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Background While altered foot arch characteristics (high or low) are frequently assumed to influence lower limb biomechanics and are suspected to be a contributing factor for injuries, the association between arch characteristics and lower limb running biomechanics in children is unclear. Research question Therefore, the aim of this study was to investigate the relationship between a dynamically measured arch index and running biomechanics in healthy children. Methods One hundred and one children aged 10–14 years were included in this study and underwent a biomechanical investigation. Plantar distribution (Novel, Emed) was used to determine the dynamic arch index and 3D motion capture (Vicon) to measure running biomechanics. Linear mixed models were established to determine the association between dynamic arch index and foot strike patterns, running kinematics, kinetics and temporal-spatial outcomes. Results No association was found between dynamic arch index and rate of rearfoot strikes (p = 0.072). Of all secondary outcomes, only the foot progression angle was associated with the dynamic arch index (p = 0.032) with greater external rotation in lower arched children. Significance Overall, we found only few associations between arch characteristics and running biomechanics in children. However, altered foot arch characteristics are of clinical interest. Future studies should focus on detailed foot biomechanics and include clinically diagnosed high and low arched children.

Effects of early and permanent footwear use are not well understood. The aim of this study was to investigate the effects of habituation to footwear on foot strike patterns of children and adolescents. Healthy habitually barefoot and shod participants (aged 6–18 years) from South Africa (n=288) and Germany (n=390) performed multiple 20-m jogging and running trials with and without shoes. Each foot strike was captured using a high-speed camera to determine a rearfoot or non-rearfoot strike. The probability of a rearfoot strike in both cohorts and each age was analyzed by using a mixed-effects logistic regression adjusted for possible confounders. Habitually barefoot children showed a higher probability of using rearfoot strikes than habitually shod children (p

The development of the human foot is crucial for motor learning in children and adolescents as it ensures the basic requirements for bipedal locomotion and stable standing. Although there is an ongoing debate of the advantages and disadvantages of early and permanent footwear use, the influence of regular barefootness on foot characteristics in different stages of child development has not been extensively evaluated. A multicenter epidemiological study was conducted to compare the foot morphology between habitually barefoot children and adolescents (N = 810) to age-, sex- and ethnicity-matched counterparts that are used to wearing shoes. While controlling for confounders, we found that habitual footwear use has significant effects on foot-related outcomes in all age groups, such as a reduction in foot arch and hallux angles. The results indicate an impact of habitual footwear use on the development of the feet of children and adolescents. Therefore, growing up barefoot or shod may play an important role for childhood foot development, implying long-term consequences for motor learning and health later in life.

Gait variability is frequently used to evaluate the sensorimotor system and elderly fallers compared to non-fallers exhibit an altered variability in gait parameters during unchanged conditions. While gait variability is often interpreted as movement error, it is also necessary to change the gait pattern in order to react to internal and external perturbations. This phenomenon has been described as functional variability and ensures the stability of gait motor control. The aim of the current study is to explore the functional variability in relation to the different phases of the gait cycle (phase-dependent gait variability). Kinematics of the foot, shank and thigh were registered with inertial sensors (MTw2, Xsens Technologies B.V) in 25 older participants (70±6years) during normal overground walking. Phase-dependent variability was defined as the standard deviation of the Euclidean norm of the angular velocity data. To assess differences with respect to the variability of different body segments (foot, shank, and thigh), the statistical parametric mapping method was applied. In normal walking, the variability of the time-continuous foot kinematics during parts of the swing phase was higher compared to the shank (9-14% of swing phase, p

This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. Diminishing proprioception caused by aging effects is associated with a higher risk to fall. However, existing measurement systems of proprioception are often expensive, time-consuming, or insufficient regarding reliability evaluation. Inertial sensor-based systems could address these issues. Consequently, this study sought to develop and evaluate an inertial sensor-based joint position sense test. Thereto, intra-session and inter-day test-retest reliability were investigated in a cross-over design. Twenty healthy younger (age: 22 ± 3 years) and 20 healthy older adults (age: 65 ± 5 years) participated in the study. We calculated the mean of the absolute error, the signed error, and the standard deviation of the signed error. Test-retest reliability was quantified by using the intraclass correlation coefficient as well as the bias and limits of agreement. To evaluate the possibility of capturing aging effects, and correspondingly a validation of the system, we calculated Cohen's d. For the intra-session reliability, fair to good agreements were achieved for the absolute and relative error in all target ranges. Compared to younger adults, we registered a declined joint position sense in older adults with high effects observed for the absolute error in a target range of 15–25 and 35–45° as well as for the variable error in the target ranges of 35–45 and 55–65°. We suggest that inertial sensor-based joint position sense tests are reliable and capable to measure aging effects on proprioception, and are therefore a low-cost and mobile alternative to existing methods.

During everyday locomotion, we cope with various internal or external perturbations (e.g. uneven surface). Uncertainty exists on how unpredictable external perturbations increase noise within the motor system and if they are compensated by employing covariation of the limb joints or rather due to decreased sensitivity of an altered posture.Do continuous stochastic perturbations affect the structure of gait variability in young and healthy adults?In a cross-over study, gait kinematics of 21 healthy young sports students were registered during treadmill walking with and without continuous stochastic perturbations. Using the TNC method, the following aspects were analyzed: (a) the sensitivity of body posture to perturbations ('tolerance') decreasing gait variability, (b) the unstructured motor 'noise' increasing gait variability and (c) the amount of 'covariation' of the limb joints.Compared to normal walking, gait variability was significantly increased (p .001) during walking with perturbations. The negative effect of noise was partly compensated by improved 'covariation' of leg joints (p .001). The aspect 'tolerance' had a small effect on increasing gait variability during stance phase (p .001) and decreasing gait variability during swing phase (p .001).Increased motor noise due to external perturbations is partly compensated by improved covariation of the limb joints. However, the effect of an altered posture slightly affects gait variability. Further studies should focus on different populations (e.g. older participants) to see if they use the same mechanism (improved covariation) to compensate for stochastic perturbations.

