Children with mild intellectual disability (MID) have significant limitations in both intellectual functioning and cognitive, social, and motor skill behaviors. Understanding the development of physical fitness in boys and girls with MID, and identifying sex-related differences can help devise interventional programs to improve physical fitness in these groups. The aim of this study was to compare sex differences in the time-dependent changes in health-related physical fitness components in individuals with MID. A longitudinal design was employed over three years. A total of 111 individuals with MID (46 girls and 65 boys) aged between 10 and 14 years (mean age 11.97±1.39 years) participated in the study. The physical fitness levels of the participants were assessed using the Brockport Physical Fitness Test (BPFT) battery. The tests included body composition (body height, body mass, and body mass index), aerobic endurance (15 m Progressive Aerobic Cardiovascular Endurance Run (PACER) test), and musculoskeletal function (dominant handgrip strength, back-saver sit-and-reach, and trunk lift). The results revealed that, over time, the longitudinal developmental trajectories for body mass, body height, aerobic endurance, and dominant handgrip strength were more favorable for boys. However, the longitudinal development curves for body mass index (BMI), trunk lift, and flexibility were similar for both boys and girls. The findings of this study provide valuable evidence for developing targeted physical activity programs for individuals with MID, and demonstrate the need for programs aimed at increasing aerobic endurance and muscle strength in girls with MID.

Aims: Our objective is to explore changes in body fat distribution and muscle strength among a cohort of girls with idiopathic central precocious puberty (ICPP) undergoing the gonadotropin-releasing hormone analogs (GnRHa) therapy. Methods: A total of 50 patients who were newly diagnosed with ICPP and treated with GnRHa were included in the study. Patients were investigated at baseline, 6th months and 12th months. Results: Body-mass index (BMI) standard deviation score (SDS) was similar throughout the treatment duration. The percentage of body fat (PBF) increased from 24.2±5.1% at the beginning to 26.3±5.3% at the 6th month and to 27.7±5.43% at the 12th month (p

Abstract Disclosure: R. Dhaliwal: None. R.K. Saunders: None. M. Misra: None. M.L. Bouxsein: None. D.M. Mitchell: None. Introduction: Type 1 diabetes (T1D) confers an increased fracture risk, only partly explained by low areal bone mineral density (aBMD). We have previously shown in a cross-sectional study that bone microarchitecture is altered early in the course of T1D. The goal of this study is to evaluate how T1D influences longitudinal changes in volumetric BMD (vBMD) and microarchitecture. Methods: This is a 2-year prospective study of girls ages 10-16 years (62 with T1D and 59 controls). We used dual-energy x-ray absorptiometry (DXA) to measure aBMD, and high-resolution peripheral quantitative computed tomography (HR-pQCT) at the distal radius (7% site) and tibia (8% site) to measure vBMD and microarchitecture. We used linear mixed models to assess the effects of T1D on change in bone parameters over time, adjusting for bone age as an index of skeletal maturity, height, lean mass index (LMI), and fat mass index (FMI). Results: At baseline, mean duration of disease in T1D was 4.8 ± 3.2 years, and mean HbA1c was 8.6 ± 1.4%. The groups did not differ by age, bone age, and height, while T1D participants had higher LMI (p<0.001) and borderline higher FMI (p=0.107). Linear growth, weight gain, and changes in body composition over time did not differ between groups. Growth-mediated aBMD gains were observed in both groups at the subtotal body, total hip, femoral neck, and spine. While adjusted aBMD as well as trabecular bone score were lower in T1D, we did not observe between-group differences in changes in these endpoints over time. In both groups, at the distal radius, we observed significant increases over time in total and cortical vBMD, cortical thickness, trabecular (Tb) thickness, and estimated failure load, while cortical porosity decreased. While several microarchitectural parameters were altered in T1D participants, we did not observe significant between-group differences in changes in these measures over time. Of note, trabecular development was subtly altered, with T1D participants demonstrating a borderline significant decrease in Tb vBMD (-14.3 ± 9.0 mg HA/cm3, p=0.112) and Tb number (-0.14 ± 0.07 mm-[1], p=0.057), while control participants had no change in Tb vBMD or number, but a significant increase in Tb thickness (5.8 ± 2.5 µm, p=0.018). At the distal tibia, we observed similar overall detrimental effects of T1D at baseline. However, we did not observe between-group differences in microarchitectural change over time. Glycemic control as measured by HbA1c was not associated with changes in skeletal parameters among T1D participants. Conclusions: T1D leads to substantially altered areal and volumetric BMD as well as microarchitectural parameters in girls. While our data suggest that much of this deficit appears to occur early in the course of disease as prospective change is similar in T1D and controls, subtle changes in trabecular bone development at the radius may indicate ongoing impairment of bone accrual. Presentation: 6/3/2024

