The present study examined differences in visual search and locomotor behavior among a group of skilled 10–12 year-old football players. The participants watched video clips of a 4-to-4 position game, presented on a large screen. The participants were asked to take part in the game by choosing the best position for the reception of the ball passed by one of the players in the clip. Participants’ visual search and locomotor behavior were collected continuously throughout the presentation of the clip. A within-group comparison was made based upon the participants’ interception score, i.e., more at the correct position. The findings show that the high-score group looked more to the ball area, while the players in the low-score group concentrated on the receiving player and on the hips/upper-body region of the passing player. The players in the high-score group covered a significantly greater distance compared to the low-score group. It was concluded that differences in visual search and locomotion behavior can be used as indicators for identifying talented junior football players.
DOCUMENT
In this thesis we analyzed clinimetric measurement properties of physical fitness tests in wheelchair-using youth with SB. Furthermore, the amount of physical behavior in wheelchair-using youth with SB was quantified and associations with age, gender, VO2peak and Hoffer classification were evaluated. Finally, we described the factors associated with physical behavior in youth with SB and youth with physical disabilities, after which the evidence of interventions to improve physical behavior in youth with physical disabilities was analyzed. This last chapter presents the theoretical and clinical implications. At the end, methodological considerations and directions for further research will be discussed after which the overall conclusion is presented.
DOCUMENT
BACKGROUND: Hospital stays are associated with high levels of sedentary behavior and physical inactivity. To objectively investigate physical behavior of hospitalized patients, these is a need for valid measurement instruments. The aim of this study was to assess the criterion validity of three accelerometers to measure lying, sitting, standing and walking. METHODS: This cross-sectional study was performed in a university hospital. Participants carried out several mobility tasks according to a structured protocol while wearing three accelerometers (ActiGraph GT9X Link, Activ8 Professional and Dynaport MoveMonitor). The participants were guided through the protocol by a test leader and were recorded on video to serve as reference. Sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV) were determined for the categories lying, sitting, standing and walking. RESULTS: In total 12 subjects were included with a mean age of 49.5 (SD 21.5) years and a mean body mass index of 23.8 kg/m2 (SD 2.4). The ActiGraph GT9X Link showed an excellent sensitivity (90%) and PPV (98%) for walking, but a poor sensitivity for sitting and standing (57% and 53%), and a poor PPV (43%) for sitting. The Activ8 Professional showed an excellent sensitivity for sitting and walking (95% and 93%), excellent PPV (98%) for walking, but no sensitivity (0%) and PPV (0%) for lying. The Dynaport MoveMonitor showed an excellent sensitivity for sitting (94%), excellent PPV for lying and walking (100% and 99%), but a poor sensitivity (13%) and PPV (19%) for standing. CONCLUSIONS: The validity outcomes for the categories lying, sitting, standing and walking vary between the investigated accelerometers. All three accelerometers scored good to excellent in identifying walking. None of the accelerometers were able to identify all categories validly.
DOCUMENT
Background The plantar intrinsic foot muscles (PIFMs) have a role in dynamic functions, such as balance and propulsion, which are vital to walking. These muscles atrophy in older adults and therefore this population, which is at high risk to falling, may benefit from strengthening these muscles in order to improve or retain their gait performance. Therefore, the aim was to provide insight in the evidence for the effect of interventions anticipated to improve PIFM strength on dynamic balance control and foot function during gait in adults. Methods A systematic literature search was performed in five electronic databases. The eligibility of peer-reviewed papers, published between January 1, 2010 and July 8, 2020, reporting controlled trials and pre-post interventional studies was assessed by two reviewers independently. Results from moderate- and high-quality studies were extracted for data synthesis by summarizing the standardized mean differences (SMD). The GRADE approach was used to assess the certainty of evidence. Results Screening of 9199 records resulted in the inclusion of 11 articles of which five were included for data synthesis. Included studies were mainly performed in younger populations. Low-certainty evidence revealed the beneficial effect of PIFM strengthening exercises on vertical ground reaction force (SMD: − 0.31-0.37). Very low-certainty evidence showed that PIFM strength training improved the performance on dynamic balance testing (SMD: 0.41–1.43). There was no evidence for the effect of PIFM strengthening exercises on medial longitudinal foot arch kinematics. Conclusions This review revealed at best low-certainty evidence that PIFM strengthening exercises improve foot function during gait and very low-certainty evidence for its favorable effect on dynamic balance control. There is a need for high-quality studies that aim to investigate the effect of functional PIFM strengthening exercises in large samples of older adults. The outcome measures should be related to both fall risk and the role of the PIFMs such as propulsive forces and balance during locomotion in addition to PIFM strength measures.