Context: In some patients, ankle sprains lead to chronic symptoms like pain or muscular weakness called chronic ankle instability (CAI). External ankle supports have shown to be effective in preventing sprains and reducing recurrence, but the underlying mechanisms are unclear. As sensorimotor variables are associated with injury incidence, an influence of external ankle support on landing performance and balance seems plausible. Objective: To analyze the effects of an elastic ankle support on jump landing performance and static and dynamic balance in patients with CAI and healthy controls. Design: Crossover study. Setting: Functional tests in a laboratory setting. Patients or Other Participants: Twenty healthy students and 20 patients with CAI were included for study participation based on their scores in ankle stability and function questionnaires. Intervention: Healthy and CAI participants performed each test with and without an elastic ankle support. Main Outcome Measures: (1) Jump landing performance was measured with the Landing Error Scoring System, (2) static balance was assessed with the Balance Error Scoring System, and (3) dynamic balance was assessed using the Y Balance Test. Linear mixed models were used to analyze the effects of the elastic ankle support on sensorimotor parameters. Results: Healthy controls performed significantly better in the Landing Error Scoring System (P = .01) and Y Balance Test anterior direction (P = .01). No significant effects of elastic ankle support on Landing Error Scoring System, Balance Error Scoring System, or Y Balance Test performance were observed in the CAI or control group. There were no significant group-by-ankle support interactions. Conclusions: In the current study, the acute use of elastic ankle support was ineffective for enhancing jump landing performance, and static and dynamic balance. Further research is needed to identify the underlying mechanisms of the preventive effects of elastic ankle support.

Dual-task costs of gait (variability) parameters are frequently used to probe the grade of automaticity of walking. However, recent studies reported contradicting dual-task costs for different gait variability measures within the same cohorts. The effects of a dual-task on the gait pattern are, thus, not fully understood. The aim of the current study was to analyze the different gait variability components (‘Tolerance’, ‘Noise’, and ‘Covariation’) during dual-task walking compared to single-task walking. In an experimental study, 21 young and healthy adults (11 males, 10 females, age: 24 ± 3 years) were included. The participants completed three experimental conditions: (a) single-task walking, (b) dual-task walking (serial-seven subtractions), and (c) cognitive single task in sitting position. To analyze different gait variability components, we applied a method which distinguishes the three components: ‘Tolerance’, ‘Noise’, and ‘Covariation’ (TNC). To test for differences, we used the statistical parametric mapping method. Compared to single-task walking, the results depict lower gait variability of the result parameters during the dual-task condition at 0–15% (p = 0.010) and 94–100% (p = 0.040) of the stance phase and 0–63% (p

Background Medial longitudinal arch characteristics are thought to be a contributing factor to lower limb running injuries. Running biomechanics associated with different foot types have been proposed as one of the potential underlying mechanisms. However, no systematic review has investigated this relationship. Research question The aim of this study was to conduct a systematic literature search and synthesize the evidence about the relationship between foot posture and running biomechanics. Methods For this systematic review and meta-analysis different electronic databases (Pubmed, Web of Science, Cochrane, SportDiscus) were searched to identify studies investigating the relationship between medial longitudinal arch characteristics and running biomechanics. After identification of relevant articles, two independent researchers determined the risk of bias of included studies. For homogenous outcomes, data pooling and meta-analysis (random effects model) was performed, and levels of evidence determined. Results Of the 4088 studies initially identified, a total of 25 studies were included in the qualitative review and seven in the quantitative analysis. Most studies had moderate and three studies a low risk of bias. Moderate evidence was found for a relationship between foot posture and subtalar joint kinematics (small pooled effects: −0.59; 95%CI −1.14 to − 0.003) and leg stiffness (small pooled effect: 0.59; 95%CI 0.18 to 0.99). Limited or very limited evidence was found for a relationship with forefoot kinematics, tibial/leg rotation, tibial acceleration/shock, plantar pressure distribution, plantar fascia tension and ankle kinetics as well as an interaction of foot type and footwear regarding tibial rotation. Significance While there is evidence for an association between foot posture and subtalar joint kinematics and leg stiffness, no clear relationship was found for other biomechanical outcomes. Since a comprehensive meta-analysis was limited by the heterogeneity of included studies future research would benefit from consensus in foot assessment and more homogenous study designs.

Postural control requires the sensory integration of visual, vestibular, and proprioceptive signals. In the absence of vision, either by blindfolding or in blind individuals, balance performance is typically poorer than with sight. Previous research has suggested that despite showing compensatory vestibular and proprioceptive processing during upright standing, balance performance in blind individuals is overall lower than in sighted controls with eyes open. The present study tested whether balance training, which places demands on vestibular and proprioceptive self-motion perception, improves balance performance in blind adults, and whether we find similar structural correlates in cortical and subcortical brain areas as have been reported in sighted individuals. Fourteen congenitally or late blind adults were randomly assigned to either a balance or a relaxation group and exercised twice a week for 12 weeks. Assessments prior to and after training included balance tests and the acquisition of T1-weighted MRI images. The blind balance group significantly improved in dynamic, static, and functional balance performance compared to the blind relaxation group. The balance performance improvement did not differ from that of age- and gender matched sighted adults after balance training. Cortical thickness increased in the left parahippocampus and decreased in the inferior insula bilaterally in the blind balance group compared to the blind relaxation group. Thickness decreases in the insula were related to improved static and functional balance. Gray matter volume was reduced in the left hippocampus proper and increased in the right subiculum in the blind balance group. The present data suggest that impaired balance performance in blind adults can be significantly improved by a training inducing plasticity in brain regions associated with vestibular and proprioceptive self-motion processing.

