| 1. |
- Broström, Eva, et al.
(författare)
-
Trunk and center of mass movements during gait in children with juvenile idiopathic arthritis
- 2007
-
Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457 .- 1872-7646. ; 26:2, s. 296-305
-
Tidskriftsartikel (refereegranskat)abstract
- Motion of the body center of mass (CoM) can often indicate the overall effect of the strategy of forward progression used. In the present study, focus is placed on trunk movements in the sagittal, coronal, and transverse/rotation plane, as well as placement of the CoM, during gait in children with juvenile idiopathic arthritis (JIA). Seventeen children with JIA, all with polyarticular lower extremity involvement were examined before and approximately two weeks after treatment with intra-articular cortico-steroid injections. Movement was recorded with a 6-camera 3D motion analysis system in both the children with JIA and in 21 healthy controls. Trunk and center of mass movements were compared between JIA and controls, and effects of intra-articular cortico-steroid treatment were evaluated. Children with JIA were more posteriorly tilted in the trunk, contrary to the common clinical impression, and had their CoM placed more posterior and off-centred, which may have been a result of pain. With such knowledge, it might be possible to better understand the effects of their pain and involvement, and ultimately to plan a treatment strategy for improving their gait patterns.
|
|
| 2. |
- Byström, Anna, et al.
(författare)
-
Differences in rider movement pattern between different degrees of collection at the trot in high-level dressage horses ridden on a treadmill
- 2015
-
Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457 .- 1872-7646. ; 41, s. 1-8
-
Tidskriftsartikel (refereegranskat)abstract
- Collection is a central term in equine dressage, defined as a shortening of the horse's stride length with retained energy and hind limb activity. How collection is induced by the rider has yet not been investigated objectively. The aim of this study was therefore to compare the movement pattern of high-level dressage riders between free trot (loose reins), passage and a range of three speeds in collected trot.Both at higher speed in collected trot and in passage, the rider's pelvis became more caudally rotated and the rider's lumbar back became more flexed. However, in passage there was also a decrease in phase-shift between horse and rider movements, suggesting that the rider used the seat more actively. In free trot, the rider's pelvis was more cranially rotated, the lumbar back was more extended, the rider's body inclined more forwards, and the phase-shift between horse and rider was increased, compared to collected trot. The observed changes were partly explainable from changes in the horse's movement pattern. However, most differences in rider body position seemed unrelated to the horse's movements, but were in accordance with instructions in equestrian texts, suggesting that those changes were voluntarily adopted by the riders. (C) 2015 Elsevier B.V. All rights reserved.
|
|
| 3. |
- Byström, Anna, et al.
(författare)
-
Intersegmental strategies in frontal plane in moderately-skilled riders analyzed in ridden and un-mounted situations
- 2019
-
Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457 .- 1872-7646. ; 66, s. 511-520
-
Tidskriftsartikel (refereegranskat)abstract
- The symmetry of the rider is highly relevant, and in the equestrian community it is generally thought that a symmetrical rider has a better possibility to influence the horse in an optimal way. The aim of the study was to analyse and compare frontal plane kinematics of the core body segments in ten riders while riding and while rocking a balance chair from side-to-side. It was hypothesized that the riders were asymmetrical in relation to their intersegmental strategies when comparing between left and right directions and that individual riders would display the same postural strategies when riding and when rocking the balance chair. Ten moderately-skilled riders wore a full-body marker set that was tracked by a motion capture system as they rocked a balance chair from side to side. Inertial measurement units attached to the head, trunk and pelvis were used to measure the segmental movements while riding in left and right directions. Roll rotation data for head, trunk and pelvis were averaged over available strides/cycles. Results from mixed models showed that the riders were asymmetric when comparing riding in left vs right directions, for example the trunk was rotated 19 degrees to the right on the right circle and 14 degrees to the left on the left circle, on average. Riders adopted the same asymmetrical posture whether they were riding in the left or right direction on straight lines, circles or leg yielding. A significant relationship was found between postural asymmetries when riding and when rocking the balance chair, one degree of pelvis or head roll asymmetry on the chair predicted 2.4 (SE 0.9) degrees of asymmetry while riding. Future studies may investigate the value of seated, off-horse postural training for improving rider symmetry and thereby equestrian performance.
|
|
| 4. |
- Fabré, Nicolas, et al.
