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William E Garrett - One of the best experts on this subject based on the ideXlab platform.
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Hamstring Muscle tendon unit lengthening and activation in instep and cut off kicking
Journal of Biomechanics, 2020Co-Authors: Liwen Zhang, William E Garrett, Hui LiuAbstract:Abstract Hamstring Muscle strain injury is one of the most common injuries in sports involving sprinting and kicking. Studies examining Hamstring kinematics and activations are rich for sprinting but lacking for kicking. The purpose of this study was to examine kinematics and activations of Hamstring Muscles in instep and cut-off kicking tasks frequently performed in soccer. Videographic and electromyographic (EMG) data were collected for 11 male soccer-majored college students performing the two kicking tasks. Peak Hamstring Muscle-tendon unit lengths, elongation velocities, and maximum linear envelop EMG data were identified and compared among Hamstring Muscles and between kicking tasks. Hamstring Muscles exhibited activated elongations before and after the contact of the kicking foot with the ball. The Muscle-tendon unit lengths peaked in the follow-through phase. The peak elongation velocity of the semimembranosus was significantly greater than that of the semitendinosus and biceps femoris (p = 0.001). The maximum linear envelop EMG of the biceps femoris was significantly greater than that of the semimembranosus (p = 0.026). The potential for Hamstring injury exists in the follow-through phase of each kicking task. The increased Hamstring Muscle-tendon unit elongation velocities in kicking tasks may explain the more severe Hamstring injuries in kicking compared to sprinting.
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the effect of Hamstring flexibility on peak Hamstring Muscle strain in sprinting
Journal of Sport and Health Science, 2017Co-Authors: Xianglin Wan, William E Garrett, Hui LiuAbstract:Abstract Background The effect of Hamstring flexibility on the peak Hamstring Muscle strains in sprinting, until now, remained unknown, which limited our understanding of risk factors of Hamstring Muscle strain injury (Hamstring injury). As a continuation of our previous study, this study was aimed to examine the relationship between Hamstring flexibility and peak Hamstring Muscle strains in sprinting. Methods Ten male and 10 female college students participated in this study. Hamstring flexibility, isokinetic strength data, three-dimensional (3D) kinematic data in a Hamstring isokinetic test, and kinematic data in a sprinting test were collected for each participant. The optimal Hamstring Muscle lengths and peak Hamstring Muscle strains in sprinting were determined for each participant. Results The Muscle strain of each of the 3 biarticulated Hamstring Muscles reached a peak during the late swing phase. Peak Hamstring Muscle strains were negatively correlated to Hamstring flexibility (0.1179 ≤ R 2 ≤ 0.4519, p = 0.001) but not to hip and knee joint positions at the time of peak Hamstring Muscle strains. Peak Hamstring Muscle strains were not different for different genders. Peak Muscle strains of biceps long head (0.071 ± 0.059) and semitendinosus (0.070 ± 0.055) were significantly greater than that of semimembranosus (0.064 ± 0.054). Conclusion A potential for Hamstring injury exists during the late swing phase of sprinting. Peak Hamstring Muscle strains in sprinting are negatively correlated to Hamstring flexibility across individuals. The magnitude of peak Muscle strains is different among Hamstring Muscles in sprinting, which may explain the different injury rate among Hamstring Muscles.
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relationships among Hamstring Muscle optimal length and Hamstring flexibility and strength
Journal of Sport and Health Science, 2017Co-Authors: Xianglin Wan, William E Garrett, Hui LiuAbstract:Background Hamstring Muscle strain injury (Hamstring injury) due to excessive Muscle strain is one of the most common injuries in sports. The relationships among Hamstring Muscle optimal lengths and Hamstring flexibility and strength were unknown, which limited our understanding of risk factors for Hamstring injury. This study was aimed at examining the relationships among Hamstring Muscle optimal length and flexibility and strength.