Background: Measuring and comparing grip and pinch strengths with their normative data is a valid method to detect intensity of the numerous damages of hand. The aim of the study was to establish the normative data of grip strength and three types of pinch strengths (Key, Tip and Palmar) in healthy Saudi’s children. Method: In this cross-sectional study, of grip strength and three types of pinch strengths (Tip, Key and Palmar) were recorded for 82 healthy children (41 boys and 41 girls) heathy children aged 7-18 years. The Camry Electronic Hand Dynamometer and Hydraulic Pinch Gauge were used to measure grip strength and pinch strength, respectively. Result: Normative data of grip and pinch strengths were provided. Grip and pinch strengths of both genders were close to each other’s and increasing consistently with increasing age. The maximum grip strength and pinch strength was obtained in the group of 14-18 years among both genders. In addition: Study results showed that there was a significant association between weight and all the hand grip strength and pinch strength (p < 0.05) in boys whereas BMI considered as an effective parameter on grip strength and tip pinch strength in girls. Conclusions: Findings from the present study provide reference values for hand grip strength and pinch strength for healthy children from 6- which will be useful to guide rehabilitation outcomes in routine clinical practice.18 years of age which will be useful to guide rehabilitation outcomes in routine clinical practice.

The article determined the physical development and state of the cardiovascular system of students of Biology Faculty. 45 first-year students (36 female and 9 male) and 17 fourth-year students (10 female and 7 male) participated in the study. Calculations of the shoulder musculature development index, relative strength index and correlation analysis of the dependence of the adaptation potential on the relative strength index were carried out. Comparing the results of measuring the muscle development index among girls, we found that the weak and medium levels of this indicator prevailed in fourth-year students compared to first-year students. Good development of musculature prevailed in female students of the 1st year. Comparing the results of the assessment of physical development among girls, we found that the low degree of this indicator prevailed in students of the IV year compared to the I year, physical development within the norm was found only in the students of the I year. Among the boys, a low degree of physical development prevailed in students of the first year, physical development within the norm was observed only in students of the fourth year. We established that there was not a single student with a high level of physical development among the boys of the 1st and 4th years The obtained values of adaptation potential were used to assess the adaptation capabilities of students. 50% of girls and 78% of boys had stress adaptation mechanisms, so they were recommended to do physical exercises according to a special program, 50% of the examined girls and 22% of boys had satisfactory adaptation, it was recommended to exercise without restrictions. After conducting a correlation analysis of the adaptation potential and the index of relative strength, we can note that there is a reliable weak negative correlation (r = –0.3, p ≥ 0.95) in girls, students of the 1st year, and a reliable average negative correlation in girls, students of the 4th year (r = –0.7, p ≥ 0.95). With a decrease in adaptation potential, the index of relative strength in first- and fourth-year girls increases significantly. Therefore, the application of hand dynamometry methods in combination with the index of muscle development allowed us to establish that in girls of the 1st and 4th years, indicators within and above the norm prevail. According to the results of the correlation analysis, it was established that with the decrease in the adaptation potential, the index of relative strength in girls of the first and fourth years increases reliably. A satisfactory level of adaptation was found in the majority of students. A higher percentage of persons with satisfactory adaptation was observed among female students than among male students. This is probably explained by greater resistance to stress, hormonal differences, and fewer individuals with bad habits among girls. Students who belong to the first health group can be recommended to increase physical activity and abandon habits that are harmful to health. Individuals belonging to the second group need preventive measures aimed at preventing the development of various diseases (individually in each case).