MULTIFILE
Introduction Negative pain-related cognitions are associated with persistence of low-back pain (LBP), but the mechanism underlying this association is not well understood. We propose that negative pain-related cognitions determine how threatening a motor task will be perceived, which in turn will affect how lumbar movements are performed, possibly with negative long-term effects on pain. Objective To assess the effect of postural threat on lumbar movement patterns in people with and without LBP, and to investigate whether this effect is associated with task-specific pain-related cognitions. Methods 30 back-healthy participants and 30 participants with LBP performed consecutive two trials of a seated repetitive reaching movement (45 times). During the first trial participants were threatened with mechanical perturbations, during the second trial participants were informed that the trial would be unperturbed. Movement patterns were characterized by temporal variability (CyclSD), local dynamic stability (LDE) and spatial variability (meanSD) of the relative lumbar Euler angles. Pain-related cognition was assessed with the task-specific ‘Expected Back Strain’-scale (EBS). A three-way mixed Manova was used to assess the effect of Threat, Group (LBP vs control) and EBS (above vs below median) on lumbar movement patterns. Results We found a main effect of threat on lumbar movement patterns. In the threat-condition, participants showed increased variability (MeanSDflexion-extension, p<0.000, η2 = 0.26; CyclSD, p = 0.003, η2 = 0.14) and decreased stability (LDE, p = 0.004, η2 = 0.14), indicating large effects of postural threat. Conclusion Postural threat increased variability and decreased stability of lumbar movements, regardless of group or EBS. These results suggest that perceived postural threat may underlie changes in motor behavior in patients with LBP. Since LBP is likely to impose such a threat, this could be a driver of changes in motor behavior in patients with LBP, as also supported by the higher spatial variability in the group with LBP and higher EBS in the reference condition.
LINK
This thesis aims to develop and validate a comprehensive and adaptable activity monitoring system that quantifies physical behaviours in children with and without developmental disabilities, including those utilizing assistive devices. This system seeks to overcome the current limitations in the accuracy and feasibility of existing monitoring devices by providing robust measurements in real-world settings.
MULTIFILE
Talloze studies tonen aan dat een fysiek actieve leefstijl bloeddruk, cholesterol en gewicht verlaagt, botten en spieren versterkt en het risico van hart- en vaatziekten, darmkanker en diabetes type II vermindert. Bewegen kan dus worden gezien als een medicijn wat voor iedereen toegankelijk is.
DOCUMENT
A commentary on: Older adults can improve compensatory stepping with repeated postural perturbations by Dijkstra,B.W., Horak,F.B., Kamsma,Y.P.T., and Peterson,D.S.(2015).Front.AgingNeurosci. 7:201. doi:10.3389/fnagi.2015.00201. In sum, the results of Dijkstra etal. (2015) are of importance and significance for the field of falls prevention and stability control in aging. In particular, the work highlights the importance of multidirectional step or perturbation training, due to a lack of transfer across tasks. Whether this would hold for multidirectional gait perturbations is unclear, due to the influence of forward velocity during walking. Future work should explore different types, intensities and frequencies of perturbations in order to determine the most effective strategy for improving dynamic stability control in healthy older adults and inpatients with declined locomotor performance and increased falls risk. Finally, as Dijkstra etal. (2015) and previous studies found floor effects in the adaptation of young participants, further attempts should be made to appropriately scale perturbations to participant or groupability, in order to reliably compare adaptation across different groups.
