Somatotype in 6-11-year-old Italian and Estonian schoolchildren

The study of somatotypes can contribute to the understanding of variability in human body build. The aim of this study was to compare the somatotypes of Italian and Estonian schoolchildren in order to evaluate factors that might lead to variability in somatotypes. The sample consisted of 762 Italian and 366 Estonian children aged 6-11 years. They were somatotyped by the Heath-Carter anthropometric method. Data on organised extra-curricular physical activity and hours of weekly training were also collected. One-way ANOVA was used to evaluate country-related variations of somatotype in each age/sex group, while factorial ANOVA was used to test the influence of country and organised physical activity on the variability of the anthropometric characteristics and somatotype components.There are significant differences in mean somatotypes between the Italian and Estonian children in many age classes and a different constitutional trend in children from the two different countries is observed. The Italian children are more endomorphic and less mesomorphic and ectomorphic than the Estonian children. On the other hand, it emerges from factorial ANOVA, that the somatotype components do not present significant variations related to organised physical activity and to the interaction between the country of origin and sport practice. Moreover, the results of the forward stepwise discriminant analyses show that mesomorphy is the best discriminator between the two countries, followed by ectomorphy.Our findings suggest that the observed differences between Italian and Estonian children could be related mainly to country rather than to the practice of organised physical activity in the two countries.     

中国蒙古族体型特征

采用Heath-Carter体型法研究了中国蒙古族14个族群4810例（男性2117例,女性2693例）的体型。蒙古族内因子、中因子与年龄呈显著正相关,外因子与年龄呈显著负相关,即随年龄增长,身体线性度变小,体型趋于圆粗。蒙古族男性、女性体型都集中于偏内胚层的中胚层体型、内胚层-中胚层均衡体型、偏中胚层的内胚层体型。随着年龄增长,这3种体型的出现率均与年龄呈显著正相关,即蒙古族体型有向这3种体型集中的趋势。和汉族人相比,蒙古族身体更粗壮。主成分分析结果显示,东北三省蒙古族身体线性度小,体脂发达,骨骼和肌肉量较少。在体型图上北方蒙古族的点分布密集,说明北方蒙古族彼此体型比较接近,而南方的云南蒙古族由于内因子值小、外因子大,位点与北方蒙古族相距较远。在已经开展Heath-Carter体型法研究的中国族群中,蒙古族是体脂最为发达、身体线性度很小的民族。     

贵州革家人的体型

采用Heath-Carter人体测量法对家人成人311例(男159例,女152例)进行了体型研究。研究发现,家人男性的体型平均数为3.4-4.8-2.1,属于偏内胚层的中胚层体型;女性体型均数为4.9-4.7-1.3,属于内胚层-中胚层均衡型。家人性别间5个年龄组体型差异均具有统计学意义。随年龄增长,男性内因子值趋于变小,而且年龄组间内因子值具有明显差异。男性中因子、外因子与年龄均不相关,年龄组间中因子、外因子值的差异亦无统计学意义。女性内因子与年龄呈负相关,中因子、外因子与年龄均不具有相关(P>0.05)。内因子、中因子、外因子值在不同年龄组间的的差异具有统计学意义。家人男性与云南汉族、布依族、客家人、僜人、广西汉族体型接近,家人女性与客家人、怒族、僜人、侗族体型最为接近。在中国南方族群中,家人身体脂肪含量较多,骨骼、肌肉含量中等,身体相对粗壮些。家人与生活在南方的汉族族群体型相对接近。     

西藏藏族青少年体型

为了探讨藏族青少年体型发育特征及其规律, 本文应用Heath-Carter体型法对2530名藏族青少年体型进行评价。结果发现, 藏族青少年的平均体型男性为偏中胚层的外胚层型(2.40—3.29—3.72),女性为中间型(3.65—2.87—3.32); 男性的体型以外胚层系体型为主(58.52%), 女性体型以内胚层系(32.62%)和外胚层系为主(35.40%); 随着年龄的增长, 藏族青少年的体型发展有一定的规律, 男性由中胚层-外胚层均衡型经偏中胚层的外胚层型又发展回中胚层-外胚层均衡型, 女性由中胚层-外胚层均衡型经历均衡的外胚层型发展为均衡的内胚层型。因此, 本文认为,藏族男性青少年身体的线性程度高、外形上比较瘦削、肌肉较发达; 藏族女性青少年较男性身体的脂肪含量多、线性程度相对较高。     