The article presents the results of a comparative analysis of indicators of physical development in adolescent girls with insufficient and normal body weight. The aim of the study was to assess the impact of insufficient body weight on indicators of physical development in adolescent girls. Methods and organization of the study: theoretical analysis of specialized literature, comparative analysis, anthropometric research methods, and methods of mathematical statistics. Girls aged 12-13 took part in the study (a total of 138 persons, including 108 girls aged 12 and 30 girls aged 13). Results. The results of the comparative analysis showed statistically significant difference (p < 0.05) in some indicators of physical development between the girls with insufficient body weight and girls with normal body weight. The 12-year-old girls with insufficient body weight had statistically significantly lower (p < 0.05) body weight, waist circumference, and left-hand grip strength than their peers with normal body weight. In contrast to 12-year-old girls, 13-year-old girls with insufficient body weight had all median indicators of physical development, except for shoulder circumference, lower then the girls of this age with normal body weight. In 13-year-old girls with insufficient body weight, the decrease in the indicators of physical development is larger than in 12-year-old girls, that is, the negative impact of insufficient body weight on the physical development of girls intensifies. Insufficient body weight was accompanied by a decrease in the group averages of hand grip strength in girls. A negative trend was demonstrated, which indicates that insufficient body weight impairs the normal development of the child's body. Conclusions. The results of the study demonstrated significant differences in the indicators of physical development between girls with normal and insufficient body weight.

The main purpose of the study was to evaluate the secular trends in physical fitness of Chinese rural children and adolescents aged 7–18 from 1985 to 2019. The speed, muscular strength, explosive power fitness, cardiorespiratory fitness, and flexibility were investigated by National Survey on Students’ Constitution and Health in 1985, 2000, 2010 and 2019. During the period 1985–2000, the physical fitness of Chinese rural children and adolescents improved except for flexibility, and almost all of them reached the maximum increase rate. During the period 2000–2010, in addition to the improvement of flexibility, other fitness showed downward trends, and the decline ranges were large. During the period 2010–2019, the speed of boys rebounded, flexibility, explosive power and muscular strength continued to decrease. Meanwhile, speed, flexibility and muscular strength in girls rebounded, and the explosive power continued to decline. From 2000 to 2019, the body mass index increase accelerated. This study shows that some components of physical fitness of Chinese rural children and adolescents have shown positive trends in recent years, especially for girls and adolescents aged 13–15 years. However, it may also imply inequality between sexes and ages, which provides a reference for the focus of the country's physical fitness and health monitoring and intervention measures.

Physical activity during adolescence is important to obtain peak bone mass; however, adolescents are increasingly sedentary, potentially increasing risk for osteoporosis later in life. The aim of this study was to assess the association of physical activity and sedentary time with 2-year longitudinal bone outcomes in adolescent females (69% Hispanic/31% non-Hispanic). Bone strength was assessed at the 66% tibia, 20% femur, and 66% radius of 9- to 12-year-old girls (n = 131) using peripheral quantitative computed tomography at baseline and 2-year follow-up. Physical activity and sedentary time were assessed via accelerometry. Linear regression analyses were used to assess whether baseline vigorous physical activity (VPA), moderate physical activity (MPA), light physical activity (LPA), or sedentary time predict longitudinal bone outcomes, adjusting for relevant confounders. Significant interactions were found between maturity offset and physical activity. In weight-bearing bones, significant interactions were primarily identified between VPA and maturity offset. Interactions indicated that VPA was associated with favorable bone outcomes at the tibia and femur in girls further past the age of PHV. However, this favorable effect was not observed in girls closer to the age of PHV. At the radius, interactions were primarily observed between LPA and maturity offset. Again, LPA was more beneficial for girls further past the age of PHV. Sedentary time did not significantly influence bone outcomes. The effects of physical activity on bone may be dependent on maturity. Therefore, physical activity interventions, with attention to maturity status, may be required to optimize bone strength in girls.