Physical exercise has been shown to improve cognitive functions. However, it is still unknown which type of exercise affects cognition. In the present study, we tested the hypothesis that a demanding balance training program improves memory and spatial cognition. Forty healthy participants aged 19-65 years were randomly assigned to either a balance or relaxation training intervention. Each group exercised twice a week for a total of 12 weeks. Pre- and posttests assessed balance performance, cardiorespiratory fitness, memory, spatial cognition, and executive functions. Only the balance group significantly increased in balance performance from pre- to posttest, while cardiorespiratory fitness remained unchanged in both groups. Moreover, the balance group significantly improved in memory and spatial cognition. Effects on executive functions were not observed. These results suggest that balance training is capable of improving particularly memory and spatial cognition. Therefore, an increase in cardiorespiratory fitness does not seem to be necessary to induce beneficial effects of physical exercise on cognition. It might be speculated that stimulating the vestibular system during balance training induces changes of the hippocampus and parietal cortex possibly via direct pathways between the vestibular system and these brain regions.

Biological maturation is associated with physiological changes which in turn affect motor performance. No study has assessed the association between growing up habitually shod versus habitually barefoot and motor performance in the context of maturation, so this approach is unique. The purpose of this study was to examine the influence of biological maturity on motor performance dependent on the participants' footwear habits. Sixty-five German habitually shod (mean age 13.28 ± 0.83 years) and fifty-five South African habitually barefoot (mean age 13.38 ± 0.87 years) participants were included. Dynamic postural control was determined via backward balancing, explosive strength by standing long jump and sprinting performance based on a 20-m sprinting test. All tests were performed barefoot and shod. Biological maturation was calculated by using the maturity offset value. Linear mixed models were used to analyse interactions between the maturity offset value, footwear habits and motor performance. Throughout maturation, there was a significant difference between habitually barefoot and habitually shod balance performance (P = 0.001). Maturation led to balance improvements in habitually barefoot adolescents, but not in habitually shod adolescents. No such differences could be observed for standing long jump and 20-m sprint performance. Maturity offset was a significant predictor for jumping and sprinting performances (P 0.001), independent of being habitually barefoot or habitually shod. Better performances could be observed in more mature subjects. Biological maturation seems to be a relevant predictor for motor performance characteristics for the jumping and sprinting performance in adolescents.

The Matthiass test serves to identify postural insufficiencies by evaluating the sagittal posture but this subjective assessment may be responsible for different reports on the prevalence of postural insufficiencies in children. Previously, rasterstereography was used to objectify this clinical test. Until now, the coupling of the Matthiass test with rasterstereography has not yet been applied to children and the reliability is unknown; therefore, the objective of our study was to provide interday and interrater reliability of rasterstereographic measurements during dynamic (modified Matthiass test) and static trials (only interday) in healthy children. Trunk inclination, kyphotic, and lordotic angles were measured using rasterstereography during static and dynamic trials (modified Matthiass test: 90° shoulder flexion, hand-held load, 5% of body weight). Intraclass correlation coefficients (ICC) were calculated using a two-way mixed model (absolute agreement, average measure). In this study 21 healthy children were assessed (age range 10–12 years). Dynamic rasterstereographic measurements showed fair to good interday and interrater reliability (ICC 0.46–0.70) and static measurements good to excellent interday reliability (ICC 0.63–0.91). Dynamic rasterstereography during the modified Matthiass test furnishes reliable data serving to objectify spinal changes of healthy children and detect postural insufficiencies. Additional efforts are needed to investigate how the early detection of postural insufficiencies can help to prevent back pain in children, adolescents and adults.

Although barefoot balancing has shown to be more challenging compared to shod balancing, it is still unclear whether this may also influence the balance learning effects. The purpose of this study was to explore the impact of barefoot and shod exercising on learning of a dynamic balance task. Sixty healthy and physically active adults (mean age 25.3 ± 3.4 years) were randomly allocated into one of three groups (barefoot, shod and controls). The barefoot and shod intervention groups exercised once weekly over 7 weeks on a stability platform with an unstable surface. Each training session included 15 trials over 30 s. Before and after the intervention period, all participants completed two balance tests (stability platform and Balance Error Scoring System = BESS) under barefoot and shod conditions. Group effects in stability gains (pre to post-test differences) were analysed using ANOVA. Development of balance learning curves during the intervention period was analysed using a mixed effects model. Balance times improved in both intervention groups (p

The aim of this pilot study was to investigate whether the clinical Matthiass test can be objectified by means of dynamic rasterstereography in children. We aimed at discriminating between postural weak and strong children. Dynamic rasterstereography was used to capture sagittal spinal posture changes during the modified Matthiass test (mMT). Primary outcomes were spinal posture changes (trunk inclination, kyphotic and lordotic angles) during the test. Two-step cluster analysis was run jointly on the three primary outcomes. Data of 101 healthy children (10-14 years, 46% girls) were assessed. Cluster analysis identified two groups of participants with significantly different postural performance levels during the mMT (low vs. high performers). Low performers showed a higher increase in backward lean, as well as kyphosis and lordosis (4°-5°, respectively) when compared to high performers. The two performance groups were age-, BMI-, and activity-matched.Conclusion: This pilot study established preliminary normative data on spinal posture changes during the Matthiass test (high performers) and provided corresponding cutoff values for postural weakness (low performers). These results could provide a basis for future longitudinal and interventional studies targeting long-term consequences of childhood postural weakness and the prevention of back pain. What is Known: • The prevalence of postural insufficiencies in children is high. • No consensus exists about the postural assessment in children. • A common clinical test to identify postural insufficiency is the Matthiass test yet criticized for its subjective assessment. What is New: • This pilot study objectified the modified Matthiass test by rasterstereography and statistically identified two groups of healthy children with different postural performance levels. • It established preliminary normative data on spinal posture changes and provided corresponding cutoff values for postural weakness.

Dual task (DT) training is becoming prominent in fall prevention. However, DT training should include task-managing strategies like task switching or task prioritization to be beneficial to improve gait performance under DT conditions. The aim of this pilot study was to evaluate the effect of a task managing training on gait stability.A DT training (12 sessions; 60 min each; 12 weeks) was compared to a non-training control group within a RCT (38 independent living participants; 72.7 ± 4.7 years). Single Task (ST) and DT walking (visual verbal Stroop task) were measured on a treadmill (FDM-T, 3.5 km/h, 100 HZ). Gait parameters like step length, step width, gait line, maximum forces and gait variability were compared.The training group improved their gait performance under ST and DT conditions as revealed by significant group × time interaction effects.The training successfully improved gait performance and therefore might be a promising approach to prevent falls. Additional fall prevention studies should focus on motor-cognitive performance and reinforce outcomes of task managing strategies.

