Biomechanical mechanisms of jumping performance in youth elite female soccer players.

We aimed to determine key biomechanical parameters explaining age-related jumping performance differences in youth elite female soccer players. Multiple biomechanical parameters from countermovement (CMJ) squat (SJ) and drop (DJ) jump testing of elite female soccer players (n = 60) within the same national training centre were analysed across ages 9-11y, 12-14y and 15-19y. Effects of age group and jump type on jump height were found, with the older jumping higher than the younger groups in all jumps (P < 0.05). For DJ, higher reactive strength index was found for older, compared to each younger group (P < 0.001). For CMJ and SJ, peak power was the most decisive characteristic, with significant differences between each group for absolute peak power (P < 0.0001) and body-weight-normalised peak power in CMJ (57 ± 7W/kg, 50 ± 7W/kg, 44.7 ± 5.5W/kg; P < 0.05) and between the older and each younger group in SJ (56.7 ± 7.1W/kg, 48.9 ± 7.1W/kg, 44.6 ± 6W/kg; P < 0.01). Age-related differences in jumping performance in youth elite female soccer players appear to be due to power production during standing jumps and by the ability to jump with shorter ground contact times during reactive jumps.

Switch hands! Mapping proactive and reactive cognitive control across the life span.

We investigated the effects of age on proactive and reactive cognitive control in a large population sample of 809 individuals, ranging in age between 5 and 97 years. For that purpose, we used an anticue paradigm, which required a consistent remapping of cue location and response hand: Left-sided cues required right-hand responses and vice versa. After a random preparation interval of 100-850 ms, these anticues were followed by a target stimulus, which prompted a response with the index or middle finger of 1 of 2 hands. A neutral control condition involved uninformative cues, indicating all 4 possible response locations. The primary outcome measure was the difference between neutral and anticue reaction time (RT). Negative values indicated RT costs of the anticue, relative to the neutral condition, reflecting reactive cognitive control. Positive values indicated RT benefits, reflecting proactive cognitive control. Results were twofold. First, the switch from RT costs to benefits took place at longer preparation intervals in the youngest and oldest age groups than in the intermediate age groups. Second, irrespective of preparation interval, anticue performance followed an inverted U-shaped trajectory as a function of age, with a relatively steep improvement during childhood and adolescence, relative stability between 26 and 60 years, and a slightly accelerating decline into old age. Both patterns of results suggest an age-related transition from a primarily reactive, to a primarily proactive mode of cognitive control in early life and back again from a primarily proactive, to a primarily reactive mode of control in later life. (PsycINFO Database Record

Dynamic testing of learning potential in adults with cognitive impairments: A systematic review of methodology and predictive value.

Dynamic testing includes procedures that examine the effects of brief training on test performance where pre- to post-training change reflects patients' learning potential. The objective of this systematic review was to provide clinicians and researchers insight into the concept and methodology of dynamic testing and to explore its predictive validity in adult patients with cognitive impairments. The following electronic databases were searched: PubMed, PsychINFO, and Embase/Medline. Of 1141 potentially relevant articles, 24 studies met the inclusion criteria. The mean methodological quality score was 4.6 of 8. Eleven different dynamic tests were used. The majority of studies used dynamic versions of the Wisconsin Card Sorting Test. The training mostly consisted of a combination of performance feedback, reinforcement, expanded instruction, or strategy training. Learning potential was quantified using numerical (post-test score, difference score, gain score, regression residuals) and categorical (groups) indices. In five of six longitudinal studies, learning potential significantly predicted rehabilitation outcome. Three of four studies supported the added value of dynamic testing over conventional testing in predicting rehabilitation outcome. This review provides preliminary support that dynamic tests can provide a valuable addition to conventional tests to assess patients' abilities. Although promising, there was a large variability in methods used for dynamic testing and, therefore, it remains unclear which dynamic testing methods are most appropriate for patients with cognitive impairments. More research is warranted to further evaluate and refine dynamic testing methodology and to further elucidate its predictive validity concerning rehabilitation outcomes relative to other cognitive and functional status indices.

Switch hands! Mapping temporal dynamics of proactive manual control with anticues.

This study uses a novel behavioral paradigm-the anticue task-to investigate the temporal dynamics of proactive control aimed at the resolution of response conflict in the manual motor system. The anticue task is a 4-choice reaction time (RT) task, with left and right anticues indicating mirror-symmetrical response hands. In particular, anticues require participants to prepare fingers on the hand opposite to the side of the cue (counter-corresponding mapping), which contrasts with the more standard procues that prompt participants to prepare fingers on the hand spatially in line with the cue (corresponding mapping). In Experiment 1, we examined the effects of anticues and procues as a function of cue-target interval (range: 100-850ms). Results showed that procues produced RT benefits (relative to neutral cues), which increased with longer cue-target intervals. Anticues, however, produced RT costs with short cue-target intervals and RT benefits with longer cue-target intervals. These findings support the view that anticues are mediated by a time-consuming, proactive control process that, using inhibition and activation, redirects the initial but wrong activation of the ipsilateral hand to the correct contralateral hand. In Experiment 2, we used a simple detection response to test, and reject, an alternative (attentional) account of these findings. Theoretical and practical implications are discussed in the context of dual-route models of response selection, the activation-suppression model, and related experimental protocols such as antisaccade, Simon, Stroop, Eriksen flanker, and task switching paradigms.

The closer the better: Hand proximity dynamically affects letter recognition accuracy.

