Publications by authors named "Matt Greig"

59 Publications

Isokinetic profiling of elite youth footballers: informing selection of a practicable and efficacious isokinetic screening test.

Res Sports Med 2021 Jun 23:1-12. Epub 2021 Jun 23.

Sports Injury Research Group, Department of Sport & Physical Activity, Edge Hill University, Ormskirk, UK.

Isokinetic dynamometry represents the clinical gold standard for strength assessment but testing lack consensus. Elite youth football players (n = 28) completed 20 repetitions (analysed as four epochs) of eccentric knee flexor (eccKF) and concentric knee extensor (conKE) trials at 60, 180 and 270°∙s, quantifying peak torque (PT) and functional range (FR). There was a significant (P < 0.001) main effect for fatigue and angular velocity in conKE PT; eccKF PT was across epoch (P = 0.35) and velocity (P = 0.12) and a velocity epoch interaction highlighted more repetitions were required to elicit fatigue as velocity increased. FR decreased with fatigue (P < 0.001) and velocity (P < 0.01) in conKE and eccKF, indicative of a narrowing of the strength curve. Clinical interpretation advocates an isokinetic test comprising at least 15 reps at a velocity ≥ 180°∙s and analysis beyond the peak of the strength curve (PT) to inform clinical reasoning and individualized exercise prescription.
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http://dx.doi.org/10.1080/15438627.2021.1943392DOI Listing
June 2021

Within- and between-day loading response to ballet choreography.

Res Sports Med 2021 Jun 4:1-12. Epub 2021 Jun 4.

Sports Injuries Research Group, Department of Sport & Physical Activity, Edge Hill University, Ormskirk, Lancashire, UK.

Overuse pathologies are prevalent in ballet injury. Ten amateur ballet dancers (age: 23.20 ± 3.08 years) completed a progressive 5-stage choreographed routine on two consecutive days. Tri-axial accelerometers positioned at C7 and the dominant and non-dominant lower-limb were used to calculate accumulated PlayerLoad (PL) and uni-axial contributions of the anterior-posterior (PL), medial-lateral (PL), and vertical (PL) planes. PL increased significantly (p = 0.001) as a function of exercise duration within-trial, however there was no significant change between trials (p = 0.18). PL at C7 was significantly (p = 0.001) lower than both lower-limbs, with no bilateral asymmetry evident (p = 0.97). Planar contributions to PL were significantly greater in PL than PL and PL (p = 0.001). PlayerLoad demonstrated within-trial sensitivity to the progressive routine, however no residual fatigue effect was observed between trials. The results of this study suggest that accelerometers have efficacy in athlete monitoring and injury screening protocols, however unit placement should be considered for practical interpretation.
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http://dx.doi.org/10.1080/15438627.2021.1929223DOI Listing
June 2021

Effect of Kinesiology Tape on Tri-Axial Accelerometry During the Dance Aerobic Fitness Test.

J Dance Med Sci 2021 Sep 3;25(3):191-199. Epub 2021 Jun 3.

Department of Sport & Physical Activity, Edge Hill University, Ormskirk, Lancashire, United Kingdom.

Objectives: Kinesiology tape (KT) is thought to provide greater mechanical support during physical activity, however, there is a paucity of research investigating its application in dance. The study aimed to determine whether KT reduces PlayerLoad (PL) during the Dance Aerobic Fitness Test (DAFT) in addition to examining the relative sensitivity of accelerometer site locations.
Methods: University-level dancers (N = 11; age 18 ± 0.45 years, height 168.17 ± 12.25 cm, body mass 57.50 ± 9.91 kg) participated in two trials of the DAFT protocol in two conditions: no tape (NT) and kinesiology tape (KT). Global positioning systems (GPS) and accelerometer units were attached onto the seventh vertebra (C7) at the mid-scapula region and lower limb (LL) located at the midgastrocnemius of the dominant leg calculating measurements of triaxial (PL) and uniaxial measures (anteroposterior [PL], mediolateral [PL], and vertical [PL]) measures of PlayerLoad during the DAFT.
Results: No significant main effect was observed for the taping condition in all measures of PlayerLoad (P > 0.10). A significant main effect (p < 0.01) was observed for unit location and time, with greater loading at the LL compared to C7 and during each consequent stage of the DAFT. No significant (p > 0.52) location*taping, nor location*taping*time (p > 0.36) interactions were observed for all variables measured.
Conclusions: Kinesiology tape does not reduce loading patterns in healthy dancers during a fatigue protocol. However, triaxial accelerometers provide adequate sensitivity when detecting changes in loading, suggesting the LL may be deemed as a more relevant method of monitoring training load in dancers.
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http://dx.doi.org/10.12678/1089-313X.091521dDOI Listing
September 2021

The Temporal Pattern of Recovery in Directional Dynamic Stability Post Football-Specific Fatigue.

J Sport Rehabil 2021 May 28:1-6. Epub 2021 May 28.

Background: Rising injury rates within football require further understanding of the etiological risk factors associated with lower-limb injury.

Aim: To examine the temporal pattern of recovery of directional dynamic stability measures post football-specific fatigue.

Methods: Eighteen male elite footballers completed baseline assessments of directional dynamic stability measures (Overall Stability Index, anterior-posterior stability [A-P], medial-lateral stability [M-L] on level 1 of the Biodex Stability System). Post Soccer-Specific Aerobic Field Test90 measures were repeated immediately, +24 hours, +48 hours, and +72 hours. The main effects for the recovery time and direction of stability were supplemented by regression modeling to describe the temporal pattern of recovery.

Results: Significant main effects for time were identified for all directions of stability (Overall Stability Index, A-P, and M-L) up to +48 hours postexercise (P ≤ .05). The quadratic pattern of temporal recovery highlights a minimum of 37.55 to 38.67 hours and maximum of 75.09 to 77.33 hours. Additionally, a main effect for direction of stability was observed, with significant differences identified between A-P and M-L stability at all time points (P ≤ .001).

Conclusions: Reductions in directional dynamic stability +48 hours postfatigue highlight implications for training design, recovery strategies, and injury management for performance practitioners. Interestingly, A-P stability has been highlighted as being significantly reduced compared with M-L stability at all time points, regardless of the fatigue exposure. Practitioners should consider the reduction of stability in this plane in relation to common mechanisms of injury in the knee to inform injury-risk-reduction strategies.
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http://dx.doi.org/10.1123/jsr.2020-0284DOI Listing
May 2021

The prevalence of pre-conditioning and recovery strategies in senior elite and non-elite amateur boxing.

Phys Sportsmed 2021 May 27:1-9. Epub 2021 May 27.