Benefit of Bi-Ocular Visual Stimulation for Postural Control in Children with Strabismus

Vision is important for postural control as is shown by the Romberg quotient (RQ): with eyes closed, postural instability increases relative to eyes open (RQ = 2). Yet while fixating at far distance, postural stability is similar with eyes open and eyes closed (RQ = 1). Postural stability can be better with both eyes viewing than one eye, but such effect is not consistent among healthy subjects. The first goal of the study is to test the RQ as a function of distance for children with convergent versus divergent strabismus. The second goal is to test whether vision from two eyes relative to vision from one eye provides better postural stability. Thirteen children with divergent strabismus and eleven with convergent strabismus participated in this study. Posturtography was done with the Techno concept device. Experiment 1, four conditions: fixation at 40 cm and at 200 cm both with eyes open and eyes covered (evaluation of RQ). Experiment 2, six conditions: fixation at 40 cm and at 200 cm, with both eyes viewing or under monocular vision (dominant and non-dominant eye). For convergent strabismus, the groups mean value of RQ was 1.3 at near and 0.94 at far distance; for divergent, it was 1.06 at near and 1.68 at far. For all children, the surface of body sway was significantly smaller under both eyes viewing than monocular viewing (either eye). Increased RQ value at near for convergent and at far for divergent strabismus is attributed to the influence of the default strabismus angle and to better use of ocular motor signals. Vision with the two eyes improves postural control for both viewing distances and for both types of strabismus. Such benefit can be due to complementary mechanisms: larger visual field, better quality of fixation and vergence angle due to the use of visual inputs from both eyes.     

Physical fitness differences between prepubescent boys and girls

The purpose of this study was to analyze in which physical capabilities boys and girls are closer or distant. An additional objective was to find which of the body fat, physical activity, and somatotype factors have a greater effect on prepubescent children's physical fitness. This was a cross-sectional study involving 312 children (10.8 ± 0.4 years). The physical fitness assessment employed sets of aerobic fitness, strength, flexibility, speed, agility, and balance. The boys presented higher values in all selected tests, except tests of balance and flexibility, in which girls scored better. Gender differences in the physical fitness were greatest in the explosive strength of upper (p ≤ 0.01, η(p)(2) = 0.09) and lower limbs (p ≤ 0.01, η(p)(2) = 0.08), although with a medium-size effect of gender, and smaller in the abdominal (p > 0.05, η(p)(2) = 0.007) and upper limbs (p > 0.05, η(p)(2) = 0.003) muscular endurance, and trunk extensor strength and flexibility (p > 0.05, η(p)(2) = 0.001). The endomorphic (p ≤ 0.01, η(p)(2) = 0.26) in the girls, and the ectomorphic (p ≤ 0.01, η(p)(2) = 0.31) and mesomorphic (p ≤ 0.01, η(p)(2) = 0.26) in the boys, had the high-sized effect on the physical fitness. The physical activity in the girls, and the endomorphic and body fat in the boys, did not have a significant effect. These findings can help in the planning of activities that take into account the success and motivation of both boys and girls and thus increase levels of physical activity and physical fitness at school. However, in prepubescent children, one cannot neglect the influence of genetic determinism, observed from the morphoconstitutional point of view.     

Development of the energetics of muscular exercise with age: Summary of a 30-Year study: IV. The development of the energetics of skeletal muscles depending on the somatotype

The report is based on the results of an 11-year longitudinal study on the age-dependent changes in the muscular working capacity in 7-to 17-year-old boys and girls with different somatotypes. Type-specific features of the development of the energetics of skeletal muscles and sex-related differences in the typological structure of the sample have been found. Somatotype-predisposed differences in the structure of the energy supply of muscular exercise are shown.     

The influence of adipose tissue location on postural control

A growing body of evidence suggests, that excessive body weight is inseparably connected with postural instability. In none of previous studies, body weight distribution has been considered as a factor, which may affect results of a static posturography. The purpose of the present study is to quantify some center of foot pressure (COP) characteristics in 40 obese women with android type of obesity (waist-to-hip ratio - WHR ≥ 0.85, BMI: 37.5 ± 5.4) and 40 obese women with gynoid type of obesity (WHR < 0.85, BMI: 36.9 ± 5.1). Variables of postural sway were acquired while subjects were standing quietly on a force plate with eyes open and closed. Both in the sagittal and frontal plane sway range, average velocity, and maximal velocity of COP were calculated. Moreover, the total average velocity and total maximal velocity of the COP displacement were computed.Women with abdominal obesity showed a larger sway range in the anterior-posterior plane with eyes open (p < 0.0282) and eyes closed conditions (p < 0.0115) and a greater maximal COP velocity to compare with subjects with gynoidal obese type (p < 0.0112) with eyes closed condition.The postural stability in obese women from the biomechanical point of view is strongly dependent on body distribution. Women with the abdominal obesity type may be exposed to a greater risk of postural instability as compare to women with gynoid fat distribution.     

