Prevalence and incidence of health problems and their characteristics in Brazilian para athletes: A one-season single-center prospective pilot study.

BACKGROUND: Para athletes experience high prevalence and incidence of health problems related to sport. Despite this, there are few longitudinal studies. OBJECTIVE: To describe the characteristics, prevalence, incidence, and severity of health problems in para athletes from one of the Brazilian Paralympic Reference Centers during a sports season and to compare the prevalence of health problems between para athletics, para powerlifting, and para swimming. METHODS: This prospective pilot study was conducted from October 2019 to March 2020. The Oslo Sports Trauma Research Center Questionnaire on Health Problems was used to record injuries and illnesses every week for 24 weeks. The characteristics, prevalence, incidence, and severity of health problems were described for each modality. The prevalence of health problems was compared among the three sport modalities. RESULTS: Thirty-five para athletes participated. Most of the injuries occurred in the shoulder, and most illnesses caused respiratory and gastrointestinal symptoms. The average weekly prevalence and the incidence rate of health problems were 40.6% (95% CI 17.0-64.4) and 12.7 (95% CI 9.6-15.9) per 1000 athlete hours, respectively. Para powerlifting had the highest prevalence of all and substantial health problems; para swimming had the lowest prevalence of injuries; and para athletics had the lowest prevalence of illnesses. CONCLUSIONS: This group of Brazilian para athletes showed a high prevalence and incidence of health problems throughout the season. Para athletics, para powerlifting, and para swimming each had a different prevalence of injuries and illnesses.

Effects of Resistance Training of Upper Limb and Trunk Muscles on Soccer Instep Kick Kinematics.

The upper body and trunk muscles are crucial to perform soccer kicks. Resistance training targeting these muscles may modify the pattern adopted during kicking. This study aimed to investigate the effect of resistance training of the arm and anterior trunk muscles on instep kicking kinematics. Twenty-six male participants were randomly allocated into a training group or control group. The training group underwent resistance training of arm and trunk muscles and practiced the instep kick for 8 weeks. The control group only practiced kicking during the same period. The trunk, hip, and knee kinematics were assessed during the instep kick before and after the intervention. Kinematics were analyzed according to their data distribution with statistical parametric or nonparametric mapping. The effect of the training on the 1-repetition maximum test was analyzed using a repeated-measures multivariate analysis of variance. The training group showed greater hip extension after the training during the backswing phase (Hedge g effect size of 0.316-0.321) and increased 1-repetition maximum for all exercises. There were no other differences. The present study documented the nonlocal effect of strengthening training in which arm and trunk muscle training resulted in changes in hip kinematics during the backswing phase of the instep kick.

New Optimized Dynamic Calibration Proposition for Discretized Sensorized Insoles With Resistive Force Sensor: A Descriptive and Comparative Study.

Sensorized insoles (SIs) have been used as a wearable instrument to study human gait and have the potential to identify and predict pathologies and injuries. However, most of these sensorized insoles are only statically calibrated, relying on a scale and known weights to establish a relationship between electrical signals and the load applied on laboratory benches while ignoring the dynamic interaction between person and instrument. This study proposes and verifies a calibration method complementary to static calibration to compensate for different dynamic interactions between the insole and the individual during gait. In order to perform this comparison, a laboratory test was proposed with 32 volunteers (18 men and 14 women). Each volunteer walked on a double-belt instrumented treadmill (Bertec at 1000 Hz, Bertec Corp, Columbus, OH) while wearing an experimental resistive sensorized insole (SI). The SI data were compared with the instrumented treadmill and adjusted using an optimization algorithm to create a dynamic coefficient to complement and optimize the results. This study also verifies the impact of the method considering three different types of gait: pronated, neutral, and supinated. After using this technique and considering static calibration, the Pearson correlation coefficient between the SI and the instrumented treadmill improved by 12%.

Knee Kinetics and Kinematics of Young Asymptomatic Participants during Single-Leg Weight-Bearing Tasks: Task and Sex Comparison of a Cross-Sectional Study.