Sports Injury Research Group, Sport and Physical Activity Department, Edge Hill University, Ormskirk, Lancashire, UK.

Objectives: A variety of acute strategies around competition are used to prepare and promote physical and mental restoration in athletes. However, to date, no research exists on the prevalence of such methods in amateur boxing. Therefore, this study aimed to 1) examine the prevalence of pre-conditioning and recovery strategies in amateur boxing; 2) ascertain whether this was discriminated against at competitor level.

Methods: This study surveyed 101 senior amateur boxers (Senior Elite SEB n = 59; Senior Development SDB n = 42), on their application and perceptions of pre-conditioning and recovery strategies.

Results: The reported findings determined a significantly greater number of SEB performed resistance priming activity up to 48 hours prior to competition (11, 19% vs 2, 5%; P = 0.040), and post-activation performance enhancement (PAPE) activity in the pre-competition warm-up (18, 31% vs 1, 2%; P < 0.001), compared to SDB. Likewise, SEB reported they were also significantly more likely to utilize massage (SEB 35, 59%, SDB 11, 29%, P = 0.001) and cold-water immersion (CWI) (SEB 28, 47%, SDB 10, 29%, P = 0.016) as recovery modes, compared to their SDB counterparts.

Conclusions: This study was the first to provide data on the use of PAPE, priming and recovery methods around amateur boxing bouts. Increased access to multi-disciplinary staff could be expected in SEB, possibly explaining the greater prevalence of evidence-based methods around competition. Once athlete responsiveness to PAPEand longer-term priming methods are initially assessed, these strategies could be implemented to improve punch-specific performance, though more research is needed on their efficacy. Likewise, boxers could utilize evidence-based recovery modes where possible, with increased importance during repeat-bout scenarios, such as domestic tournaments. Coaches and practitioners may use this data to implement pre-conditioning and recovery strategies, to optimize performance and reduce the risk of injury of amateur boxers.
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http://dx.doi.org/10.1080/00913847.2021.1931525DOI Listing
May 2021

Rehabilitation and successful return to play of a 17-year old elite soccer player with juvenile osteochondritis dissecans trochlear groove lesion of the knee: A case report.

Res Sports Med 2020 Dec 1:1-10. Epub 2020 Dec 1.

Sports Injuries Research Group, Edge Hill University, Ormskirk, UK.

This case summarizes the rehabilitation and return to play management of a 17-year-old elite male soccer player who required surgical stabilization of an Osteochondritis Dissecans (OCD) lesion of the trochlea groove. Trochlea groove lesions represent <1% of OCD cases, resulting in limited evidence to inform practice. The case was initially identified as antalgic running gait, and at this point the player revealed progressively worsening knee pain (over preceding 2 months) which presented as patellofemoral pain with a small knee effusion and quadriceps atrophy present on assessment. No improvement in symptoms after 2 weeks of unloading (no running) and traditional patellofemoral treatment prompted magnetic resonance imaging and computed tomography scans to inform surgical intervention. We present a summary of the four-stage rehabilitation process defined by objective assessments, resulting in a successful return-to-play 24 weeks post-surgery. This case advocates consideration of OCD in the assessment of persistent knee pain in young athletes.
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http://dx.doi.org/10.1080/15438627.2020.1853543DOI Listing
December 2020

Association of Skeletal Maturity and Injury Risk in Elite Youth Soccer Players: A 4-Season Prospective Study With Survival Analysis.

Orthop J Sports Med 2021 Mar 31;9(3):2325967121999113. Epub 2021 Mar 31.

Department of Sport and Physical Activity, Edge Hill University, Ormskirk, UK.

Background: The association between injury risk and skeletal maturity in youth soccer has received little attention.

Purpose: To prospectively investigate injury patterns and incidence in relation to skeletal maturity in elite youth academy soccer players and to determine the injury risks associated with the skeletal maturity status, both overall and to the lower limb apophysis.

Study Design: Descriptive epidemiology study.

Methods: All injuries that required medical attention and led to time loss were recorded prospectively during 4 consecutive seasons in 283 unique soccer players from U-13 (12 years of age) to U-19 (18 years). The skeletal age (SA) was assessed in 454 player-seasons using the Fels method, and skeletal maturity status (SA minus chronological age) was classified as follows: late, SA >1 year behind chronological age; normal, SA ±1 year of chronological age; early, SA >1 year ahead of chronological age; and mature, SA = 18 years. An adjusted Cox regression model was used to analyze the injury risk.

Results: A total of 1565 injuries were recorded; 60% were time-loss injuries, resulting in 17,772 days lost. Adjusted injury-free survival analysis showed a significantly greater hazard ratio (HR) for different status of skeletal maturity: early vs normal (HR = 1.26 [95% CI, 1.11-1.42]; < .001) and early vs mature (HR = 1.35 [95% CI, 1.17-1.56]; < .001). Players who were skeletally mature at the wrist had a substantially decreased risk of lower extremity apophyseal injuries (by 45%-61%) compared with late ( < .05), normal ( < .05), and early ( < .001) maturers.

Conclusion: Musculoskeletal injury patterns and injury risks varied depending on the players' skeletal maturity status. Early maturers had the greatest overall adjusted injury risk. Players who were already skeletally mature at the wrist had the lowest risk of lower extremity apophyseal injuries but were still vulnerable for hip and pelvis apophyseal injuries.
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http://dx.doi.org/10.1177/2325967121999113DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8020116PMC
March 2021

The Influence of Injury History on Countermovement Jump Performance and Movement Strategy in Professional Soccer Players: Implications for Profiling and Rehabilitation Foci.

J Sport Rehabil 2021 Jan 25;30(5):768-773. Epub 2021 Jan 25.

Context: Professional soccer players who have sustained a lower limb injury are up to 3× more likely to suffer a reinjury, often of increased severity. Previous injury has been shown to induce compensatory strategies during neuromuscular screening tests, which might mask deficits and lead to misinterpretation of readiness to play based on task outcome measures.

Objective: To investigate the influence of previous injury in professional soccer players on countermovement jump (CMJ) performance and movement strategy.

Design: Cross-sectional.

Setting: Professional soccer club competing in the English Championship (tier 2). Patients (or Other Participants): Outfield players with a minimum of 6 years as a professional.

Intervention(s): Players were categorized as previously injured (n = 10) or not injured (n = 10). All players completed double- and single-leg CMJ trials.

Main Outcome Measures: CMJ performance was quantified as jump height and flight time:contraction time ratio. CMJ movement strategy was quantified as force-time history, differentiating eccentric and concentric phases and CMJ depth.

