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Adolescents who enjoy physical education (PE) classes are more likely to be active during out-of-school hours. Similarly, achievement goal theory suggests that task-oriented motivation is associated with higher levels of reported fun during PE classes. In contrast, ego-oriented motivation has been related to boredom in class, but some self-perceptions (e.g., self-esteem or motoric self-efficacy) may modify this relationship and are important for physical activity. Our aim in this paper was to analyze the relationships between motivational orientation and fun and boredom in PE classes by assessing the mediating effects of self-esteem and self-efficacy. We surveyed 478 teenagers between 13 and 18 years of age (M = 14.57; SD = 1.15) with the Task and Ego Orientation in Sport Questionnaire (TEOSQ), the Rosenberg Self-Esteem Scale (RSE), the Motor Self-Efficacy Scale (MSES), and the Intrinsic Satisfaction in Sport Scale (SSI-EF). We used a structural equation model to evaluate relationships between these variables of interest. We found a positive relationship between ego orientation and boredom and between task orientation and fun; and we found a negative relationship between task orientation and boredom in PE classes. Importantly, we observed indirect effects from self-esteem and motoric self-efficacy in the relationships between motivational orientation and boredom and fun in PE. These results highlight the importance of students' motivational orientations in PE classes and illustrate that self-perception of self-esteem and motoric self-efficacy can mediate these relationships. [ABSTRACT FROM AUTHOR]

Beliefs about memory play a role in older adults' concerns about aging and can influence their performance on memory tasks. Visual analog scales can capture beliefs about how aging affects memory in general (the General Beliefs About Memory Instrument [GBMI]) and one's own memory (the Personal Beliefs About Memory Instrument [PBMI]). Data were combined across four cross-sectional studies of adults who had completed the two measures, contrasting traditional paper-and-pencil versions of the questionnaires with newer computerized versions that use a computer mouse for visual analog scaling. This scaling method is easy to use and automates scoring of graphic rating scale responses. Adults of all ages produced GBMI responses reflecting their belief that memory declines with advancing age. Older adults' PBMI responses indicated that they perceived their memory ability more negatively than those of young adults and middle-aged adults. Adults of all ages were able to use the computerized questionnaires without difficulty, making these measures suitable for use in adult developmental research. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the technical-tactical performance profile of the serve for various age groups and categories of competition in men's volleyball. The sample comprised 13,262 serves performed by 986 players in 299 sets observed in various categories of competition (U-14, U-16, U-19, national senior, and international senior). An observational design was used. The variables studied were category of competition, type of execution, and serve performance. The results showed that for higher age groups (senior categories), there were significantly fewer jump serves and poorer serve performance, regardless of players' maturity and training development. The use of the jump serves increased the serve risk while attempting to hinder the organization of the opponent attack. This paper discusses the serve evolution and the implications on the training process at the different age groups in men's volleyball. [ABSTRACT FROM AUTHOR]

In the selection of young athletes, earlier-born adolescents often leverage their temporary biological advantage over their later-born peers from the same cohort, giving rise to the phenomenon known as the Relative Age Effect (RAE). In this study, we delved into the complexities of the RAE in soccer by reviewing 563 independent research samples across 90 articles. Our analysis showed that age period and performance level are pivotal factors influencing the magnitude of the RAE. The adolescent age period emerged as a significant RAE determinant, showcasing the highest effect size magnitudes in our findings. Among athletes of different performance levels, adult European soccer players have been extensively studied, and they have exhibited the most pronounced RAE magnitudes. Intriguingly, our findings reveal another compelling trend: the frequency of players born early versus late in the eligible birth year escalated as player performance levels increased, particularly during adolescence. Coaches and players appear to capitalize unconsciously on this maturational advantage, though this strategy wanes post-adolescence. While there are currently no penalties for this team selection practice, our findings stress the need for coaches to comprehend the ramifications of selecting athletes with an age bias We offer insights into RAE complexities, highlight the synergy of age and performance in these transitory advantages, and advance arguments for more fairly selecting and developing youth athletes. [ABSTRACT FROM AUTHOR]