Auditory information affects sensorimotor control of gait. Noise or active noise cancelling alters the perception of movement related sounds and, probably, gait stability. The aim of the current study was to evaluate the effects of noise cancelling on gait stability. Twenty-five healthy older subjects (70 ± 6 years) were included into a randomized cross-over study. Gait stability (largest Lyapunov exponent) in normal overground walking was determined for the following hearing conditions: no manipulation and active noise cancelling. To assess differences between the two hearing conditions (no manipulation vs. active noise cancelling), Student’s repeated measures t-test was used. The results indicate an improvement of gait stability when using active noise cancelling compared to normal hearing. In conclusion, our results indicate that auditory information might not be needed for a stable gait in elderly.

Physical exercise has been shown to improve cognitive functions. However, it is still unknown which type of exercise affects cognition. In the present study, we tested the hypothesis that a demanding balance training program improves memory and spatial cognition. Forty healthy participants aged 19–65 years were randomly assigned to either a balance or relaxation training intervention. Each group exercised twice a week for a total of 12 weeks. Pre- and posttests assessed balance performance, cardiorespiratory fitness, memory, spatial cognition, and executive functions. Only the balance group significantly increased in balance performance from pre- to posttest, while cardiorespiratory fitness remained unchanged in both groups. Moreover, the balance group significantly improved in memory and spatial cognition. Effects on executive functions were not observed. These results suggest that balance training is capable of improving particularly memory and spatial cognition. Therefore, an increase in cardiorespiratory fitness does not seem to be necessary to induce beneficial effects of physical exercise on cognition. It might be speculated that stimulating the vestibular system during balance training induces changes of the hippocampus and parietal cortex possibly via direct pathways between the vestibular system and these brain regions.

While recent research debates the topic of natural running in adolescents and adults, little is known about the influence of footwear on running patterns in children. The purpose of this study was to compare shod and barefoot running gait biomechanics in preadolescent children. Kinematic and ground reaction force data of 36 normally developed children aged 6-9 years were collected during running on an instrumented treadmill. Running conditions were randomized for each child in order to compare barefoot running with two different shod conditions: a cushioned and a minimalistic running shoe. Primary outcome was the ankle angle at foot strike. Secondary outcomes were knee angle, maximum and impact ground reaction forces, presence of rear-foot strike, step width, step length and cadence. Ankle angle at foot strike differed with statistical significance (p < 0.001) between conditions. Running barefoot reduced the ankle angle at foot strike by 5.97° [95% CI, 4.19; 7.75] for 8 kmh(-1) and 6.18° [95% CI, 4.38; 7.97] for 10 kmh(-1) compared to the cushioned shoe condition. Compared to the minimalistic shoe condition, running barefoot reduced the angle by 1.94° [95% CI, 0.19°; 3.69°] for 8 kmh(-1) and 1.38° [95% CI, -3.14°; 0.39°] for 10 kmh(-1). Additionally, using footwear significantly increased maximum and impact ground reaction forces, step length, step width and rate of rear-foot strike. In conclusion, preadolescent running biomechanics are influenced by footwear, especially by cushioned running shoes. Health professionals and parents should keep this in mind when considering footwear for children.

Background Sensorimotor control is permanently impaired following functional ankle instability and temporarily decreased following fatigue. Little is known on potential interactions between both conditions. The purpose was to investigate the effect of fatiguing exercise on sensorimotor control in athletes with and without (coper, controls) functional ankle instability. Methods 19 individuals with functional ankle instability, 19 ankle sprain copers, and 19 non-injured controls participated in this cohort study. Maximum reach distance in the star excursion balance test, unilateral jump landing stabilization time, center of pressure sway velocity in single-leg-stance, and passive ankle joint position sense were assessed before and immediately after fatiguing treadmill running. A three factorial linear mixed model was specified for each outcome to evaluate the effects of group, exhausting exercise (fatigue) and their interactions (group by fatigue). Effect sizes were calculated as Cohen's d. Findings Maximum reach distance in the star excursion balance test, jump stabilization time and sway velocity, but not joint position sense, were negatively affected by fatigue in all groups. Effect sizes were moderate, ranging from 0.27 to 0.68. No significant group by fatigue interactions were found except for one measure. Copers showed significantly larger prefatigue to postfatigue reductions in anterior reach direction ( P ≤ 0.001; d = − 0.55) compared to the ankle instability ( P = 0.007) and control group ( P = 0.052). Interpretation Fatiguing exercise negatively affected postural control but not proprioception. Ankle status did not appear to have an effect on fatigue-induced sensorimotor control impairments.

Context: Sensorimotor control is impaired after ankle injury and in fatigued conditions. However, little is known about fatigue-induced alterations of postural control in athletes who have experienced an ankle sprain in the past. Objective: To investigate the effect of fatiguing exercise on static and dynamic balance abilities in athletes who have successfully returned to preinjury levels of sport activity after an ankle sprain. Design: Cohort study. Setting: University sport science research laboratory. Patients or Other Participants: 30 active athletes, 14 with a previous severe ankle sprain (return to sport activity 6–36 months before study entry; no residual symptoms or subjective instability) and 16 uninjured controls. Intervention(s): Fatiguing treadmill running in 2 experimental sessions to assess dependent measures. Main Outcome Measure(s): Center-of-pressure sway velocity in single-legged stance and time to stabilization (TTS) after a unilateral jump-landing task (session 1) and maximum reach distance in the Star Excursion Balance Test (SEBT) (session 2) were assessed before and immediately after a fatiguing treadmill exercise. A 2-factorial linear mixed model was specified for each of the main outcomes, and effect sizes (ESs) were calculated as Cohen d. Results: In the unfatigued condition, between-groups differences existed only for the anterior-posterior TTS (P = .05, ES = 0.39). Group-by-fatigue interactions were found for mean SEBT (P = .03, ES = 0.43) and anterior-posterior TTS (P = .02, ES = 0.48). Prefatigue versus postfatigue SEBT and TTS differences were greater in previously injured athletes, whereas static sway velocity increased similarly in both groups. Conclusions: Fatiguing running significantly affected static and dynamic postural control in participants with a history of ankle sprain. Fatigue-induced alterations of dynamic postural control were greater in athletes with a previous ankle sprain. Thus, even after successful return to competition, ongoing deficits in sensorimotor control may contribute to the enhanced ankle reinjury risk.

