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1.
Older runners are at greater risk of certain running-related injuries. Previous work demonstrated that aging influences running biomechanics, and suggest a compensatory relation between changes in the proximal and distal joints. Previous comparisons of interjoint coordination strategies between young and older runners could potentially have missed relevant differences by averaging coordination measures across time.ObjectiveTo compare coordination strategies between male runners under the age of 30 to those over the age of 60.MethodsTwelve young (22 ± 3 yrs, 1.80 ± 0.07 m, 78.0 ± 12.1 kg) and 12 older (63 ± 3 yrs, 1.78 ± 0.06 m, 73.2 ± 15.8 kg) male runners ran at 3.35 m/s on an instrumented treadmill. Ankle frontal plane, tibial transverse plane, knee sagittal plane, and hip frontal plane motion were measured. Inter-joint coordination was calculated using a modified vector coding technique. Coordination patterns and variability time series were compared between groups throughout stance using ANOVA for circular data.ResultsAt the ankle, older runners use in-phase propulsion (inversion, tibia external rotation) pattern following midstance (46–47% stance) while young runners are still in an in-phase collapse pattern (eversion, tibia external rotation). In coordination of the knee and hip, older runners maintained an in-phase collapse pattern (knee flexion, hip adduction) approaching midstance (35–37% stance), while younger runners use an out of phase strategy (knee extension, hip adduction). In coordination of the ankle and hip in the frontal plane, older runners again maintained an in phase collapse pattern up to midstance (34–39% stance), while younger runners used an out of phase strategy (ankle inversion, hip adduction). Variability was similar between age groups.ConclusionOlder runners appear to display altered coordination patterns during mid-stance, which may indicate protective biomechanical adaptations. These changes may also have implications for performance in older runners.  相似文献   

2.
BackgroundObstacle circumvention is a challenging task in Parkinson's disease (PD). Body segments adjustments, such as changing the direction of the trunk, followed by a change in the direction of the head, and modifications in the positioning of the feet, are necessary to circumvent an obstacle during walking. For that, individuals need to identify the distance to the obstacle, its characteristics (such as its dimension), and perform well-coordinated movements. However, PD is characterized by rigidity, which may be increased in the axial axis and compromise the task execution. Also, worsening sensory integration in PD may increase the time to perform these body segments adjustments, thus impairing the movement coordination when starting obstacle circumvention near to the obstacle.AimTo determine if the starting distance (1.5 m, 3 m, or 5 m) from the obstacle could modify the intersegmental coordination (specifically, the coordination between head, trunk, and pelvis) during the obstacle circumvention steps in individuals with PD.MethodsFourteen individuals with a diagnosis of idiopathic PD and 15 neurologically healthy individuals (CG) from the community were included in this study. The participants were evaluated in three different gait conditions, according to the starting distance from the obstacle: 1.5 m, 3 m, and 5 m away from the obstacle. Vector coding technique was employed to establish the coupling between head, trunk, and pelvis in the steps immediately before and during obstacle circumvention. Three-way ANOVA's (group, distance, and step) were calculated with the level of significance at p < 0.05.ResultsFor all couplings of coordination, there were no effects of distance. However, significant main effects of group and steps (p < 0.05) were found for all couplings with different patterns of coordination: head/pelvis (group: in-phase and anti-phase variables; steps: anti-phase variable), head/trunk (group: trunk variable; steps: in-phase and anti-phase variables) and trunk/pelvis (group: anti-phase; steps: trunk and pelvis). Finally, only head/trunk coupling showed an interaction between group*steps. Individuals with PD showed 7.95% lower head movement (p < 0.024) and 14.85% greater trunk movement than CG (p < 0.002). Also, individuals with PD performed 17.56% greater head movement in the step before the circumvention compared to the step during circumvention (p < 0.044).ConclusionThe starting distance from the obstacle did not influence the pattern of axial intersegmental coordination in both groups. However, how these segments interact in the preparation and during the obstacle circumvention are opposite in individuals with PD. While on the previous step to obstacle circumvention, the head movement was greater than the trunk, during the obstacle circumvention step, individuals with PD rotated the trunk more.  相似文献   