Results: Double-leg CMJ was not sensitive to previous injury in performance or movement strategy. In contrast, single-leg CMJ performance was impaired in players with previous injury, who generated significantly lower eccentric and concentric peak force and rate of force development, and a deeper countermovement. Impaired single-leg CMJ performance was also evident in the nonaffected limb of previously injured players, suggesting cross-contamination. Hierarchical ordering revealed that the eccentric phase of the CMJ contributed little to performance in previously injured players. In noninjured players, the eccentric rate of force development and concentric peak force were able to account for up to 89% of the variation in CMJ performance.

Conclusions: Single-leg CMJ is advocated for player profiling, being more sensitive to previous injury, and negating the opportunity for interlimb compensation strategies. Movement strategy deficits in previously injured players suggest rehabilitation foci specific to eccentric force development.
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http://dx.doi.org/10.1123/jsr.2020-0243DOI Listing
January 2021

Factors influencing optimum countermovement jump performance and movement strategy in Championship professional football players: implications for player profiling.

Res Sports Med 2020 Dec 10:1-11. Epub 2020 Dec 10.

Sports Injuries Research Group, Edge Hill University, Ormskirk, UK.

Single leg countermovement jump (CMJ) is a common profiling test influenced by sport, age, sex and playing level. Controlling for these confounding variables, outfield players from an English Championship squad (n = 36) were retrospectively categorized as best (n = 10) or worst (n = 10), based on mean single leg CMJ height and flight time:contraction time ratio. Movement strategy was quantified as force-time history metrics differentiating eccentric and concentric phases. Jump height revealed that best performers elicited greater rate of force development in both phases (P ≤ 0.033), with concentric impulse the strongest predictor of performance. Time ratio also differentiated best performers as utilizing a shallower (P = 0.002) countermovement, with concentric rate of force development the strongest predictor of good performance. Successful jump height performance can mask ineffectual eccentric and stretch shortening cycle neuromuscular characteristics. Time ratio is therefore advocated as the key performance indicator, with movement strategy prioritized over gross outcome measures.
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http://dx.doi.org/10.1080/15438627.2020.1860049DOI Listing
December 2020

Injury incidence and burden in a youth elite football academy: a four-season prospective study of 551 players aged from under 9 to under 19 years.

Br J Sports Med 2021 May 16;55(9):493-500. Epub 2020 Nov 16.

Department of Sport and Physical Activity, Edge Hill University, Ormskirk, UK.

Objective: Investigate the incidence and burden of injuries by age group in youth football (soccer) academy players during four consecutive seasons.

Methods: All injuries that caused time-loss or required medical attention (as per consensus definitions) were prospectively recorded in 551 youth football players from under 9 years to under 19 years. Injury incidence (II) and burden (IB) were calculated as number of injuries per squad season (s-s), as well as for type, location and age groups.

Results: A total of 2204 injuries were recorded. 40% (n=882) required medical attention and 60% (n=1322) caused time-loss. The total time-loss was 25 034 days. A squad of 25 players sustained an average of 30 time-loss injuries (TLI) per s-s with an IB of 574 days lost per s-s. Compared with the other age groups, U-16 players had the highest TLI incidence per s-s (95% CI lower-upper): II= 59 (52 to 67); IB=992 days; (963 to 1022) and U-18 players had the greatest burden per s-s: II= 42.1 (36.1 to 49.1); IB= 1408 days (1373 to 1444). Across the cohort of players, contusions (II=7.7/s-s), sprains (II=4.9/s-s) and growth-related injuries (II=4.3/s-s) were the most common TLI. Meniscus/cartilage injuries had the greatest injury severity (95% CI lower-upper): II= 0.4 (0.3 to 0.7), IB= 73 days (22 to 181). The burden (95% CI lower-upper) of physeal fractures (II= 0.8; 0.6 to 1.2; IB= 58 days; 33 to 78) was double than non-physeal fractures.

Summary: At this youth football academy, each squad of 25 players averaged 30 injuries per season which resulted in 574 days lost. The highest incidence of TLI occurred in under-16 players, while the highest IB occurred in under-18 players.
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http://dx.doi.org/10.1136/bjsports-2020-102859DOI Listing
May 2021

Angle-Specific Isokinetic Metrics Highlight Strength Training Needs of Elite Youth Soccer Players.

J Strength Cond Res 2020 Nov;34(11):3258-3265

Department of Sport and Physical Activity, Sports Injury Research Group, Edge Hill University, Ormskirk, United Kingdom.

Eustace, SJ, Page, RM, and Greig, M. angle specific isokinetic metrics highlight strength training needs of elite youth soccer players. J Strength Cond Res 34(11): 3258-3265, 2020-The purpose of this study was to assess traditional and angle-specific isokinetic strength of eccentric knee flexors (eccKFs) and concentric knee extensors (conKEs) between senior professional and youth soccer players. Thirty-four male soccer players (17 senior and 17 youth) were recruited for bilateral assessments at 180, 270, and 60°·s. Peak torque (PT), dynamic control ratio (DCR), angle of peak torque (APT), functional range (FR), angle-specific torque (AST), and angle-specific DCR (DCRAST) were compared. The eccentric knee flexor (eccKF) and conKE PT (p = 0.782) and DCR (p = 0.508) were not different between groups across all angular velocities. Significant differences were identified for eccKF APT (p = 0.018) and FR (p = 0.006), DCRAST at 270°·s (p = 0.031), and in AST data recorded across angular velocities for eccKF and conKE (p = 0.003). Traditional strength measures were not sensitive to playing age, with implications for misinterpretation in training prescription. By contrast, AST data did differentiate between ages. Strength deficits that highlight the muscle contraction type, angular velocity, and joint angle can be manipulated within an individualized training intervention. Given the relevance to injury etiology, this study highlights potential implications for improved assessment strategies to inform training prescription for performance and injury prevention. Given the high number of injuries in adolescent soccer players, and in line with previous recommendations, practitioners should consider using more informed and specific strength and conditioning practices at younger ages.
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http://dx.doi.org/10.1519/JSC.0000000000002612DOI Listing
November 2020

Isokinetic ankle eversion and inversion strength profiling of female ballet dancers.

J Sports Sci 2021 Jan 26;39(1):1-9. Epub 2020 Aug 26.

Department of Sport & Physical Activity, Edge Hill University , Ormskirk, Lancashire, L39 4QP, UK.