In der Rehabilitation von Patienten nach Knie- oder Huft-Totalendoprothese (TEP) nimmt die Bewegungstherapie eine dominierende Rolle ein. Fur deren individuell optimale Dosierung liegen allerdings kaum wissenschaftliche Nachweise vor. Zur weiteren Verbesserung der Qualitat der Bewegungstherapie in der Rehabilitation nach Knie- oder Huft-TEP bedarf es, auch angesichts des zunehmenden Kostendrucks im Gesundheitswesen und hoher bzw. voraussichtlich noch weiter steigender Fallzahlen, zukunftig der vermehrten Schaffung belastbarer Aussagen uber Dosis-Wirkungs-Beziehungen, z. B. durch die Entwicklung und Evaluierung innovativer bewegungstherapeutischer Interventionskonzepte. Im vorliegenden Artikel werden entsprechende Hintergrunde, der aktuelle Stand der Wissenschaft und der therapeutischen Praxis sowie Ansatzpunkte fur eine adaquate Weiterentwicklung der Bewegungstherapie aufgezeigt.

Background Barefoot locomotion has evoked an increasing scientific interest with a controversial debate about benefits and limitations of barefoot and simulated barefoot walking and running. While most current knowledge comes from cross sectional laboratory studies, the evolutionary perspective suggests the importance of investigating the long-term effects. Observing habitually barefoot populations could fill the current gap of missing high quality longitudinal studies. Therefore, the study described in this design paper aims to investigate the effects of being habitually barefoot on foot mechanics and motor performance of children and adolescents. Methods This study has a cross-sectional, binational design and is part of the “Barefoot Locomotion for Individual Foot- and health Enhancement (Barefoot LIFE)” project. Two large cohorts (n(total) = 520) of healthy children and adolescents between 6 and 18 years of age will be included respectively in Germany and South Africa. A barefoot questionnaire will be used to determine habitually barefoot individuals. The testing will be school-based and include foot mechanical (static arch height index, dynamic arch index, foot pliability) and motor performance (coordination, speed, leg power) outcomes. Gender, BMI and level of physical activity will be considered for confounding. Discussion The strength of this study is the comparison of two large cohorts with different footwear habits to determine long-term effects of being habitually barefoot on foot mechanics and motor performance. Electronic supplementary material The online version of this article (doi:10.1186/s13047-016-0166-1) contains supplementary material, which is available to authorized users.

Zech A, Steib S, Freiberger E, Pfeifer K. Functional muscle power testing in young, middle-aged, and community-dwelling nonfrail and prefrail older adults. Objective To evaluate the stair climb (SC) and sit-to-stand (STS) transfer test for functional power assessment in young, middle-aged, and community-dwelling nonfrail and prefrail older adults. Design Cross-sectional study. Setting Sport science institute providing health-related exercise programs for older people. Participants Participants (N=60; age, 22–81y) were divided into groups of young (n=15; 20–30y), middle-aged (n=16; 40–60y), nonfrail older (n=16; >65y), and prefrail older adults (n=13; >65y). Interventions Not applicable. Main Outcome Measures SC and STS transfer power were measured on 2 separate occasions. Results Age and height correlated positively ( P R 2 ) of the variance in SC power and 31.3% ( R 2 ) of the variance in STS transfer power can be attributed to age and height. Significant age-related subgroup differences were found for SC power ( P =.001). Nonfrail and prefrail older adults differed significantly in both power measures ( P Conclusions The findings indicate that SC and STS transfer power are sensitive enough to distinguish between nonfrailty and prefrailty. This suggests that both tests are relevant clinical measures in older people.

ZECH, A., M. HUBSCHER, L. VOGT, W. BANZER, F. HANSEL, and K. PFEIFER. Neuromuscular Training for Rehabilitation of SportsInjuries: A SystematicReview.Med. Sci. Sports Exerc., Vol.41, No. 10, pp.1831-1841, 2009.Purpose: Although proprioceptive and neuromuscular exercises are considered to be part and parcel of rehabilitation programs after sport injuries, there is an uncertainty regarding the effectiveness of corresponding training interventions. The objective of this review was to evaluate the effectiveness of proprioceptive and neuromuscular training (PT/NT) for the treatment of ankle, knee, and shoulder joint injuries.Methods: Two independent reviewers performed a literature search in various databases and reference lists of articles. Data of included trials were then extracted, and methodological quality was assessed by using predetermined forms.Results: Fifteen trials met the inclusion criteria. PT/NT was effective at increasing functionality as well as at decreasing the incidence of recurrent injuries and ''giving way'' episodes after ankle sprains and in conservative treatment of anterior cruciate ligament injuries. However, conflicting results or no efficacy of training were reported for static postural control, joint position sense, neuromuscular control, joint laxity, and lower extremity strength. No study that examined PT/NT after shoulder injuries was found.Conclusions: From this review, it can be concluded that proprioceptive and neuromuscular interventions after ankle and knee joint injuries can be effective for the prevention of recurrent

Background The purpose of the study was to determine the changes over time in quadriceps strength and voluntary activation deficits after reconstruction of the anterior cruciate ligament. Methods Maximal voluntary contraction torque (MVC) and femoral nerve stimulation were used to measure quadriceps strength and voluntary activation deficits (VA) in both legs of 10 subjects with unilateral anterior cruciate ligament reconstruction immediately before and 4, 6, 8, 10, 12, 24, 36 and 48 weeks after surgery. To identify bilateral muscle inhibitions, 23 healthy participants served as controls. Results The results showed significant changes over time of the involved quadriceps for MVC (F = 31.152; P 0.01), whereas no VA deficits were found. Postoperatively, the MVC side-to-side differences lasted up to 12 weeks after surgery and the differences compared with the control group up to the 36 weeks. A unilateral VA deficit (P Conclusion The results revealed that MVC and VA fully reflect the functional status of the quadriceps muscle recovery during rehabilitation. In addition to the bilateral VA deficits compared with healthy controls, the operated leg is affected by an extra VA deficit immediately after surgery that should be considered for future rehabilitation programs.