3.
Inter-segmental coordination can be influenced by chronic low back pain (CLBP). The sagittal plane lower extremities inter-segmental coordination pattern and variability, in conjunction with the pelvis and trunk, were assessed in subjects with and without non-specific CLBP during free-speed walking. Kinematic data were collected from 10 non-specific CLBP and 10 non-CLBP control volunteers while the subjects were walking at their preferred speed. Sagittal plane time-normalized segmental angles and velocities were used to calculate continuous relative phase for each data point. Mean absolute relative phase (MARP) and deviation phase (DP) were derived to quantify the trunk-pelvis and bilateral pelvis-thigh, thigh-shank and shank-foot coordination pattern and variability over the stance and swing phases of gait. Mann-Whitney U test was employed to compare the means of DP and MARP values between two groups (same side comparison). Statistical analysis revealed more in-phase/less variable trunk-pelvis coordination in the CLBP group (P < 0.05). CLBP group demonstrated less variable right or left pelvis-thigh coordination pattern (P < 0.05). Moreover, the left thigh-shank and left shank-foot MARP values in the CLBP group, were more in-phase than left MARP values in the non-CLBP control group during the swing phase (P < 0.05). In conclusion, the sagittal plane lower extremities, pelvis and trunk coordination pattern and variability could be generally affected by CLBP during walking. These changes can be possible compensatory strategies of the motor control system which can be considered in the CLBP subjects.  相似文献   

4.
This study aimed to analyze the effect of different knee starting angles on jump performance, kinetic parameters, and intersegmental coupling coordination during a squat jump (SJ) and a countermovement jump (CMJ). Twenty male volleyball and basketball players volunteered to participate in this study. The CMJ was performed with knee flexion at the end of the countermovement phase smaller than 90° (CMJ<90), greater than 90° (CMJ>90), and in a preferred position (CMJPREF), while the SJ was performed from a knee angle of 70° (SJ70), 90° (SJ90), 110° (SJ110), and in a preferred position (SJPREF). The best jump performance was observed in jumps that started from a higher squat depth (CMJ<90–SJ70) and in the preferred positions (CMJ and SJ), while peak power was observed in the SJ110 and CMJ>90. Analysis of continuous relative phase showed that thigh–trunk coupling was more in-phase in the jumps (CMJ and SJ) performed with a higher squat depth, while the leg–thigh coupling was more in-phase in the CMJ>90 and SJPREF. Jumping from a position with knees more flexed seems to be the best strategy to achieve the best performance. Intersegmental coordination and jump performance (CMJ and SJ) were affected by different knee starting angles.  相似文献   

5.
This study investigated the relation between postural movement and upper-limb coordination stability. Adults produced bimanual circles using in-phase and anti-phase coordination patterns in time to an increasing rate metronome (i.e., movement-time instruction) in the horizontal (e.g., tabletop) and vertical (e.g., "wall" perpendicular to body) planes. All participants produced the instructed in- and anti-phase patterns. Coordination stability (i.e., SD of relative phase) was larger for anti-phase than in-phase patterns in both planes; however, anti-phase coordination stability was lower in the vertical plane than in the horizontal plane. Torso movement was larger during anti-phase coordination patterns in the horizontal plane, whereas it was larger during in-phase coordination patterns in the vertical plane. These results indicate that different orientations of the same task can produce different results for stability of coordination. This information may be important for performing and learning complex motor-coordination movements (e.g., playing musical instruments).  相似文献   