We recently reported impaired bone strength in girls with low- to moderate-energy distal radius fractures (Fx) compared with girls with no history of forearm fractures (Non-Fx). We aimed to determine whether bone strength deficits observed at baseline were still present after 2 years. We assessed bone strength, microarchitecture, and bone mineral density (BMD) of the non-fractured (Fx) and non-dominant (Non-Fx) distal radius (7% site) at baseline, 12, and 24 months using high-resolution pQCT (Scanco Medical, Brüttisellen, Switzerland) in 104 girls (aged 11.0 ± 1.7 years; 47 Fx, 57 Non-Fx) and 157 boys (aged 12.7 ± 1.7 years; 86 Fx, 71 Non-Fx). Bone outcomes included total area (Tt.Ar) and bone mineral density (Tt.BMD), trabecular bone volume ratio (BV/TV), thickness (Tb.Th), separation (Tb.Sp), and number (Tb.N), and cortical BMD (Ct.BMD), thickness (Ct.Th), and porosity (Ct.Po). We used finite element analysis to estimate bone strength (failure load [F.Load]; ultimate stress [U.Stress]; load-to-strength ratio). We used sex-specific mixed-effects models to compare bone outcomes between Fx and Non-Fx over 2 years. In girls, those with fractures had 18% to 24% lower U.Stress and 5% to 9% lower Tt.BMD than Non-Fx at all time points (p < 0.017). In secondary analysis by fracture degree, girls with low-energy (LE) fractures had 19% to 21% lower F.Load, 25% to 47% lower U.Stress, 11% to 14% lower Tt.BMD, and 11% to 15% lower BV/TV than Non-Fx at all time points (p < 0.017). In contrast, boys' bone outcomes were similar between Fx and Non-Fx at all time points. In secondary analysis by fracture degree, boys with LE fractures had 10% lower Tt.BMD and 10% lower Ct.Th compared with Non-Fx at 12 months only. Deficits in distal radius bone strength and trabecular bone microarchitecture appear to track across 2 years after a forearm fracture in girls but not in boys. Longer follow-up is needed to determine whether deficits persist into adulthood in women and how they may influence future risk of fragility fracture. © 2017 American Society for Bone and Mineral Research.

Searchable abstracts of presentations at key conferences on calcified tissues ISSN 2052-1219 (online)

The aim of the research was to assess influence of a 90-minute specialist fencing training on selected features of the spine and pelvis under a vertical load in a group of young competitors. The research was carried out in 2015 among 23 fencers (mean &plusmn; SD, age: 16 &plusmn;1.20 years; body height: 168.4 &plusmn;4.68 cm; body weight: 54.7 &plusmn;8.26 kg). The method involved measurement of thirty features, describing spatially pelvis and physiological spinal curvature under a vertical load, constituting 1/3 of the body weight before and after specialist training. Statistically significant disturbances in vertically overstretched posture occurred after the training among examined boys within the following features: increase in length of left side scoliosis, progression of lumbar lordosis and lumbosacral spine, increase of the trunk extension angle and shoulder asymmetry. Among examined girls statistically significant changes occurred only within pelvis area: increase of left pelvic tilt in the coronal plane, decrease of right pelvic tilt in the horizontal plane. Adjustment in deficiencies within hip joints movement, increase pelvis and lower limbs muscle strength in girls&rsquo; training is necessary. What is recommended for all competitors is prophylaxis of the spinal pain syndrome and expanding endurance shaping exercises during a training unit.

Background and methodsThere is a paucity of data on contemporary secular trends on the different aspects of physical fitness in school-aged children and adolescents. This study presents the largest ever...