Despite the common use of standardised methods analysing neuromuscular function during knee extension, there is a lack of test–retest reliability studies. Furthermore, for most of the investigated variables it is unknown which changes of values indicate an enhancement of performance. The aim of the present study was to investigate performance-dependent variations of muscle functions during isometric contraction of knee extensors and to examine test–retest reliability of their measurement methods. For test–retest reliability sports students completed three test sessions. Highly skilled athletes, sports students and untrained subjects were investigated to determine the performance-dependent variations. The following variables were analysed: maximal voluntary contraction (MVC), voluntary activation (VA), absolute muscle reaction time (AR), muscle endurance (ME), and EMG frequency analysis (MF) of m. vastus lateralis (VL), m. vastus medialis (VM) and m. rectus femoris (RF). Results test–retest-reliability: A high reliability between session 1 vs. 2 and session 2 vs. 3 was shown for MVC (ICC=0.92 and .97), VA (0.92/0.95) and ME (0.87/0.95). ICC in AR (0.23) was low between the first and second session and moderate between the second and third session (0.74). MF of VL, VM and RF showed low ICC between sessions. Performance dependent variations: Significant differences in nearly all variables (except VA) were found between trained (athletes and sports students) and untrained subjects.

Considering that proprioceptive deficits seem to be responsible for chronic ankle instability, the precise control of ankle angles during running may be impaired. Thus, the aim of the study was to evaluate the influence of chronic ankle instability on intra-individual variability of ankle kinematics during running.Lower extremity running gait kinematics of 12 recreational athletes with chronic ankle instability (mean age: 24 years, SD: 3 years; strides analyzed: 40.0, SD=1.7) and 12 matched healthy controls (mean age: 27 years, SD: 6 years; strides analyzed: 40.2, SD=2.5) were registered on a treadmill. Mean ankle angles (inversion/eversion, plantarflexion/dorsiflexion) and intra-individual standard deviations (variability) were calculated at each percent of the running gait cycle. Group differences were examined using statistical parameter mapping. To estimate effect sizes, Hedges' g was calculated.No group differences in the inversion/eversion or plantar-/dorsiflexion ankle angle were found. The inversion/eversion variability was significantly higher (P.050) in individuals with chronic ankle instability during the stance and swing phase. The highest Hedges' g values were registered at 15% (g=0.575, P.000) and 95% (g=0.551, P=.002) of the running gait cycle. The plantar-/dorsiflexion ankle angle variability showed no significant differences.Patients with chronic ankle instability exhibit a higher variability of ankle kinematics during running. This indicates altered sensorimotor control which is probably an underlying mechanism of chronic ankle instability. Thus, variability measures may help to better quantify treatment effects in future.

Background Exercise therapy following total hip replacement (THR) is considered to be important during the initial postoperative care, but till date only a few evidence-based recommendations exist. The aim of this survey was to identify prescription standards among different rehabilitation professionals, for the exercise therapy management after THR in Germany. Methods The study was a cross-sectional survey. Standardized questionnaires were sent to 38 eligible rehabilitation facilities in Germany. Participating surgeons, orthopaedic physicians, physiotherapists and exercise therapists rated the optimal early weight-bearing, resistance training, key components and dose of exercise therapy, and the hip loading during exercising. The returned questionnaires were then analyzed for level of agreement (≥80 %) among respondents. Results 313 rehabilitation professionals from 28 clinics returned completed questionnaires and were considered eligible for analysis. Out of total respondents, 53.9 % (cemented THR) and 18.2 % (uncemented THR) recommended full weight-bearing within five days after surgery. Commencement of resistance training later than three weeks after surgery is recommended by 20.6 % (36 %) for cemented (uncemented) prosthesis. Feedback varied significantly amongst the professions. Regarding the overall objectives of rehabilitation after hip replacement, respondents agree in six out of eight requested items. Agreement concerning priorities of specific exercises was achieved in three out of twelve items. The recommended exercise therapy dose varied significantly with working experience (p = 0.02). Conclusion Rehabilitation professionals mainly disagreed with the exercise therapy prescriptions following the total hip replacement during the initial postoperative care in Germany. Electronic supplementary material The online version of this article (doi:10.1186/s12891-015-0646-7) contains supplementary material, which is available to authorized users.

Possible benefits of barefoot running have been widely discussed in recent years. Uncertainty exists about which footwear strategy adequately simulates barefoot running kinematics. The objective of this study was to investigate the effects of athletic footwear with different minimalist strategies on running kinematics. Thirty-five distance runners (22 males, 13 females, 27.9 ± 6.2 years, 179.2 ± 8.4 cm, 73.4 ± 12.1 kg, 24.9 ± 10.9 km x week(-1)) performed a treadmill protocol at three running velocities (2.22, 2.78 and 3.33 m x s(-1)) using four footwear conditions: barefoot, uncushioned minimalist shoes, cushioned minimalist shoes, and standard running shoes. 3D kinematic analysis was performed to determine ankle and knee angles at initial foot-ground contact, rate of rear-foot strikes, stride frequency and step length. Ankle angle at foot strike, step length and stride frequency were significantly influenced by footwear conditions (p

