Dr Chris Brogden

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 ac-celerometer 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 mid-gastrocnemius of the dominant leg calculating measurements of triaxial (PLTotal) and uniaxial measures (anteroposterior [PLAP], mediolateral [PLML], and vertical [PLV]) 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.

This randomised controlled trial investigated changes in eccentric hamstring strength, 10 m 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-1 vs. 6.44 Nm-1, 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-1 vs. 6.44 Nm-1, P = 0.145) These findings have important implications for training programmes designed to reduce hamstring injury incidence, whilst enhancing physical qualities critical to sport.

Injury incidence in dance is high, in large part due to the frequency of repetitive and complex movements that require the lower limb to absorb and utilize extreme forces. The aim of this study was to quantify the biomechanical demands of the Dance Aerobic Fitness Test (DAFT) via triaxial accelerometry and utilize it to compare loading at the cervical spine and distal aspect of the lower limb. University dancers (N = 26; age: 20.0 ± 1.5 years; height: 1.61 ± 0.08 m; body mass: 58.40 ± 6.20 kg) completed two trials (one familiarization and one experimental) of the DAFT, consisting of five incremental levels of dance performance. Micromechanical electrical systems (MEMS) accelerometry was used to calculate total accumulated PlayerLoad (PL Total ) and it's uniaxial (anteroposterior [PL AP ], mediolateral [PL ML ], and vertical [PL V ]) components for each level. MEMS units were positioned at cervical vertebra 7 (C7) and the center of gastrocnemius (LL). There was a significant main effect for each level, with loading increasing in relation to exercise duration. There was also a significant main effect for anatomical placement, with higher PL Total (C7 = 41.05 ± 7.31 au; LL = 132.58 ± 35.70), PL AP (C7 = 12.96 ± 2.89 au; LL = 47.16 ± 13.18 au), and PL ML (C7 = 10.68 ± 2.15; LL = 46.29 ± 12.62 au) at LL when compared to C7, with the converse relationship for PL V (LL = 20.05 ± 3.41 au; C7 = 44.89 ± 11.22 au). Significant interactions were displayed for all PL metrics. It is concluded that triaxial PlayerLoad was sensitive enough to detect increased loading associated with increases in exercise intensity, while lower limb accelerometer placement detected higher loading in all planes. The specificity in anatomical placement has practical implications, with lower limb accelerometry recommended to assess movement strategies in that location.

Purpose To assess the residual fatigue response associated with the completion of two successive soccer-specific exercise protocols (SSEP). Methods Twenty male soccer players were pair-matched before completing SSEPs, interspersed by either 48 or 72 h. Outcome variables were measured every 15 min, and comprised uni-axial measures of PlayerLoad, mean (HR) and peak heart rate (HR peak), blood lactate concentration, mean and peak (V˙O 2peak) oxygen consumption, and rating of perceived exertion (RPE). Results No significant (P > 0.05) group interactions were identified for any outcome variables. Uni-axial (and total) PlayerLoad exhibited a significant (P < 0.05) main effect for time, with the exception of the relative contribution of medial lateral PlayerLoad™. Total PlayerLoad during the final 15 min (222.23 ± 15.16 a.u) was significantly higher than all other time points. All other outcome variables also exhibited a significant main effect for time, with HR, HR peak and V˙O 2peak also exhibiting significantly higher values in the first trial. There was also a significant (P = 0.003) trial*time interaction for RPE. Conclusions With equivalence at baseline, there was no difference in the fatigue response associated with two SSEPs interspersed by either 48 or 72 h recovery. The current study has implications for the design and micro management of training and competition schedules.

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 PlayerLoadTM (PLTOTAL) and uni-axial contributions of the anterior-posterior (PLAP), medial-lateral (PLML), and vertical (PLV) planes. PLTOTAL increased significantly (p = 0.001) as a function of exercise duration within-trial, however there was no significant change between trials (p = 0.18). PLTOTAL at C7 was significantly (p = 0.001) lower than both lower-limbs, with no bilateral asymmetry evident (p = 0.97). Planar contributions to PLTOTAL were significantly greater in PLV than PLAP and PLML (p = 0.001). PlayerLoadTM 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.