6.
The purpose of this study was to identify changes in segment/joint coordination and coordination variability in running with increasing head stability requirements. Fifteen strides from twelve recreational runners while running on a treadmill at their preferred speed were collected. Head stability demands were manipulated through real-time visual feedback that required head-gaze orientation to be contained within boxes of different sizes, ranging from 21 to 3 degrees of visual angle in 3-degree decrements. Coordination patterns and coordination variability were assessed between head and trunk segments, hip and knee joints, and knee and ankle joints in the three cardinal planes, respectively. Mean coupling angles and the standard deviation of the coupling angles at each individual point of the stance phase were calculated using a modified vector coding technique and circular statistics. As head stability demands increased, transverse plane head-trunk coordination was more anti-phase and showed increased head‑leading and decreased trunk‑leading patterns; for the lower extremity, there was increased in-phase and decreased anti-phase sagittal plane coordination. Increased head stability demands also resulted in an increase in coordination variability for both upper body and lower extremity couplings during the second half of the stance phase. Overall, the results provide evidence that coordinative adaptations to increasing head stability demands occur throughout the entire body: 1) through more independent control of the head relative to the trunk; 2) by increasing in-phase coordination between lower extremity joints, and 3) through increased coordination variability in the second half of stance in both upper body segmental and lower extremity joint couplings. These adaptations likely contribute to the reduction of the range of motion of the trunk in vertical direction.  相似文献   

7.
The current study investigated interlimb coordination in individuals with traumatic brain injury (TBI) during overground walking. The study involved 10 participants with coordination, balance, and gait abnormalities post-TBI, as well as 10 sex- and age-matched healthy control individuals. Participants walked 12 m under two experimental conditions: 1) at self-selected comfortable walking speeds; and 2) with instructions to increase the amplitude and out-of-phase coordination of arm swinging. The gait was assessed with a set of spatiotemporal and kinematic parameters including the gait velocity, step length and width, double support time, lateral displacement of the center of mass, the amplitude of horizontal trunk rotation, and angular motions at shoulder and hip joints in sagittal plane. Interlimb coordination (coupling) was analyzed as the relative phase angles between the left and right shoulders, hips, and contralateral shoulders and hips, with an ideal out-of-phase coupling of 180° and ideal in-phase coupling of 0°. The TBI group showed much less interlimb coupling of the above pairs of joint motions than the control group. When participants were required to increase and synchronize arm swinging, coupling between shoulder and hip motions was significantly improved in both groups. Enhanced arm swinging was associated with greater hip and shoulder motion amplitudes, and greater step length. No other significant changes in spatiotemporal or kinematic gait characteristics were found in either group. The results suggest that arm swinging may be a gait parameter that, if controlled properly, can improve interlimb coordination during overground walking in patients with TBI.  相似文献   

8.
This study assessed perception–action coupling in expert swimmers by focusing on their upper limb inter-segmental coordination in front crawl. To characterize this coupling, we manipulated the fluid flow and compared trials performed in a swimming pool and a swimming flume, both at a speed of 1.35 m s−1. The temporal structure of the stroke cycle and the spatial coordination and its variability for both hand/lower arm and lower arm/upper arm couplings of the right body side were analyzed as a function of fluid flow using inertial sensors positioned on the corresponding segments. Swimmers’ perceptions in both environments were assessed using the Borg rating of perceived exertion scale. Results showed that manipulating the swimming environment impacts low-order (e.g., temporal, position, velocity or acceleration parameters) and high-order (i.e., spatial-temporal coordination) variables. The average stroke cycle duration and the relative duration of the catch and glide phases were reduced in the flume trial, which was perceived as very intense, whereas the pull and push phases were longer. Of the four coordination patterns (in-phase, anti-phase, proximal and distal: when the appropriate segment is leading the coordination of the other), flume swimming demonstrated more in-phase coordination for the catch and glide (between hand and lower arm) and recovery (hand/lower arm and lower arm/upper arm couplings). Conversely, the variability of the spatial coordination was not significantly different between the two environments, implying that expert swimmers maintain consistent and stable coordination despite constraints and whatever the swimming resistances. Investigations over a wider range of velocities are needed to better understand coordination dynamics when the aquatic environment is modified by a swimming flume. Since the design of flumes impacts significantly the hydrodynamics and turbulences of the fluid flow, previous results are mainly related to the characteristics of the flume used in the present study (or a similar one), and generalization is subject to additional investigations.  相似文献   