(författare)
-
Alterations in aerobic energy expenditure and neuromuscular function during a simulated cross-country skiathlon with the skating technique
- 2015
-
Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457 .- 1872-7646. ; 40, s. 326-340
-
Tidskriftsartikel (refereegranskat)abstract
- Here, we tested the hypothesis that aerobic energy expenditure (AEE) is higher during a simulated 6-km (2 loops of 3-km each) "skiathlon" than during skating only on a treadmill and attempted to link any such increase to biomechanical and neuromuscular responses. Six elite male cross-country skiers performed two pretesting time-trials (TT) to determine their best performances and to choose an appropriate submaximal speed for collection of physiological, biomechanical and neuromuscular data during two experimental sessions ((exp)). Each skier used, in randomized order, either the classical (CL) or skating technique (SK) for the first 3-km loop, followed by transition to the skating technique for the second 3-km loop. Respiratory parameters were recorded continuously. The EMG activity of the triceps brachii (TBr and vastus lateralis (VLa) muscles during isometric contractions performed when the skiers were stationary (i.e., just before the first loop, during the transition, and after the second loop); their corresponding activity during dynamic contractions; and pole and plantar forces during the second loop were recorded. During the second 3-km of the 'IT, skating speed was significantly higher for the SK-SK than CL-SK. During this second loop, AEE was also higher (+1.5%) for CL-SKexp than SK-SKexp, in association with higher VLa EMG activity during both isometric and dynamic contractions, despite no differences in plantar or pole forces, poling times or cycle rates. Although the underlying mechanism remains unclear, during a skiathlon, the transition between the sections of classical skiing and skating alters skating performance (i.e., skiing speed), AEE and neuromuscular function. (C) 2015 Elsevier B.V. All rights reserved.
|
|
| 5. |
- Green, Dido, et al.
(författare)
-
Does subtype of developmental coordination disorder count : Is there a differential effect on outcome following intervention?
- 2008
-
Ingår i: Human Movement Science. - : Elsevier. - 0167-9457 .- 1872-7646. ; 27:2, s. 363-382
-
Tidskriftsartikel (refereegranskat)abstract
- It is well known that developmental coordination disorder (DCD) is a heterogeneous condition in which children frequently present with co-occurring conditions in addition to their motor difficulties. This study considered whether there would be a differential effect of a group treatment program on subtypes of perceptual and movement problems or associated co-occurring conditions. A subset of children (n = 43) from a larger clinical sample (n = 100) with DCD participated in a 2 frac(1, 4) year cross-over intervention study which followed the cognitive orientation to daily occupational performance (CO-OP) approach. Original subtypes were determined by contrasting the current sample with previously published subtyping studies in DCD [Hoare, D. (1994). Subtypes of developmental coordination disorder. Adapted Physical Activity Quarterly, 11, 158-169; Macnab, J. J., Miller, L. T., & Polatajko, H. J. (2001). The search for subtypes of DCD: Is cluster analysis the answer? Human Movement Science, 20, 49-72]. No advantage was conferred to any subtype although children with more profound and complex difficulties at initial assessment, despite progress following intervention, were most likely to have continuing difficulties at the end of the project.
|
|
| 6. |
- Gutierrez-Farewik, Elena M., et al.
