ABSTRACT
INTRODUCTION: The second to fourth-digit-ratio (2D:4D), a putative marker of prenatal androgen action and a sexually dimorphic trait, has been suggested to be related with fitness and sports performance, although results are not univocal. Most studies however focus on a single aspect of physical fitness or one sports discipline. METHODS: In this study the 2D:4D ratio of 178 adolescent girls (age 13.5-18 y) was measured on X-rays of the left hand. The relation between 2D:4D digit ratio and multiple aspects of physical fitness (balance, speed of limb movement, flexibility, explosive strength, static strength, trunk strength, functional strength, running speed/agility, and endurance) was studied by correlation analyses and stepwise multiple regression. For comparison the relation between these physical fitness components and a selected number of objectively measured anthropometric traits (stature, mass, BMI, somatotype components and the Bayer & Bailey androgyny index) are presented alongside the results of 2D:4D digit ratio. RESULTS: Left hand 2D:4D digit ratio (0.925±0.019) was not significantly correlated with any of the physical fitness components nor any of the anthropometric variables included in the present study. 2D:4D did not enter the multiple stepwise regression for any of the physical fitness components in which other anthropometric traits explained between 9.2% (flexibility) and 33.9% (static strength) of variance. CONCLUSION: Unlike other anthropometric traits the 2D:4D digit ratio does not seem to be related to any physical fitness component in adolescent girls and therefore most likely should not be considered in talent detection programs for sporting ability in girls.
Subject(s)
Fingers/growth & development , Functional Laterality , Hand/growth & development , Hand/physiology , Physical Fitness , Adolescent , Child , Female , Humans , Organ Size , Quantitative Trait, Heritable , Sex FactorsABSTRACT
The present study focused on the mechanism subserving the production of kinematic patterns in 21 children with 22q11.2DS (mean age=9.6+/-1.9; mean FSIQ=73.05+/-10.2) and 21 age- and IQ-matched control children (mean age=9.6+/-1.9; mean FSIQ=73.38+/-12.0) when performing a visuo-manual tracking task in which they had to track a cursor rhythmically between 2 target zones. Children with 22q11.2DS moved faster (overall) and reached their maximum velocity sooner when compared to controls. However, the number of corrective submovements to attain the target did not differ. Children with 22q11.2DS seem to adopt a young ballistic movement strategy, with a fast ballistic first movement phase, followed by a second movement phase with very little online corrections to attain the target. Children with 22q11.2DS are not able to process the incoming feedback during the second movement phase to maximize the accuracy of the ongoing movement and use this phase to prepare the following. The fact that the parietal cortex and cerebellum are involved in action prediction and internal representation and are implicated in children with 22q11.2DS provides a possible neurological basis for their problems with prospective control and tracking behavior.
Subject(s)
Chromosome Deletion , Chromosomes, Human, Pair 22 , DiGeorge Syndrome/physiopathology , Intellectual Disability/physiopathology , Motor Skills Disorders/physiopathology , Psychomotor Performance/physiology , Adaptation, Physiological/physiology , Age Factors , Biomechanical Phenomena , Child , DiGeorge Syndrome/genetics , Humans , Intellectual Disability/genetics , Intelligence , Motor Skills/physiology , Motor Skills Disorders/genetics , Movement/physiologyABSTRACT
To examine whether children with a 22q11.2 Deletion syndrome (22q11.2DS) are able to use prospective control, 21 children with 22q11.2DS (mean age=9.6+/-1.9; mean FSIQ=73.05+/-10.2) and 21 control children (mean age=9.6+/-1.9; mean FSIQ=73.38+/-12.0) were asked to perform a visuo-manual tracking task in which they had to track a cursor rhythmically between 2 target zones. Children with 22q11.2DS performed worse than the age- and IQ-matched controls (higher absolute time and distance errors) suggesting that the 22q11.2DS group experiences an additional (syndrome specific) processing deficit that cannot be attributed to their lower intellectual abilities. The 22q11.2DS group neither the control group improved their tracking performance throughout five identical full feedback conditions of the tracking task possibly due to a slow visuo-motor adaptation process, a short span of attention and cognitive flexibility impairments. The results showed that both the 22q11.2DS group and the controls had difficulties anticipating the movement of the target (prospective control) and thus are assumed to rely more on feedback instead of on an internal representation of the movement.
Subject(s)
Chromosome Deletion , Chromosomes, Human, Pair 22 , DiGeorge Syndrome/physiopathology , Intellectual Disability/physiopathology , Psychomotor Performance/physiology , Age Factors , Child , Cognition Disorders/genetics , Cognition Disorders/physiopathology , DiGeorge Syndrome/genetics , Feedback, Psychological/physiology , Humans , Intellectual Disability/genetics , Intelligence , Learning Disabilities/genetics , Learning Disabilities/physiopathology , Motion Perception/physiology , Reaction Time/physiologyABSTRACT
OBJECTIVE: To compare performance of children with acquired brain injury (ABI) on static versus dynamic visuomotor tasks with that of control children. PARTICIPANTS: Twenty-eight children with ABI and 28 normal age- and gender-matched controls (aged 6-16 years). MAIN MEASURES: Two visuomotor tasks on a digitizing tablet: (1) a static motor task requiring tracing of a flower figure and (2) a dynamic task consisting of tracking an accelerating dot presented on a monitor. RESULTS: Children with ABI performed worse than the control group only during the dynamic tracking task; the duration within the target was shorter, the distance between the centers of cursor and target was larger, and the number of velocity peaks per centimeter and the number of stops (ie, the number of submovements) were higher than those of the control group. Rather than resulting from movement execution problems, this might be due to less adequate processing of fast incoming sensory information, resulting in a decreased ability to anticipate the movement of the target (predictive control). CONCLUSION: Deficits in eye-hand coordination require careful attention, even in the postinjury chronic phase.