This cross-sectional study aimed to describe and compare kinetic and kinematic variables of the knee joint during stair descent, single-leg step down, and single-leg squat tasks. It also aimed to investigate potential sex difference during the tasks. Thirty young asymptomatic individuals (15 males, 15 females) were assessed during the performance of single-leg weight-bearing tasks. The kinetic and kinematic data from the knee were evaluated at the peak knee moment and at peak knee flexion. Single-leg squat presented a higher peak knee moment (2.37 Nm/kg) and the greatest knee moment (1.91 Nm/kg) at knee peak angle in the frontal plane, but the lowest knee flexion (67°) than the other two tasks (p < 0.05). Additionally, the single-leg step down task presented a higher varus knee angle (5.70°) when compared to stair descent (3.71°) (p < 0.001). No substantial sex difference could be observed. In conclusion, in asymptomatic young individuals, single-leg squats presented the greatest demand in the frontal and sagittal planes. Single-leg step down demanded a greater angular displacement than stair descent in the frontal plane. We did not identify a significant difference among the sex and studied variables.

Validity and reliability of a smartphone application for knee posture quantification and the effects of external markers on the precision of this measure.

BACKGROUND: Technological resources, such as smartphones can contribute to the quantitative assessment of posture. PURPOSES: Test the validity and reliability of using a postural assessment application to quantify the frontal plane knee posture in orthostatism and to test the influence of the use of external markers on the precision of this measure. DESIGN: Methodological study. METHODS: The knee frontal plane posture of 30 volunteers were analyzed by two independent examiners. The photographs were taken with different external marker arrangements. The photographs were analyzed at two moments using the Kinovea software and PhysioCode Posture (PCP) application. Reliability was analyzed using the intraclass correlation coefficient (ICC) between measures with each instrument conducted at two moments with a 7-day interval. Concurrent validity of PCP with Kinovea measure was analyzed using Pearson's correlation coefficient. Standard error measurement (SEM), minimum detectable change (MDC) and Bland Altman plots were analyzed. RESULTS: PCP demonstrated excellent intra-rater [ICC = 0.92 (95% confidence interval [CI] 0.90-0.93)] and inter-rater [ICC = 0.88 (95%CI 0.85-0.90)] reliability. Concurrent validity analysis showed excellent agreement between PCP and Kinovea software (r = 0.88). The use of markers, independent of positioning, did not influence the measurement properties of measures with both softwares. The SEM was inferior to 1.2°, and the MDC was below 2.85°. No systematic errors were observed in the Bland Altman graphs. CONCLUSIONS: The use of PCP application to measure knee posture was valid and demonstrated excellent intra- and inter-rater reliability levels. The use of external markers did not influence the measurement.

Hip passive stiffness is associated with hip kinematics during single-leg squat.

INTRODUCTION: Single-leg squat (SLS) is a test commonly used to assess lower limb function in rehabilitation. Increased hip adduction and internal rotation (IR) is associated with dynamic knee valgus, which is related to hip and knee overload. Proximal and distal factors, such as hip passive stiffness, poor hip muscle strength and excessive foot misalignment may influence hip movement. However, previous studies focus on how proximal and distal factors affected knee joint movement and did not reported the influence on hip joint. OBJECTIVE: This study investigated the association of hip external rotators (ER) strength, hip passive stiffness and shank-forefoot alignment (SFA) with hip adduction and IR during SLS. DESIGN: Cross-sectional study. METHOD: Forty-six health participants of both sexes (23.47 ± 4.29 years, 60.40 ± 11.28 kg, 1.67 ± 8.9 m) had SFA, hip ER torque, hip passive stiffness and hip kinematics assessed. Multiple linear regressions were performed to identify the factors which associated with mean and peak hip adduction and IR movement during SLS. RESULTS: Only hip passive stiffness was associated with mean (R2 = 0.164; Confidence Interval (CI) 95% = [-0.250, -0.048]; p = 0.005) and peak (R2 = 0.116; CI 95% = [-0.223, -0.210]; p = 0.019) hip IR movement. CONCLUSION: Hip passive stiffness was associated with mean and peak hip IR movement during the SLS. These results suggest that individuals with reduced hip passive stiffness may demonstrate increased hip IR movement during SLS.