(författare)
-
Comparison and evaluation of two common methods to measure center of mass displacement in three dimensions during gait
- 2006
-
Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457 .- 1872-7646. ; 25:2, s. 238-256
-
Tidskriftsartikel (refereegranskat)abstract
- Center of mass displacement during gait has frequently been used as an indicator of gait efficiency or as a complement to standard gait analysis. With technological advances, measuring the center of mass as the centroid of a multi-segment system is practical and feasible, but must first be compared to the well-established Newtonian computation of double-integrating the ground reaction force. This study aims to verify that the kinematic centroid obtained from a commonly-used model (Vicon Peak (R) Plug-In-Gait) provides at least as reliable measurements of center of mass displacement as those obtained from the ground reaction forces. Gait data was collected for able-bodied children and children with myelomeningocele who use larger lateral center of mass excursions during gait. Reasonable agreement between methods was found in fore-aft and vertical directions, where the methods' excursions differed by an average of less than 10 mm in either direction, and the average RMS differences between methods' computed curves were 6 and 13 mm. Particularly good agreement was observed in the lateral direction, where the calculated excursions differed by an average of less than 2 mm and the RMS difference was 5 mm. Error analyses in computing the center of mass displacement from ground reaction forces were performed. A 5% deviation in mass estimation increased the computed vertical excursion twofold, and a 5% deviation in the integration constant of initial velocity increased the computed fore-aft excursions by 10%. The suitability of calculating center of mass displacement using ground reaction forces in a patient population is questioned. The kinematic centroid is susceptible to errors in segment parameters and marker placement, but results in plausible results that are at least within the range of doubt of the better-established ground reaction force integration, and are more useful when interpreting 3-D gait data.
|
|
| 7. |
- Hafström, Anna, et al.
(författare)
-
Effectuation of adaptive stability and postural alignment strategies are decreased by alcohol intoxication.
- 2014
-
Ingår i: Human Movement Science. - : Elsevier BV. - 1872-7646 .- 0167-9457. ; 35:Apr 29, s. 30-49
-
Tidskriftsartikel (refereegranskat)abstract
- Human stability control is a complex process comprising contributions from several partly independent mechanisms such as coordination, feedback and feed-forward control, and adaptation. Acute alcohol intoxication impairs these functions and is recognized as a major contributor to fall traumas. The study aimed to investigate how alcohol intoxication at .06% and .10% blood alcohol concentration (BAC) affected the movement spans and control of posture alignment. The angular positions of the head, shoulder, hip and knees relative to the ankles were measured with a 3D motion analysis system in 25 healthy adults during standing with eyes open or closed and with or without vibratory balance perturbations. Alcohol intoxication significantly increased the movement spans of the head, shoulders, hip and knees in anteroposterior and lateral directions during quiet stance (p⩽.047 and p⩽.003) and balance perturbations (p<.001, both directions). Alcohol intoxication also decreased the ability to reduce the movement spans through adaptation in both anteroposterior (p⩽.011) and lateral (p⩽.004) directions. When sober and submitted to balance perturbations, the subjects aligned the head, shoulders, hip and knees more forward relative to the ankle joint (p<.001), hence adopting a more resilient posture increasing the safety margin for backward falls. Alcohol intoxication significantly delayed this forward realignment (p⩽.022). Alcohol intoxication did not cause any significant posture realignment in the lateral direction. Thus, initiation of adaptive posture realignments to alcohol or other disruptions might be context dependent and associated with reaching a certain level of stability threats.
|
|
| 8. |
- Johansson, Jonas, 1984-, et al.
(författare)
-
Predicting incident falls : Relationship between postural sway and limits of stability in older adults
- 2019
-
Ingår i: Human Movement Science. - : Elsevier. - 0167-9457 .- 1872-7646. ; 66, s. 117-123
-
Tidskriftsartikel (refereegranskat)abstract
- Background We have previously shown that objective measurements of postural sway predicts fall risk, although it is currently unknown how limits of stability (LOS) might influence these results.Research question: How integrated postural sway and LOS measurements predict the risk of incident falls in a population-based sample of older adults.Methods: The sample for this prospective observational study was drawn from the Healthy Ageing Initiative cohort and included data collected between June 2012 and December 2016 for 2396 men and women, all 70 years of age. LOS was compared to postural sway with measurements during eyes-open (EO) and eyes-closed (EC) trials, using the previously validated Wii Force Plate. Fall history was assessed during baseline examination and incident falls were collected during follow-up at 6 and 12 months. Independent predictors of incident falls and additional covariates were investigated using multiple logistic regression models.Results: During follow-up, 337 out of 2396 participants (14%) had experienced a fall. Unadjusted regression models from the EO trial revealed increased fall risk by 6% (OR 1.06, 95% CI 1.02–1.11) per each centimeter squared increase in sway area and by 16% (OR 1.16, 95% CI 1.07–1.25) per 1-unit increase in Sway-Area-to-LOS ratio. Odds ratios were generally lower when analyzing EC trials and only slightly attenuated in fully adjusted models.Significance: Integrating postural sway and LOS parameters provides valid fall risk prediction and a holistic analysis of postural stability. Future work should establish normative values and evaluate clinical utility of these measures.
|
|
| 9. |
|
|
| 10. |
- Ma, Christina Zong-Hao, et al.