9.
ObjectivesAnalogy instruction has an advantage on motor skill learning. The effect of analogy instructional type on kinematics, particularly on inter-joint coordination, is an extremely understudied area of research. Against this background, this paper experimentally controlled the quality and quantity of the to-be-learned information included in instruction and applied principal component analysis (PCA) to time-series data of joint angles to examine whether different instruction methods could change inter-joint coordination structure.Methods and designForty-five novice participants, fifteen each for three independent groups, performed dart-throwing training with either explicit, rule-based biomechanical metaphor (RBM), or information-integrated biomechanical metaphor (IIM) instructions. Performance and kinematics were evaluated in pre-test, retention test, and transfer test that can increase psychological pressure. The dependent variables were performance outcome, joint variability, and measurements derived from PCA.ResultsAnalyses revealed a significant test effect for the performance outcome, joint variability, and PCA measurements. No significant group effect or group–test interaction was found for the performance outcome and joint variability. Significant test effect and test–group interaction were found for the wrist PC1 loading. The IIM group means significantly increased in the retention and transfer tests. The explicit and RBM group means showed no significant effects of the test. These results suggest that IIM learners significantly changed the PCA structure in the retention test and maintained it in the transfer test, whereas explicit and RBM learners did not.ConclusionsThe findings provide the first insight into the effects of information-integrated biomechanical metaphors on the acquisition of inter-joint coordination structures for novice learners.  相似文献   

10.
The Microsoft Kinect has been used in studies examining posture and gait. Despite the advantages of portability and low cost, this device has not been used to assess interlimb coordination. Fundamental insights into movement control, variability, health, and functional status can be gained by examining coordination patterns. In this study, we investigated the efficacy of the Microsoft Kinect to capture bimanual coordination relative to a research-grade motion capture system. Twenty-four healthy adults performed coordinated hand movements in two patterns (in-phase and antiphase) at eight movement frequencies (1.00–3.33 Hz). Continuous relative phase (CRP) and discrete relative phase (DRP) were used to quantify the means (mCRP and mDRP) and variability (sdCRP and sdDRP) of coordination patterns. Between-device agreement was assessed using Bland–Altman bias with 95 % limits of agreement, concordance correlation coefficients (absolute agreement), and Pearson correlation coefficients (relative agreement). Modest-to-excellent relative and absolute agreements were found for mCRP in all conditions. However, mDRP showed poor agreement for the in-phase pattern at low frequencies, due to large between-device differences in a subset of participants. By contrast, poor absolute agreement was observed for both sdCRP and sdDRP, while relative agreement ranged from poor to excellent. Overall, the Kinect captures the macroscopic patterns of bimanual coordination better than coordination variability.  相似文献   

11.
The coordination of multiple body segments (torso and legs) in the control of standing posture during a suprapostural task was studied. The analysis was motivated by dynamical theories of motor coordination. In 2 experiments it was found that multisegment postural coordination could be described by the relative phase of rotations around the hip and ankle joints. The effective length of the feet, the height of the center of mass, and the amplitude of head motions in a visual tracking task were varied. Across these variations, 2 modes of hip-ankle coordination were observed: in-phase and anti-phase. The emergence of these modes was influenced by constraints imposed by the suprapostural tracking task, supporting the idea that such tasks influence postural control in an adaptive manner. Results are interpreted in terms of a dynamical approach to coordination in which postural coordination modes can be viewed as emergent phenomena.  相似文献   

12.
Multiple joint interactions are critical to produce stable coordinated movements and can be influenced by low back pain and task conditions. Inter-segmental coordination pattern and variability were assessed in subjects with and without chronic nonspecific low back pain (CNSLBP). Kinematic data were collected from 22 CNSLBP and 22 healthy volunteers during repeated trunk flexion–extension in various conditions of symmetry, velocity, and loading; each at two levels. Sagittal plane angular data were time normalized and used to calculate continuous relative phase for each data point. Mean absolute relative phase (MARP) and deviation phase (DP) were derived to quantify lumbar–pelvis and pelvis–thigh coordination patterns and variability. Statistical analysis revealed more in-phase coordination pattern in CNSLBP (p = 0.005). There was less adaptation in the DP for the CNSLBP group, as shown by interactions of Group by Load (p = .008) and Group by Symmetry by Velocity (p = .03) for the DP of pelvis–thigh and lumbar–pelvis couplings, respectively. Asymmetric (p < 0.001) and loaded (p = 0.04) conditions caused less in-phase coordination. Coordination variability was higher during asymmetric and low velocity conditions (p < 0.001). In conclusion, coordination pattern and variability could be influenced by trunk flexion–extension conditions. CNSLBP subjects demonstrated less adaptability of movement pattern to the demands of the flexion–extension task.  相似文献   