The use of Horizon graphs to visualize bilateral biomechanical time-series of multiple joints.

Movement analysis provides a vast amount of data, which, frequently, are not used in the clinical decision-making process. For example, traditional gait data visualization is based on a time-based display of joint angles, but part of the information is lost when these time-series are averaged across different gait strides. Horizon graph is a data display method that increases the density of time-series data by horizontally dividing and layering multiple filled line graphs. This higher data density increases the amount of information displayed in the same graph and, consequently, enables visual data comparisons between multiple time series. Horizon graph of kinematic data allows displaying several cycles of different joints and their respective continuous symmetry ratio between sides. The aim of this work is to introduce the Horizon graph as a method to analyze kinematic gait data and help to characterize its symmetry. Examples of Horizon graph application to running is offered. Horizon graph may prove to be a useful clinical tool to visualize kinematic time-series and facilitate their clinical interpretation.•Continuous gait time series is a powerful tool for clinical analysis.•Horizon graph, higher data density graph, increases the information displayed.•Horizon graph is a clinical tool to visualize kinematic curves.

Telerehabilitation program for older adults on a waiting list for physical therapy after hospital discharge: study protocol for a pragmatic randomized trial protocol.

BACKGROUND: Delays in starting physical therapy after hospital discharge worsen deconditioning in older adults. Intervening quickly can minimize the negative effects of deconditioning. Telerehabilitation is a strategy that increases access to rehabilitation, improves clinical outcomes, and reduces costs. This paper presents the protocol for a pragmatic clinical trial that aims to determine the effectiveness and cost-effectiveness of a multi-component intervention offered by telerehabilitation for discharged older adults awaiting physical therapy for any specific medical condition. METHODS: This is a pragmatic randomized controlled clinical trial with two groups: telerehabilitation and control. Participants (n=230) will be recruited among individuals discharged from hospitals who are in the public healthcare system physical therapy waiting lists. The telerehabilitation group will receive a smartphone app with a personalized program (based on individual's functional ability) of resistance, balance, and daily activity training exercises. The intervention will be implemented at the individuals' homes. This group will be monitored weekly by phone and monthly through a face-to-face meeting until they start physical therapy. The control group will adhere to the public healthcare system's usual flow and will be monitored weekly by telephone until they start physical therapy. The primary outcome will be a physical function (Timed Up and Go and 30-s Chair Stand Test). The measurements will take place in baseline, start, and discharge of outpatient physical therapy. The economic evaluations will be performed from the perspective of society and the Brazilian public healthcare system. DISCUSSION: The study will produce evidence on the effectiveness and cost-effectiveness of multi-component telerehabilitation intervention for discharged older adult patients awaiting physical therapy, providing input that can aid the implementation of similar proposals in other patient groups. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials (ReBEC), RBR-9243v7 . Registered on 24 August 2020.

Foot pronation affects pelvic motion during the loading response phase of gait.

BACKGROUND: Increased foot pronation during walking has been associated with low back pain. This association may be due to the impact of increased pronation on pelvic motion. OBJECTIVE: To investigate the effects of increased bilateral foot pronation on pelvic kinematic in frontal and transverse planes during the loading response phase of gait. METHODS: Pelvic, hip, and foot angular positions of 20 participants were collected while they walked at fast speed wearing flat and medially inclined insoles inserted in the shoes. Pelvic motion in frontal and transverse planes was analyzed during the loading response phase. Foot eversion-inversion was analyzed during the complete stance phase to verify the insoles effectiveness in inducing increased pronation and to exclude excessive pronators. RESULTS: Inclined insoles were effective in inducing increased foot pronation. Pelvic and hip motion were altered in the increased pronation condition compared to the control condition. In the frontal plane, mean pelvic position was more inclined to the contralateral side (mean difference [MD]: 0.54°; 95%CI: 0.23, 0.86) and its range of motion (ROM) was reduced (MD: 0.50°; 95%CI: 0.20, 0.79). In the transverse plane, mean pelvic position was less rotated toward the contralateral leg (MD: 1.03°; 95%CI: 0.65, 1.60) without changes in ROM (MD: 0.04°; 95%CI: -0.17, 0.25). The hip was more internally rotated (MD: 1.37°; 95%CI: 0.76, 1.98) without changes in ROM (MD: 0.10°; 95%CI: -1.02, 1.23). CONCLUSION: Increased bilateral foot pronation changes pelvic motion during walking and should be assessed, as a contributing factor to possible pelvic and lower back disorders.