Subject(s)
Arousal , Attention , Brain Damage, Chronic/diagnosis , Brain Injury, Chronic/diagnosis , Motion Perception , Neuropsychological Tests/statistics & numerical data , Pattern Recognition, Visual , Psychomotor Disorders/diagnosis , Reaction Time , Adolescent , Brain Damage, Chronic/psychology , Brain Damage, Chronic/rehabilitation , Brain Injury, Chronic/psychology , Brain Injury, Chronic/rehabilitation , Case-Control Studies , Child , Female , Follow-Up Studies , Humans , Male , Orientation , Psychometrics , Psychomotor Disorders/psychology , Psychomotor Disorders/rehabilitation , Pursuit, Smooth , Reference ValuesABSTRACT
In the early publications on the 22q11.2 Deletion Syndrome (22q11.2DS) motor abnormalities have been frequently reported. However, systematic studies on the motor performance of children with the 22q11.2DS, and especially of school-age children, are scarce. In this study the motor performance of primary school-age children with a 22q11.2DS (n = 28) was compared with an age- and IQ-matched control group (n = 28) using the Movement Assessment Battery for Children (MABC), the Körperkoordinationstest für Kinder (KTK) and the Beery-Buctenica test of Visual-Motor Integration (Beery). Children with a 22q11.2DS scored significantly lower than the age- and IQ-matched control group on the subsection Manual Dexterity (MABC) and the Visual Perception and Motor Coordination subtests of the Beery. When investigating the correlations between Intelligence quotient (IQ) and motor performance, a specific profile was found in the 22q11.2DS group when compared with the age- and IQ-matched control group. Because an IQ-matched control group was adopted, the deficits in visual-perceptual and visuomotor integration skills cannot fully be attributed to a general developmental delay and thus may be specific for the 22q11.2DS. Future studies that investigate the specificity of the visual-perceptual problems - both on the behavioral and brain level (functional Magnetic Resonance Imaging [fMRI] and Diffusion Tensor Imaging [DTI]) - are necessary to answer this question. Nonetheless, the importance of incorporating motor functioning into the study of the neuropsychological profile of children with a 22q11.2DS has to be stressed.
Subject(s)
22q11 Deletion Syndrome/physiopathology , Intelligence/physiology , Psychomotor Performance/physiology , Visual Perception/physiology , Case-Control Studies , Child , Female , Humans , Intelligence Tests , MaleABSTRACT
The aim of this study was to compare the motor development of primary school children (age 5-14y) with a 22q11 deletion (del22q11) group and a control group. The effects of a congenital heart defect (CHD) and IQ on motor development were additionally studied within the del22q11 group. Motor development of 37 children with a del22q11 (20 males, 17 females; mean age 9y 4mo, range 5y 9mo-13y 3mo) and 34 controls (23 males, 11 females; mean age 9y 1mo, range 4y 8mo-13y 6mo) was assessed with the Bruininks-Oseretsky Test of Motor Proficiency. The del22q11 group showed a significant deficit in motor functioning compared with the control group (p < 0.01). Within the del22q11 group there was a significant effect of IQ on motor performance, but no effect of CHD was found. To conclude, primary school children with a del22q11 syndrome showed a significant deficit in motor performance compared with a control group. A significant effect of IQ on motor performance in del22q11 was found.
Subject(s)
Child Development/physiology , Chromosomes, Human, Pair 22 , DiGeorge Syndrome/complications , Motor Skills Disorders/etiology , Motor Skills/physiology , Adolescent , Analysis of Variance , Case-Control Studies , Child , Cognition Disorders/diagnosis , Cognition Disorders/etiology , Cognition Disorders/genetics , DiGeorge Syndrome/genetics , Female , Gene Deletion , Heart Defects, Congenital/complications , Heart Defects, Congenital/genetics , Humans , Intelligence/genetics , Male , Motor Skills Disorders/diagnosis , Motor Skills Disorders/geneticsABSTRACT
PURPOSE: To verify the applicability of the prediction equation for maturity offset in a sample of female gymnasts followed longitudinally through adolescence. METHODS: Fifteen gymnasts were followed longitudinally for 6-7 yr across adolescence. Weight, height, and sitting height were measured at annual intervals. The Preece-Baines Model I was fitted to longitudinal height data for individual gymnasts to derive age at peak height velocity (PHV). The curve-fitting protocol was successfully fit to the height records of 13 of the 15 gymnasts with standard errors of estimate between 0.02 and 0.28 cm. Maturity offset was calculated from measurements taken at each observation for the 13 gymnasts and also added to chronological age at each observation point to provide an estimated age at PHV. Age at PHV derived with the Preece-Baines model was used as the criterion. Differences between the criterion age at PHV and predicted age at PHV were calculated. RESULTS: Maturity offset overestimates age at PHV in gymnasts. Mean predicted ages at PHV deviate linearly from the criterion age at PHV, but the difference is significant only at 9 yr. Correlations between maturity offset predicted ages at PHV and criterion age at PHV range from -0.13 to +0.76. The Bland-Altman plot of criterion and predicted ages at PHV suggest a systematic bias in the predictions. CONCLUSION: Maturity offset appears to have limitations when applied to female gymnasts. Care is warranted in utilizing maturity offset per se and predicted age at PHV based on maturity offset as an indicator of maturity timing in female gymnasts and perhaps other short females.