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 (CONEV) and inversion (CONINV), and, eccentric inversion (ECCINV) trials at four angular velocities (30° · s

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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, Player-load medial-lateral (PL ML ), PlayerLoad anterior-posterior (PL AP ), and PlayerLoad vertical (PL V ) over the duration of the DAFT. Linear regression analysis was used to determine the strength of correlation between FMS and PlayerLoad, PL ML , PL AP , and PL V , 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 Total and PL Total . The non-dominant Hurdle Step (HS) was a statistically significant predictor of PL MLTotal . The FMS composite score was a statistically significant predictor for PL VTotal . Forward stepwise regression analysis demonstrated that DS was the sole predictor for PL Total and the primary predictor for PL VTotal . Non-dominant HS was identified as the primary predictor of PL MLTotal . 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.

Background: The Nordic hamstring exercise (NHE) has emerged as a popular intervention for improving eccentric hamstring strength, however recent literature suggests there is a potential for an increase in injury risk during subsequent exercise. Methods: To quantify the influence of pre-exercise NHE on the electromyographical response of the hamstrings, 10 male soccer players completed an experimental trial comprising 6 sets x 5 repetitions of NHE prior to the completion of a 45 minute soccer-specific protocol. Post-exercise NHE were performed in the experimental and control (no pre-exercise NHE) trials. Electromyographic (EMG) response (integrated, mean and peak amplitude) of the biceps femoris to the pre- and post-exercise NHE and the soccer-specific exercise protocol was quantified. Results: Integrated (P= 0.025) and mean (P= 0.020) EMG elicited a significant main effect for time in the soccer-specific protocol with higher values during the first 15 mins indicative of a fatigue effect. However, there was no trial x time interaction (P ≥ 0.78). There was no difference between trials in the EMG response to pre-exercise (P≥ 0.30) or post-exercise (P≥ 0.16) NHE trials. Conclusions: Therefore, although previous studies suggest performing pre-exercise NHE might impair maximal strength metrics, the current study’s results suggest that it does not impair the electromyographical response to subsequent soccer-specific exercise or NHE repetitions.

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.

The aim of this study was to assess the physiological, perceptual, and mechanical measures associated with the completion of a simulated period of short-term soccer-specific fixture congestion. Ten male semi-professional soccer players completed three trials of a treadmill-based match simulation, with 48 hours intervening each trial. A repeated measures general linear model identified significantly (P= 0.02) lower knee flexor peak torque (PT) recorded at 300 degs∙s-1 in the second (141.27 ± 28.51 Nm) and third trials (139.12 ± 26.23 Nm) when compared to the first (154.17 ± 35.25 Nm). Similarly, muscle soreness (MS) and PT data recorded at 60 degs∙s-1 were significantly (P< 0.05) different in the third trial (MS= 42 ± 25 a.u; PT60= 131.10 ± 35.38 Nm) when compared to the first (MS= 29 ± 29 a.u; PT60= 145.61 ± 42.86 Nm). Significant (P= 0.003) differences were also observed for mean Bicep Femoris electromyography (EMGmean) between the third trial (T0-15= 126.36 ± 15.57 µV; T75-90= 52.18 ± 17.19 µV) and corresponding time points in the first trial (T0-15= 98.20 ± 23.49 µV; T75-90= 99.97 ± 39.81 µV). Cumulative increases in perceived exertion, heart rate, oxygen consumption, blood lactate concentrations, EMGmean, and PlayerLoadTM were recorded across each trial. MS and PT were also significantly different post-trial. There were however no significant main effects or interactions for the salivary Immunoglobulin A, and the medial-lateral PlayerLoadTM metrics. These data suggest a biomechanical and muscular emphasis with residual fatigue, with implications for injury risk and the development of recovery strategies.