Ankle injuries are highly prevalent in ballet, with strength highlighted as a primary risk factor. To profile ankle strength, fourteen female ballet dancers (age: 19.29 ± 1.59 years) completed an isokinetic testing protocol comprising concentric eversion (CON) and inversion (CON), and, eccentric inversion (ECC) trials at four angular velocities (30° · s, 60° · s, 90° · s, 120° · s) for both the dominant and non-dominant limb. In addition to Peak Torque (PT) and the corresponding Dynamic Control Ratios (DCRs), angle-specific derivatives of strength (AST) and Functional Range (FR) were calculated. There was no evidence of any significant bilateral strength asymmetry (p = 0.90) across all metrics, and no significant interactions with limb and contraction mode or velocity. A significant main effect for contraction mode (p = 0.001) highlighted greater ECC strength - which was maintained with increasing isokinetic velocity - in contrast to reductions in CON and CON strength. Specifically, dancers are ECC dominant at angular velocities greater than 60° · s, which is likely to be characteristic of most functional tasks. The lack of bilateral asymmetry may be attributed to dance training interventions that facilitate bilateral development, but ipsilateral mode and velocity-specific asymmetries have implications for injury risk and the training needs of female ballet dancers.
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http://dx.doi.org/10.1080/02640414.2020.1803185DOI Listing
January 2021

The cumulative and residual changes in eccentric knee flexor strength indices following soccer-specific treadmill running: Novel considerations of angle specific torque.

J Sports Sci 2020 Aug 7;38(16):1877-1885. Epub 2020 Jun 7.

Sports Injuries Research Group, Dept. Of Sport & Physical Activity, Edge Hill University , Lancashire, UK.

With potential implications for recovery and conditioning practices, the aim of this study was to assess the cumulative and residual response of angle specific eccentric knee flexor (eccKF) strength indices following soccer-specific activity. Thirteen semi-professional soccer players were therefore required to complete a 90-minute soccer-specific treadmill running. with eccKF isokinetic strength assessments completed pre-trial, immediately post-trial, and 48 hours post-trial. The strength assessments comprised the completion of 5 repetitions at angular velocities of 60 and 300 deg·s. Isokinetic data was analysed for measures of peak torque (PT), angle of peak torque (APT), functional range (FR), and angle specific torque (AST). Significant post-trial impairments were observed for measures of slow velocity PT (6.6%) and AST (12.5%). Further significant differences were observed 48 hours post-trial for PT (10.7%) and PT (12.8%) PT, APT (~15°), and AST (>13.6%). These data have implications for post exercise recovery monitoring and the prescription of recovery modalities and conditioning practices in the 2 days following match-play. The AST and APT responses highlight the importance of analysis of the entire strength-angle curve and at a range of angular velocities.
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http://dx.doi.org/10.1080/02640414.2020.1763053DOI Listing
August 2020

The Influence of Soccer Playing Surface on the Loading Response to Ankle (P)Rehabilitation Exercises.

J Sport Rehabil 2020 Mar 31:1-7. Epub 2020 Mar 31.

Context: Contemporary synthetic playing surfaces have been associated with an increased risk of ankle injury in the various types of football. Triaxial accelerometers facilitate in vivo assessment of planar mechanical loading on the player.

Objective: To quantify the influence of playing surface on the PlayerLoad elicited during footwork and plyometric drills focused on the mechanism of ankle injury.

Design: Repeated-measures, field-based design.

Setting: Regulation soccer pitches.

Participants: A total of 15 amateur soccer players (22.1 [2.4] y), injury free with ≥6 years competitive experience.

Interventions: Each player completed a test battery comprising 3 footwork drills (anterior, lateral, and diagonal) and 4 plyometric drills (anterior hop, inversion hop, eversion hop, and diagonal hop) on natural turf (NT), third-generation artificial turf (3G), and AstroTurf. Global positioning system sensors were located at C7 and the mid-tibia of each leg to measure triaxial acceleration (100 Hz).

Main Outcome Measures: PlayerLoad in each axial plane was calculated for each drill on each surface and at each global positioning system location.

Results: Analysis of variance revealed a significant main effect for sensor location in all drills, with PlayerLoad higher at mid-tibia than at C7 in all movement planes. AstroTurf elicited significantly higher PlayerLoad in the mediolateral and anteroposterior planes, with typically no difference between NT and 3G. In isolated inversion and eversion hopping trials, the 3G surface also elicited lower PlayerLoad than NT.

Conclusions: PlayerLoad magnitude was sensitive to unit placement, advocating measurement with greater anatomical relevance when using microelectromechanical systems technology to monitor training or rehabilitation load. AstroTurf elicited higher PlayerLoad across all planes and drills and should be avoided for rehabilitative purposes, whereas 3G elicited a similar mechanical response to NT.
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http://dx.doi.org/10.1123/jsr.2019-0199DOI Listing
March 2020

The Influence of Playing Surface on the Loading Response to Soccer-Specific Activity.

J Sport Rehabil 2020 11 5;29(8):1166-1170. Epub 2020 Feb 5.

Context: The influence of playing surface on injury risk in soccer is contentious, and contemporary technologies permit an in vivo assessment of mechanical loading on the player.

Objective: To quantify the influence of playing surface on the PlayerLoad elicited during soccer-specific activity.

Design: Repeated measures, field-based design.

Setting: Regulation soccer pitches.

Participants: Fifteen amateur soccer players (22.1 [2.4] y), injury free with ≥6 years competitive experience.

Interventions: Each player completed randomized order trials of a soccer-specific field test on natural turf, astroturf, and third-generation artificial turf. GPS units were located at C7 and the mid-tibia of each leg to measure triaxial acceleration (100 Hz).

Main Outcome Measures: Total accumulated PlayerLoad in each movement plane was calculated for each trial. Ratings of perceived exertion and visual analog scales assessing lower-limb muscle soreness were measured as markers of fatigue.

Results: Analysis of variance revealed no significant main effect for playing surface on total PlayerLoad (P = .55), distance covered (P = .75), or postexercise measures of ratings of perceived exertion (P = .98) and visual analog scales (P = .61). There was a significant main effect for GPS location (P < .001), with lower total loading elicited at C7 than mid-tibia (P < .001), but with no difference between limbs (P = .70). There was no unit placement × surface interaction (P = .98). There was also a significant main effect for GPS location on the relative planar contributions to loading (P < .001). Relative planar contributions to loading in the anterioposterior:mediolateral:vertical planes was 25:27:48 at C7 and 34:32:34 at mid-tibia.

Conclusions: PlayerLoad metrics suggest that playing surface does not influence mechanical loading during soccer-specific activity (not including tackling). Clinical reasoning should consider that PlayerLoad magnitude and axial contributions were sensitive to unit placement, highlighting opportunities in the objective monitoring of load during rehabilitation.
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http://dx.doi.org/10.1123/jsr.2019-0327DOI Listing
November 2020

The cumulative and residual fatigue response associated with soccer-specific activity performed on different playing surfaces.

J Sports Sci 2020 Mar 4;38(5):568-575. Epub 2020 Feb 4.