In overhead shooting athletes may have increased activity of the upper trapezius and inhibition of other shoulder muscles active during upper extremity elevation. In this study, we aimed to increase target retention and shoulder proprioception sense accuracy by taping in a way that would activate the lower trapezius muscle in elite adolescent archers. Our participants were 43 elite young athletes, aged 11–14 years, from the Archers Foundation Sports Club. We gathered athletes' sociodemographic information (age, height, weight, gender, the time they were engaged in archery, and other sports they were involved in), and we assessed their posture via the New York Posture Scale (NYPS) before taping. We evaluated them for the presence of scapular asymmetry using the Lateral Scapular Slide Test (LSST) and assessed their proprioception with the active displacement test and their target-reaching performances with the Archery Shooting Score (ASS). Since testing and scoring with the ASS is different for 11–12 and 13–14 age groups, we divided this sample into two different age groups for all analyses. There were significant changes in ASS and proprioception in both age groups, with medium to large effect sizes. There were between intragroup pre- and post-taping changes in classification according to the presence of scapular asymmetry, and there were significant changes in the archery shooting score and proprioception in both groups, with medium to large effect sizes (p < 0.05). Thus, taping applied to the lower part of the trapezius had a large to medium effect on proprioception and shooting accuracy improvement in these young archers. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic forced governments to implement measures that disrupted the daily routines of many families worldwide. We studied how the COVID-19 lockdown affected children's routines in Portugal (PT), Brazil (BR), and Italy (IT) to determine if children's age and country impacted their physical activity (PA) and sedentary time. We launched an anonymous online survey to assess how 3–12 years old children adjusted their daily routines to this situation. Parents reported the times each child was engaged in different activities throughout the day, and we used these data to calculate separately overall sedentary and physical activity time. We conducted separate analyses of variance for age and country on the percentage of time spent in the different activities. Results, based on the data from 3045 children in these three countries (PT n = 2044; BR n = 836; IT n = 165), showed that, during lockdown, most children spent most of their awake daily hours in sedentary activities. There was a clear age effect on the way their routines were organized. Percentages of time spent in intellectual activity, playful screen activity, and overall sedentary time were greater in the older age groups, whereas percentages of time spent in play (with and without PA) and in overall PA were greater in the younger groups. We found a main effect of country for all variables except play without PA. The country effect was mainly due to the difference between the routines in BR when compared to PT and IT. Values of playful screen time and overall sedentary activity were higher in BR than in the two European countries. Conversely, values for play with PA, PA, and overall PA (except in the older group) were lower in BR. Patterns of time spent in these activities were similar in IT and PT, but PA and overall PA times were higher in the two younger age groups in IT. In summary, percentage of PA time of confined children was low and decreased with age across all three countries and was particularly low for children in BR relative to those in PT and IT. [ABSTRACT FROM AUTHOR]

The present study explores whether SVD affects bimanual coordination, which is easier to detect than by conventional, MRI-based methods. We tested nine severe SVD patients, eight non-severe (i.e., moderate or mild) SVD patients, eleven healthy age-matched controls, and eight young adults. They were grouped according to Fazekas scale and by age. Participants performed horizontal line drawings with both hands simultaneously on two pen tablets. The movements consisted of rhythmic patterns where participants used both hands to draw horizontal lines in anti-phase on two pen tablets. Each participant underwent a series of neuropsychiatric assessments. Results showed that SVD patients exhibited in each hand smaller horizontal movement amplitudes with variability larger compared to the healthy age-matched controls. Only movement amplitudes appeared to decrease significantly with severity of SVD. Interestingly, we found no relevant differences between the age-matched, elderly controls and the young controls. Therefore, this effect appeared indicative of SVD. The variability of the lines orthogonal to the horizontal lines of the left, non-dominant hand differed only between the severe SVD group and the other groups. Furthermore, partial correlations demonstrated that the mean horizontal movement amplitude of the left hand was positively associated with the clock drawing test score, and the inter-manual asynchrony of the horizontal movements was positively associated with the Trail Making Test-B time. These results indicated that SVD patients show poor bimanual coordination, as reflected by spatial features such as movement amplitudes and variabilities, and abnormal bimanual coordination was associated with executive dysfunction. [ABSTRACT FROM AUTHOR]