布依族成人Heath-Carter法体型研究

本文运用Heath-Carter人体测量体型方法,研究了贵州省布依族494例(男259例,女235例)成人体型。研究结果表明:(1)布依族男性与女性平均体型均为偏内胚层的中胚层体型,男性均数为3·0—5·3—2·4,女性均数为4·3—4·9—1·9。(2)随年龄增长,布依族男性内因子值变化不大,中因子值增大,外因子值减小。但总的说来,男性体型各年龄组变化不大。(3)随年龄增长,女性内因子值与中因子值增大,外因子值减小。(4)布依族体型介于南方人群和北方人群之间。     

The spectral content of postural sway during quiet stance: Influences of age, vision and somatosensory inputs

Maintenance of human upright stance requires the acquisition and integration of sensory inputs. Conventional measures of sway have had success in identifying age- and some disease-related changes, but remain unable to address the complexities and dynamics associated with postural control. We investigated the effects of vision, surface compliance, age, and gender on the spectral content of center of pressure (COP) time series. Sixteen healthy young (age 18-24) and older participants (age 55-65) performed trials of quiet, upright stance under different vision (eyes open vs. closed) and surface (hard vs. compliant) conditions. Spectral analyses were conducted to describe COP mean normalized power in discretized bands. Effects of the two sensory modalities and age were distinct in the antero-posterior and medio-lateral directions, and a reorganization of spectral content was evident with increasing task difficulty (eyes open vs. closed and hard vs. compliant surface) and among older adults. These results indicate that vision and surface compliance are predominantly associated with responses from musculature associated with antero-posterior and medio-lateral directions of sway, respectively. Finally, distinguishing between the contributions of different afferent systems to the postural control system using the spectral content of sway bi-directionally may help in diagnosing individuals with balance impairments.     

Sex, age and caste differences in somatotypes of Rajput and scheduled caste adolescents from the Sirmour District of Himachal Pradesh, India

Somatotypes of a cross-sectional sample of 544 rural adolescents ranging in age from 11 to 17 years are described. The sample included 269 Rajput (141 girls and 128 boys) and 275 Scheduled Caste (135 girls and 140 boys) subjects. Each subject was somatotyped using the Heath-Carter anthropometric somatotype protocol (Carter & Heath 1990). In all, ten anthropometric measurements namely height, weight, bicondylar diameters of humerus and femur, flexed mid-upper-arm and calf circumferences, and triceps, subscapular, supraspinale and calf skinfolds were taken. The mean somatotypes of the Rajput boys and girls were 1.62- 3.30-3.85 (mesomorphic-ectomorph) and 2.42-2.90-3.99 (balanced ectomorph), respectively. The mean somatotypes of the Scheduled Caste subjects were 1.51-3.02-3.74 (mesomorphic-ectomorph) for boys and 2.38-2.64-3.70 (balanced ectomorph) for girls. A one-way ANOVA revealed that females of both the caste groups were significantly (p < or = 0.05) more endomorphic than the males. The sex differences in other two components were not significant (p +/- 0.05). Caste differences, as revealed by a one-way ANOVA analysis, were not significant (p +/- 0.05) in both sexes. With the exception of the Rajput girls, the differences in whole somatotypes between those in an early phase of adolescence and those in an advanced phase of adolescence were not significant (p = 0.05). The results indicate that populations exposed to same environmental situations for a long period of time tend to show similarity in physique. A one-way MANOVA analysis, which used Wilk's Lambda as test statistics, revealed that from 11-17 years there was no significant change (p < or = 0.05) in component dominance of mean somatotypes in the boys and girls of the present sample. Among males of a majority of the Indian populations, ectomorphy dominates over endomorphy and mesomorphy from 11 to 17 years.     