Sports Injury Research Group, Department of Sport and Physical Activity, Edge Hill University, Ormskirk, UK.

This study aimed to assess the effect of playing surface (Natural [NT] and Artificial [AT] Turf) on the fatigue response to a soccer-specific exercise protocol (SSEP). Eighteen male soccer players completed the SSEP on NT and AT with pre-, post-, and 48 h post-assessments of eccentric knee flexor (eccKF) and concentric knee extensor peak torque (PT), peak countermovement (CMJ) and squat jump (SJ) height, and Nordic hamstring break angle. No significant main effects for surface or any surface and time interactions were observed for any of the outcome measures, except for eccKF PT recorded at 3.14 rads, which was significantly lower 48 h post-trial in the AT condition (AT = 146.3 ± 20.4 Nm; NT = 158.8 ± 24.7 Nm). Main effects for time were observed between pre- and post-trial measures for eccKF PT at all angular velocities, Nordic break angle, CMJ and SJ height. Nordic break angle, and both CMJ and SJ height were significantly impaired 48 h post-trial when compared to pre-trial. The findings of the current study suggest surface dependent changes in eccKF PT which may have implications for recovery and subsequent performance after competition on AT.
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http://dx.doi.org/10.1080/02640414.2020.1717303DOI Listing
March 2020

Lumbar Spine Loading During Dressage Riding.

J Sport Rehabil 2020 Mar;29(3):315-319

Context: Lower back pain is prevalent in horse riders as a result of the absorption of repetitive and multiplanar propulsive forces from the horse. Global positioning system technology provides potential for in vivo measurement of planar loading during riding.

Objective: To quantify the uniaxial loading at the lumbar and cervicothoracic spine during dressage elements.

Design: Repeated measures, randomized order.

Setting: Equestrian arena. Patients (or Other Participants): Twenty-one female dressage riders.

Intervention(s): Each rider completed walk, rising trot, sitting trot, and canter trials in a randomized order. A global positioning system unit was placed within customized garments at C7 and L5, collecting triaxial accelerometry data at 100 Hz.

Outcome Measures: PlayerLoad based on the rate of change of acceleration and calculated in the anteroposterior (AP), mediolateral, and vertical planes during each trial.

Results: There was no significant main effect for global positioning system location in the AP (P = .76), mediolateral (P = .88), or vertical (P = .76) planes. There was a significant main effect for pace in all trials (P < .001), with successive elements eliciting significantly greater loading (P ≤ .03) in all planes in the order walk < rising trot < canter < sitting trot. There was a significant placement × element interaction only in the AP plane (P = .03) with AP loading greater at L5 during walk, rising trot, and canter trials, but greater at C7 during sitting trot.

Conclusions: The significant main effect for dressage element was indicative of greater pace of the horse, with faster pace activities eliciting greater loading in all planes. In vivo measurement of spinal accelerometry has application in the objective measurement and subsequent management of lumbar load for riders.
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http://dx.doi.org/10.1123/jsr.2019-0266DOI Listing
March 2020

Isokinetic strength differences between elite senior and youth female soccer players identifies training requirements.

Phys Ther Sport 2019 Sep 21;39:45-51. Epub 2019 Jun 21.

Sports Injuries Research Group, Department of Sport and Physical Activity, Edge Hill University, St Helens Road, Ormskirk, L39 4QP, United Kingdom. Electronic address:

Objectives: To compare traditional and angle-specific isokinetic strength of eccentric knee flexors and concentric knee extensors in female senior professional and youth soccer players.

Design: Cross-sectional study design.

Setting: University's Laboratory.

Participants: A total of 34 players (17 seniors [age 25.31 ± 4.51 years; height 167.89 ± 7.04 cm; mass 63.12 ± 7.79 kg] and 17 youths [16.91 ± 1.16 years; height 165.92 ± 4.42 cm; mass 60.07 ± 4.48 kg]) from the Women's Super League 1 completed strength assessments at 180, 270 and 60°∙s.

Main Outcome Measures: Peak torque (PT), dynamic control ratio (DCR), angle of peak torque (APT), functional range (FR), angle-specific torque (AST) and angle-specific DCR (DCR) were compared between age groups.

Results: The PT (P = 0.016) AST (P = 0.041) were significantly higher in seniors compared to youths; however APT (P = 0.141), DCR (P = 0.524) FR (P = 0.821) and DCR (P = 0.053) were not significant between playing age.

Conclusion: The use of absolute and angle-specific strength measures were able to distinguish between female playing ages, whereas DCR and DCR was unable to identify differences. The PT and AST metrics may be the most useful metrics to help identify and inform training needs, particularly in youths.
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http://dx.doi.org/10.1016/j.ptsp.2019.06.008DOI Listing
September 2019

The influence of different pelvic technical marker sets upon hip kinematics during gait.

Gait Posture 2019 06 14;71:74-78. Epub 2019 Apr 14.

Sports Injuries Research Group, Department of Sport and Physical Activity, Edge Hill University, Lancashire, UK.

Background: The pelvis is commonly tracked during three-dimensional motion analysis using markers located on the anterior and posterior superior iliac spines. However, these markers are prone to soft tissue artefact and marker occlusion, highlighting the need for alternative technical marker sets.

Research Question: How comparable are hip joint kinematics calculated using two alternative pelvic technical marker sets and a conventionally modelled pelvis?

Methods: Fourteen participants undertook 3D gait analysis, walking overground at a self-selected pace (1.38 ± 0.14 m·s), barefoot. Hip joint kinematics were compared using root mean square error (RMSE) between a conventionally tracked pelvis and two alternative technical marker sets; (1) posterior cluster and (2) additional iliac crest markers.

Results: The average RMSE in the sagittal, frontal and transverse planes was 2.5° ± 2.8°, 1.6° ± 0.4° and 0.8° ± 0.4°, respectively for the posterior cluster, and 1.3° ± 0.7°, 0.8° ± 0.3° and 1.4° ± 0.5° for the iliac crest marker set. The RMSE was significantly larger for the posterior cluster compared to the iliac crest model in the sagittal (p =  .05, d = .28) and frontal planes (p <  .001, d = 7.65). In contrast, the RMSE was significantly lower for the posterior cluster in the transverse plane (p =  .01, d = -2.85).

Significance: The findings of this study suggest that either a posterior cluster or additional iliac crest markers offer means of accurately calculating hip joint kinematics within 3° of the conventional pelvic model. Therefore, either technical marker set offers a viable alternative to the conventional pelvic model for calculating hip joint kinematics.
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http://dx.doi.org/10.1016/j.gaitpost.2019.04.012DOI Listing
June 2019

Concurrent changes in eccentric hamstring strength and knee joint kinematics induced by soccer-specific fatigue.