An adaptive response to unexpected perturbations requires near-term and long-term adjustments over time. We used multifractal analysis to test how nonlinear interactions across timescales might support an adaptive response following an unpredictable perturbation. We reanalyzed torque data from 44 young and 24 older adults who performed a single-leg squat task challenged by an unexpected mechanical perturbation and a secondary visual-cognitive task. We report three findings: (a) multifractal nonlinearity interacted with pre-perturbation torque production and task error to presage greater pre-voluntary feedforward increases and greater voluntary reductions, respectively, in post-perturbation task error; (b) multifractal nonlinearity presaged relatively smaller task error than standard deviations of both pre-perturbation torques and pre-perturbation task error; and (c) increased task demand (e.g., age-related changes in dexterity and dual-task settings) led to multifractal nonlinearity presaging reduced task error. All these results were consistent with our expectations, except that a pre-perturbation knee torque-dependent increase in post-perturbation task error appeared later for older than for younger participants. This correlational multifractal modeling offered theoretical clarity on the possible roles of nonlinear interactions across timescales, moderating both feedforward and feedback processes, and presaging greater stability when the standard deviation is relatively large and task demands are strong. Thus, multifractal nonlinearity usefully describes movement variability even when paired with classical descriptors like the standard deviation. We discuss potential insights from these findings for understanding suprapostural dexterity and developing rehabilitative interventions. [ABSTRACT FROM AUTHOR]

As predictive motor control is an important index of neuromotor development and maturation, we developed two touchscreen tablet-based tests of this function. Our aim was to investigate the reliability and validity of both a rapid manual interception test and a pursuit tracking test, using a sample of 124 children (62 boys and 62 girls) from two age groups (7-8-year-oldss and 9–10-year-olds). Participants performed both tablet tests with a stylus (sample rate 100 Hz) with both a visible and a temporarily invisible moving target. Confirmatory factor analyses and omega coefficients showed that both tests were univariate methods that provided a reliable assessment of the latent factor related to predictive visuomotor control. As would be expected, compared to younger children, older children performed better on both manual interception and pursuit tracking. The correlations between the latent factors of the two tests at 95% confidence intervals (−.276, −.608) suggested shared variance. Thus, the touchscreen-tablet based tests of rapid manual interception and manual pursuit tracking appear psychometrically suitable for assessing the neuromotor ability of predictive control in 7-10-year-old children. [ABSTRACT FROM AUTHOR]

Harmonious voluntary movements require efficiency in their planning and execution. Throughout middle childhood structural changes in the central nervous and musculoskeletal systems influence these processes and resultant motor behavior. In this study, we evaluated the characteristics of the motor planning and executing of aiming movements directed at targets located in different positions in space in children aged 7, 9, and 11 years. We divided 43 right-handed children, into three age groups and instructed them to perform aiming movements directed at targets using a stylus on a digital tablet. The children performed the movement with their dominant upper limbs from a starting point towards targets positioned ipsilaterally or contralaterally to this dominant limb. We analyzed temporal and spatial variables of motor performance. Younger (7-year-old) children made more errors in the initial movement direction and more frequently corrected their movements during task execution when compared to 9- and 11-year-old children who did not differ from each other. All age groups were similar in movement accuracy and precision. Movements toward contralateral targets were slower and more accurate than movements toward ipsilateral targets for all groups. These results show that performing aiming movements develop with the onset of middle childhood. [ABSTRACT FROM AUTHOR]