Poor muscle quality and sedentary behavior are risk factors for metabolic dysfunction in children and adolescents. However, because longitudinal data are scarce, relatively little is known about how changes in muscle quality and physical activity influence bone development. In a 2-yr longitudinal study, we examined the effects of physical activity and changes in muscle quality on bone parameters in young girls. The sample included 248 healthy girls age 9-12 yr at baseline. Peripheral quantitative computed tomography was used to measure calf and thigh muscle density, an indicator of skeletal muscle fat content or muscle quality, as well as bone parameters at diaphyseal and metaphyseal sites of the femur and tibia. Physical activity was assessed using a validated questionnaire specific for youth. After controlling for covariates in multiple regression models, increased calf muscle density was independently associated with greater gains in cortical (β = 0.13, P < 0.01) and trabecular (β = 0.25, P < 0.001) volumetric bone mineral density and the bone strength index (β = 0.25, P < 0.001) of the tibia. Importantly, these relationships were generalized, as similar changes were present at the femur. Associations between physical activity and changes in bone parameters were weaker than those observed for muscle density. Nevertheless, physical activity was significantly (all P < 0.05) associated with greater gains in trabecular volumetric bone mineral density and the bone strength index of the distal femur. These findings suggest that poor muscle quality may put girls at risk for suboptimal bone development. Physical activity is associated with more optimal gains in weight-bearing bone density and strength in girls, but to a lesser extent than changes in muscle quality.

Childhood and adolescence are important periods for the accomplishment of healthy activities that provide a better growth of the human body. This study aimed to compare the anthropometric characteristics and muscular strength in girls aged between 9 and 11 years old that practice or do not physical exercises regularly. The data sample consisted of 40 girls, divided in two groups, 20 girls that practice physical exercises and 20 girls which do not practice it regularly. The children were evaluated through three tests of PROESD-BR, they are: lower limb strength, upper limb strength and abdominal resistance-strength; and also through anthropometric measurements: muscular mass, stature, skin folds, perimeters and diameters. For the statistical analysis, initially, the data normality and the homogeneity of the variances were verified through the tests Shapiro-Wilk and Levene. A teste t de student was done later to verify the differences among the groups. The results showed that in the anthropometric characteristics, only the fat percentage presented some difference among the groups, being more elevated in those non-practicing girls. In relation to the muscular strength tests, the practicing group showed increased levels in relation to strength. The group practicing regular exercise showed higher levels of muscle strength and a lower fat percentage when compared to non-practicing regular exercise.

&amp;lt;p&amp;gt;This study presents the results of the analysis of the effects of body composition on the&amp;lt;br /&amp;gt;manifestation of static strength in girls of lower elementary school age. The sample consisted&amp;lt;br /&amp;gt;of 63 girls aged seven. All the girls were from Subotica and attend elementary schools. Height&amp;lt;br /&amp;gt;was measured by the use of Martin&amp;amp;rsquo;s anthropometer, weight was measured by the use of InBody&amp;lt;br /&amp;gt;230. The measures of body composition (body fat, total body water and skeletal muscle mass)&amp;lt;br /&amp;gt;were assessed by InBody 230, a device which functions on the base of bioelectrical impedance.&amp;lt;br /&amp;gt;The static strength of arms and shoulder area was assessed by &amp;amp;bdquo;Bent-arm hang&amp;amp;rdquo; test. The results&amp;lt;br /&amp;gt;pointed to the statistically significant effects of the body composition on the manifestation of static&amp;lt;br /&amp;gt;strength in girls of lower elementary school age.&amp;amp;nbsp;&amp;lt;/p&amp;gt;

This study presents the results of the analysis of the effects of body composition on the manifestation of static strength in girls of lower elementary school age. The sample consisted of 63 girls aged seven. All the girls were from Subotica and attend elementary schools. Height was measured by the use of Martin's anthropometer, weight was measured by the use of InBody 230. The measures of body composition (body fat, total body water and skeletal muscle mass) were assessed by InBody 230, a device which functions on the base of bioelectrical impedance. The static strength of arms and shoulder area was assessed by 'Bent-arm hang' test. The results pointed to the statistically significant effects of the body composition on the manifestation of static strength in girls of lower elementary school age.

The influence of age at menarche on cross-sectional geometry of bone in young adulthood

The aim of this study was to assess physical fitness in 6- to 7-yr-old children and determine if there is any relationship between children's physical fitness, their urine iodine status, and their body-mass index (BMI). The studied population included 121 children from southern Poland. Physical fitness was measured using a physical fitness test for children age 3-7 yr. Urinary iodine concentrations were measured in the children's first urine output on waking using the modified PAMM (Program Against Micronutrient Malnutrition) method. Body height and weight were measured and BMI was calculated. The subjects were characterized by low physical fitness. Boys obtained better results in agility, power, and strength exercises (p ≤ .05). In girls, 11 correlation coefficients between the scores obtained in the physical fitness test, urinary iodine, and anthropometric measures were statistically significant, and in boys, only 2. BMI correlated positively with agility in girls and with strength in girls and boys. Our study revealed low physical fitness in Polish 6- to 7-yr-old children, which shows the need to implement programs aimed at increasing their physical activity. The relationship found between physical fitness and urine iodine status in girls indicates that future research in this area is needed.