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 non-hypermobile dancers with consideration of accelerometer placement and lumbar flexion hypermobility. Design: Cohort study, clinical measurement. Setting: University. Participants: Thirty-four dancers had their joint hypermobility assessed by the BS. Participants completed the Dance Aerobic Fitness Test (DAFT) with a Global positioning device incorporating a triaxial accelerometer located at the cervico-thoracic junction (C7) and one at the mid belly of the gastrocnemius. Main outcome measures: Accelerometry data was used to calculate PlayerLoad total, PlayerLoad medial-lateral, PlayerLoad anterior-posterior and Player Load 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 = 0.37). No significant difference existed between hypermobile and non-hypermobile subjects for mechanical loading values for all stages of the DAFT and for heart rate and fatigue responses. Conclusions: The BS is not a good predictor of mechanical loading which is similar in hypermobile and non-hypermobile dancers for all levels of the DAFT. Mechanical loading and fatigue responses are similar between hypermobile and non-hypermobile dancers.

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 48h 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 180 deg·s-1, which was significantly lower 48h 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 48h 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.

Nordic hamstring curls (NHC) are a commonly used injury intervention method in amateur team sports. Seventeen elite male academy soccer players performed an 8-week low volume NHC programme. Pre-post intervention measures of isokinetic eccentric knee flexor (KF) strength, linear speed, COD performance, hamstring muscle thickness, pennation angle and fascicle length were recorded. No significant main effects were observed for measures of isokinetic KF strength (P ≥ 0.19), linear sprint speed (P ≥ 0.47) or hamstring muscle architecture (P ≥ 0.30). However, significance was noted for improved COD performance (P < 0.01; mean difference, -0.06, p = 0.001, 95% CI = 0.03 to 0.09; d = 0.80), exceeding the minimal detectable difference (MDD = 0.05 s). A low-volume NHC intervention may contribute to significant improvements in COD ability, independent of no significant changes in eccentric KF strength, linear sprint speed or muscle architectural properties in elite youth soccer players.

Objectives: To investigate the effects of different variations of elastic therapeutic taping (ETT) on tests used to screen for ankle injury risk and function. Design: Randomized crossover. Setting: Laboratory. Participants: Twelve professional male soccer players completed three experimental trials: No tape (NT), RockTape™ (RT), and Kinesio™ Tape (KT) applied to the ankle complex. Outcome Measures: Clinical and functional ankle screening tests were used to assess the effects of ETT on measures of joint position sense, postural stability and ground reaction forces. Results: KT (P = 0.04) and RT (P = 0.01) demonstrated significant improvements in end range joint position sense. When compared to NT, RT significantly (P = 0.02) improved mid-range joint position sense at 15° and time to complete a drop landing task. No significant differences were observed for measures of postural stability (P ≥ 0.12) nor ground reaction force variables (P ≥ 0.33). Conclusions: Results advocate the use of ETT for proprioceptive and functional tasks when applied to the ankles of healthy male soccer players. However, a greater number of practical and significant differences were observed when RT only was applied, indicating that practitioners may potentially advocate the use of RT for tasks requiring proprioception and functional performance.

Dance is associated with a high risk of injury and fatigue is often a contributing factor. The Star Excursion Balance Test (SEBT) has been used to identify alterations in normal movement that may contribute to injury risk; however, there has been limited investigation of the potential effects of fatigue. The aim of this study was to explore the influence of dance-specific fatigue on SEBT performance, with implications for injury and performance in dance. Thirty-five university dancers completed the modified SEBT in anterior, posterolateral, and posteromedial directions prior to and immediately following the Dance Aerobic Fitness Test (DAFT). The SEBT was completed for dominant and non-dominant legs. Heart rate and rate of perceived exertion were quantified as measures of fatigue. Post-DAFT, the mean SEBT percentage maximized reach distances for dominant and non-dominant legs were non-significant compared to pre-DAFT scores. Lack of a main effect for exercise was observed in each of the anterior dominant and non-dominant, posterolateral dominant and non-dominant, and posteromedial dominant and non-dominant scores. It is concluded that the limited changes in the ability of dancers to perform the SEBT suggest that they were able to maintain SEBT performance in both dominant and non-dominant legs following exercise. This resistance to fatigue may demonstrate a dance-specific performance adaptation so that potential alterations in movement performance that may increase injury risk were not observed.

