RESUMO
OBJECTIVE: To explore the influence of secular trends in body height and weight on the prevalence of overweight and obesity among Chinese children and adolescents. METHODS: The data were obtained from five cross-sectional Chinese National Surveys on Students' Constitution and Health. Overweight/obesity was defined as BMI-for-age Z-score of per the Wold Health Organization (WHO) reference values. Body height and weight for each sex and age were standardized to those reported in 1985 (standardized height: SHY; standardized weight: SWY) and for each sex and year at age 7 (standardized height: SHA; standardized weight: SWA) using the Z-score method. RESULTS: The prevalence of overweight/obesity in Chinese children was 20.2% among boys and 10.7% among girls in 2010 and increased continuously from 1985 to 2010. Among boys and girls of normal weight, SHY and SHA were significantly greater than SWY and SWA, respectively (P < 0.001). Among boys and girls with overweight/obesity, SHY was significantly lower than SWY (P < 0.001), and showed an obvious decreasing trend after age 12. SHA was lower than SWA among overweight boys aged 7-8 years and girls aged 7-9 years. SHY/SHW and SHA/SWA among normal-weight groups were greater than among overweight and obese groups (P < 0.001). CONCLUSION: The continuous increase in the prevalence of overweight/obesity among Chinese children may be related to a rapid increase in body weight before age 9 and lack of secular increase in body height after age 12.
Assuntos
Estatura , Peso Corporal , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Adolescente , Criança , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Sobrepeso/etiologia , Obesidade Infantil/etiologia , PrevalênciaRESUMO
OBJECTIVE: To analyze the awareness rate of obesity risk factors among children and adolescents, and to provide the basis for preventing their obesity. METHODS: The students selected by using stratified cluster sampling method, were measured for the body height, weight, and waist circumference, and were surveyed for the awareness rate of obesity risk factors by using the questionnaire. The distribution characteristics of awareness on obesity risk factors were analyzed. RESULTS: The awareness rate of obesity risk factors was 74.1%, and there was no significant difference on the awareness rate of obesity risk factors between the males [71.2% (247/347)] and females [77.2% (257/333)], the abdominal obesity students [73.5% (202/275)] and non-abdominal obesity students [74.6% (302/405)], the overall obesity students [74.3% (185/249)] and non-overall obesity students [74.0% (319/431)], respectively. However, the awareness rate of obesity risk factors among the primary school students was 81.9% (272/332) that was higher than that of the middle school students [66.7% (232/348)] (P<0.05). Compared with the primary school students, the non-awareness risk of obesity risk factors would increase among the middle school students (OR=2.23, P<0.05). CONCLUSION: The overall awareness rate of obesity risk factors is not high among children and adolescents, especially among middle school students.
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Conhecimentos, Atitudes e Prática em Saúde , Obesidade/epidemiologia , Adolescente , Estatura , Peso Corporal , Criança , Feminino , Humanos , Masculino , Obesidade Abdominal/epidemiologia , Fatores de Risco , Instituições Acadêmicas , Estudantes , Inquéritos e Questionários , Circunferência da CinturaRESUMO
OBJECTIVE: The purpose of this study was to explore an objective measure to assess actual body shape of children and adolescents in China. METHODS: Based on the Chinese National Survey on Student's Constitution and Health (CNSSCH) in 2005, 210 927 children and adolescents' (7-18 years) body height, body weight, chest circumference, sitting height, chest circumference-height ratio, chest circumference-sitting height ratio, chest circumference-low limb ratio, and sitting height-low limb ratio measurements were used to develop an objective measure by using transformation variables and explored factor analysis (EFA). Discrimination power of the objective measure was evaluated based on BMI reference and Receiver Operating Characteristic curves (ROC). RESULTS: The objective measure included four dimensions scores: transverse dimension (TD) indicating weight and chest circumference; length dimension (LD) indicating height and sitting height; transverse-length ratio dimension (TLD) indicating chest circumference-height ratio, chest circumference-sitting height and chest circumference-low limb ratio; proportion dimension (PD) indicating sitting height-low limb ratio. The whole dimension (WD) indicating the whole body shape was showed by the average of four dimensions scores. Four dimensions and WD scores were approximately 80 in children and adolescents with normal weight, and higher than those of overweight, obesity, and underweight (all P-values <0.001). Areas under ROC of overweight and obesity compared with normal weight ranged from 0.88 to 1.00 for scores of TD, TLD, and WD. CONCLUSION: The objective measure which included four dimensions was explored, and TD, TLD, and WD had significant discrimination power.