(författare)
-
A wearable vibrotactile biofeedback system improves balance control of healthy young adults following perturbations from quiet stance
- 2017
-
Ingår i: Human Movement Science. - : Elsevier. - 0167-9457 .- 1872-7646. ; 55, s. 54-60
-
Tidskriftsartikel (refereegranskat)abstract
- Maintaining postural equilibrium requires fast reactions and constant adjustments of the center of mass (CoM) position to prevent falls, especially when there is a sudden perturbation of the support surface. During this study, a newly developed wearable feedback system provided immediate vibrotactile clues to users based on plantar force measurement, in an attempt to reduce reaction time and CoM displacement in response to a perturbation of the floor. Ten healthy young adults participated in this study. They stood on a support surface, which suddenly moved in one of four horizontal directions (forward, backward, left and right), with the biofeedback system turned on or off. The testing sequence of the four perturbation directions and the two system conditions (turned on or off) was randomized. The resulting reaction time and CoM displacement were analysed. Results showed that the vibrotactile feedback system significantly improved balance control during translational perturbations. The positive results of this preliminary study highlight the potential of a plantar force measurement based biofeedback system in improving balance under perturbations of the support surface. Future system optimizations could facilitate its application in fall prevention in real life conditions, such as standing in buses or trains that suddenly decelerate or accelerate.
|
|
| 11. |
- Pellegrini, Barbara, et al.
(författare)
-
Biomechanical and energetic determinants of technique selection in classical cross-country skiing
- 2013
-
Ingår i: Human Movement Science. - : Elsevier. - 0167-9457 .- 1872-7646. ; 32:6, s. 1415-1429
-
Tidskriftsartikel (refereegranskat)abstract
- Classical cross-country skiing can be performed using three main techniques: diagonal stride (DS), double poling (DP), and double poling with kick (DK). Similar to other forms of human and animal gait, it is currently unclear whether technique selection occurs to minimize metabolic cost or to keep some mechanical factors below a given threshold. The aim of this study was to find the determinants of technique selection. Ten male athletes roller skied on a treadmill at different slopes (from 0° to 7° at 10km/h) and speeds (from 6 to 18km/h at 2°). The technique preferred by skiers was gathered for every proposed condition. Biomechanical parameters and metabolic cost were then measured for each condition and technique. Skiers preferred DP for skiing on the flat and they transitioned to DK and then to DS with increasing slope steepness, when increasing speed all skiers preferred DP. Data suggested that selections mainly occur to remain below a threshold of poling force. Second, critically low values of leg thrust time may limit the use of leg-based techniques at high speeds. A small role has been identified for the metabolic cost of locomotion, which determined the selection of DP for flat skiing.
|
|
| 12. |
- Rudisch, J., et al.