DOCUMENT
Toenemende prevalentie van overgewicht en obesitas onder jeugd wordt, in ieder geval ten dele, veroorzaakt door te weinig fysieke activiteit. Omdat ieder kind een groot deel van zijn of haar jeugdige leven op school doorbrengt kunnen scholen een centrale rol spelen in het tegengaan van deze bewegingsarmoede. Het meest voor de hand liggende schoolvak lijkt hierbij de lichamelijke opvoeding1 (LO) te zijn. De belangrijkste doelstelling van het schoolvak LO is immers om leerlingen dusdanig te motiveren en enthousiast te maken voor sport en bewegen zodat dit uiteindelijk resulteert in een actieve leefstijl, zowel buiten school als in het verdere leven. Daarnaast is LO tevens het enige verplichte schoolvak waar fysieke activiteit een centrale plek inneemt; de les zelf is in potentie ook een structurele bron van fysieke activiteit. Globaal gezien kan LO dus op een indirecte en een directe manier bijdragen aan de fysieke activiteit van leerlingen, een tweedeling die werd geïntroduceerd in hoofdstuk 1. Waar echter tot op heden onduidelijkheid over bestaat, zeker wat betreft de Nederlandse situatie, is hoe groot de bijdrage van de LO aan dagelijkse fysieke activiteit feitelijk is. De vraag die daarom centraal staat in dit proefschrift is in hoeverre het vak LO, zoals dat op dit moment gegeven wordt op basis- en voortgezet onderwijs, een bijdrage levert aan de fysieke activiteit van kinderen en adolescenten, zowel direct (de les als bron van fysieke activiteit), als indirect (motivatie voor een actieve leefstijl). Voor de beantwoording van deze vraag zijn een aantal studies uitgevoerd. Allereerst is in hoofdstuk 2 door middel van een literatuurstudie onderzocht in hoeverre interventies met een LO-component effectief zijn in het stimuleren van fysieke activiteit. Hieruit blijkt dat er alleen overtuigend bewijs bestaat voor een directe bijdrage van de les LO aan de fysieke activiteit van kinderen en adolescenten. Oftewel, in de les LO zelf wordt er matig-tot-intensief bewogen. De effecten van interventies met een LO component op de fysieke activiteit buiten school of in het latere leven zijn minder overtuigend of zelfs afwezig. In hoofdstuk 3 wordt een cross-sectionele studie beschreven waarin middels het combineren van gegevens vanuit een hartslag-versnellingsmeter met de gegevens uit een activiteitendagboek voor het eerst inzicht verkregen wordt in de daadwerkelijke bijdrage van een reguliere les LO (naast andere fysieke activiteiten zoals fietsen) aan de totale dagelijkse fysieke activiteit van middelbare scholieren. De resultaten wijzen uit dat 17% van de totale hoeveelheid beweging onder schooltijd zijn oorsprong vindt in de lessen LO en dat op dagen dat een leerling een les LO heeft, deze les verantwoordelijk is voor ongeveer 30% van de totale fysieke activiteit op die dag. Opvallend is daarnaast dat 15% van de totale fysieke activiteit op een weekdag zijn oorsprong vindt in het actief transport naar school, voornamelijk fietsen. Hoofdstuk 4 beschrijft een studie waarin de focus ligt op de intensiteit van lessen LO in het voortgezet onderwijs (VO) en het basisonderwijs (BO). Tevens is gekeken naar factoren die de intensiteit van een les beïnvloeden. De resultaten wijzen uit dat 47% en 40% van een les LO op respectievelijk het VO en het BO voldoet aan de intensiteit van bewegen zoals omschreven in de Nederlandse Norm voor Gezond Bewegen (matig-tot-intensief fysiek actief). Dit komt overeen met ongeveer een derde van de dagelijks aanbevolen hoeveelheid beweging voor deze doelgroep. Opvallend is dat op het VO jongens significant actiever zijn tijdens de lessen LO dan meisjes. Dit verschil blijkt zijn oorsprong te hebben in lessen waarin competitieve spelvormen (basketbal, voetbal etc.) centraal staan. Mogelijkerwijs verhindert de dominantie van jongens tijdens spelvormen dat meisjes in een les even actief kunnen zijn als jongens. Dit is een serieuze beperking van de mate waarin een les LO kan bijdragen aan het totale beweeggedrag van meisjes, gezien het feit dat ongeveer 60% van het Nederlandse LO curriculum uit (veelal competitieve) spelvormen bestaat.
DOCUMENT
Introduction Physical activity is suggested to be important for low back pain (LBP) but a major problem is the limited validity of the measurement of physical activities, which is usually based on questionnaires. Physical fitness can be viewed as a more objective measurement and our question was how physical activity based on self-reports and objective measured levels of physical fitness were associated with LBP. Materials and methods We analyzed cross-sectional data of 1,723 police employees. Physical activity was assessed by questionnaire (SQUASH) measuring type of activity, intensity, and time spent on these activities. Physical fitness was based on muscular dynamic endurance capacity and peak oxygen uptake (VO2 peak). Severe LBP, interfering with functioning, was defined by pain ratings C4 on a scale of 0–10. Results Higher levels of physical fitness, both muscularand aerobic, were associated with less LBP (OR: 0.54; 95%CI: 0.34–0.86, respectively, 0.59: 95%CI: 0.35–0.99). For self-reported physical activity, both a low and a high level of the total physical activity pattern were associated with an increase of LBP (OR: 1.52; 95%CI: 1.00–2.31, respectively, 1.60; 95%CI: 1.05–2.44). Conclusion These findings suggest that physical activity of an intensity that improves physical fitness may be important in the prevention of LBP
DOCUMENT