Isokinetic dynamometry represents the clinical gold standard for strength assessment but testing lack consensus. Elite youth male 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-1, 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 not significant across epoch (P = 0.35) and velocity (P = 0.12) and a velocity x 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-1 and analysis beyond the peak of the strength curve (PT) to inform clinical reasoning and individualized exercise prescription.

Context: Clinical and functional assessments are performed regularly in sporting environments to screen for performance deficits and injury risk. Circadian rhythms have been demonstrated to affect human performance; however, the influence of time of day on a battery of multiple ankle injury risk factors has yet to be established within athletic populations. Objectives: To investigate the influence of circadian variation on a battery of tests used to screen for ankle etiological risk factors. Design: Randomized crossover design. Setting: University laboratory. Participants: A total of 33 semiprofessional soccer players (age = 24.9 [4.4] y; height = 1.77 [0.17] m; body mass = 75.47 [7.98] kg) completed 3 randomized experimental trials (07∶00, 12∶00, and 19∶00 h). Main Outcome Measures: Trials involved the completion of a standardized test battery comprising the Biodex Stability System, Star Excursion Balance Test, isokinetic inversion: eversion ratio, joint position sense, and a drop-landing inversion cutting maneuver. Results: Repeated measures analysis of variance revealed significantly (P < .05) lower values for all Biodex Stability System indicia; overall stability index (1.10 [0.31] a.u.), anterior-posterior (0.76 [0.21] a.u.), and mediolateral (0.68 [0.23]) at 12∶00 hours when compared with 07∶00 hours (1.30 [0.45] a.u.; 0.96 [0.26] a.u.; 0.82 [0.40] a.u.), respectively. However, no significant (P ≥ .05) main effects for time of day were reported for any other test. Conclusions: Circadian influence on ankle etiological risk factors was task dependent, with measures of proprioception, strength, and Star Excursion Balance Test displaying no circadian variation, indicating no association between time of day and markers of injury risk. However, the Biodex Stability System displayed improved performance at midday, indicating postural stability tasks requiring unanticipated movements to display a time of day effect and potential increased injury risk. Consequently, time of testing for this task should be standardized to ensure correct interpretations of assessments and/or interventions.

The intermittent activity profile of soccer match play increases the complexity of the physical demands. Laboratory models of soccer match play have value in controlled intervention studies, developed around manipulations of the activity profile to elicit a desired physiological or biomechanical response. Contemporary notational analyses suggest a profile comprising clusters of repeat sprint efforts, with implications for both biomechanical and physiological load. Eighteen male soccer players completed a 90-minute treadmill protocol based on clusters of repeat sprint efforts. Each 15-minute bout of exercise was quantified for uniaxial (medial-lateral [PLML], anterior-posterior [PLAP], and vertical [PLV]) and triaxial PlayerLoad (PLTotal). The relative contributions of the uniaxial PlayerLoad vectors (PLML%, PLAP%, and PLV%) were also examined. In addition to rating of perceived exertion, the physiological response comprised heart rate, blood lactate concentration, and both peak and average oxygen consumption. Triaxial PlayerLoad increased (p = 0.02) with exercise duration (T0-15 = 206.26 ± 14.37 a.u. and T45-60 = 214.51 ± 14.97 a.u.) and remained elevated throughout the second half. This fatigue effect was evident in both the PLML and PLAP movement planes. The mean relative contributions of PLV%:PLAP%:PLML% were consistent at ∼48:28:23. The physiological response was comparable with match play, and a similar magnitude of increase at ∼5% was observed in physiological parameters. Changes in PlayerLoad might reflect a change in movement quality with fatigue, with implications for both performance and injury risk, reflecting observations of match play. The high frequency of speed change elicits a 23% contribution from mediolateral load, negating the criticism of treadmill protocols as "linear."

Poster presentation at the WiSEAN conference 2025.