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Hamstring Muscle kinematics and activation during overground sprinting
Journal of Biomechanics, 2008Co-Authors: Robin M Queen, Alicia N Abbey, Yu Liu, Claude T Moorman, William E GarrettAbstract:Abstract Hamstring Muscle strain injury is one of the most commonly seen injuries in sports such as track and field, soccer, football, and rugby. The purpose of this study was to advance our understanding of the mechanisms of Hamstring Muscle strain injuries during over ground sprinting by investigating Hamstring Muscle–tendon kinematics and Muscle activation. Three-dimensional videographic and electromyographic (EMG) data were collected for 20 male runners, soccer or lacrosse players performing overground sprinting at their maximum effort. Hamstring Muscle–tendon lengths, elongation velocities, and linear envelop EMG data were analyzed for a running gait cycle of the dominant leg. Hamstring Muscles exhibited eccentric contractions during the late stance phase as well as during the late swing phase of overground sprinting. The peak eccentric contraction speeds of the Hamstring Muscles were significantly greater during the late swing phase than during the late stance phase ( p =0.001) while the Hamstring Muscle–tendon lengths at the peak eccentric contraction speeds were significantly greater during the late stance phase than during the late swing phase ( p =0.001). No significant differences existed in the maximum Hamstring Muscle–tendon lengths between the two eccentric contractions. The potential for Hamstring Muscle strain injury exists during the late stance phase as well as during the late swing phases of overground sprinting.
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electromyographic and kinematic analysis of cutting maneuvers implications for anterior cruciate ligament injury
American Journal of Sports Medicine, 2000Co-Authors: Scott M Colby, Anthony C Francisco, Donald T Kirkendall, Michael Finch, William E GarrettAbstract:The objective of this study was to qualitatively characterize quadriceps and Hamstring Muscle activation as well as to determine knee flexion angle during the eccentric motion of sidestep cutting, cross-cutting, stopping, and landing. Fifteen healthy collegiate and recreational athletes performed the four movements while knee angle and electromyographic activity (surface electrodes) of the vastus lateralis, vastus medialis obliquus, rectus femoris, biceps femoris, and medial Hamstring (semimembranosus/semitendinosus) Muscles were recorded. The results indicated that there is high-level quadriceps Muscle activation beginning just before foot strike and peaking in mid-eccentric motion. In these maneuvers, the level of quadriceps Muscle activation exceeded that seen in a maximum isometric contraction. Hamstring Muscle activation was submaximal at and after foot strike. The maximum quadriceps Muscle activation for all maneuvers was 161% maximum voluntary contraction, while minimum Hamstring Muscle activity was 14%. Foot strike occurred at an average of 22 degrees of knee flexion for all maneuvers. This low level of Hamstring Muscle activity and low angle of knee flexion at foot strike and during eccentric contraction, coupled with forces generated by the quadriceps Muscles at the knee, could produce significant anterior displacement of the tibia, which may play a role in anterior cruciate ligament injury.
Peter G Barnes - One of the best experts on this subject based on the ideXlab platform.
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assessment of physical examination and magnetic resonance imaging findings of Hamstring injury as predictors for recurrent injury
Journal of Orthopaedic & Sports Physical Therapy, 2006Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G Barnes, G T Fon, Adrian EstermanAbstract:Study Design Prospective cohort study. Objective To examine clinical and magnetic resonance imaging (MRI) features of Hamstring Muscle injury to determine if any are predictive for recurrent injury. Background Hamstring Muscle strain injury and subsequent recurrent injury are common. Little information exists on factors that may increase the risk for recurrent injury. Methods and Measures The subjects were athletes from 3 professional Australian Rules football teams (n = 162). Anthropometric measurements, clinical signs, convalescent interval, and MRI assessment and measurement were undertaken and recorded in athletes with Hamstring Muscle strain injury. Athletes were followed for the presence, or absence, of recurrent injury to the same-side posterior thigh over the same and subsequent playing seasons. Results Thirty athletes met criteria for Hamstring injury. Twelve (40%) of 30 athletes had recurrent injury within the same season, with an additional 7 athletes having recurrent injury in the subsequent s...