Assuntos
Estatura , Tamanho Corporal , Peso Corporal , Povo Asiático , Índice de Massa Corporal , Criança , China , Feminino , Humanos , MasculinoRESUMO
OBJECTIVE: To categorize growth and development stages among children and adolescents based on height, and to explore the influences of diet behaviors on height during different growth and development stages. METHODS: Children and adolescents (7 to 18 years) with normal weights were selected using "Reference Norm for Screening Overweight and Obesity in Chinese Child and Adolescent" set up by WGOC in 2003 and "Reference Norm for Screening Underweight in Chinese Child and Adolescent" from the "2010 National Physical Fitness and Health Surveillance" data, and the variables of height and diet behaviors sorted. The growth and development stages were categorized using the hierachical cluster analysis, and the multilevel model was used to analyze influences of diet behaviors on height at different growth and development stages. RESULTS: Basis on height, there were 4 growth and development stages among the children and adolescents. In the boys, growth and development stages included Pre-GSS (growth spurt stage, GSS) including 7 to 10 years, GSS (11 to 12 years), Post-GSS (13 to 14 years), and growth stability stage (15 to 18 years); in the girls, the stages included the fast velocity GS (growth stage, GS) including 7 to 10 years, GS (11 to 12 years), Post-GS (13 to 15 years), and growth stability stage (16 to 18 years). The results of the multilevel model showed that the students' height in the urban areas were higher than in the rural areas (P<0.01), and the trend of difference between the urban and rural areas with the different growth stages was a parabola shape, the highest differences were 3.36 cm and 3.23 cm in the GSS and the fast velocity GS, respectively. There were significant influences of breakfast on height during the Pre-GSS and the fast velocity GS (P<0.01), and increased 0.40 cm and 0.57 cm, respectively. Excluding the stablility growth stage in the girls, drinking milk increased significantly height during the different growth stages (P<0.01), and the increases were gradual downtrend with the growth stages, the highest increase was 0.91 cm and 0.94 cm in Pre-GSS and the fast velocity GS, respectively. Eating eggs increased significantly height during all the growth stages (P<0.01), and the increases were the gradual uptrend with different growth stages. There were interaction effects among breakfast, drinking milk and eating eggs during the different growth stages, which was the gradual downtrend. CONCLUSION: Breakfast and drinking milk are conducive to growth during early adolescence, and the effect of eating eggs on growth is gradual uptrend with different growth stages.