Most measurements of isokinetic hamstring:quadriceps (H:Q) strength ratios are conducted using concurrent repetitions, whereby active knee extension is immediately followed by active knee flexion. To reduce the influence of the stretch-shortening cycle and limit axis misalignment, isolated repetitions have been recommended, whereby extension and flexion are completed separately. To inform screening protocols, this study examined the effect of concurrent and isolated trials on discrete and angle-specific H:Q ratios. Fifteen males (age: 27 ± 4 years; height: 184 ± 9 cm; body mass: 80 ± 9 kg) performed isokinetic tests of the knee flexors and extensors (60 °/s) using concurrent and isolated trials while sagittal kinematics were captured (100 Hz). Statistical parametric mapping enabled the effects of protocol type (concurrent vs. isolated) and axis misalignment (uncorrected vs. corrected) to be compared. Uncorrected data resulted in an underestimation of discrete conventional (−10.17%, p < 0.001) and functional (−9.21%, p < 0.05) ratios with differences being observed for all angle-specific ratios (p < 0.001). The use of concurrent repetitions resulted in a significant overestimation of the conventional H:Q ratio (+7.41%, p < 0.05) with the differences being most prevalent at more extended (24 - 45° knee flexion, p < 0.05) knee joint positions. Dynamometer users should be aware that concurrent repetitions increase the likelihood of “false negative” injury risk categorisation. Nevertheless, the common practice of using uncorrected data from concurrent repetitions does not lead to significant differences in discrete or angle-specific H:Q ratios when compared with corrected data obtained from isolated repetitions.

INTRODUCTION: Recent research suggests that return-to-play protocols may benefit from the inclusion of angle-specific hamstring:quadriceps (H:Q) ratios to accurately understand muscle balance through the ROM (Lunn et al. 2023). In undertaking angle-specific analyses, most isokinetic knee extension-flexion protocols are conducted using concurrent repetitions (CON) whereby active knee extension is immediately followed by active knee flexion. To reduce the influence of the stretch-shortening cycle and limit axis misalignment, isolated repetitions (ISO) have been recommended (Alt et al. 2014) whereby extension and flexion are completed separately. To inform athlete screening protocols, this study examined the effect of CON and ISO protocols on discrete and angle-specific hamstring:quadriceps ratios. METHODS: Fifteen healthy males (age: 27 ± 4 years; height: 184 ± 9 cm; body mass: 80 ± 9 kg) performed isokinetic tests of the knee flexors and extensors (60 deg/s) using CON and ISO repetitions while sagittal-plane kinematics were captured (100 Hz) to quantify axis misalignment. Statistical parametric mapping then enabled the effects of protocol type (CON vs. ISO) and axis misalignment (uncorrected vs. corrected data) to be compared. RESULTS: The use of uncorrected data resulted in an underestimation of discrete conventional (−10.2%, p < 0.001) and functional (−9.2%, p < 0.05) H:Q ratios with these differences being observed for all angle-specific ratios (p < 0.001). The use of concurrent repetitions resulted in a significant overestimation of the H:Q ratio (+7.4%, p < 0.05) with the differences being most prevalent at extended knee joint positions. Despite the main effect(s) of protocol type and axis misalignment, no significant interactions were observed. CONCLUSION: Practitioners should be mindful that the use of concurrent repetitions will result in a significantly higher conventional H:Q ratio which will particularly influence angle-specific ratios in more extended knee joint positions. This may increase the likelihood of “false negative” injury risk categorisation during “time-efficient” protocols involving concurrent repetitions. Whilst the use of corrected knee moment data is preferable, practitioners should be mindful that the use of isolated repetitions and corrected joint moment data does not lead to significant differences in discrete or angle-specific H:Q ratios when compared with uncorrected data obtained from concurrent repetitions.