The trunk is exploited for energy transfers of maximal instep soccer kick: A power flow study.

The purpose of this study was to investigate the angular kinetic energy transfers and expenditure among the trunk (bisegmented), the pelvis and the kick limb during maximal soccer instep kicking, and to characterize kicking kinetics and kinematics. Eighteen adult male amateur soccer players (24.0 ± 4.1 years old) were assessed. Three-dimensional kinematics and ground reaction force were measured. A 6-degrees-of-freedom model was assumed, comprising the upper trunk, lower trunk, pelvis, thigh, shank and foot, and the thoraco-lumbar, lumbo-pelvic, hip, knee, and ankle joints. Angular kinematics and joint moments were computed. Power flow analysis was done by calculating the joint powers (to describe joint-to-segments energy transfers) and the proximal and distal segment powers (to describe segment-to-segment transfers). Power, kinematic and kinetic time series were presented to describe the energy flows' directions. The total mechanical energy expenditure (TMEE) at each joint was also calculated. The TMEEs pointed to substantial energy expenditure at the trunk (27% of the summed work produced by the analyzed joints). In the initial phases of kicking, the trunk generates downward energy flows from the upper to the lower trunk and from the lower trunk to the pelvis, and then to the lower limb, sequentially, which favors angular motions for ball contact. There is a formation and release of a tension arc only at the hip joint, and deceleration of the segments slightly sooner than ball contact, differently from theoretical accounts. There are energy flows, hitherto unknown, among the trunk, pelvis and kick limb, revealing mechanical strategies of kicking.

Hip passive stiffness is associated with midfoot passive stiffness.

BACKGROUND: Hip motion in the transverse plane is coupled with foot motion in the frontal plane during closed kinematic activities, such as gait. Considering that movement patterns and bone alignment might influence passive mechanical properties of joints in the long term, it is possible that hip passive stiffness and foot complex stiffness and alignment are related to each other. OBJECTIVES: To investigate whether hip passive stiffness, midfoot passive stiffness and shank-forefoot alignment are related to each other. METHOD: Thirty healthy adult individuals with a mean age of 25.4 years participated (18 women and 12 men). The Foot Torsimeter was used to measure midfoot stiffness, and hip stiffness and foot alignment were measured using clinical measures. Pearson and Spearman correlation coefficients were calculated to test the associations between each pair of variables, with α = 0.05. RESULTS: Hip stiffness was positively correlated with midfoot absolute stiffness (r = 0.41, p = 0.02), indicating that increased hip stiffness is associated with increased midfoot stiffness. There were no associations between shank-forefoot alignment and the other variables. CONCLUSIONS: In clinical settings, individuals with reduced hip passive stiffness may also have reduced midfoot passive stiffness, and vice versa. Shank-forefoot alignment is not linearly associated with hip or midfoot passive stiffness.

Do older adults present altered pelvic and trunk movement pattern during gait? A systematic review with meta-analysis and GRADE recommendations.