Postural Stability in Young Adults with Down Syndrome in Challenging Conditions

To evaluate postural control and performance in subjects with Down syndrome (SwDS), we measured postural sway (COP) in quiet stance in four 20-second tests: with eyes open or closed and on hard or foam surface. Ten SwDS and eleven healthy subjects participated, aged 29.8 (4.8) and 28.4 (3.9), respectively. The time-series recorded with the sampling rate of 100 Hz were used to evaluate postural performance (COP amplitude and mean velocity) and strategies (COP frequency, fractal dimension and entropy). There were no intergroup differences in the amplitude except the stance on foam pad with eyes open when SwDS had larger sway. The COP velocity and frequency were larger in SwDS than controls in all trials on foam pad. During stances on the foam pad SwDS increased fractal dimension showing higher complexity of their equilibrium system, while controls decreased sample entropy exhibiting more conscious control of posture in comparison to the stances on hard support surface. This indicated that each group used entirely different adjustments of postural strategies to the somatosensory challenge. It is proposed that the inferior postural control of SwDS results mainly from insufficient experience in dealing with unpredictable postural stimuli and deficit in motor learning.     

Difference in Postural Control during Quiet Standing between Young Children and Adults: Assessment with Center of Mass Acceleration

The development of upright postural control has often been investigated using time series of center of foot pressure (COP), which is proportional to the ankle joint torque (i.e., the motor output of a single joint). However, the center of body mass acceleration (COM_acc), which can reflect joint motions throughout the body as well as multi-joint coordination, is useful for the assessment of the postural control strategy at the whole-body level. The purpose of the present study was to investigate children’s postural control during quiet standing by using the COM_acc. Ten healthy children and 15 healthy young adults were instructed to stand upright quietly on a force platform with their eyes open or closed. The COM_acc as well as the COP in the anterior–posterior direction was obtained from ground reaction force measurement. We found that both the COM_acc and COP could clearly distinguish the difference between age groups and visual conditions. We also found that the sway frequency of COM_acc in children was higher than that in adults, for which differences in biomechanical and/or neural factors between age groups may be responsible. Our results imply that the COM_acc can be an alternative force platform measure for assessing developmental changes in upright postural control.     

山东省潍坊地区汉族青少年Heath-Carter法体型研究

应用HeathCarter人体测量法对山东省潍坊地区2511名（男1253名、女1258名）7—19岁的汉族学生进行了体型评定。结果是：城市汉族男生平均体型7—15岁为三胚层中间型,16—18岁为内胚层-中胚层均衡型;乡村男生平均体型7—10岁为中胚层-外胚层均衡型,11—14为偏中胚层的外胚层体型,15—17岁为三胚层中间型,18—19岁为内胚层-中胚层均衡型。城市女生平均体型7—9岁为三胚层中间型,10岁为均衡的内胚层体型,11—12岁为外胚层-中胚层均衡型,13—18岁为均衡的内胚层体型;乡村女生7—12岁为均衡的外胚层体型,13—14岁为内胚层-外胚层均衡型,15—18岁为均衡的内胚层体型。     

The effects of the load mass and load position on body sway in supporting a load on the back

We examined the effects of a load's mass and position on body sway during standing with a load on the back. Three healthy male subjects participated in this experiment. The subjects supported loads of 23kg, 33kg, and 43kg on their backs using a carrier frame. They were asked to stand for 75s on a force platform with their eyes open while being as quiet as possible. Time series data of center-of-pressure (COP) were collected at a sampling rate of 50Hz during the last 60s of the 75s standing period. The COP was measured under three conditions in terms of the load position on the frame: lower (close to the hip), middle, and upper (close to the shoulder). All subjects showed that the lower the position of the load, the more anteriorly the mean COP coordinate was located in the anteroposterior (AP) direction, and the smaller the total distance of the COP trajectories became. Regarding carrying the heavier loads, each subject showed a specific tendency in the mean AP coordinate. The three subjects had different physical characteristics in terms of body height and experience at carrying heavy loads. These results suggest that the examintion of the COP in a static posture can help our understanding of individual information on the posture supporting loads and the general positioning of the body.     