13.
The purpose of this study was to evaluate the effectiveness of an aerobics games class on creativity in children during the school day. Participants were 96 students (age = 9.84 ± 1.12 years), 48 girls and 48 boys. The students were randomly assigned to the experimental group (EG, n = 48) or the control group (CG, n = 48). The Prueba de Imaginación Creativa-Niños (PIC-N) test was employed to assess narrative and graphic creativity. The EG took part in an aerobic games session lasting 45 min; the CG did not take part in a physical education class on that school day. As for group × time interaction, the EG experienced significant improvements in all creativity variables except in graphic originality, graphic titles, and graphic details. The CG did not improve any creativity variables. The findings suggest that acute aerobic exercise can enhance students’ creativity, which could be important for academic achievement.  相似文献   

14.
Currently, there are limited data regarding the practice of genetic counseling for whole exome sequencing (WES). Improved understanding of how genetic counselors and other providers are educating, counseling, and communicating results may identify practice trends, and patient or provider needs. Between April 2013 and December 2014, we surveyed providers who ordered WES testing from GeneDx, a CLIA-certified laboratory. Forty-nine respondents completed the survey; 41 % of participants reported board certification in genetic counseling. Pre-test and post-test counseling was completed in all but one case each. Pre-test counseling lasted less than 1 h for 53 % of cases and 1 to 2 h for 43 %. Topics discussed with all patients included consent for testing, and incidental findings; other topics were variable. In contrast to pre-test counseling, 59 % reported post-test counseling lasting 1 to 2 h and 33 % less than an hour; post-testing counseling was significantly longer in cases with a definitive diagnosis than those without (p?=?0.0129). The survey findings indicate some variability regarding the amount of time spent on counseling and the topics discussed during pre-test counseling. Additional exploration, patient and provider educational resources, and potentially more specific guidelines regarding counseling for WES may be warranted.  相似文献   

15.
BackgroundWhen completing grip-selection tasks, healthy adults generally plan for the most comfortable end-posture which is termed the end-state comfort (ESC) effect. Children with and without developmental coordination disorder (DCD) are less likely to plan for ESC which begs the question as to whether they are not able to perform this type of planning or whether they prioritize other aspects of the task.Aims(1) Examine if children with and without probable DCD (pDCD) are able to plan for ESC if they are explicitly instructed to and (2) if this transfers to another similar task. (3) Examine if children with and without pDCD perceive the level of comfort of the grips that they use differently and if this relates to ESC planning.MethodsTwelve children with and 12 children without probable DCD (pDCD) (aged 5–9 years) received a 10-min training session in which children were explicitly instructed to end their movement in ESC, after which they formulated their own plan to reach this goal. The study consisted of a pre-post-test design in which changes in the proportion of ESC were analyzed on the task that was trained as well as on an untrained transfer-task. Furthermore, the perceived level of comfort was examined.ResultsBoth groups of children showed a higher proportion of ESC on the post-test compared with the pre-test, on the task that was trained as well as on the transfer-task. There were no group differences regarding the perceived level of comfort of the different grip postures.ConclusionThe majority of the children with and without pDCD seems to be able to adjust their planning strategy and prioritize ESC if they are explicitly instructed to.  相似文献   

16.
In 3 experiments, the author tested the hypothesis that coordination dynamics is the content of a generalized motor program (GMP) for rhythmic interlimb coordination. In Experiment 1, learners (N = 14) practiced a ?90° movement with either identically timed or differently timed limbs. Both acquisition and transfer to novel (effector and pattern) timings were unaffected by the learning condition and were suggestive of the intrinsic dynamics for in-phase and antiphase. In Experiment 2, learners' (N = 13) acquisition of 2 different phase relations (?90° and ?45°) was qualitatively identical. Attractor reconstruction revealed an increase in the predictability of individual movement trajectories and a decrease in attractor dimensionality over learning. Transfer for both ?90° and ?45° was again suggestive of the intrinsic dynamics. In Experiment 3, learning altered participants' (N = 8) performance of in-phase and antiphase relations. Together, the results suggested a single continuum of phase relations, called an attractor landscape, that produces similar patterns of CE and VE for both previously stable and learned coordinations.  相似文献   