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Estatura , Dieta , Adolescente , Animais , Povo Asiático , Criança , China , Ovos , Feminino , Humanos , Masculino , Leite , Modelos Estatísticos , Análise Multinível , EstudantesRESUMO
OBJECTIVE: To explore the association between spermatorrhea and physical development during puberty for boys aged 11 to 15 years old in China. METHODS: The height, weight, chest circumference, waist circumference, hip circumference and the station of spermatorrhea of boys aged 11-15 years old were selected from the data of 2010 National Survey on Students Constitution and Health. Body mass index (BMI) and waist to height ratio were calculated. After 1: 1 random matching in every 0.1 year of age, 6880 boys (3440 with spermatorrhea and 3440 without spermatorrhea) were included in our study. t-test was used to analyze differences in anthropometry measurements between boys with spermatorrhea and boys without spermatorrhea in each age group. Multilevel model was used to analyze the relationship between anthropometry measurements and spermatorrhea. RESULTS: A total of 6880 boys were put in this research. Heights of boys with spermatorrhea aged 11 to 15 years old were (150.96 ± 8.01), (159.46 ± 8.03), (163.76 ± 7.43), (167.03 ± 7.12) and (169.50 ± 6.64) cm, respectively, while heights of boys without spermatorrhea aged 11 to 15 were (147.38 ± 6.54), (153.55 ± 8.68), (160.35 ± 8.66), (164.44 ± 7.98) and (167.98 ± 7.80) cm, respectively. The differences were significant (t values were 3.70, 9.96, 10.76, 8.26, and 3.21 respectively with all P values < 0.01). RESULTS: of multilevel analysis showed that the differences of weight were the largest from 11 to 13 years old, boys with spermatorrhea having a 4.20, 7.23 and 3.93 kg (Waldχ(2) values were 13.11, 70.73 and 72.93 respectively, all P values < 0.01) larger weight than boys without spermatorrhea, respectively. Differences of height were the largest from 14 to 15 years old, boys with spermatorrhea having a 2.81 and 1.99 cm (Waldχ(2) values were 87.80 and 19.54, P < 0.01) larger height than boys without spermatorrhea. The trends of the differences between boys with spermatorrhea and boys without spermatorrhea (ß value) with age were parabolic on weight, BMI, height, chest circumference, waist circumference, hip circumference and waist to height ratio. The ß values reached maximum at 12 years old, which were 7.23 kg, 1.64 kg/m(2), 5.55 cm, 4.40 cm, 4.63 cm, 4.94 cm, and 0.015, respectively. The ß values reached minimum at 15 years old, which were -0.39 kg, -0.56 kg/m(2), 1.99 cm, -0.57 cm, -1.59 cm, -0.42 cm and -0.015, respectively. CONCLUSION: There is an association between spermatorrhea and physical development among boys aged 11 to 15 years in China , which has a parabolic trend with age.
Assuntos
Desenvolvimento do Adolescente , Desenvolvimento Infantil , Doenças dos Genitais Masculinos/epidemiologia , Adolescente , Índice de Massa Corporal , Pesos e Medidas Corporais , Criança , China/epidemiologia , Humanos , MasculinoRESUMO
OBJECTIVE: To investigate the association between early age at menarche and blood pressure in Chinese girls aged 7 to 17 years. METHODS: A total of 76 869 girls aged 7 to 17 years old were selected from the national physical fitness and health research in 2010, and probit analyses were used to calculate the average age of menarche for each province. Girls whose age were lower than the P 10 of age at menarche were judged as early age at menarche, and matched with two selected participant without menarche based on the age and the same urban or rural areas. High blood pressure was defined as whose systolic pressure and/or diastolic pressure was higher than P 95 of systolic pressure or diastolic pressure at the same age group. The difference of the rate of high blood pressure in girls with and without menarche by Chi-square test, and multilevel model was used to analyze the relationship between early age at menarche and blood pressure. RESULTS: In 76 869 girls, the values of height and BMI were separately (152.2 ± 10.4) cm and (18.7 ± 3.1) kg/m(2), while the systolic pressure and diastolic pressure were (103.4 ± 11.0) mm Hg (1 mm Hg = 0.133 kPa) and (65.0 ± 9.1) mm Hg respectively. In 47 942 girls (62.4%) had occurred menstruation while 28 927 girls (37.6%) without menstruation. The girls began to report menstruation at the age of 9, and 81.5% (7123/8736) girls had already reported menstruation at the age of 13. The rate of high blood pressure in menstruation group from 11 to 13 years were separately 6.71% (100/1490), 5.99% (265/4423) and 5.38% (383/7123), which was significant higher than 3.78% (265/7005), 3.33% (144/4328) and 4.09% (66/1613) in the same age group of non-menstruation (the values of Chi-square were separately 25.62, 32.36, 4.46, and all P values < 0.05) . The mean age of early age at menarche was 9 to 11 years old, and the rate of high blood pressure, high systolic pressure, and high diastolic pressure at 11 years group was separately 6.08% (49/806), 4.84% (39/806) and 3.35% (27/806), which was significant higher than that in non-menstruation group (separately 3.11% (50/1607), 2.30% (37/1607) and 1.43% (23/1607), and the values of Chi-square were separately 12.02, 11.32 and 9.74, while all P values <0.01). After adjusted by region and age, early age at menarche were separately associated with the rate of high blood pressure (OR = 2.188; 95%CI: 1.254-3.818), high systolic pressure (OR = 1.925; 95%CI:1.097-3.379) and high diastolic pressure (OR = 2.088; 95%CI: 1.072-4.065). CONCLUSION: Early age at menarche may be one of the influence factors of high blood pressure, which may contribute to early age of high blood pressure in Chinese children and adolescents.