Authors:
Matt Greig

Phys Ther Sport 2019 May 18;37:21-26. Epub 2019 Feb 18.

Sports Injuries Research Group, Edge Hill University, St Helens Road, Ormskirk, Lancs, L39 4QP, UK. Electronic address:

Objectives: To investigate the influence of soccer-specific fatigue on concurrent changes in knee joint kinematics and hamstring strength, given the increased risk of injury during the latter stages of match-play and the prevalence of knee joint and hamstring muscular injury.

Design: Repeated measures, randomized order trials.

Setting: Laboratory.

Participants: Ten male professional soccer players.

Main Outcome Measures: Reactive inversion, eversion and neutral hop tasks were completed at 15 min intervals during a soccer-specific protocol, with touchdown knee joint kinematics in the frontal and sagittal planes calculated at 200 Hz. In a separate trial, players completed maximal eccentric knee flexions at 160°·s (reflecting average knee angular velocity in the functional task) at 15 min intervals, quantifying peak torque.

Results: All trials were characterized by knee varus at touchdown, with ∼4° greater mal-alignment elicited over the final 15 min of the protocol (P ≤ 0.05). Peak eccentric hamstring strength was significantly (P = 0.045) reduced throughout the 2nd half.

Conclusions: The coincident impairment of eccentric hamstring strength and increased knee varus at touchdown predisposes the player to injury, supporting epidemiological observations. Knee varus in these elite male players is in marked contrast to the valgus associated with ACL injury risk in female players.
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http://dx.doi.org/10.1016/j.ptsp.2019.02.003DOI Listing
May 2019

Submaximal Cricket Fast Bowling Offers a Disproportionate Reduction in Loading Versus Performance: An Alternative Workload Intervention.

J Sport Rehabil 2020 May 18;29(4):483-487. Epub 2019 Oct 18.

Context: Cricket fast bowlers are particularly susceptible to lumbar spine loading and injury. Quantitative analysis of technique typically involves laboratory-based biomechanical systems with limited ecological validity, whereas contemporary developments in global positioning satellite microtechnologies facilitate an on-field evaluation of loading.

Objective: To quantify the influence of submaximal bowling from reduced approach lengths on performance and loading.

Design: Repeated-measures, field-based design.

Setting: Regulation cricket pitch.

Participants: A total of 12 male cricket academy fast bowlers (18.7 [0.7] y), injury free with ≥3 years of competitive experience.

Interventions: Each bowler wore 2 global positioning satellite units placed at C7 and L4 to measure triaxial acceleration (100 Hz). Bowlers completed an over (6 deliveries) from a randomized 3-, 6-, 9-, and 12-stride approach.

Main Outcome Measures: Ball speed was recorded as the performance measure, with PlayerLoad in the anteroposterior, mediolateral, and vertical planes also calculated for each delivery length.

Results: In ball speed, there was a significant main effect for delivery length (P = .02), with a 3-stride approach eliciting significantly less ball speed than a 9-stride (P = .03) or 12-stride (P = .002) approach. In loading, there was a significant main effect for delivery length (P < .001) in the anteroposterior, mediolateral, and vertical planes, with loading increasing linearly as a function of delivery strides. The 6-stride approach elicited a 44% reduction in loading, with a disproportionately small 3.5% decrease in performance. There was a significant main effect for global positioning satellite location (P ≤ .023) in all planes, with L4 eliciting greater loading than C7.

Conclusions: A submaximal 6-stride approach yielded the optimum balance between reduced loading and performance inhibition. Reduced delivery length, therefore, offers an alternative to reduced overs in reducing loading in young bowlers and might also have practicable value in the rehabilitation of bowlers postinjury.
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http://dx.doi.org/10.1123/jsr.2018-0266DOI Listing
May 2020

The influence of short-term fixture congestion on position specific match running performance and external loading patterns in English professional soccer.

J Sports Sci 2019 Jun 18;37(12):1338-1346. Epub 2018 Dec 18.

b Sports Injuries Research Group, Department of Sport & Physical Activity , Edge Hill University , Ormskirk , UK.

The aim of the current study was to investigate positional specific physical performance and external load responses to short term fixture congestion in English professional soccer. A total of 515 match observations were categorised as G1: the first game in a week with >4 days following a previous game, G2: the second game in a week played <4 days since G1, and G3: the third game in a week played with <4 days between each of the previous games. Global positioning system and accelerometer-based metrics were partitioned into fifteen-minute epochs. These data were then analysed using a linear mixed model to assess both the within and between game positional differences. Total, low-intensity (<4.0 m·s), medium-intensity (MID; 4.0-5.5 m·s), and sprint distance (>7.0 m·s) were significantly different across games. No between game positional differences were identified; however, within match position specific differences were observed for measures of MID and HID. No significant differences were evident for accelerometer derived metrics between games or across positions. The current data suggests that the use of fifteen minute within game epochs enables the detection of alterations in physical output during congested schedules. The observed within game positional differences has implications for player specific conditioning and squad rotation strategies.
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http://dx.doi.org/10.1080/02640414.2018.1558563DOI Listing
June 2019

Functional Movement Screening as a Predictor of Mechanical Loading and Performance in Dancers.

J Dance Med Sci 2018 Dec;22(4):203-208

Sports Injuries Research Group, Department of Sport and Physical Activity, Edge Hill University, Ormskirk, Lancashire, United Kingdom.

Dance requires effective functional movement for the prevention of injury, with implications for the biomechanical response to performance. This study investigated the efficacy of the Functional Movement Screening (FMS) in predicting mechanical loading during the Dance Aerobic Fitness Test (DAFT). Twenty-five university dancers (19 females; age: 20.3 ± 0.94 years; height: 162.55 ± 0.05 cm; mass: 58.73 ± 6.3 kg; and 6 males; age: 21.08 ± 2.01 years; height: 175 ± 6.54 cm; mass: 68.16 ± 4.97 kg) were screened using the FMS. Subjects then completed the DAFT with a GPS-mounted triaxial accelerometer located at the cervico-thoracic junction. Accelerometry data were sampled at 100 Hz and used to calculate total accumulated PlayerLoad, Playerload medial-lateral (PL), PlayerLoad anterior-posterior (PL), and PlayerLoad vertical (PL) over the duration of the DAFT. Linear regression analysis was used to determine the strength of correlation between FMS and PlayerLoad, PL, PL, and PL, and forward stepwise hierarchical modelling was performed to establish which FMS components were the primary predictors of mechanical loading. The Deep Squat (DS) demonstrated statistical significance for PL and PL. The non-dominant Hurdle Step (HS) was a statistically significant predictor of PL. The FMS composite score was a statistically significant predictor for PL. Forward stepwise regression analysis demonstrated that DS was the sole predictor for PL and the primary predictor for PL. Non-dominant HS was identified as the primary predictor of PL. It is concluded that the DS, non-dominant HS, and the FMS composite score can be used to predict mechanical loading in performance of the DAFT, which may have implications for dance performance and injury prevention.
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http://dx.doi.org/10.12678/1089-313X.22.4.203DOI Listing
December 2018

Joint Hypermobility as a Predictor of Mechanical Loading in Dancers.