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the effect of sports specific training on reducing the incidence of Hamstring injuries in professional australian rules football players
British Journal of Sports Medicine, 2005Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G BarnesAbstract:Objectives: To assess in a single team of Australian Rules football players the effect of a specific intervention program on the incidence and consequence of Hamstring Muscle strain injuries. Method: A prospective study was performed with a single team being followed for four playing seasons for Hamstring injury. Magnetic resonance imaging was used to confirm the diagnosis of Hamstring Muscle injury. After two playing seasons an intervention program was implemented with the number of athletes with Hamstring injury, competition days missed, and incidence of Hamstring match injuries per 1000 h of playing time being compared pre- and post-intervention. The intervention program involved stretching whilst fatigued, sport specific training drills, and an emphasis on increasing the amount of high intensity anaerobic interval training. Results: In the seasons prior to the intervention, nine and 11 athletes sustained Hamstring injury compared to two and four following intervention. Competition days missed reduced from 31 and 38 to 5 and 16 following intervention and match incidence decreased from 4.7 to 1.3 per 1000 h of playing time. A beneficial effect was demonstrated with a smaller number of players having Hamstring injuries (p = 0.05), a lower number of competition games missed being recorded (p Conclusions: Increasing the amount of anaerobic interval training, stretching whilst the Muscle is fatigued, and implementing sport specific training drills resulted in a significant reduction in the number and consequences of Hamstring Muscle strain injuries.
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diagnostic and prognostic value of clinical findings in 83 athletes with posterior thigh injury comparison of clinical findings with magnetic resonance imaging documentation of Hamstring Muscle strain
American Journal of Sports Medicine, 2003Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G BarnesAbstract:BackgroundLittle is known about the clinical features of posterior thigh injuries and their contribution to accurate diagnosis and prognostic assessment of Hamstring Muscle strain injury.HypothesesThe clinical features of posterior thigh injury can be used to diagnose Hamstring Muscle strain and to predict duration of absence from competition.Study DesignProspective clinical study.MethodsFor two playing seasons, the clinical features of posterior thigh injury, timing of injury, and playing days lost were recorded for Australian Rules football players. Magnetic resonance imaging was used to confirm Hamstring Muscle injury.ResultsPosterior thigh injuries associated with pain and tenderness were recorded for 83 players, with magnetic resonance imaging confirming Hamstring injury in 68 (82%). Most of the Hamstring injuries were sudden onset (62; 91%) and occurred after a significant warm-up period (57; 84%). Of the patients whose injuries were sudden onset and occurred after the warm-up period (N = 59), 57 (9...
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clinical risk factors for Hamstring Muscle strain injury a prospective study with correlation of injury by magnetic resonance imaging
British Journal of Sports Medicine, 2001Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G Barnes, G T Fon, A J SprigginsAbstract:Objective—To prospectively establish risk factors for Hamstring Muscle strain injury using magnetic resonance imaging (MRI) to define the diagnosis of posterior thigh injury. Method—In a prospective cohort study using two elite Australian Rules football clubs, the anthropometric characteristics and past clinical history of 114 athletes were recorded. Players were followed throughout the subsequent season, with posterior thigh injuries being documented. Hamstring intramuscular hyperintensity on T2 weighted MRI was required to meet our criteria for a definite Hamstring injury. Statistical associations were sought between anthropometric and previous clinical characteristics and Hamstring Muscle injury. Results—MRI in 32 players showed either Hamstring injury (n = 26) or normal scans (n = 6). An association existed between a Hamstring injury and each of the following: increasing age, being aboriginal, past history of an injury to the posterior thigh or knee or osteitis pubis (all p<0.05). These factors were still significant when players with a past history of posterior thigh injury (n = 26) were excluded. Previous back injury was associated with a posterior thigh injury that looked normal on MRI scan, but not with an MRI detected Hamstring injury. Conclusions—Hamstring injuries are common in Australian football, and previous posterior thigh injury is a significant risk factor. Other factors, such as increasing age, being of aboriginal descent, or having a past history of knee injury or osteitis pubis, increase the risk of Hamstring strain independently of previous posterior thigh injury. However, as the numbers in this study are small, further research is needed before definitive statements can be made. (Br J Sports Med 2001;35:435‐440)
Geoffrey M Verrall - One of the best experts on this subject based on the ideXlab platform.