Current approaches regarding injury prevention focus on the transfer of evidence into daily practice. One promising approach is to influence attitudes and beliefs of players. The objective of this study was to record player's perceptions on injury prevention. A survey was performed among players of one German high-level football (soccer) club. 139 professional and youth players between age 13 and 35 years completed a standardized questionnaire (response rate = 98%). It included categories with (1) history of lower extremity injuries, (2) perceptions regarding risk factors and (3) regularly used prevention strategies. The majority of players (84.2%) had a previous injury. 47.5% of respondents believe that contact with other players is a risk factor, followed by fatigue (38.1%) and environmental factors (25.9%). The relevance of previous injuries as a risk factor is differently perceived between injured (25%) and uninjured players (0.0%). Nearly all players (91.5%) perform stretching to prevent injuries, followed by neuromuscular warm up exercises (54.0%). Taping is used by 40.2% of previously injured players and 13.6% of players without a history of injuries. In conclusion, the perception of risk factors and performed preventive strategies are inconsistent with scientific evidence. Future transfer strategies should incorporate the players beliefs and attitudes.

To determine whether intensity and duration of standard exercise therapy are associated with changes in function after total hip arthroplasty (THA) and total knee arthroplasty (TKA).Prospective cohort study.Orthopedic inpatient rehabilitation center.A total of 123 patients 2 weeks after THA (n = 58; age, 62.5 ± 10.4 years) and TKA (n = 65; age, 66.6 ± 7.6 years).Standard rehabilitation (hands-on physiotherapy, group exercise therapy, strength training, cycle ergometer therapy, continuous passive motion therapy, and water exercise therapy).The Western Ontario and McMaster Universities Arthritis Index (WOMAC) and hip and knee range of motion (ROM) were assessed before and after inpatient rehabilitation.The individual rehabilitation period varied between 12-25 days and included 48.1 ± 12.5 (THA) or 41.9 ± 9.7 (TKA) exercise interventions with intensities between 9.6 and 14.0 points on the Borg Rate of Perceived Exertion Scale. WOMAC pain (P .001), stiffness (P.001), and function (P.001), as well as hip (P.001) and knee (P.001) ROM, improved significantly in THA and TKA patients. Analysis of covariance showed that these changes could not be explained by the total duration or mean intensity of exercise therapy.The findings show a low dose-response relationship between early postoperative exercise therapy and the improvements in function or ROM after THA and TKA. Although the findings raise questions about the efficacy of existing rehabilitation programs, the small sample size, single setting, and geographic differences in postoperative treatment standards limit the generalizability of findings.

In recreational sports, uncushioned, light-weight and minimalist shoes are increasingly used to imitate barefoot situations. Uncertainty exists whether these shoes provide sufficient stability during challenging movements. In this randomised crossover study, 35 healthy distance runners performed jump landing stabilisation and single-leg stance tests on a force plate, using four conditions in random order: barefoot, uncushioned minimalist shoes, cushioned ultraflexible shoes and standard running shoes. Ground reaction force (GRF) and centre of pressure (COP) data were used to determine unilateral jump landing stabilisation time and COP sway velocity during single-leg stance. Repeated measures analysis of variance revealed significant footwear interactions for medial-lateral (p < 0.001) and anterior-posterior COP sway velocity during standing (p < 0.001). The barefoot condition produced significantly greater postural sway velocities (p < 0.001) compared to all footwear conditions. No significant effects were found for jump landing stabilisation time. In conclusion, the results of this study indicate that increased shoe flexibility and reduced sole support have no, or only minor influence on static and dynamic postural control, and therefore, may not increase the risk of traumatic events during sports activities. However, barefoot conditions should be considered carefully when adequate postural control is needed.

Injury prevention effects of neuromuscular training have been partly attributed to postural control adaptations. Uncertainty exists regarding the magnitude of these adaptations and on how they can be adequately monitored. The objective was to determine the time course of neuromuscular training effects on functional, dynamic and static balance measures. Thirty youth (14.9 ± 3 years) field hockey athletes were randomised to an intervention or control group. The intervention included a 20-min neuromuscular warm-up program performed twice weekly for 10 weeks. Balance assessments were performed at baseline, week three, week six and post-intervention. They included the star excursion balance test (SEBT), balance error scoring system (BESS), jump-landing time to stabilization (TTS) and center of pressure (COP) sway velocity during single-leg standing. No baseline differences were found between groups in demographic data and balance measures. Adherence was at 86 %. All balance measures except the medial–lateral TTS improved significantly over time (p

In team sports, sensorimotor impairments resulting from previous injuries or muscular fatigue have been suggested to be factors contributing to an increased injury risk. Although it has been widely shown that physical fatigue affects static postural sway, it is still questionable as to what extent these adaptations are relevant for dynamic, sports-related situations. The objective of this study was to determine the effects of whole-body and localized fatigue on postural control in stable and unstable conditions. Nineteen male team handball players were assessed in 2 sessions separated by 1 week. Treadmill running and single-leg step-up exercises were used to induce physical fatigue. The main outcome measures were center of pressure (COP) sway velocity during a single-leg stance on a force plate and maximum reach distances of the star excursion balance test (SEBT). The COP sway velocity increased significantly (p < 0.05) after general (+47%) and localized fatigue (+10%). No fatigue effects were found for the SEBT. There were no significant correlations between COP sway velocity and SEBT mean reach in any condition. The results showed that although fatigue affects static postural control, sensorimotor mechanisms responsible for regaining dynamic balance in healthy athletes seem to remain predominantly intact. Thus, our data indicate that the exclusive use of static postural sway measures might not be sufficient to allow conclusive statements regarding sensorimotor control in the noninjured athlete population.