(författare)
-
Kinematic parameters of hand movement during a disparate bimanual movement task in children with unilateral Cerebral Palsy
- 2016
-
Ingår i: Human Movement Science. - : Elsevier. - 0167-9457 .- 1872-7646. ; 46, s. 239-250
-
Tidskriftsartikel (refereegranskat)abstract
- Children with unilateral Cerebral Palsy (uCP) experience problems performing tasks requiring the coordinated use of both hands (bimanual coordination; BC). Additionally, some children with uCP display involuntary symmetrical activation of the opposing hand (mirrored movements). Measures, used to investigate therapy-related improvements focus on the functionality of the affected hand during unimanual or bimanual tasks. None however specifically address spatiotemporal integration of both hands. We explored the kinematics of hand movements during a bimanual task to identify parameters of BC. Thirty-seven children (aged 10.9. ±. 2.6. years, 20 male) diagnosed with uCP participated. 3D kinematic motion analysis was performed during the task requiring opening of a box with their affected- (AH) or less-affected hand (LAH), and pressing a button inside with the opposite hand. Temporal and spatial components of data were extracted and related to measures of hand function and level of impairment. Total task duration was correlated with the Jebsen-Taylor Test of Hand Function in both conditions (either hand leading with the lid-opening). Spatial accuracy of the LAH when the box was opened with their AH was correlated with outcomes on the Children's Hand Use Experience Questionnaire. Additionally, we found a subgroup of children displaying non-symmetrical movement interference associated with greater movement overlap when their affected hand opened the box. This subgroup also demonstrated decreased use of the affected hand during bimanual tasks. Further investigation of bimanual interference, which goes beyond small scaled symmetrical mirrored movements, is needed to consider its impact on bimanual task performance following early unilateral brain injury.
|
|
| 13. |
- Rylander, Pär, 1973, et al.
(författare)
-
The specificity versus generality of ball-handling skills – Empirical evidence for a general ball-handling ability
- 2019
-
Ingår i: Human Movement Science. - : Elsevier BV. - 1872-7646 .- 0167-9457. ; 66, s. 477-486
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to investigate if ball-handling skills are specific and uncorrelated (i.e., motor specificity), or if they share an underlying ball-handling ability (i.e., motor generality). To empirically investigate this question, we had a sample of 201 adolescents perform 12 novel ball-handling tasks. Using confirmatory factor analysis, we showed that a model based on the assumptions of the generality perspective was superior to a model based on assumptions of specificity. The general ball-handling factor did significantly influence the performance on all 12 tasks, with factor loadings ranging between 0.39 and 0.79. The results and it's practical implications are discussed in relation to development of sport specific skills.
|
|
| 14. |
- Röijezon, Ulrik, et al.
(författare)
-
Deep and superficial cervical muscles respond differently to unstable motor skill tasks
- 2021
-
Ingår i: Human Movement Science. - : Elsevier. - 0167-9457 .- 1872-7646. ; 80
-
Tidskriftsartikel (refereegranskat)abstract
- Biomechanical modelling and physiological studies suggest that various spinal muscle layers differ in their contribution to spine movement and stiffness. This study aimed to investigate the activation of deep and superficial muscles in stable and unstable task conditions. Nine healthy participants performed a task of controlling a metal ball on a plate fixed to the head in seated position. In unstable tasks, visual feedback was provided by mirrors to move the ball to the centre of the plate by small head movements and maintain the position for 3 s. Task difficulty was adjusted in a stepwise progression of difficulty using five surfaces with materials of decreasing resistance. In the stable condition, the ball was fixed to the plate's centre. EMG was recorded with surface (sternocleidomastoid, anterior scalenes, upper trapezius) and fine-wire electrodes (rectus capitis posterior major, obliquus inferior, multifidus, semispinalis cervicis, splenius capitis). The outcome variable was root mean square (RMS) EMG during the part of the task when the ball was maintained in the centre position. Results revealed greater cervical muscle activity in the unstable than stable conditions (p < 0.001, ηp2 = 0.746). Control of deep and superficial cervical muscles differed (p = 0.003, ηp2 = 0.354). Deep cervical muscle activity was greater with unstable tasks, but did not differ with task difficulty. In contrast, superficial cervical muscle activity increased in a stepwise manner with increasing challenge. These results support the notion that the central nervous system uses different strategies for control of deep versus superficial muscle layers of the cervical spine in association with instability.
|
|
| 15. |
- Sandlund, Jonas, et al.