A growing literature has suggested that processing of visual information presented near the hands is facilitated. In this study, we investigated whether the near-hands superiority effect also occurs with the hands moving. In two experiments, participants performed a cyclical bimanual movement task requiring concurrent visual identification of briefly presented letters. For both the static and dynamic hand conditions, the results showed improved letter recognition performance with the hands closer to the stimuli. The finding that the encoding advantage for near-hand stimuli also occurred with the hands moving suggests that the effect is regulated in real time, in accordance with the concept of a bimodal neural system that dynamically updates hand position in external space.

Practical research-based guidance for motor imagery practice in neurorehabilitation.

PURPOSE: The purpose of this appraisal is to offer guidance to clinicians on applying motor imagery in neurorehabilitation and provide guidance to support this process. METHOD: We used evidence from a variety of fields as well as clinical experience with motor imagery to develop guidance for employing motor imagery during neurorehabilitation. RESULTS: Motor imagery is a relatively new intervention for neurorehabilitation supported by evidence from areas such as cognitive neuroscience and sports psychology. Motor imagery has become a very popular intervention modality for clinicians but there is insufficient information available on how to administer it in clinical practice and make deliberate decisions during its application. CONCLUSIONS: We provide evidence-based guidance for employing motor imagery in neurorehabilitation and use the principles of motor learning as the framework for clinical application.

Spared within-hands but impaired between-hands response preparation in aging.

OBJECTIVES: Older people can use advance information to prepare a subset of finger responses. It is debated, however, whether aging affects the preparation of finger responses on two hands (between-hands preparation) more strongly than the preparation of finger responses on one hand (within-hands preparation). The present study examined the role of temporal uncertainty in this issue. METHODS: We asked a group of young and older participants to perform a finger-cuing task with four preparation intervals (2, 3, 4, and 5 s), presented either separately in distinct blocks of trials (fixed design: no temporal uncertainty) or randomly intermixed across trials (mixed design: temporal uncertainty). RESULTS: Reaction time and error rates revealed age equivalence for within-hands preparation but an age-related difference for between-hands preparation, regardless of how the preparation intervals were presented. DISCUSSION: These findings demonstrate a robust, structural difference in the maximal preparation benefit that older adults can achieve when preparing two fingers on two hands but not on one hand. These outcomes are discussed in terms of several theories of cognitive aging.

Agreement between two different scoring procedures for goal attainment scaling is low.

OBJECTIVE: To investigate the agreement between a patient's therapist and an independent assessor in scoring goal attainment by a patient. METHODS: Data were obtained on hospital patients with neurological disorders participating in a randomized trial. The patients' therapists set 2-4 goals using a goal attainment scaling method. Six weeks later attainment was scored by: (i) the treating therapists; and (ii) an independent assessor unfamiliar with the patient, using a semi-structured interview method with direct assessment as appropriate. RESULTS: A total of 112 goals in 29 neurological patients were used. The intraclass correlation coefficient (ICC(A,k) = 0.478) and limits of agreement (­1.52 ± 24.54) showed poor agreement between the two scoring procedures. There was no systematic bias. CONCLUSION: The agreement between the patients' therapists scoring the goals and the independent assessor was low, signifying a large difference between the two scoring procedures. Efforts should be made to improve the reproducibility of goal attainment scaling before it is to be used as an outcome measure in blinded randomized controlled trials.

Writing SMART rehabilitation goals and achieving goal attainment scaling: a practical guide.

OBJECTIVE: To describe a practical method of setting personalized but specific goals in rehabilitation that also facilitates the use of goal attainment scaling. BACKGROUND: Rehabilitation is a complex intervention requiring coordinated actions by a team, a process that depends upon setting interdisciplinary goals that are specific, clear and personal to the patient. Goal setting can take much time and still be vague. A practical and standardized method is needed for being specific. METHOD: A novel approach to writing specific, measurable, achievable, realistic/ relevant and timed (SMART) goals is developed here. Each goal can be built up by using up to four parts: the target activity, the support needed, quantification of performance and the time period to achieve the desired state. This method can be employed as part of goal attainment scaling and the other levels can be easily and quickly formulated by adding, deleting and/or changing one or more of the (sub)parts. DISCUSSION: The success of goal setting and goal attainment scaling depends on the formulation of the goals. The method described here is a useful tool to standardize the writing of goals in rehabilitation. It saves time and simplifies the construction of goals that are sufficiently specific to be measurable.

Mental techniques during manual stretching in spasticity--a pilot randomized controlled trial.

OBJECTIVE: To evaluate the feasibility and effects of using motor imagery during therapeutic stretching in individuals with spasticity. DESIGN: Randomized single-blind controlled pilot trial. SETTING: Chronic day care unit, neurological rehabilitation unit and in the community. SUBJECTS: Eleven individuals with spasticity in the arm requiring stretching as part of their normal routine. INTERVENTIONS: In addition to their normal stretching routine, subjects in the experimental group received motor imagery during their stretches (n = 6). The control group received progressive muscle relaxation during their stretches (n = 5). The dose varied between 8 and 56 sessions over eight weeks. MAIN MEASURES: Resistance to passive movement, measured with a torque transducer, passive range of movement, measured with an electro-goniometer, Modified Ashworth Scale (MAS) and level of discomfort during the MAS were assessed at baseline and after eight weeks by an independent assessor. These measures were recorded before and after a stretch intervention on both assessments. RESULTS: Participants, therapists and carers tolerated the techniques well. Compliance was variable and adherence was good. Mixed ANOVA showed no difference over time and no difference between the motor imagery and progressive muscle relaxation group on the primary and secondary outcome measures (P>0.05). CONCLUSIONS: It is feasible to use motor imagery during therapeutic stretching. Statistical power was low due to the large variability in the population and the small sample size. Post-hoc sample size calculation suggests that future studies of this subject should include at least 54 participants per group. Further research is warranted.