Background Effective management of anterior cruciate ligament (ACL) injuries requires a comprehensive approach, from initial assessment, through treatment, rehabilitation, and discharge, however no gold standard care pathway exists to help guide clinicians. This case series provides an overview of current ACL injury management processes in six National Health Service (NHS) Trusts. Methods This study utilised a retrospective case series design within six NHS Trusts in the Yorkshire region of the United Kingdom. Using a standard operating procedure, each Trust selected ten consecutive ACL injured patients (≥ 16 years), managed either surgically or non-surgically. Data relating to the patient injury journey, patient and injury characteristics, key pathway events, rehabilitation management, outcome measures, and discharge, were collected. Data was anonymised and analysed using descriptive statistics. Results Reviews covered 55 patients, median age 25.5 years, (41 males, 14 females). Median time to specialist assessment from injury was 12 days (Interquartile Range [IQR] 6 to 20 days), with 43 patients managed operatively, and 12 non operatively. The median number of physiotherapy sessions was 21 (IQR 9 to 29.5), with outcome measures being variably used across Trusts. Trusts using patient reported outcome measures (PROMS) consistently with their patients provided more physiotherapy appointments (34.5 and 27) and achieved higher return to sport (RTS) rates. Time from injury to discharge varied with a median of 421 (IQR 249 to 546) days. Discharge criteria were applied inconsistently across Trusts, with 31% of cases not using specific criteria. However, Trusts using standardised discharge criteria showed better RTS outcomes, with 27 (61%) patients successfully returning to sport. Conclusions This case series review highlighted some good practice in initial ACL management across six NHS Trusts in the Yorkshire region. However, from time to MRI diagnosis to discharge, substantial variation in care is observed. Whether treated operatively or non-operatively, for patients aiming to RTS, this was achieved with greater consistency when more physiotherapy appointments were undertaken, outcome measures and PROMs were used, and specific discharge criteria was utilised. Future larger pathway investigation studies incorporating causative and predictive analysis studies on a national scale are required to determine whether similar trends are observed in a wider ACL injured population, which could help to improve national pathways for patients and clinicians working towards ensuring more positive and standardised patient-related ACL injury outcomes.

Musculoskeletal injuries are common in both general and sporting populations and contribute to significant healthcare costs, lost workdays and compromised performance of daily activity and sport. Despite various rehabilitation models being available to health and rehabilitation practitioners, there are some inconsistencies in structure, terminology and specificity across these. The current narrative review critically evaluates existing rehabilitation models, frameworks and phased approaches, identifying limitations related to structure, content and specificity. Additionally, a novel multicomponent exercise rehabilitation model is proposed which adopts a non-linear, concurrent approach to attribute development and integration of progression guidance. Using a multicomponent approach, a structured yet adaptable progression framework is provided that could help optimize rehabilitation outcomes, minimize detraining and enhance individuals’ readiness for return to sport or daily activity.

Abstract

Purpose: To (a) quantify the internal and external training load (TL) demands of professional ballet dancers; (b) explore the influence of session type, and sex on TL. Methods: Twenty-nine professional ballet dancers (men = 14; women = 15) were monitored over two weeks. Internal TL data was measured using heart rate-derived TRIMP, and external TL using PlayerLoad (PL). TL data from 303 sessions were categorised and analysed according to session type (rehearsal, class, and conditioning), and sex. Results: Dancers averaged ~4.62 per day (~ 26.1 hours/week) comprised of daily (PL: 539 AU; HR TRIMP: 314 arbitrary units (AU)) and weekly (PL: 2608 AU; HR TRIMP: 1503 AU) TL. Rehearsals had the longest duration (197 ± 66 min) but lowest load per minute. Conditioning produced the highest PL (140.1 AU, 95% CI: 120.2-160.0), while class elicited the greatest HR TRIMP (89.4 AU, 95% CI: 72.1-106.7). Session type significantly influenced TL (P = 0.004, η2 = 0.68) with small to moderate differences between rehearsal and conditioning (PL ES = 0.38; TRIMP ES = 0.49). No significant differences were observed by sex (PL, P = 0.57; TRIMP, P = 0.18). Conclusions: Conditioning sessions produced the greatest TL response and should play a key role in professional ballet dancer’s schedules. Although TL did not significantly differ by sex, the study suggests that a uniform training model may not meet individual dancer needs. These findings support the implementation of personalised monitoring and periodised scheduling strategies to optimise both artistic and physical performance in professional ballet.