A large body of literature has addressed processes underlying human perception, with some assertions that children do not perceive space or colors in the same way as adults. Since children express themselves easily and acquire knowledge through graphic symbols, when determining psycho-motor maturity and perceptions of a preschool aged children, observers must evaluate their use of non-verbal graphics. Thus, we used young children's drawings to examine their use of color and spatial perception, as well as to identify differences between children in rural and urban communities. Of 94 participants from rural and urban communities, 46 were kindergarten aged (5.5–6.5 years), and 48 were preschool aged (4.5–5.5 years). Comparing children from urban and rural areas, there were significant differences in their perception of different colors and spatial relations. Motor abilities were significantly different between children of different ages and gender. We argue that the applied assessment methods, such as children's drawings, could be a basis for measuring effective learning and practicing of children's abilities as expressed in the classroom, and that tools may be useful for creating individualized educational plans and programs for developing children's skills through play. [ABSTRACT FROM AUTHOR]

Executive functions (EFs) are higher-level cognitive functions that help keep an individual's goal-oriented thoughts and actions aligned. While many studies have shown the importance of EFs in sport, a limitation in this literature is that female participants have been underrepresented. In this mixed-longitudinal study, we examined the development of EFs in a cohort of high performing female athletes. We collected data over five seasons in a large sample of 175 female soccer players (aged 12–29 years old) from the U14 - senior age groups of a professional German soccer club. Players undertook a large battery of cognitive tasks aimed at measuring higher-level cognitive functioning: a sustained attention task, a stop-signal task, a Go-No-go test, an N-Back Test, and both a 180°- and 360°-multiple-object tracking task. We used linear and non-linear mixed effect regressions to examine the relationship between age and EFs. Second order polynomial curves explained many of these relationships between age and EFs compared to their linear relationships. Negatively accelerated curves reveal that these players' cognitive abilities mainly developed before players reached early adulthood, with a performance plateau evident at around 21 years of age. Age explained low to moderate proportions of the variance in EFs (<1–50%), while cognitive development across playing positions was not a strong contributor to this variance (M = 2.1, SD = 2.1%). We concluded that age has a negatively accelerated relationship with EFs in female soccer players that does not differ between playing positions. These data support the idea that athletes require only a reasonable level of EF ability to perform at the highest level of their sport. Our research raises new questions regarding the validity of current EF measurement methods for inferring information about in-game use of these cognitive abilities. [ABSTRACT FROM AUTHOR]

Little is known about motor competence and the longitudinal development of motor performance among youth with cystic fibrosis (CF). In this study, we assessed aspects of motor performance in different age groups of young patients with CF and compared them with a healthy reference group of same aged children. We also examined the development of motor performance among different age groups of these children with CF, using The Deutscher Motorik Test (DMT) to assess attributes of health-related and motor performance-related fitness. We used an incremental ergometer cycle test to determine maximal exercise capacity (expressed as peak workload). We evaluated and recorded habitual physical activity (PA) as measured by the number of steps per day and the time spent in different PA intensities (expressed in metabolic equivalents). In total, 31 children and adolescents with CF agreed to participate (13 girls,18 boys) aged 6–17 years (M = 11.3, SD =3.3 years); they had a mean one second forced expiratory volume (expressed as a percentage of predicted value [% pred]) of 87.2% (SD = 22.3%). We found their values of health-related and motor performance-related fitness to be significantly lower (p < 0.05) than those of their healthy peer participants. In contrast to the reference group, participants with CF up to 14 years of age showed a linear improvement in these values and in their PA, followed by a plateau or even a nonsignificant decrease after age 14. These findings have important implications for the development and prescription of exercise programs for children with CF. Besides aerobic and strength exercises, we recommend that neuromuscular training be integrated into exercise programs to improve the coordinative abilities of youth with CF. More attention should be paid to vulnerable older adolescents to ensure their long-term motivation to maintain exercise participation. [ABSTRACT FROM AUTHOR]