J Sport Rehabil 2020 Jan;29(1):12-22

Context: Dance requires the performance of complex movements that may exceed normal anatomical range. However, in hypermobile individuals, this may have implications for injury and performance.

Objectives: The aim of the study was to investigate the efficacy of the Beighton score (BS) in predicting mechanical loading in dancers in hypermobile and nonhypermobile dancers with consideration of accelerometer placement and lumbar flexion hypermobility.

Design: Cohort study, clinical measurement.

Setting: University.

Participants: A total of 34 dancers had their joint hypermobility assessed by the BS. Participants completed the Dance Aerobic Fitness Test with a global positioning device incorporating a triaxial accelerometer located at the cervico-thoracic junction (C7) and one at the midbelly of the gastrocnemius.

Main Outcome Measures: Accelerometry data were used to calculate PlayerLoad total, PlayerLoad medial-lateral, PlayerLoad anterior-posterior, and PlayerLoad vertical. Physiological response was measured via heart rate and fatigue response by rate of perceived exertion.

Results: The total BS was a poor predictor of all mechanical loading directions with PlayerLoad anterior-posterior C7 (r = .15) and PlayerLoad total lower limb (r = .20) the highest values. Multiple linear regression was a better predictor with values of C7 (r = .43) and lower limb (r = .37). No significant difference existed between hypermobile and nonhypermobile subjects for mechanical loading values for all stages of the Dance Aerobic Fitness Test and for heart rate and fatigue responses.

Conclusions: The BS is not a good predictor of mechanical loading which is similar in hypermobile and nonhypermobile dancers for all levels of the Dance Aerobic Fitness Test. Mechanical loading and fatigue responses are similar between hypermobile and nonhypermobile dancers.
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http://dx.doi.org/10.1123/jsr.2018-0216DOI Listing
January 2020

Acute adaptations and subsequent preservation of strength and speed measures following a Nordic hamstring curl intervention: a randomised controlled trial.

J Sports Sci 2019 Apr 27;37(8):911-920. Epub 2018 Oct 27.

a Sports Injuries Research Group, Department of Sport & Physical Activity , Edge Hill University , Ormskirk , UK.

This randomised controlled trial investigated changes in eccentric hamstring strength, 10m sprint speed, and change-of-direction (COD) performance immediately post Nordic hamstring curl (NHC) intervention and following a 3-week detraining period. Fourteen male team sports athletes were randomised to a do-as-usual control group (CG; n = 7) or to a NHC intervention group (NHC; n = 7). Isokinetic dynamometry at 180°/s evaluated eccentric hamstring strength immediately post-intervention as the primary outcome measure. Secondary outcomes included 10 m sprint time and COD. Each outcome was measured, pre, immediately post-intervention and following a 3-week detraining period. Immediately post-intervention significant group differences were observed in the NHC group for eccentric hamstring strength (31.81 Nm vs. 6.44 Nm, P = 0.001), COD (-0.12 s vs. 0.20 s; P = 0.003) and sprint (- 0.06 s vs. 0.05 s; P = 0.024) performance. Performance improvements were maintained following a detraining period for COD (-0.11 s vs. 0.20 s; P = 0.014) and sprint (-0.05 s vs. 0.03 s, P = 0.031) but not eccentric hamstring strength (15.67 Nm vs. 6.44 Nm, P = 0.145) These findings have important implications for training programmes designed to reduce hamstring injury incidence, whilst enhancing physical qualities critical to sport.
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http://dx.doi.org/10.1080/02640414.2018.1535786DOI Listing
April 2019

Physical Response to Pad- and Bag-Based Boxing-Specific Training Modalities.

J Strength Cond Res 2020 Apr;34(4):1052-1061

Department of Sport and Physical Activity, Edge Hill University, Ormskirk, Lancashire, United Kingdom.

Finlay, MJ, Greig, M, McCarthy, J, and Page, RM. Physical response to pad- and bag-based boxing-specific training modalities. J Strength Cond Res 34(4): 1052-1061, 2020-This study examined the differences in the physical response elicited from a contemporary Boxing-Specific Exercise Protocol (BSEP) performed using a punch bag and a pad routine. Fourteen male elite amateur boxers (age = 22 ± 2 years; height = 176.9 ± 7.3 cm; body mass = 78.8 ± 8.7 kg; and V[Combining Dot Above]O2max = 55.94 ± 5.96 ml·kg·min) were recruited. The BSEP comprised 3 × 3-minute rounds. Average (HRave) and peak (HRpeak) heart rate, average (V[Combining Dot Above]O2ave) and peak oxygen consumption (V[Combining Dot Above]O2peak), blood lactate (BLa) concentrations, rating of perceived exertion (RPE), and both triaxial and uniaxial PlayerLoad metrics were recorded during each trial. The PlayerLoad metrics were recorded at both the cervical and lumbar spine. BLa increased significantly across rounds, with higher values recorded in the pad trial (pad = 2.7 ± 0.8 mmol·L; bag = 2.3 ± 0.9 mmol·L). A similar response was also identified for the HRave (pad = 160 ± 9 b·min; bag = 150 ± 16 b·min) and V[Combining Dot Above]O2ave data (pad = 38.00 ± 0.31 ml·kg·min; bag = 34.40 ± 1.06 ml·kg·min). A significant main effect for time was also recorded for the RPE data; however, there were no significant differences between trials. Conversely, the triaxial (PLTotal) and medial-lateral (PLML) data were higher in the punch bag trial. There was also a main effect for time for all the PlayerLoad metrics. PLTotal, PLML, and vertical PlayerLoad were significantly higher in the lumbar region when compared with the cervical region. With implications for boxing-specific conditioning, the pad routine was more physiologically demanding, but less mechanically demanding than the bag routine.
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http://dx.doi.org/10.1519/JSC.0000000000002928DOI Listing
April 2020

The Efficacy of Lower-Limb Screening Tests in Predicting PlayerLoad Within a Professional Soccer Academy.

J Sport Rehabil 2019 Nov;28(8):860-865

Context: Training exposure has been associated with injury epidemiology in elite youth soccer, where lower-limb musculoskeletal screening is commonly used to highlight injury risk. However, there has been little consideration of the relationship between lower-limb screening and the loading response to soccer activities.