Background: It has been unclear which training mode is most effective and feasible for improving physical performance in the risk group of prefrail community-dwelling older adults. Objective: The purpose of the present study was to compare the effects of strength training (ST) versus power training (PT) on functional performance in prefrail older adults. This study was registered at clinicaltrials.gov as NCT00783159. Methods: 69 community-dwelling older adults (>65 years) who were prefrail according to the definition of Fried were included in a 12-week exercise program. The participants were randomized into an ST group, a PT group and a control group. All participants were supplemented with vitamin D3 orally before entering the intervention period. The primary outcome was the global score on the Short Physical Performance Battery (SPPB). Secondary outcomes were muscle power, appendicular lean mass (aLM) measured by dual energy X-ray absorptiometry and self-reported functional deficits (Short Form of the Late-Life Function and Disability Instrument, SF-LLFDI). Results: Regarding changes in the SPPB score during the intervention, significant heterogeneity between the groups was observed (p = 0.023). In pair-wise comparisons, participants in both training groups significantly (PT: p = 0.012, ST: 0.009) increased their SPPB score (PT: Δmean = 0.8, ST: Δmean = 1.0) compared to the control group, with no statistical difference among training groups (p = 0.301). No statistical differences were found in changes in aLM (p = 0.769), muscle power (p = 0.308) and SF-LLFDI (p = 0.623) between the groups. Muscle power significantly increased (p = 0.017) under vitamin D3 intake. Conclusions: In prefrail community-dwelling adults, PT is not superior to ST, although both training modes resulted in significant improvements in physical performance. With regard to dropout rates, ST appears to be advantageous compared to PT. The high prevalence of vitamin D3 deficiency and the slight improvement of physical performance under vitamin D3 supplementation among study participants underline the relevance of this approach in physical exercise interventions.

Purpose: The aim of this systematic review was to assess the effectiveness of proprioceptive/neuromuscular training in preventing sports injuries by using the best available evidence from methodologically well-conducted randomized controlled trials and controlled clinical trials without randomization. Methods: Two independent researchers performed a literature search in various electronic databases and reference lists. The reviewers independently assessed trials for inclusion criteria and methodological quality and extracted the data. Focusing on studies of high methodological quality, relative risks (RR) and 95% confidence intervals (CI) were used to estimate treatment effects. Results: From a total of 32 relevant studies, 7 methodologically well-conducted studies were considered for this review. Pooled analysis revealed that multi-intervention training was effective in reducing the risk of lower limb injuries (RR = 0.61, 95% CI = 0.49-0.77, P < 0.01), acute knee injuries (RR = 0.46, 95% CI = 0.28-0.76, P < 0.01), and ankle sprain injuries (RR = 0.50, 95% CI = 0.31-0.79, P < 0.01). Balance training alone resulted in a significant risk reduction of ankle sprain injuries (RR = 0.64, 95% CI = 0.46-0.9, P < 0.01) and a nonsignificant risk reduction for injuries overall (RR = 0.49, 95% CI = 0.13-1.8, P = 0.28). Exercise interventions were more effective in athletes with a history of sports injury than in those without. Conclusion: On the basis of the results of seven high-quality studies, this review showed evidence for the effectiveness of proprioceptive/neuromuscular training in reducing the incidence of certain types of sports injuries among adolescent and young adult athletes during pivoting sports. Future research should focus on the conduct of comparative trials to identify the most appropriate and effective training components for preventing injuries in specific sports and populations

Das vorliegende Kapitel zeigt zunachst auf, welche Uberlegungen fur eine effektive Planung und Umsetzung praventiver ernahrungs- und bewegungsorientierter Masnahmen erforderlich sind (▸ Kap. 10.1). Im Anschluss stellen die zwei folgenden Beitrage detailliert ernahrungs- und bewegungsbedingte Praventionsmoglichkeiten zur Vermeidung von Beeintrachtigungen und Erkrankungen des Muskel-Skelett-Systems dar (▸ Kap. 10.2 bzw. ▸ Kap. 10.3). Fur erfolgreiche Praventionsmasnahmen ist jedoch nicht nur das Wissen um eine gesundheitsforderliche Ernahrung und korperliche Aktivitat bei den unterschiedlichen Bevolkerungsgruppen von Bedeutung. Ebenfalls berucksichtigt werden muss das Wissen um Moglichkeiten der Motivation, den individuellen Lebensstil gesundheitsforderlicher zu gestalten. Dies zeigt ▸ Kap. 10.4 anhand eines theoretischen Modells am Beispiel der korperlichen Aktivitat auf. Nachfolgend verdeutlichen zwei Praxisprojekte, eines in der Schule (▸ Kap. 10.5) und eines im Kindergarten (▸ Kap. 10.6), wie Kinder und Jugendliche zu vermehrter korperlicher Aktivitat angeregt werden konnen.

Objective: As a result of inconsistencies in reported findings, controversy exists regarding the effectiveness of balance training for improving functional performance and neuromuscular control. Thus, its practical benefit in athletic training remains inconclusive. Our objective was to evaluate the effectiveness of training interventions in enhancing neuromuscular control and functional performance. Data Sources: Two independent reviewers performed a literature search in Cochrane Bone, Joint and Muscle Trauma Group Register and Cochrane Controlled Trials Register, MEDLINE, EMBASE, PEDro (Physiotherapy Evidence Database), and SCOPUS. Study Selection: Randomized controlled trials and controlled trials without randomization with healthy and physically active participants aged up to 40 years old were considered for inclusion. Outcomes of interest were postural control, muscle strength, agility, jump performance, sprint performance, muscle reflex activity, rate of force development, reaction time, and electromyography. Data Extraction: Data of interest were methodologic assessment, training intervention, outcome, timing of the outcome assessment, and results. Standardized mean differences and 95% confidence intervals were calculated when data were sufficient. Data Synthesis: In total, 20 randomized clinical trials met the inclusion criteria. Balance training was effective in improving postural sway and functional balance when compared with untrained control participants. Larger effect sizes were shown for training programs of longer duration. Although controversial findings were reported for jumping performance, agility, and neuromuscular control, there are indications for the effectiveness of balance training in these outcomes. When compared with plyometric or strength training, conflicting results or no effects of balance training were reported for strength improvements and changes in sprint performance. Conclusions: We conclude that balance training can be effective for postural and neuromuscular control improvements. However, as a result of the low methodologic quality and training differences, further research is strongly recommended.