Fundamental Movement Skill (FMS) proficiency is an important antecedent of physical activity for children and adolescents. Many studies report children's overall FMS proficiency to be low. However, in order to develop effective intervention strategies, it is critical to understand FMS proficiency at a behavioral component level. This study investigated British primary school children's FMS proficiency across all three FMS domains, reporting proficiency at both an individual skill level and at a behavioral component level. Participants were 219 primary school children, aged 7–10 years (Boys 111, girls 108) from central England. We assessed (a) eight FMS (run, jump, hop, skip, catch, overarm throw, underarm throw, stability) using the second and third revisions of the Test of Gross Motor Development, and (b) stability, using the rock skill from the Rudd stability assessment tool. We calculated descriptive statistics and frequencies for each FMS and their behavioral components. We explored gender differences using the Mann- Whitney U-test, and differences between school years using the Kruskal- Wallis test. There was a similar pattern in the prevalence of failure for behavioral components across skills, with children failing on components requiring (a) the simultaneous use of both upper and lower limbs and (b) contralateral actions. Detailed descriptive analysis of low proficiency levels highlighted co ordination and the process for power/force production. These data can be used to guide development and plan targeted interventions for the weakest skills and behavioral components of 7-10 year old British primary school children to increase their FMS levels. [ABSTRACT FROM AUTHOR]

Physical activity has been positively related to better cognitive performance though the effects of varied exercise type and intensity and the duration of cognitive benefits are unclear. This study analyzed the effect of 16 minutes of monitored cooperative high-intensity interval training (monitored C-HIIT) at the start of the school day, on various cognitive variables over the next 24–48 hours. We randomly assigned 158 participants either to a control group (n = 81) that engaged only in static stretching or to an experimental group (n = 77) that performed monitored C-HIIT. We assessed cognitive functioning before the exercise, immediately afterward, and for five follow-up time points over the next two days (i.e., at 2, 3, 4, 24, and 48 hours). We analyzed age, sex, body mass index, and moderate-to-vigorous physical activity as potential confounder variables. Adolescents in the monitored C-HIIT group increased selective attention by 17.39% during the next hour (p = .015) and increased concentration by 20.31% and 15.26% during the first (p = .022) and second (p = .059) subsequent hours, respectively. This positive short-term benefit of monitored C-HIIT during immediate subsequent hours is an important finding with implications for the school curricula and schedule. [ABSTRACT FROM AUTHOR]

Previous studies investigating the association between fine-motor skills (FMS) and mathematical skills have lacked specificity. In this study, we test whether an FMS link to numerical skills is due to the involvement of finger representations in early mathematics. We gave 81 pre-schoolers (mean age of 4 years, 9 months) a set of FMS measures and numerical tasks with and without a specific finger focus. Additionally, we used receptive vocabulary and chronological age as control measures. FMS linked more closely to finger-based than to nonfinger-based numerical skills even after accounting for the control variables. Moreover, the relationship between FMS and numerical skill was entirely mediated by finger-based numerical skills. We concluded that FMS are closely related to early numerical skill development through finger- based numerical counting that aids the acquisition of mathematical mental representations. [ABSTRACT FROM AUTHOR]

While executive control (processes that facilitate the adaptation to new and/or complex situations) show an age-related decline, behavioral studies have observed stronger correlations between control and certain cognitive functions in older compared to young adults, which are often interpreted as an increase in the reliance on controlled processes with aging. Fifty-seven young adults (Mage=27.4 year, SD = 4.1) and 79 older adults (Mage=69.9 year, SD = 6.8) were administered several Fluid Reasoning, Control, and Representation measures. For the second step of the study, a group of 41 older adults (Mage=68.3 year, SD = 6.2) was selected as matching the young ones in terms of control measures. Correlations between fluid reasoning and control were stronger in older than in young adults. A General Linear Model analysis revealed a significant interaction between age and control variables. These results confirm the greater reliance on executive control in fluid reasoning performance in older adults, which may correspond to an active mechanism to cope with age-related difficulties. [ABSTRACT FROM AUTHOR]