Physical activity (PA) is critical for maximizing bone development during growth. However, there is no consensus on how well existing PA measurement tools predict bone strength. The purposes of this study were to compare four methods of quantifying PA (pedometer, 3-d PA recall (3DPAR), bone-specific PA questionnaire (BPAQ), and past year PA questionnaire (PYPAQ)), in young girls and to evaluate their ability to predict indices of bone strength. A total of 329 girls aged 8-13 yr completed a pedometer assessment, the 3DPAR, the BPAQ, and a modified PYPAQ. Peripheral quantitative computed tomography was used to assess bone strength index (BSI) at metaphyseal (4% distal femur and tibia) sites and strength-strain index (SSI) at diaphyseal (femur = 20%, tibia = 66%) sites of the nondominant leg. Correlations and hierarchical multiple regression were used to assess relationships among PA measures and indices of bone strength. After adjusting for maturity, correlations between PA measures and indices of bone strength were positive, although low (r = 0.01-0.20). Regression models that included covariates (maturity, body mass, leg length, and ethnicity) and PA variables showed that PYPAQ score was significantly (P < 0.05) associated with BSI and SSI at all sites and explained more variance in BSI and SSI than any other PA measure. Pedometer steps were significantly (P < 0.05) associated with metaphyseal femur and tibia BSI, and 3DPAR score was significantly (P < 0.05) associated with metaphyseal femur BSI. BPAQ score was not significantly (P > 0.05) associated with BSI or SSI at any sites. A modified PYPAQ that accounts for the duration, frequency, and load of PA predicted indices of bone strength better than other PA measures.

PURPOSE: The aim of this study was to evaluate the contribution of load, frequency, and duration of physical activity (PA) to bone geometry and strength in young girls. METHODS: 396 girls (aged 8-13 yrs) completed a modified past year physical activity questionnaire (PYPAQ), which inquires about the frequency and duration of leisure-time PA and sport participation. Load (peak strain score) values were assigned to each activity based on ground reaction force data. Scores were calculated for each PA component (load, frequency, duration) and for total PYPAQ score (load × frequency × duration). Peripheral quantitative computed tomography (pQCT) was used to assess bone parameters at the 4% and 20% distal femur and 4% and 66% distal tibia of the non-dominant leg. Structural and strength measures included total cross-sectional area (CSA) and bone strength index (BSI) at 4% sites and total CSA and strength-strain index (SSI) at 20% femur and 66% tibia sites. Partial correlations and multiple linear regression were used to examine the relationships among PA scores and bone parameters. Covariates included in all regression models were ethnicity, body mass, leg length, and maturity. RESULTS: Correlations between load, duration, total PYPAQ score and bone parameters were significant (P < 0.05), yet low (r = 0.10-0.22). Frequency was not significantly (P > 0.05) correlated with bone parameters. Regression analyses showed that load was significantly (P < 0.05) and independently associated with 4% femur total CSA, 4% tibia BSI, and 66% tibia total CSA, while duration was significantly (P < 0.05) associated with 20% femur SSI, 4% tibia BSI, and 66% tibia total CSA and SSI. Total PYPAQ score derived from load, frequency, and duration, was significantly (P < 0.05) associated with all bone parameters, except 4% femur total CSA, and explained more variance in bone parameters as compared to any individual component. CONCLUSION: Our findings suggest that although PA load and duration are associated with bone geometry and strength, their influence is modest and site specific. Total PYPAQ score is a stronger predictor of bone geometry and strength than any individual PA component. Longitudinal data are needed to determine whether these influences track through puberty. Supported by NIH Grant: HD050775.