(författare)
-
Differences in motor variability among individuals performing a standardized short-cycle manual task
- 2017
-
Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457 .- 1872-7646. ; 51, s. 17-26
-
Tidskriftsartikel (refereegranskat)abstract
- Motor variability (MV) has been suggested to be a determinant of the risk for developing musculoskeletal disorders in repetitive work. In this study we examined whether individuals consistently differed in the extent of motor variability when performing a standardized short-cycle manual task. On three separate days, arm kinematics was recorded in 14 healthy subjects performing a pipetting task, transferring liquid from a pick-up tube to eight target tubes with a cycle time of 2.8 s. Cycle-to-cycle standard deviations (SD) of a large selection of shoulder and elbow kinematic variables, were processed using principal component analysis (PCA). Thereafter, between-subjects and between-days (within-subject) variance components were calculated using a random effects model for each of four extracted principal components. The results showed that MV differed consistently between subjects (95% confidence intervals of the between-subjects variances did not include zero) and that subjects differed consistently in MV between days. Thus, our results support the notion that MV may be a consistent personal trait, even though further research is needed to verify whether individuals rank consistently in MV even across tasks. If so, MV may be a candidate determinant of the risk of developing fatigue and musculoskeletal disorders in repetitive occupational work.
|
|
| 16. |
|
|
| 17. |
- Srinivasan, Divya, et al.
(författare)
-
Does the Central Nervous System learn to plan bimanual movements based on its expectation of availability of visual feedback
- 2012
-
Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457 .- 1872-7646. ; 31:6, s. 1409-1424
-
Tidskriftsartikel (refereegranskat)abstract
- The correlation between gaze strategy and kinematics of bimanual movements isassessed using repetitive bimanual object transfers as an experimental paradigm. The hypothesis isthat visual demand in such tasks may be a critical bottleneck determining bimanual coordination.Kinematics and eye-movements were compared before and after practice of this repetitive task.New eye-hand coordination strategies emerged with practice. Also, with practice, a systematicprioritization of the left hand movement to be „primary‟ and the right hand movement to be„secondary‟ emerged. This choice implied that the left hand movement kinematics was similar tounimanual left hand movements, whereas the performance of the right hand task was contingent onsuccessful completion of the primary task. This was revealed by „anticipatory adjustments‟ of theright hand kinematics (Right-hand peak velocity ranged from 100%-70% of the left-hand, and thescaling was dependent on task conditions and the corresponding eye-hand coordination strategiesused). We use this evidence to argue that the CNS, aware of an inherent asymmetry between thetwo hand systems, learns to anticipate the need and availability of visual feedback for successfultask completion, and uses this knowledge to optimize movement coordination - specifically suchthat the right-hand control was modulated to take visual constraints into account.
|
|
| 18. |
- Srinivasan, Divya, et al.
(författare)
-
Effects of concurrent physical and cognitive demands on arm movement kinematics in a repetitive upper-extremity precision task
- 2015
-
Ingår i: Human Movement Science. - : Elsevier. - 0167-9457 .- 1872-7646. ; 42, s. 89-99
-
Tidskriftsartikel (refereegranskat)abstract
- The effect of concurrent physical and cognitive demands on arm motor control is poorly understood. This exploratory study compared movement kinematics in a repetitive high-precision pipetting task with and without additional concurrent cognitive demands in the form of instructions necessary to locate the correct target tube. Thirty-five healthy female subjects performed a standardized pipetting task, transferring liquid repeatedly from one pick-up tube to different target tubes. In the reference condition, lights indicated the target tube in each movement cycle, while the target tube had to be deciphered from a row and column number on a computer screen in the condition with additional cognitive demands. Kinematics of the dominant arm was assessed using the central tendency and variability of the pipette-tip end-point trajectory and joint kinematics properties of the shoulder and elbow. Movements slowed down (lower velocities and higher area under the movement curves) and end point trajectory variability increased in the condition with additional cognitive demands, but there were no changes in the kinematics properties such as joint range of motion, times of acceleration and deceleration (as indicated by the time to peak velocity), average angles, or phase relationships between angle and angular velocity of shoulder or elbow movements between the two conditions. Further, there were also no differences in the size or structure of variability of the shoulder and elbow joint angles, suggesting that subjects could maintain the motor repertoire unaltered in the presence of these specific additional cognitive demands. Further studies should address motor control at other levels of concurrent cognitive demands, and with motor tasks that are less automated than the pipetting task used in the present study, so as to gain an increased understanding of the effect of concurrent cognitive demands for other activities of relevance to daily life.
|
|
| 19. |
- Vinçon, Sabine, et al.