BACKGROUND: Cognitive, sensory, and biomechanical factors may affect gait of older adults. Among biomechanical factors, reduced pelvis and trunk range of motion (ROM) were associated with slower gait speed, shorter step length, and increased susceptibility to fall in older adults. OBJECTIVE: To systematically review the studies that compared trunk and pelvic movement during gait among adults and older adults. METHODS: Electronic search was conducted on MEDLINE, EMBASE, and Cinahl from inception until May 2020. Studies that compared trunk and/or pelvis kinematics during gait between adults and older adults were included. The following data were extracted from studies: gait speed, walking surface, and pelvis trunk ROM during gait in the three planes of motion. Meta-analyses were calculated for slow, comfortable, and fast gait speeds using random effects models. GRADE determined the strength of evidence. RESULTS: Twelve studies were included in this review. There was moderate-quality evidence that older adults have reduced pelvic rotation ROM at comfortable speed (SMD = -0.90 [-1.35, -0.45]) and high-quality evidence that older adults also have reduced pelvic rotation ROM at fast walking speed (SMD = -1.55 [-3.43, -0.33]). In addition, there was low-quality evidence that older adults have reduced trunk rotation at fast walking speed (SMD = -0.63 [-1.23, -0.03]). There were no differences for pelvic and trunk movement in the sagittal and frontal planes. CONCLUSION: There is low to high quality of evidence that older adults walk with less pelvic rotation ROM in comfortable and fast walking speeds, and less trunk rotation ROM during fast walking speed.

Effectiveness of exercises by telerehabilitation on pain, physical function and quality of life in people with physical disabilities: a systematic review of randomised controlled trials with GRADE recommendations.

OBJECTIVE: Investigate whether exercise-based telerehabilitation improves pain, physical function and quality of life in adults with physical disabilities. DESIGN: Systematic review of randomised controlled trials. DATA SOURCES: Searches were performed in AMED, MEDLINE, CINAHL, SPORTDiscus, Embase, PEDro, Cochrane Library and PsycINFO. ELIGIBILITY CRITERIA: Trials were considered if they evaluated exercise by telerehabilitation. The population included adults with physical disability. Comparisons were control and other interventions. The outcomes were pain, physical function and quality of life. Study selection, data extraction and analysis followed the protocol registered in PROSPERO (CRD42019122824). GRADE determined the strength of evidence. RESULTS: Forty-eight trials were included in the quantitative analysis. When compared with other interventions, there was high-quality evidence that telerehabilitation was not different to other interventions for pain (95% CI: -0.4 to 0.1), physical function (95% CI: -0.2 to 0.2) and quality of life (95% CI: -0.1 to 0.5) at long-term. There was moderate-quality evidence that telerehabilitation was not different to other interventions for physical function (95% CI: -0.1 to 0.5) and quality of life (95% CI: -0.2 to 0.5) at short-term. However, due to the low-quality evidence and the small number of trials comparing exercise protocols offered by telerehabilitation with control groups, it is still not possible to state the efficacy of telerehabilitation on pain, function and quality of life at short-term and long-term. CONCLUSIONS: Exercise by telerehabilitation may be an alternative to treat pain, physical function and quality of life in adults with physical disabilities when compared with other intervention.

Current clinical practice and return-to-sport criteria after anterior cruciate ligament reconstruction: a survey of Brazilian physical therapists.

BACKGROUND: Adherence to the use of recommended measures/criteria for return to sport clearance after anterior cruciate ligament reconstruction is crucial for successful rehabilitation. OBJECTIVES: The purpose of this study was to describe the current clinical practice of Brazilian physical therapists that treat patients after anterior cruciate ligament reconstruction, including the measures/criteria used to support the decision-making process regarding return to sport. The secondary aim was to investigate factors associated with the use of the most recommended measures/criteria for return to sport. METHODS: An electronic survey questionnaire was sent to Brazilian physical therapists. The survey consisted of questions about demographics and professional and clinical practice data related to anterior cruciate ligament reconstruction postoperative rehabilitation and return to sport criteria. Descriptive statistics and chi-square tests were used for analyses. RESULTS: A sample of 439 professionals participated in the survey. Only 6.4% of the physical therapists use the most recommended measures/criteria for return to sport after anterior cruciate ligament reconstruction. Professional certification in Sports Physical Therapy was the only factor associated with the use of these recommended measures/criteria (p=0.02). The measures most used for return to sport clearance were related to physical factors (65.3% to 75.1%), such as range of motion and muscle strength. A small number of professionals use questionnaires to assess functional (16.6%) and psychological (19.1%) aspects of their patients to support the decision-making process. CONCLUSION: In their clinical practice, most Brazilian physical therapists do not use the recommended measures/criteria for return to sport after anterior cruciate ligament reconstruction.