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assessment of player performance following return to sport after Hamstring Muscle strain injury
Journal of Science and Medicine in Sport, 2006Co-Authors: Geoffrey M Verrall, Y Kalairajah, John P Slavotinek, A J SprigginsAbstract:Summary Objective: To determine if there is any decrease in playing performance of athletes following return to sport after recovery from Hamstring Muscle strain injury. Design: Prospective cohort study. Participants: One professional Australian football team over two playing seasons. Methods: For every game, the team coach rated player performance proportional to time spent on the ground playing (an integer score out of a maximum of 10). Player performance ratings were compared pre- and post-Hamstring Muscle strain injury to assess player performance upon return to sport. Results: Thirteen athletes had Hamstring injuries and the required player ratings were available. The mean player performance rating for the entire playing season in which the player was injured was 6.9. The mean player performance rating for the two games prior to injury was 6.8 as opposed to 5.4 for the two games after return to sport. Athletes had a significantly lower player performance rating immediately upon return to sport when compared to ratings for the entire season (p < 0.001) and when compared to ratings from the two games prior to injury (p < 0.001). Conclusions: Following return to sport from Hamstring injury, player performance as assessed by the team coach is reduced. This suggests that some athletes may return
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assessment of physical examination and magnetic resonance imaging findings of Hamstring injury as predictors for recurrent injury
Journal of Orthopaedic & Sports Physical Therapy, 2006Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G Barnes, G T Fon, Adrian EstermanAbstract:Study Design Prospective cohort study. Objective To examine clinical and magnetic resonance imaging (MRI) features of Hamstring Muscle injury to determine if any are predictive for recurrent injury. Background Hamstring Muscle strain injury and subsequent recurrent injury are common. Little information exists on factors that may increase the risk for recurrent injury. Methods and Measures The subjects were athletes from 3 professional Australian Rules football teams (n = 162). Anthropometric measurements, clinical signs, convalescent interval, and MRI assessment and measurement were undertaken and recorded in athletes with Hamstring Muscle strain injury. Athletes were followed for the presence, or absence, of recurrent injury to the same-side posterior thigh over the same and subsequent playing seasons. Results Thirty athletes met criteria for Hamstring injury. Twelve (40%) of 30 athletes had recurrent injury within the same season, with an additional 7 athletes having recurrent injury in the subsequent s...
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the effect of sports specific training on reducing the incidence of Hamstring injuries in professional australian rules football players
British Journal of Sports Medicine, 2005Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G BarnesAbstract:Objectives: To assess in a single team of Australian Rules football players the effect of a specific intervention program on the incidence and consequence of Hamstring Muscle strain injuries. Method: A prospective study was performed with a single team being followed for four playing seasons for Hamstring injury. Magnetic resonance imaging was used to confirm the diagnosis of Hamstring Muscle injury. After two playing seasons an intervention program was implemented with the number of athletes with Hamstring injury, competition days missed, and incidence of Hamstring match injuries per 1000 h of playing time being compared pre- and post-intervention. The intervention program involved stretching whilst fatigued, sport specific training drills, and an emphasis on increasing the amount of high intensity anaerobic interval training. Results: In the seasons prior to the intervention, nine and 11 athletes sustained Hamstring injury compared to two and four following intervention. Competition days missed reduced from 31 and 38 to 5 and 16 following intervention and match incidence decreased from 4.7 to 1.3 per 1000 h of playing time. A beneficial effect was demonstrated with a smaller number of players having Hamstring injuries (p = 0.05), a lower number of competition games missed being recorded (p Conclusions: Increasing the amount of anaerobic interval training, stretching whilst the Muscle is fatigued, and implementing sport specific training drills resulted in a significant reduction in the number and consequences of Hamstring Muscle strain injuries.
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diagnostic and prognostic value of clinical findings in 83 athletes with posterior thigh injury comparison of clinical findings with magnetic resonance imaging documentation of Hamstring Muscle strain
American Journal of Sports Medicine, 2003Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G BarnesAbstract:BackgroundLittle is known about the clinical features of posterior thigh injuries and their contribution to accurate diagnosis and prognostic assessment of Hamstring Muscle strain injury.HypothesesThe clinical features of posterior thigh injury can be used to diagnose Hamstring Muscle strain and to predict duration of absence from competition.Study DesignProspective clinical study.MethodsFor two playing seasons, the clinical features of posterior thigh injury, timing of injury, and playing days lost were recorded for Australian Rules football players. Magnetic resonance imaging was used to confirm Hamstring Muscle injury.ResultsPosterior thigh injuries associated with pain and tenderness were recorded for 83 players, with magnetic resonance imaging confirming Hamstring injury in 68 (82%). Most of the Hamstring injuries were sudden onset (62; 91%) and occurred after a significant warm-up period (57; 84%). Of the patients whose injuries were sudden onset and occurred after the warm-up period (N = 59), 57 (9...