Aging is accompanied by declines in cognitive and sensorimotor functions. However, at present, the interrelation between attentional processes and dexterity in aging has not been thoroughly addressed. This study explored the relationship between executive function, working memory, and dexterity performance in 15 young and 15 healthy elderly, right-handed participants. A modified version of the Purdue Pegboard Test was used for dexterity assessment. Two subtasks were selected to calculate temporal and kinematic parameters of reaching, grasping, transport, and insertion of pegs. Evaluation of executive function and working memory was performed using neuropsychological tests. The relationship between dexterity and cognitive outcomes were also examined. Results showed that the prehensile movements involved in grasping and their speed significantly differed between groups and correlated with executive function in the young group. For elderly adults, variability of hand movements turned out to be associated with executive abilities. [ABSTRACT FROM AUTHOR]

Technological advances have driven the development of information technology (IT) products and communication using mobile devices has become a part of daily life. When using mobile devices, reading time and font size are important communication elements that significantly affect reading performance. However, studies of reading performance in older samples have mainly used printed material or computer monitors; this study examined the performance of users when reading text messages on the interfaces of mobile devices and described their visual limitations. Sixty-two participants took part in the experiment, which involved displaying different font sizes and exposure times. The younger group read 10-point font accurately, while the older group had much worse accuracy, even at 14 points. The younger group correctly read text messages displayed for 0.4 sec. above 80% of the time, while the older group's accuracy was severely impaired even when text was displayed for 1 sec. [ABSTRACT FROM AUTHOR]

Girls are said to outperform boys in the human figure drawing, but some disagreement exists among studies regarding such sex differences, and the reasons for these sex differences are unclear. The study examined how sex, age, and graphic fluency affect scores at the human figure drawing in large sample of children aged five to 12 years. To that end, the Draw-a-Person Test was administered to 336 boys and girls from kindergarten to Grade 6, using Goodenough's scoring method. Graphic fluency was measured using Torrance's Parallel Lines Test. Results showed a sex by age interaction on scores at the Draw-a-Person test, with girls outperforming boys at Grades 3 and 6. Split-sample regression analyses indicated that for boys both age and graphic fluency were relevant predictors for scores on the Draw-a-Person test; by contrast, for girls age, but not fluency, predicted the drawing scores. It was concluded that graphic fluency differently affected boys' and girls' scores. [ABSTRACT FROM AUTHOR]

This study investigated differences between 50- to 70-yr.-old taxi and non-taxi drivers with respect to cognitive process-related skills. Psychological indicators associated with perceptuomotor, attentional, and spatial memory recall abilities were collected for 173 taxi drivers (7 women, 166 men; M age = 57.5 yr.) and 175 non-taxi drivers (85 women, 90 men; M age = 58.2 yr.). The taxi drivers had shorter reaction times and motor times in response to stimuli in simple stimulus-response tasks. There was an age-related decline in monocular vision detection on both sides, processing speed for fovea stimuli, and higher-level cognition for drivers. Accordingly, the frontal visual information processing speed of the taxi drivers was superior to the non-taxi drivers, but a distinct age-related decline was observed for all drivers. [ABSTRACT FROM AUTHOR]

Changes in physical self-concept and veridicality (i.e., the appropriateness of one's self-perceptions to reality) during childhood and adolescence are related to performance in physical fitness, exercise, and global self-esteem, particularly in male adolescents. This cross-sectional study examined the relation between the self-concept of strength and actual strength in groups of male adolescents ages 12 to 15 years. For this purpose, 889 male adolescents (M age = 13.2 yr., SD = 1.0) were questioned about their self-concept of strength, after which a test of strength was carried out. The results showed that the correlation between self- concept of strength and actual strength was higher in older (14- and 15-year-old) than younger (12- and 13-year-old) adolescents. There was a statistically significant association between age group and veridicality, indicating that realistic self-concept is under-represented among younger, but overrepresented among older adolescents. No association was found between the adolescents' physical activity and veridicality. The consequences for further research on the development of veridicality in the physical domain are discussed. [ABSTRACT FROM AUTHOR]