Prediction equation of hip external rotators maximum torque in healthy adults and older adults using the measure of hip extensors maximum torque.

BACKGROUND: The use of predictive equation of muscular torque can reduce physical effort and time spent during evaluation. OBJECTIVES: To establish, validate, and test the accuracy of a prediction equation to estimate the hip external rotators (HER) torque in adults and older adults by means of hip extensors (HEX) torque measurement. METHODS: Eighty-three healthy adults (development set) were assessed to test the association of HEX and HER torques and to establish the prediction equation. A separate 36 adults and 15 older adults (validation sets) were assessed to test the ability of the equation to estimate HER torque. Hip isometric strength was assessed by a handheld dynamometer. RESULTS: Simple linear regression analysis revealed that HEX torque was associated with HER torque (r=0.80; p<0.0001), resulting in the following prediction equation: HERtorque=-0.02+(0.58 * HEXtorque). Paired t-test revealed no difference between directly measured and predicted values of HER torque in adults (mean difference=0.02; 95% CI=-0.115, 0.072) and older adults (mean difference=0.05; 95% CI=-0.02, 0.12). CONCLUSION: The HEX and HER torques were strongly correlated. The prediction equation was valid, accurate, and can be used to estimate HER muscle strength in healthy adults and older adults, requiring only the direct measurement of HEX torque.

Prevalence and incidence of injuries in para athletes: a systematic review with meta-analysis and GRADE recommendations.

OBJECTIVE: To investigate prevalence, incidence and profile of musculoskeletal injuries in para athletes. DESIGN: Systematic review. DATA SOURCES: Searches were conducted in MEDLINE, EMBASE, AMED, SPORTSDiscus, CINAHL and hand searching. ELIGIBILITY CRITERIA: Studies were considered if they reported prevalence or incidence of musculoskeletal injuries in para athletes. Study selection, data extraction and analysis followed the protocol. Meta-analyses were conducted to estimate the prevalence and incidence rate among studies and subgroup analyses investigated whether methodological quality and sample size of the studies influenced on the estimated injury prevalence and incidence. The Grading of Recommendations Assessment, Development and Evaluation system determined the strength of evidence. RESULTS: Forty-two studies were included. The prevalence of musculoskeletal injuries was 40.8% (95% CI 32.5% to 49.8%). Because of imprecision, indirectness and inconsistency, the strength of evidence was very low quality. The incidence of musculoskeletal injuries was 14.3 injuries per 1000 athlete-days (95% CI 11.9 to 16.8). The strength of evidence was low quality because of imprecision and indirectness. The subgroup analyses revealed that the sample size influenced on estimated injury prevalence and methodological quality influenced on estimated incidence. Injuries were more prevalent in the shoulder, for non-ambulant para athletes, and in the lower limbs, for ambulant para athletes. SUMMARY/CONCLUSION: Para athletes show high prevalence and incidence of musculoskeletal injuries. Current very low-quality and low-quality evidence suggests that future high-quality studies with systematic data collection, larger sample size and specificities of para athletes are likely to change estimates of injury prevalence and incidence in para athletes. PROSPERO REGISTRATION NUMBER: CRD42020147982.

Reliability and sensitivity of an instrument for measuring the midfoot passive mechanical properties.

To assess the test - retest reliability and sensitivity of an instrument developed to measure the passive mechanical properties of the midfoot joint complex (MFJC), nine female and three male healthy young adults were evaluated in two different days by two experienced examiners. After proper participant positioning on the instrument, the left forefoot was passively moved from eversion (20°) to inversion (45°) at 2°/s, while the rearfoot and shank were kept immobile. From the instrument's sensing units (torque meter and potentiometer at 100 Hz), passive torque and angle data were registered. Passive stiffness was calculated as the instantaneous slope of the torque vs. angle curve. Therefore, the variables analyzed were resting angle, passive torques and stiffnesses during inversion and eversion through the intraclass correlation coefficient (ICC3,3), standard error of measurement (SEM) and minimal detectable change (MDC95). For the resting angle, ICC3,3 ranged from 0.85 to 0.91, SEM ranged from 1.54° to 1.95° and MDC95 ranged from 4.26° to 5.41°. For the torques, ICC3,3 ranged from 0.85 to 0.97, SEM ranged from 0.09Nm to 0.42Nm and MDC95 ranged from 0.26Nm to 1.16Nm. Finally, for the stiffnesses, ICC3,3 ranged from 0.79 to 0.98, SEM ranged from 0.01Nm/° to 0.04Nm/° and MDC95 ranged from 0.01Nm/° to 0.10 Nm/°. It can be concluded that most of the measurements presented good to excellent reliability with low measurement error. Hence, clinicians and researchers may benefit from the reliable and stable measures provided by the Foot Torsimeter when assessing patients and planning interventions.

