(s):  
Swimming Performance ◽  
Training Group ◽  
Control Group ◽  
Jump Height ◽  
Plyometric Training ◽  
Level Of Evidence ◽  
Squat Jump ◽  
Strength Performance ◽  
Swimming Time ◽  
Before And After

ABSTRACT Introduction: Plyometric training significantly improves strength performance, including in aquatic sports. Objective: To compare changes in thigh girth, hamstring flexibility, squat jump height, and 200m swimming trial time induced by plyometric training in recreationally-trained swimmers. Methods: Eighteen recreationally-trained male swimmers (age=18-20 years) were randomly divided into a plyometric training group (PTG) and a control group (CG). All the swimmers completed a six-week speed swimming training plan. In the PTG only, the last ~15 min of each session was replaced with plyometric exercises. The physical characteristics and the thigh girth were measured before and after the six weeks of training. In addition, sit-and-reach flexibility and squat jump tests were conducted, as well as a 200m swimming trial. Results: Two-way ANOVA with post-hoc analysis revealed an increase in sit-and-reach flexibility (PRE: 4.5±5.3 cm; POST: 10.9±5.9 cm, p<0.01) and squat jump height (PRE: 24.9±3.7 cm; POST: 28.3±4.2 cm, p<0.01) and a decrease in 200m-swimming time (PRE: 220±26.5 sec; POST: 204±24.4 sec, p<0.01) for the PTG only. Comparing the absolute changes (post-pre) between the groups by the Student's t-test, the PTG showed a greater increase in distance reached in the sit-and-reach flexibility (PTG: 6.34±0.6 cm vs. CG: 2.4±1.2 cm, p<0.01) and squat jump height (PTG: 3.4±0.7 cm vs. CG: 0.7±0.3 cm, p<0.01) than the CG. In addition, the 200m swimming time decreased significantly more than in the CG (PTG: -15.1±2.4 sec vs. CG: -0.8±2.7 sec, p<0.01). Conclusion: Plyometric training improves jump height, flexibility, and 200m swimming performance in recreationally-trained adult swimmers. Level of Evidence II; Lesser quality RCT.

scholarly journals Changes in Fatigue, Multiplanar Knee Laxity, and Landing Biomechanics During Intermittent Exercise

2015 ◽  
Vol 50 (5) ◽  
pp. 486-497 ◽  
Author(s):  
Sandra J. Shultz ◽  
Randy J. Schmitz ◽  
John R. Cone ◽  
Robert A. Henson ◽  
Melissa M. Montgomery ◽  
...  
Keyword(s):  
Internal Rotation ◽  
Hierarchical Linear Modeling ◽  
Intermittent Exercise ◽  
External Rotation ◽  
Knee Laxity ◽  
Knee Valgus ◽  
Linear Modeling ◽  
Warm Up ◽  
Landing Biomechanics ◽  
Before And After