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clinical risk factors for Hamstring Muscle strain injury a prospective study with correlation of injury by magnetic resonance imaging
British Journal of Sports Medicine, 2001Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G Barnes, G T Fon, A J SprigginsAbstract:Objective—To prospectively establish risk factors for Hamstring Muscle strain injury using magnetic resonance imaging (MRI) to define the diagnosis of posterior thigh injury. Method—In a prospective cohort study using two elite Australian Rules football clubs, the anthropometric characteristics and past clinical history of 114 athletes were recorded. Players were followed throughout the subsequent season, with posterior thigh injuries being documented. Hamstring intramuscular hyperintensity on T2 weighted MRI was required to meet our criteria for a definite Hamstring injury. Statistical associations were sought between anthropometric and previous clinical characteristics and Hamstring Muscle injury. Results—MRI in 32 players showed either Hamstring injury (n = 26) or normal scans (n = 6). An association existed between a Hamstring injury and each of the following: increasing age, being aboriginal, past history of an injury to the posterior thigh or knee or osteitis pubis (all p<0.05). These factors were still significant when players with a past history of posterior thigh injury (n = 26) were excluded. Previous back injury was associated with a posterior thigh injury that looked normal on MRI scan, but not with an MRI detected Hamstring injury. Conclusions—Hamstring injuries are common in Australian football, and previous posterior thigh injury is a significant risk factor. Other factors, such as increasing age, being of aboriginal descent, or having a past history of knee injury or osteitis pubis, increase the risk of Hamstring strain independently of previous posterior thigh injury. However, as the numbers in this study are small, further research is needed before definitive statements can be made. (Br J Sports Med 2001;35:435‐440)
Per Aagaard - One of the best experts on this subject based on the ideXlab platform.
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the influence of Hamstring Muscle peak torque and rate of torque development for sprinting performance in football players a cross sectional study
International Journal of Sports Physiology and Performance, 2019Co-Authors: Lasse Ishoi, Per Aagaard, Mathias F Nielsen, Kasper B Thornton, Kasper Krommes, Per Holmich, Kristian ThorborgAbstract:Purpose: To investigate the association between Hamstring Muscle peak torque and rapid force capacity (rate of torque development, RTD) vs sprint performance in elite youth football players. Method...
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asymmetry and thigh Muscle coactivity in fatigued anterior cruciate ligament reconstructed elite skiers
Medicine and Science in Sports and Exercise, 2017Co-Authors: Matthew J Jordan, Per Aagaard, Walter HerzogAbstract:ABSTRACTPurposeThe acute effects of fatigue on functional interlimb asymmetry and quadriceps/Hamstring Muscle activity levels, including preparatory coactivation during squat jump takeoff and landing, were evaluated in elite alpine ski racers with/without anterior cruciate ligament reconstruction (A
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viscoelastic response to repeated static stretching in the human Hamstring Muscle
Scandinavian Journal of Medicine & Science in Sports, 2007Co-Authors: S P Magnusson, Per Aagaard, Erik B Simonsen, Gilbert W Gleim, Malachy P Mchugh, Michael KjaerAbstract:The purpose of this study was (1) to evaluate the reproducibility of a new method of measuring passive resistance to stretch in the human Hamstring Muscle group, in vivo, using a test re-test protocol and 2) to examine the effect of repeated stretches. Passive resistance offered by the Hamstring Muscle group during knee extension was measured in 10 subjects as knee flexion moment (Nm) using a KinCom dynamometer. The knee was passively extended at 5 deg/s to the final position where it remained stationary for 90 s (static phase). EMG of the Hamstring Muscle was also measured. The test re-test protocol included 2 tests (tests 1 and 2) administered 1 h apart. On a separate occasion 5 consecutive static stretches were administered (stretches 1-5) separted by 30 s. Stretch 6 was administered one hour after stretch 5. In the static phase passive resistance did not differ between test 1 and test 2. Resistance declined in both tests 1 and 2, whereas EMG activity remained unchanged. The decline in resistance was significant up to 45 s. For the repeated stretches there was an effect of time (90 s) and stretch (1-5) with a significant interaction i.e., resistance diminished with stretches, and the 90-s decline was less as more stretches were performed. Passive resistance in stretch 6 was lower than in stretch 1. The present study has demonstrated a reliable method for studying resistance to stretch of the human Hamstring Muscle group. A viscoelastic response of the human Hamstring Muscle was shown. With 5 repeated stretches, resistance to stretch diminished and each stretch exibited a viscoelastic response, albeit less with each subsequent stretch. The effect of 5 repeated stretches was significant 1 h later.