Providing a natural mapping between multi-touch gestures and manipulations of digital content is important for user-friendly interfaces. Although there are some guidelines for 2D digital content available in the literature, a guideline for manipulation of 3D content has yet to be developed. In this research, two sets of gestures were developed for experiments in the ease of manipulating 3D content on a touchscreen. As there typically are large differences between age groups in the ease of learning new interfaces, we compared a group of adults with a group of children. Each person carried out three tasks linked to rotating the digital model of a green turtle to inspect major characteristics of its body. Task completion time, subjective evaluations, and gesture changing frequency were measured. Results showed that using the conventional gestures for 2D object rotation was not appropriate in the 3D environment. Gestures that required multiple touch points hampered the real-time visibility of rotational effects on a large screen. While the cumulative effects of 3D rotations became complicated after intensive operations, simpler gestures facilitated the mapping between 2D control movements and 3D content displays. For rotation in Cartesian coordinates, moving one fingertip horizontally or vertically on a 2D touchscreen corresponded to the rotation angles of two axes for 3D content, while the relative movement between two fingertips was used to control the rotation angle of the third axis. Based on behavior analysis, adults and children differed in the diversity of gesture types and in the touch points with respect to the object's contours. Offering a robust mechanism for gestural inputs is necessary for universal control of such a system. [ABSTRACT FROM AUTHOR]

This study examined the internal consistency and construct validity of the Separation Anxiety Assessment Scale for Children in a non-clinical Italian sample of 358 children ages 6 to 10 years. Statistically significant differences were examined by sex and age. Two exploratory factor analyses were carried out: (a) on the symptom sub-dimensions which led to three interpretable factors of Fear of Abandonment and of Physical Illness, Fear of Calamitous Events, Fear of Being Alone and (b) on all Separation Anxiety Assessment Scale for Children items, which led to three interpretable factors: Fear of Abandonment and Safety Signals, Fear of Calamitous Events, and Fear of Being Alone and Left Alone. Preliminary findings for validity were described with the Separation Anxiety Symptoms Inventory for Children and the Italian Fear Schedule for Children (convergent validity). Implications regarding the clinical utility of the Separation Anxiety Assessment Scale for Children are discussed. [ABSTRACT FROM AUTHOR]

The main objective of the research was to analyse the cognitive expertise of volleyball players, according to their level of practice and age, as well as to verify the existing difference in the knowledge of individuals of the same age but with different levels of practice. The study sample was comprised of 535 individuals ages 12 to 16 years. The independent variables were the level of practice, i.e., playing category in training and in competition (Under-14 and Under-16), and the age. The dependent variables were declarative knowledge and procedural knowledge. An analysis of variance was performed to examine the influence of the level of practice on the declarative knowledge and procedural knowledge of the volleyball players in training stages. There were significant differences both in declarative knowledge and in procedural knowledge according to level of practice. Significant differences were also observed between consecutive ages at different levels of practice. These results show that the level of practice in training and competition is a more relevant factor than the change of age in development of specific knowledge of the sport. [ABSTRACT FROM AUTHOR]