Context Knee laxity increases during exercise. However, no one, to our knowledge, has examined whether these increases contribute to higher-risk landing biomechanics during prolonged, fatiguing exercise. Objectives To examine associations between changes in fatigue (measured as sprint time [SPTIME]), multiplanar knee laxity (anterior-posterior [APLAX], varus-valgus [VVLAX] knee laxity, and internal-external rotation [IERLAX]) knee laxity and landing biomechanics during prolonged, intermittent exercise. Design Descriptive laboratory study. Setting Laboratory and gymnasium. Patients or Other Participants A total of 30 male (age = 20.3 ± 2.0 years, height = 1.79 ± 0.05 m, mass = 75.2 ± 7.2 kg) and 29 female (age = 20.5 ± 2.3 years, height = 1.67 ± 0.08 m, mass = 61.8 ± 9.0 kg) competitive athletes. Intervention(s) A 90-minute intermittent exercise protocol (IEP) designed to simulate the physiologic and biomechanical demands of a soccer match. Main Outcome Measure(s) We measured SPTIME, APLAX, and landing biomechanics before and after warm-up, every 15 minutes during the IEP, and every 15 minutes for 1 hour after the IEP. We measured VVLAX and IERLAX before and after the warm-up, at 45 and 90 minutes during the IEP, and at 30 minutes after the IEP. We used hierarchical linear modeling to examine associations between exercise-related changes in SPTIME and knee laxity with exercise-related changes in landing biomechanics while controlling for initial (before warm-up) knee laxity. Results We found that SPTIME had a more global effect on landing biomechanics in women than in men, resulting in a more upright landing and a reduction in landing forces and out-of-plane motions about the knee. As APLAX increased with exercise, women increased their knee internal-rotation motion (P = .02), and men increased their hip-flexion motion and energy-absorption (P = .006) and knee-extensor loads (P = .04). As VVLAX and IERLAX increased, women went through greater knee-valgus motion and dorsiflexion and absorbed more energy at the knee (P ≤ .05), whereas men were positioned in greater hip external and knee internal rotation and knee valgus throughout the landing (P = .03). The observed fatigue- and laxity-related changes in landing biomechanics during exercise often depended on initial knee laxity. Conclusions Both exercise-related changes in fatigue and knee laxity were associated with higher-risk landing biomechanics during prolonged exercise. These relationships were more pronounced in participants with greater initial knee laxity.

scholarly journals Short-Term Performance Effects of Three Different Low-Volume Strength-Training Programmes in College Male Soccer Players

2014 ◽  
Vol 40 (1) ◽  
pp. 121-128 ◽  
Author(s):  
João Brito ◽  
Fabrício Vasconcellos ◽  
José Oliveira ◽  
Peter Krustrup ◽  
António Rebelo
Keyword(s):  
Strength Training ◽  
Training Group ◽  
Peak Torque ◽  
Soccer Players ◽  
Control Group ◽  
Plyometric Training ◽  
Short Term ◽  
Performance Effects ◽  
Low Volume ◽  
Training Programmes

Abstract This study aimed to analyse the short-term performance effects of three in-season low-volume strength-training programmes in college male soccer players. Fifty-seven male college soccer players (age: 20.31.6 years) were randomly assigned to a resistance-training group (n=12), plyometric training group (n=12), complex training group (n=12), or a control group (n=21). In the mid-season, players underwent a 9-week strength-training programme, with two 20 min training sessions per week. Short-term effects on strength, sprint, agility, and vertical jump abilities were measured. All training groups increased 1-RM squat (range, 17.2-24.2%), plantar flexion (29.1-39.6%), and knee extension (0.5- 22.2%) strength compared with the control group (p<0.05). The resistance-training group increased concentric peak torque of the knee extensor muscles by 9.9-13.7%, and changes were greater compared with the control group (p<0.05). The complex training group presented major increments (11.7%) in eccentric peak torque of the knee flexor muscles on the non-dominant limb compared with the control group and plyometric training group (p<0.05). All training groups improved 20-m sprint performance by 4.6-6.2% (p<0.001) compared with the control group. No differences were observed in 5-m sprint and agility performances (p>0.05). Overall, the results suggest that in-season low-volume strength training is adequate for developing strength and speed in soccer players.

scholarly journals Can Technique Modification Training Reduce Knee Moments in a Landing Task?

2014 ◽  
Vol 30 (2) ◽  
pp. 231-236 ◽  
Author(s):  
Alasdair R. Dempsey ◽  
Bruce C. Elliott ◽  
Bridget J. Munro ◽  
Julie R. Steele ◽  
David G. Lloyd
Keyword(s):  
Internal Rotation ◽  
Injury Risk ◽  
Cruciate Ligament ◽  
Three Dimensional ◽  
Inverse Dynamic ◽  
Acl Injuries ◽  
Can Technique ◽  
Before And After ◽  
Reaction Forces ◽  
Anterior Cruciate

Anterior cruciate ligament (ACL) injuries are costly. Sidestep technique training reduces knee moments that load the ACL. This study examined whether landing technique training alters knee moments. Nineteen team sport athletes completed the study. Motion analysis and ground reaction forces were recorded before and after 6 weeks of technique modification. An inverse dynamic model was used to calculate three-dimensional knee loading. Pre- and postintervention scores were compared using pairedttests. Maximal knee flexion angle during landing was increased following training. There was no change in valgus or flexion moments, but an increase in peak internal rotation moment. This increase in internal rotation moment may increase the risk of ACL injury. However, the increased angle at which the peak internal rotation moment occurred at follow up may mitigate any increase in injury risk by reducing load transmission.