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passive energy return after repeated stretches of the Hamstring Muscle tendon unit
Medicine and Science in Sports and Exercise, 2000Co-Authors: S P Magnusson, Per Aagaard, Johnny NielsonAbstract:MAGNUSSON, S. P., P. AAGAARD, and J. J. NIELSON. Passive energy return after repeated stretches of the Hamstring Muscle-tendon unit. Med. Sci. Sports Exerc., Vol. 32, No. 6, pp. 1160–1164, 2000. It has been shown that five repetitive static stretches of human Hamstring Muscle, each lasting 90 s and
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biomechanical responses to repeated stretches in human Hamstring Muscle in vivo
American Journal of Sports Medicine, 1996Co-Authors: S P Magnusson, Per Aagaard, Erik B Simonsen, Michael KjaerAbstract:To examine stiffness, energy, and passive torque in the dynamic and static phases of a stretch maneuver in the human Hamstring Muscle in vivo we used a test- retest protocol and a repeated stretches protocol. Re sistance to stretch was defined as passive torque (in newton-meters) offered by the Hamstring Muscle group during passive knee extension as measured using an isokinetic dynamometer with a modified thigh pad. In 13 uninjured subjects, the knee was passively ex tended to a predetermined final position (0.0875 rad/ sec, dynamic phase) where it remained stationary for 90 seconds (static phase). The test-retest protocol in cluded two tests administered 1 hour apart. On a sep arate occasion, five consecutive static stretches were administered separated by 30 seconds and followed by a sixth stretch 1 hour later. For the test-retest phase, stiffness and energy in the dynamic phase and passive torque in the static phase did not differ and yielded correlations of r = 0.91 to 0.99. During the static phase, p...
John P Slavotinek - One of the best experts on this subject based on the ideXlab platform.
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assessment of player performance following return to sport after Hamstring Muscle strain injury
Journal of Science and Medicine in Sport, 2006Co-Authors: Geoffrey M Verrall, Y Kalairajah, John P Slavotinek, A J SprigginsAbstract:Summary Objective: To determine if there is any decrease in playing performance of athletes following return to sport after recovery from Hamstring Muscle strain injury. Design: Prospective cohort study. Participants: One professional Australian football team over two playing seasons. Methods: For every game, the team coach rated player performance proportional to time spent on the ground playing (an integer score out of a maximum of 10). Player performance ratings were compared pre- and post-Hamstring Muscle strain injury to assess player performance upon return to sport. Results: Thirteen athletes had Hamstring injuries and the required player ratings were available. The mean player performance rating for the entire playing season in which the player was injured was 6.9. The mean player performance rating for the two games prior to injury was 6.8 as opposed to 5.4 for the two games after return to sport. Athletes had a significantly lower player performance rating immediately upon return to sport when compared to ratings for the entire season (p < 0.001) and when compared to ratings from the two games prior to injury (p < 0.001). Conclusions: Following return to sport from Hamstring injury, player performance as assessed by the team coach is reduced. This suggests that some athletes may return
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assessment of physical examination and magnetic resonance imaging findings of Hamstring injury as predictors for recurrent injury
Journal of Orthopaedic & Sports Physical Therapy, 2006Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G Barnes, G T Fon, Adrian EstermanAbstract:Study Design Prospective cohort study. Objective To examine clinical and magnetic resonance imaging (MRI) features of Hamstring Muscle injury to determine if any are predictive for recurrent injury. Background Hamstring Muscle strain injury and subsequent recurrent injury are common. Little information exists on factors that may increase the risk for recurrent injury. Methods and Measures The subjects were athletes from 3 professional Australian Rules football teams (n = 162). Anthropometric measurements, clinical signs, convalescent interval, and MRI assessment and measurement were undertaken and recorded in athletes with Hamstring Muscle strain injury. Athletes were followed for the presence, or absence, of recurrent injury to the same-side posterior thigh over the same and subsequent playing seasons. Results Thirty athletes met criteria for Hamstring injury. Twelve (40%) of 30 athletes had recurrent injury within the same season, with an additional 7 athletes having recurrent injury in the subsequent s...