17.
The attractors of bimanual rhythmic coordination are given as the solutions of a motion equation in relative phase. How are those attractors affected by cognitive activity? In 3 experiments, participants (N = 10 in Experiments 1 and 2; N = 5 in Experiment 3) were required to produce in-phase or antiphase coordination while they either did or did not perform an information-reduction task. The average absolute deviation from in-phase (0 degrees ) and antiphase (180 degrees ) satisfying a particular parameterization of the motion equation was amplified by cognitive activity. That amplification of absolute phase shift was the same for both in-phase and antiphase coordination. Furthermore, the amplification (in degrees) increased linearly with the magnitude of cognitive activity (in bits). Cognitive activity had limited influence on the variability of relative phase and did not affect its average signed deviation. Collectively, the results suggest that cognitive activity produces a shift in the attractors of bimanual coordination dynamics that is directionally nonspecific and is independent of movement speed, detuning, and the in-phase-antiphase distinction.  相似文献   

18.
IntroductionDepression and anxiety are important risk factors for diabetes and high blood pressure.ObjectiveThis study investigated the effectiveness of the Cognitive-Behavioral Group Intervention for Diabetes Disease (CBGI-DD) in reducing depression and anxiety in female patients with type 2 diabetes (T2D).MethodThe CBGI-DD program includes 12 weekly 2.5 h sessions, spread weekly over the course of 3 months. The present study was semi-experimental and controlled, with assessments at pre-test and post-test. It included diagnostic criteria for the diagnosis of T2D in the patient's medical records by a diabetes specialist. Participants (62 female volunteers aged 25 to 75 years) were randomly allocated to a control or test group. Both groups responded to the Second edition of the Beck Depression Inventory (BDI-II) and the Beck Anxiety Inventory (BAI) before (pretest) and immediately after the intervention (posttest). Participants in the test group received CBGI-DD (from April up to the end of September 2018) at Mashhad Diabetes Center. The control group received only medical care during this period.ResultsAn analysis of covariance showed that compared to the control group, the test group had a significant reduction in anxiety and depression from pre-test to post-test (p < 0.05). It was compared post-test scores between the two groups, controlling for pre-test scores.ConclusionThe CBGI-DD program seems to be effective in reducing anxiety and depression in female patients with T2D. However, further research exploring the potential for long-term improvements in depression and anxiety is needed.  相似文献   

19.
Abstract

Recent studies examining children diagnosed with Autism Spectrum Disorder (ASD) have revealed kinematic markers highlighting deficits in the preparatory and online phases of upper extremity movements. In the following study, 12 children with high functioning ASD were first assessed (pre-test) on 15 trials of a reciprocal upper extremity Fitts Law target task by flexing and extending their right arm in the horizontal plane between two targets as fast and accurately as possible. Following the initial assessment, the children either continued with 30 additional trials of the target task (control) or were asked to track a sine wave template (experimental). All participants were then assessed on 15 trials of the target test (post-test). Results reveal that tracking the sine wave template during training not only produced faster movements compared to the control but also produced these movements in a more harmonic way.  相似文献   

20.
Abstract

The aim was to assess dual- versus single-task training for motor performance and cognitive performance in adolescents. Two experiments were performed. In the first, 30 adolescents were randomized to three groups to determine the effect of dual-task difficulty on postural control: α-scaling and root mean square (RMS). In the second, 20 adolescents were randomized to two groups to determine the effect of dual-task practice to improve working memory. RMS in the post-test was lower than the pre-test in both dual-task groups, while α-scaling was lower in post-test than pre-test only in the high-difficulty dual-task group. A practice effect was observed on the percentage of correct answers only in the dual-task group (p?=?0.035). Thus, dual-task training could enhance motor and cognitive performance more than single-task training.  相似文献   

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