Comparisons of Land-Based and Aquatic-Based Plyometric Programs during an 8-Week Training Period

2002 ◽  
Vol 11 (4) ◽  
pp. 268-283 ◽  
Author(s):  
Michael G. Miller ◽  
David C. Berry ◽  
Susan Bullard ◽  
Roger Gilders
Keyword(s):  
Outcome Measures ◽  
Muscle Soreness ◽  
Muscle Power ◽  
Plantar Flexion ◽  
Sport Performance ◽  
Analysis Of Covariance ◽  
Training Period ◽  
Plyometric Training ◽  
Performance Variables ◽  
Before And After

Context:Land and aquatic plyometrics have clinical relevance for exercise, sport performance, and rehabilitation, yet study is limited comparing both.Objective:To compare the effects of land-based and aquatic-based plyometric-training programs on performance variables, muscle soreness, and range of motion (ROM).Setting:Aquatic facility and biomechanics laboratory.Subjects:Forty subjects randomly assigned to 3 groups: land (n = 13), water (n = 13), and control (n = 14).Main Outcome Measures:Performance variables, muscle soreness, and ROM were measured before and after an 8-week training period. An analysis of covariance (ANCOVA) and a Bonferroni post hoc test determined significance.Results:ANCOVA revealed significant differences between groups with respect to plantar-flexion ROM (P< .05). Pairedttest determined that the aquatic group significantly increased muscle power pretest to posttest (P< .05).Conclusions:Results indicate that aquatic plyometric training can be an alternative approach to enhancing performance.

Different Kinematics of Knees with Varus and Valgus Deformities

2017 ◽  
Vol 31 (03) ◽  
pp. 264-269 ◽  
Author(s):  
A. Benditz ◽  
F. Koeck ◽  
A. Keshmiri ◽  
J. Grifka ◽  
G. Maderbacher ◽  
...  
Keyword(s):  
Internal Rotation ◽  
External Rotation ◽  
Computer Navigation ◽  
Movement Pattern ◽  
Varus Deformity ◽  
Valgus Deformity ◽  
Significant Difference ◽  
Before And After ◽  
Tibiofemoral Kinematics

AbstractFew data exist of kinematics of knees with varus and valgus deformities combined with osteoarthritis. The purpose of this study was to reveal different (1) tibiofemoral kinematics, (2) medial and lateral gaps, and (3) condylar liftoff of osteoarthritic knees with either varus or valgus deformity before and after total knee arthroplasty (TKA). For this purpose, 40 patients for TKA were included in this study, 23 knees with varus deformity and 17 knees with valgus deformity. All patients underwent computer navigation, and kinematics was assessed before making any cuts or releases and after implantation. Osteoarthritic knees with valgus deformity showed a significant difference in tibia rotation relative to the femur with flexion before and after TKA, whereas knees with varus deformity did not. Knees with a valgus deformity showed femoral external rotation in extension and femoral internal rotation in flexion, whereas knees with a varus deformity revealed femoral internal rotation in extension and femoral external rotation in flexion. In both groups, gaps increased after TKA. Condylar liftoff was not observed in the varus deformity group after TKA. In the valgus deformity group, condylar liftoff was detected after TKA at knee flexion of 50 degrees and more. This study revealed significant differences in tibiofemoral kinematics between osteoarthritic knees with a varus or valgus deformity before and after TKA. Valgus deformities showed a paradoxic movement pattern. These in vivo intraoperative results need to be confirmed using fluoroscopic or radiographic three-dimensional matching before and after TKA.

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