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the effect of sports specific training on reducing the incidence of Hamstring injuries in professional australian rules football players
British Journal of Sports Medicine, 2005Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G BarnesAbstract:Objectives: To assess in a single team of Australian Rules football players the effect of a specific intervention program on the incidence and consequence of Hamstring Muscle strain injuries. Method: A prospective study was performed with a single team being followed for four playing seasons for Hamstring injury. Magnetic resonance imaging was used to confirm the diagnosis of Hamstring Muscle injury. After two playing seasons an intervention program was implemented with the number of athletes with Hamstring injury, competition days missed, and incidence of Hamstring match injuries per 1000 h of playing time being compared pre- and post-intervention. The intervention program involved stretching whilst fatigued, sport specific training drills, and an emphasis on increasing the amount of high intensity anaerobic interval training. Results: In the seasons prior to the intervention, nine and 11 athletes sustained Hamstring injury compared to two and four following intervention. Competition days missed reduced from 31 and 38 to 5 and 16 following intervention and match incidence decreased from 4.7 to 1.3 per 1000 h of playing time. A beneficial effect was demonstrated with a smaller number of players having Hamstring injuries (p = 0.05), a lower number of competition games missed being recorded (p Conclusions: Increasing the amount of anaerobic interval training, stretching whilst the Muscle is fatigued, and implementing sport specific training drills resulted in a significant reduction in the number and consequences of Hamstring Muscle strain injuries.
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diagnostic and prognostic value of clinical findings in 83 athletes with posterior thigh injury comparison of clinical findings with magnetic resonance imaging documentation of Hamstring Muscle strain
American Journal of Sports Medicine, 2003Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G BarnesAbstract:BackgroundLittle is known about the clinical features of posterior thigh injuries and their contribution to accurate diagnosis and prognostic assessment of Hamstring Muscle strain injury.HypothesesThe clinical features of posterior thigh injury can be used to diagnose Hamstring Muscle strain and to predict duration of absence from competition.Study DesignProspective clinical study.MethodsFor two playing seasons, the clinical features of posterior thigh injury, timing of injury, and playing days lost were recorded for Australian Rules football players. Magnetic resonance imaging was used to confirm Hamstring Muscle injury.ResultsPosterior thigh injuries associated with pain and tenderness were recorded for 83 players, with magnetic resonance imaging confirming Hamstring injury in 68 (82%). Most of the Hamstring injuries were sudden onset (62; 91%) and occurred after a significant warm-up period (57; 84%). Of the patients whose injuries were sudden onset and occurred after the warm-up period (N = 59), 57 (9...
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clinical risk factors for Hamstring Muscle strain injury a prospective study with correlation of injury by magnetic resonance imaging
British Journal of Sports Medicine, 2001Co-Authors: Geoffrey M Verrall, John P Slavotinek, Peter G Barnes, G T Fon, A J SprigginsAbstract:Objective—To prospectively establish risk factors for Hamstring Muscle strain injury using magnetic resonance imaging (MRI) to define the diagnosis of posterior thigh injury. Method—In a prospective cohort study using two elite Australian Rules football clubs, the anthropometric characteristics and past clinical history of 114 athletes were recorded. Players were followed throughout the subsequent season, with posterior thigh injuries being documented. Hamstring intramuscular hyperintensity on T2 weighted MRI was required to meet our criteria for a definite Hamstring injury. Statistical associations were sought between anthropometric and previous clinical characteristics and Hamstring Muscle injury. Results—MRI in 32 players showed either Hamstring injury (n = 26) or normal scans (n = 6). An association existed between a Hamstring injury and each of the following: increasing age, being aboriginal, past history of an injury to the posterior thigh or knee or osteitis pubis (all p<0.05). These factors were still significant when players with a past history of posterior thigh injury (n = 26) were excluded. Previous back injury was associated with a posterior thigh injury that looked normal on MRI scan, but not with an MRI detected Hamstring injury. Conclusions—Hamstring injuries are common in Australian football, and previous posterior thigh injury is a significant risk factor. Other factors, such as increasing age, being of aboriginal descent, or having a past history of knee injury or osteitis pubis, increase the risk of Hamstring strain independently of previous posterior thigh injury. However, as the numbers in this study are small, further research is needed before definitive statements can be made. (Br J Sports Med 2001;35:435‐440)