Objective: To quantify the efficacy of using screening tests to predict the loading elicited in soccer-specific activities and to develop a hierarchical ordering of musculoskeletal screening tests to identify test redundancy and inform practice.

Design: Correlational.

Setting: Professional soccer club academy.

Participants: A total of 21 elite male soccer players aged 15.7 (0.9) years.

Intervention: Players completed a battery of 5 screening tests (knee to wall, hip internal rotation, adductor squeeze, single-leg hop, and anterior reach) and a 25-minute standardized soccer session with a Global Positioning System unit placed at C7 to collect multiplanar PlayerLoad data.

Main Outcome Measures: Baseline data on each screening test, along with uniaxial PlayerLoad in the mediolateral, anteroposterior, and vertical planes.

Results: Stepwise hierarchical modeling of the screening tests revealed that dominant leg knee-to-wall distance was the most prevalent and powerful predictor of multiplanar PlayerLoad, accounting for up to 42% of variation in uniaxial loading. The adductor squeeze test was the least powerful predictor of PlayerLoad. Of note, one player who incurred a knee injury within 3 weeks of testing had shown a 20% reduction in knee-to-wall distance compared with peers, and elicited 23% greater PlayerLoad, supporting the hierarchical model.

Conclusions: There was some evidence of redundancy in the screening battery, with implications for clinical choice. Hierarchical ordering and a concurrent case study highlight dominant leg knee-to-wall distance as the primary predictor of multiaxial loading in soccer. This has implications for the design and interpretation of screening data in elite youth soccer.
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http://dx.doi.org/10.1123/jsr.2018-0175DOI Listing
November 2019

The temporal pattern of recovery in eccentric hamstring strength post-soccer specific fatigue.

Res Sports Med 2019 Jul-Sep;27(3):339-350. Epub 2018 Oct 8.

b Sport and Physical Activity , Edge Hill University , Ormskirk , England.

Eccentric hamstring strength is an aetiological risk factor for soccer injury. The temporal pattern of recovery post-exercise is critical in injury management. 18 male professional soccer players completed baseline assessments of eccentric hamstring strength at isokinetic speeds of 60, 150 and 300°· s. Post SAFT measures were repeated immediately, + 24 hrs, + 48 hrs and + 72 hrs. Main effects for recovery time and testing speed in average torque (AvT), peak torque (PT) and the corresponding angle (Ɵ) were supplemented by regression modelling to describe the temporal pattern of recovery. A main effect for isokinetic testing speed was observed in PT and AvT. A main effect for recovery time highlighted greater strength pre-exercise, with a quadratic pattern to temporal recovery highlighting minima achieved at between 40-48 hrs. Strength parameters are not fully recovered until 96 hrs post soccer specific fatigue, with implications for training design and injury management, particularly within fixture-congested periods.
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http://dx.doi.org/10.1080/15438627.2018.1523168DOI Listing
October 2019

Quantifying Functional Ankle Rehabilitation Progression Criteria Using GPS: A Preliminary Study.

J Sport Rehabil 2019 Sep;28(7):729-734

Context: Contemporary developments in Global Positioning System (GPS) technology present a means of quantifying mechanical loading in a clinical environment with high ecological validity. However, applications to date have typically focused on performance rather than rehabilitation.

Objective: To examine the efficacy of GPS microtechnology in quantifying the progression of loading during functional rehabilitation from ankle sprain injury, given the prevalence of reinjury and need for quantifiable monitoring. Furthermore, to examine the influence of unit placement on the clinical interpretation of loading during specific functional rehabilitation drills.

Design: Repeated measures.

Setting: University athletic facilities.

Participants: Twenty-two female intermittent team sports players.

Intervention: All players completed a battery of 5 drills (anterior hop, inversion hop, eversion hop, diagonal hop, and diagonal hurdle hop) designed to reflect the mechanism of ankle sprain injury, and progress functional challenge and loading.

Main Outcome Measures: GPS-mounted accelerometers quantified uniaxial PlayerLoad for each drill, with units placed at C7 and the tibia. Main effects for drill type and GPS location were investigated.

Results: There was a significant main effect for drill type (P < .001) in the mediolateral (η2 = .436), anteroposterior (η2 = .480), and vertical planes (η2 = .516). The diagonal hurdle hop elicited significantly greater load than all other drills, highlighting a nonlinear progression of load. Only the mediolateral load showed evidence of progressive increase in loading. PlayerLoad was significantly greater at the tibia than at C7 for all drills, and in all planes (P < .001, η2 ≥ .662). Furthermore, the tibia placement was more sensitive to between-drill changes in mediolateral load than the C7 placement.

Conclusions: The placement of the GPS unit is imperative to clinical interpretation, with both magnitude and sensitivity influenced by the unit location. GPS does provide efficacy in quantifying multiplanar loading during (p)rehabilitation, in a field or clinical setting, with potential in extending GPS analyses (beyond performance metrics) to functional injury rehabilitation and prevention.
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http://dx.doi.org/10.1123/jsr.2018-0045DOI Listing
September 2019

Effect of Fatigue on Functional Movement Screening Performance in Dancers.

Med Probl Perform Art 2018 09;33(3):213-219

Dep. of Sport and Physical Activity, Edge Hill University, St. Helens Road, Ormskirk, Lancs L39 4QP, UK. Tel 0044 01695 584246, fax 0044 01695 579997.

Objective: Dance is associated with a high risk of injury, with fatigue identified as a contributing factor. Functional movement screening (FMS) has been used to identify alterations in normal movement which may contribute to injury risk, though this test is not normally performed in a fatigued state. The aim of this study was to determine whether fatigue induced by the dance aerobic fitness test (DAFT) results in changes in FMS scores with implications for performance and injury risk.

Methods: Forty-one university dancers completed the FMS before and immediately after completion of the DAFT. Rate of perceived exertion and heart rate were quantified as measures of fatigue.

Results: Post-DAFT, the mean FMS composite score (15.39±1.86) was significantly less (p≤0.01) than the pre-exercise score (16.83±1.83). Element-specific analysis revealed that the deep squat, non-dominant lunge, and dominant inline lunge scores were all significantly impaired post-DAFT (all p≤0.01).

Conclusion: The identification of changes in quality of movement in a fatigued state suggests that movement screening should also be performed post-exercise to enhance screening for injury risk. The influence of dance-specific fatigue was FMS element-specific. Specifically, the deep squat and inline lunge were most susceptible to fatigue, with implications for injury risk and performance and reflective of the high level of neuromuscular control required.
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http://dx.doi.org/10.21091/mppa.2018.3032DOI Listing
September 2018
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