Effects of two passive back-support exoskeletons on postural balance during quiet stance and functional limits of stability

While occupational back-support exoskeletons (BSEs) are considered as potential workplace interventions, BSE use may compromise postural control. Thus, we investigated the effects of passive BSEs on postural balance during quiet upright stance and functional limits of stability. Twenty healthy adults completed trials of quiet upright stance with differing levels of difficulty (bipedal and unipedal stance; each with eyes open and closed), and executed maximal voluntary leans. Trials were done while wearing two different BSEs (SuitX™, Laevo™) and in a control (no-BSE) condition. BSE use significantly increased center-of-pressure (COP) median frequency and mean velocity during bipedal stance. In unipedal stance, using the Laevo™ was associated with a significant improvement in postural balance, especially among males, as indicated by smaller COP displacement and sway area, and a longer time to contact the stability boundary. BSE use may affect postural balance, through translation of the human + BSE center-of-mass, restricted motion, and added supportive torques. Furthermore, larger effects of BSEs on postural balance were evident among males. Future work should further investigate the gender-specificity of BSE effects on postural balance and consider the effects of BSEs on dynamic stability.     

Age-related changes and sex differences in postural control adaptability in children during periodic floor oscillation with eyes closed

We investigated age-related changes and sex differences in adaptability of anticipatory postural control in children. Subjects comprised 449 children (4-12 years old) and 109 young adults (18-29 years old). Subjects stood with eyes closed on a force-platform fixed to a floor oscillator. We conducted five trials of 1-minute oscillation (0.5 Hz frequency, 2.5 cm amplitude) in the anteroposterior direction. Postural steadiness was quantified as the mean speed of the center of pressure in the anteroposterior direction (CoPy). In young adults, CoPy speed decreased rapidly until the third trial for both sexes. Adaptability was evaluated by changes in steadiness. The adaptability of children was categorized as "good," "moderate," and "poor," compared with a standard variation of the mean CoPy speed regression line between the first and fifth trials in young adults. Results were as follows: (1) anticipatory postural control adaptability starts to develop from age 6 in boys and 5 in girls, and greatly improves at age 7-8 in boys and 6 in girls; (2) the adaptability of children at age 11-12 (74% of boys and 63% of girls were categorized as "good") has not yet reached the same level as for young adults; (3) the adaptability at age 11-12 for girls is temporarily disturbed due to early puberty.     

PREVIOUS PHYSICAL ACTIVITY AND BODY BALANCE IN ELDERLY PEOPLE

The purpose of the research was to evaluate the efficiency of body balance regulation in the elderly and verify whether physical activity in adolescence could influence later physical efficiency. Research was carried out on 62 persons aged between 65 and 96 years of age. Fifty people declared that they undertook physical activity in adolescence, while 12 reported no activity. Stabilographic examinations were performed during trials with open and closed eyes on a horizontally situated platform tilted forward and backward. The centre-of-pressure (COP) path length, sway range area and centre-of-pressure velocity (COP velocity) were assessed. The safety margin when a person leans forward and backward was evaluated as well. On a horizontally situated platform, exclusion of visual control in most of the examined participants resulted in a significant increase in values of examined parameters. Tilting the platform caused in both groups an increase in values of all the parameters. These changes were more visible when a trial with eyes closed was performed and the group of active people obtained better results. These people were also able to use the support area more effectively when changing the position of the body. It was found that body balance disorder affects more often elderly people who were less active in adolescence and that with age visual balance control dominates the proprioceptive one. This means that physical activity directed towards, among other things, forming and improving the body balance regulation system is needed at an early age.     

Effect of locomotor training and functional electrical stimulation on postural function in children with severe cerebral palsy

Cerebral palsy (CP) considerably impairs the ability to maintain upright stance. The effects of locomotor training and functional electrical stimulation (FES) on postural control were determined in 27 children aged 6–12 years with severe CP. The severity level of the clinical manifestations of CP was classified as 3 according to the Gross Motor Function Classification System (GMFCS). All patients participated in 15 30-min mechanical therapy sessions using robot-assisted passive stepping. In 12 out of 27 children, the locomotion therapy was accompanied by FES. Stabilometry and plantography tests were performed in 23 healthy age-matched children. Postural control in children with CP differed from the stabilograms of healthy children in a forward shift of the center of pressure (COP) projection; higher values of the COP trajectory area and length, the mean amplitude of the COP oscillations, and the absence of COP response to the eyes closed condition. After treatment, the posturographic characteristics tended to normalize in relation to the values obtained in neurologically intact children. The improvement was observed in 43% of children without FES and in 75% of children in the group with FES. Analysis of plantograms revealed normalization of footprints in children who received FES. Thus, it was demonstrated that FES combined with locomotor training resulted in the improvement in vertical posture control in children with severe CP.