The "dual klepsydra model" (DKM) of internal time representation successfully models duration reproduction data, but relations between the DKM-based parameter κ ("loss rate") and procedural variables (presentation modality) or individual characteristics (cognitive indices, age, sex) remained as yet unexplored. For that purpose, we re-analyzed data from an earlier time reproduction study (N = 100), using visually or acoustically presented intervals of 1--5 sec. duration. Typical values of parameter κ were ≈0.03--0.04 sec.-1, corresponding to relaxation times of internal "lossy integrators" of ≈30 sec. Significant effects of presentation modality (smaller κ values for the visual reproduction task) and of age (greater κ in acoustic reproduction with increasing age) were observed. Cognitive variables (working memory, general fluid reasoning, attention) and sex of participants were not associated with κ. Cognitive functions seem to play only a minor, if any, role at the level of time representation addressed by the DKM. [ABSTRACT FROM AUTHOR]

The kinematics of children's walking are nearly adult-like by about age 3-4 years, but metabolic efficiency of walking does not reach adult values until late in adolescence or early adulthood, perhaps due to higher coactivation of agonist/antagonist muscle pairs in adolescents. Additionally, it is unknown how use of a body weight-supported treadmill device affects coactivation, but because unloading will alter the activity of anti-gravity muscles, it was hypothesized that muscle coactivation will be altered as well. Muscle coactivation during treadmill walking was evaluated for adolescents (ages 10 to 17 years, M = 13.2, SD = 2.2) and adults (ages 22 to 35 years, M = 25.2, SD = 4.3), for thigh muscles (vastus lateralis/ biceps femoris) and lower leg muscles (tibialis anterior/gastrocnemius). Conditions included body weight unloadings from nearly 0% to 80% of body weight, while walking at a preferred speed (self-selected, overground speed) or a reduced speed. Unloading was accomplished using a lower body positive pressure support system. Coactivation was found to be higher in adolescents than in adults, but only for the lower leg muscles. [ABSTRACT FROM AUTHOR]

The purposes of this study were to examine the effects of different distances and the inclusion and exclusion of acceleration and deceleration distances on the measurement of self-paced and fastest gait speeds in younger and older adults. The self-paced and fastest gait speeds of younger and older adults were measured over 4-m and 10-m walkways with the acceleration and deceleration distances included and excluded in the measuring distance. The results indicated gait speeds (both self-paced and fastest) measured over different distances were comparable only if a distance for acceleration and deceleration was excluded from the measuring distance to obtain stable and comparable gait speeds. Similar results were found for younger and older groups. [ABSTRACT FROM AUTHOR]

Object control skills provide children the tools to be physically active-a major societal priority. At the fundamental movement level, object control skills form the foundation of further sports skill development. The purpose of this study was to examine children's (ages 5 to 14 years, Grades K-8) development of four key object control skills: catching, throwing, kicking, and striking. 186 children were tested on selected items from the Object Control Subtest of the Test of Gross Motor Development-2, using a cross-sectional and correlational design. As anticipated, significant differences were found for age on all four skills. These improvements were characterized by early, rapid gains at ages 9 to 10, beyond which development occurred at a slower rate for catching, throwing, and kicking; striking development continued at a steady rate to age 14 years. Contrary to previous findings, no overall sex differences were found for catching or kicking. Overall sex differences favoring boys were observed for throwing and striking. Implications for evolutionary contributions to throwing and striking were discussed. [ABSTRACT FROM AUTHOR]

This study was designed to compare tactile sensitivity of children and adults on printed target stimuli covering a wide range of elevations and requiring different resolutions. A recognition-relief task using 9 digits at 6 levels of elevation from a surface (0.5, 0.4, 0.3, 0.2, 0.1, and 0.05 mm) was presented to 24 young adults and 24 children. As predicted, relief elevations as low as 0.05 mm were recognized above chance. As predicted, children performed significantly more poorly than the adults on recognition at all elevations, although the difference increased as elevation increased. Adults performed significantly better than children on high-resolution digit 8, but there was no reliable age difference on low-resolution digit 1. Recognition difference between the high- and low-resolution digits decreased nonlinearly as elevation increased, irrespective of age. Overall, the findings support previous research indicating greater tactile sensitivity in adults than in children, but the superiority was moderated by the elevation and resolution requirements of the stimuli. [ABSTRACT FROM AUTHOR]