(författare)
-
Ecological validity of the German Bruininks-Oseretsky Test of Motor Proficiency – 2nd Edition
- 2017
-
Ingår i: Human Movement Science. - : Elsevier. - 0167-9457 .- 1872-7646. ; 53, s. 45-54
-
Tidskriftsartikel (refereegranskat)abstract
- The diagnosis of Developmental Coordination Disorder (DCD) is based on poor motor coordination in the absence of other neurological disorders. In order to identify the presence of movement difficulties, a standardised motor assessment is recommended to determine the extent of movement problems which may contribute to deficits in daily task performance. A German version of the Bruininks-Oseretsky Test of Motor Proficiency, Second Edition (German BOT-2) was recently published. This study aimed to determine the ecological validity of the German BOT-2 by considering the relationship between assessment of fundamental motor skills with the BOT-2 and performance of everyday motor activities as evaluated by parents. This study used data obtained from the German BOT-2 standardisation study (n = 1.177). Subtests were compared with theoretically corresponding tasks via parental ratings of overall fine and gross motor abilities and performance in six typical motor activities. Non-parametric Jonckheere Terpstra test was used to identify differences in ordered contrasts. Subtests reflecting ‘Strength’, ‘Running Speed and Agility’, ‘Upper-Limb Coordination’, ‘Balance’, and ‘Fine Motor Precision’ were associated with parental evaluation of gross motor skills (p < 0.001). The subtest ‘Fine Motor Integration’ significantly correlated with parental ratings of females’ fine motor skills. Parental ratings of males’ fine motor skills were associated with three further subtests. Regarding everyday motor activities, the first three fine motor BOT-2 subtests were associated with parent evaluations of drawing, writing and arts and crafts (p < 0.001). Gross motor subtests of ‘Bilateral Coordination’ and ‘Balance’ showed no relationship to bike riding or performance in sports. Subtests of ‘Upper-Limb Coordination’ and ‘Strength’ showed significant correlations with sports, ball games and cycling. The results of this study suggest that the closer the proximity in the nature of the motor skills assessed in the German BOT-2 to daily motor tasks, the stronger the relationship between the clinical test and parental report of everyday performance of their child. The body functions tested in the German BOT-2, and hypothesized to underpin certain skills, were not automatically relevant for specific activities undertaken by German children. Future research should investigate the relationships of the various BOT-2 constructs for diagnosis of DCD.
|
|
| 20. |
- Yang, Junkai, et al.
(författare)
-
A mechanism of timing variability underlying the association between the mean and SD of asynchrony
- 2019
-
Ingår i: Human Movement Science. - : Elsevier. - 0167-9457 .- 1872-7646. ; 67
-
Tidskriftsartikel (refereegranskat)abstract
- Sensorimotor timing behaviors typically exhibit an elusive phenomenon known as the negative asynchrony. When synchronizing movements (e.g. finger taps) with an external sequence (e.g. a metronome), people’s taps precede event onsets by a few tens of milliseconds. We recently reported that asynchrony is less negative in participants with lower asynchrony variability. This indicates an association between negative asynchrony and variability of timing. Here, in 24 metronome-synchronization data sets, we modeled asynchrony series using a sensorimotor synchronization model that accounts for serial dependence of asynchronies. The results showed that the modeling well captured the negative correlation between the mean and SD of asynchrony. The finding suggests that serial dependence in asynchronies is an essential mechanism of timing variability underlying the association between the mean and SD of asynchrony.
|
|
| 21. |
|
|
| 22. |
|
|
| 23. |
- Bendiksen, M., et al.