Lower limb kinematics and hip extensors strengths are associated with performance of runners at high risk of injury during the modified Star Excursion Balance Test.

BACKGROUND: Reduced trunk and lower limb movement and hip and trunk muscles weakness may compromise the athletes' performance on the modified Star Excursion Balance Test (mSEBT). OBJECTIVE: To investigate the relationship of trunk and lower limb kinematics and strength with the performance on the mSEBT of runners at high risk of injury. METHODS: Thirty-nine runners performed the mSEBT with the dominant limb as the support limb. An Inertial System was used to capture the trunk, hip, knee and ankle movement during the mSEBT. A handheld dynamometer was used to measure the strength of trunk extensors and lateral flexors muscles, and hip extensors, lateral rotators and abductors of the support limb. Multiple regressions were used to investigate if trunk and lower limbs kinematics and trunk and hip muscles strength are associated with performance during the mSEBT. RESULTS: Reduced hip flexion and greater knee flexion range of motion (ROM) were associated with anterior reach in the mSEBT (r2=0.45; p<.001), greater hip flexion ROM was associated with posteromedial reach (r2=0.15; p=.012) and greater knee flexion ROM was associated with posterolateral reach (r2=0.23; p<.001). Hip extensor strength was associated with posteromedial (r2=0.14; p=.017), posterolateral (r2=0.10; p=.038) and composite reaches (r2=0.16; p=.009). CONCLUSION: Hip and knee kinematics in the sagittal plane explained 15-45% of the runners' performance on the mSEBT and hip extensor strength explained 10-16% of the mSEBT performance. These findings provide useful information on the contribution of joints kinematics and strength when evaluating dynamic postural control in runners at high risk of injury.

Influence of reducing anterior pelvic tilt on shoulder posture and the electromyographic activity of scapular upward rotators.

BACKGROUND: Modifications of posture in a segment may influence the posture of adjacent and nonadjacent segments and muscular activity. The spine-shoulder and spine-pelvis relationships suggest that the pelvis may influence shoulder posture. OBJECTIVE: To investigate the effect of the active reduction of the anterior pelvic tilt on shoulder and trunk posture during static standing posture and on the electromyographic activity of the scapular upward rotators during elevation and lowering of the arm. METHODS: Thirty-one young adults were assessed in a relaxed standing position and a standing position with 30% active reduction of the anterior pelvic tilt. The pelvic tilt, trunk posture, and forward shoulder posture during the static standing posture and the electromyographic activity during elevation and lowering of the arm were assessed. RESULTS: Paired t-tests indicated that the active reduction of the anterior pelvic tilt reduced the trunk extension (MD=1.09; 95%CI=-2.79 to -1.03). There were no effects on the forward shoulder posture (MD=0.09; 95%CI=-0.92 to 1.09). Repeated measures of analyses of variance indicated an increase in lower trapezius electromyographic activity (MD=3.6; 95%CI=1.28 to 5.92). There was a greater reduction in upper trapezius activity after pelvic tilt reduction during arm elevation (MD=1.52%; 95%CI=-2.79 to -0.25) compared to that during the lowering phase. There were no effects of pelvic tilt reduction on the electromyographic activity of the serratus anterior (MD=3.26; 95%CI=-3.36 to 9.87). CONCLUSION: The influence of pelvic posture on the trunk posture and lower trapezius activation should be considered when assessing or planning exercise for individuals with shoulder or trunk conditions.