(författare)
-
Application of the Copenhagen Soccer Test in high-level women players - locomotor activities, physiological response and sprint performance
- 2013
-
Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457. ; 32:6, s. 1430-1442
-
Tidskriftsartikel (refereegranskat)abstract
- We evaluated the physiological response, sprint performance and technical ability in various phases of the Copenhagen Soccer Test for Women (CSTw.) and investigated whether the locomotor activities of the CSTw were comparable to competitive match-play (CM). Physiological measurements and physical/technical assessments were performed during CSTw for eleven Norwegian high-level women soccer players. The activity pattern during CSTw and CM was monitored using the ZXY tracking system. No differences were observed between CSTw and CM with regards to total distance covered (10093 +/- 94 and 9674 +/- 191 m), high intensity running (1278 +/- 67 and 1193 +/- 115 m) or sprinting (422 +/- 55 and 372 +/- 46 m) (p > .05). During CSTw, average HR was 85 +/- 2%HRmax with 35 +/- 2% playing time >90%HRmax. Blood lactate increased (p < .05) from 1.4 +/- 0.3 mM at rest to an average of 4.7 +/- 0.5 mM during CSTw, with no changes during the test. Blood glucose was 5.4 +/- 0.3 mM at rest and remained unaltered during CSTw. Sprint performance (2 x 20 in) decreased (p < .05) by 3% during CSTw (8.19 +/- 0.06-8.47 +/- 0.10 s). In conclusion, the locomotor activities during CSTw were comparable to that of high-level competitive match-play. The physiological demands of the CSTw were high, with no changes in heart rate, blood lactate or technical performance during the test, but a lowered sprint performance towards the end of the test. (C) 2013 Elsevier B.V. All rights reserved.
|
|
| 24. |
- Bradley, P. S., et al.
(författare)
-
Gender differences in match performance characteristics of soccer players competing in the UEFA Champions League
- 2014
-
Ingår i: Human Movement Science. - : Elsevier BV. - 0167-9457. ; 33, s. 159-171
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to examine gender differences in match performance characteristics of elite soccer players. Fifty-four male and fifty-nine female soccer players were tracked during UEFA Champions League matches using a multi-camera system (Amisco, Nice, France). Male players covered more (P<.01) distance than female players in total during a match (Effect Size [ES]: 0.5) and at higher speed thresholds (>15, >18, 18-21, 21-23, 23-25 and >27 km h(-1); ES: 0.7-1.4). Decrements in the second versus first half (P<.01) were only evident in female players for the distance covered in total and at selected speed thresholds (12-15, >12 and >15 km h(-1); ES: 0.6). Male central midfielders covered more (P<.01) total distance during a match than female central midfielders and at selected speed thresholds (15-23 km h(-1); ES: 1.3-2.2). Male full-backs and wide midfielders covered a greater distance (P<.01) than female players in the same positions at higher speed thresholds (>15, 21-23, 23-25, 25-27 and >27 km h(-1); ES: 1.5-3.1). The distance covered during the most intense 5 min period of the match (>15 km h(-1)) was higher (P<.01) in male compared to female players (ES: 1.0) but no distance deficit in the next versus the average 5 min period was observed for either gender (ES: 0.1-0.2). No gender differences were found for technical events such as the number of ball touches, time in possession of the ball or total duels won during both halves and the entire match (ES: 0.1-0.3). However, female players lost the ball more often (P<.05) and displayed lower pass completion rates than male players during both halves and the entire match (ES: 0.5-0.9). The data demonstrate that large gender differences exist for match performance characteristics of players competing at the highest competitive standard of European soccer. Such detailed analyses could be useful for gender-specific training information for optimal preparation. However, more research is warranted to establish gender-specific speed thresholds for elite soccer players. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.
|
|
| 25. |
- Karlsson, Dan, et al.
(författare)
-
On skin movement artefact-resonant frequencies of skin markers attached to the leg
- 1999
-
Ingår i: Human Movement Science. - 0167-9457. ; 18:5, s. 627-635
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, some dynamic effects of the relative motion between the skin and the underlying bone – skin movement artefact – are presented. Two parameters were investigated: (1) the local stiffness of different attachment sites along the leg and (2) the resonant frequencies of wand marker systems. The tangential stiffness was found to vary between 330 and 1900 N/m with the smallest stiffness found in the anterior/posterior direction on the proximal thigh. The highest stiffness measured was in the proximal–distal direction at the knee. The resonant frequencies of wand markers placed on the leg were found to be typically 23–51 Hz, depending on the mass of the marker. The effect of keeping the muscles tensed was also measured. Increased muscle tension provided a more stable base, producing increased stiffness.
|
|