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Fatores Etários , Menarca , Adolescente , Pressão Sanguínea , Criança , China/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Modelos EstatísticosRESUMO
OBJECTIVE: To analyze the association between abdominal obesity and blood pressure among 7-10 years old Chinese children. METHODS: A total of 40 495 children aged 7-10 years with complete height, weight, waist circumference and blood pressure data were chosen from the data of 2010 Chinese National Survey on Students Constitution and Health. Based on the "Reference Norms for Screening Overweight and Obesity in Chinese Children and Adolescents" developed by Working Group Obesity in China (WGOC) and the waist to height ratio reference value for children (WHtR ≤ 0.46) , the children were divided into 4 body types (normal weight, simple abdominal obesity, combined obesity and other types). High blood pressure was defined as the systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) higher than the P 95 blood pressure value of 2010 national student of the same gender and age. The prevalence of simple abdominal obesity, combined obesity and high blood pressure were described. Three groups (with 2165 children in each) of children with normal weight, simple abdominal obesity, combined obesity respectively were selected from the chosen ones matched by gender, age (within ± 0.5 years old) and height (within ± 0.3 cm) at the ratio of 1: 1: 1. The value of blood pressure and prevalence of high blood pressure were described.χ(2) test, analysis of variance and multilevel models were used to analyze the relationship between obesity and blood pressure. RESULTS: A total of 40 475 children were selected from the database, including 20 175 boys and 20 320 girls. The prevalence of simple abdominal obesity was 6.36% (2576/40 495), the prevalence of boys and girls was 7.41% (1494/20 175) and 5.32% (1082/20 320) respectively. The prevalence of combined obesity was 16.33% (6611/40 495), the prevalence of boys and girls was 21.30% (4298/20 175) and 11.38% (2313/20 320) respectively. There were statistical differences in the body type distribution of both boys and girls (χ(2) = 869.01, P < 0.01). The prevalence of high blood pressure was 9.62% (3896/40 495), the prevalence of boys (10.05% (2028/20 175)) was higher than girls (9.19% (1868/20 320)) (χ(2) = 8.59, P < 0.01). The value of SBP and DBP among combined obesity group (boys: (103.8 ± 11.3), (64.7 ± 10.1) mm Hg (1 mm Hg = 0.133 kPa); girls: (102.9 ± 12.1), (64.5 ± 10.0) mm Hg) > simple abdominal obesity group (boys: (99.5 ± 11.2), (61.6 ± 9.9) mm Hg; girls: (99.6 ± 11.4), (62.6 ± 9.3) mm Hg)> normal weight group (boys: (97.4 ± 10.8), (60.5 ± 9.4) mm Hg; girls: (97.2 ± 10.8), (60.8 ± 9.4) mm Hg), and the differences were statistical significant (Fboys: 113.22, 62.05; Fgirls: 54.19, 32.31, P < 0.01). According to the results of multilevel model, among boys, compared with the normal weight group, the SBP of combined obesity group and simple abdominal obesity group was 6.0 and 1.8 mm Hg higher respectively (Wald χ(2): 17.55, 204.94, P < 0.01); the DBP was 4.0 and 0.9 mm Hg higher respectively (Wald χ(2): 6.37, 114.05, P < 0.05). Among girls, the SBP was 5.0 and 2.1 mm Hg higher respectively (Wald χ(2):16.47, 92.52, P < 0.01); the DBP was 3.5 and 1.6 mm Hg higher respectively (Wald χ(2): 12.29, 57.52, P < 0.01). Comparing with normal group, the risk of high SBP among boys with simple abdominal obesity was higher (OR = 1.48; 95%CI: 1.06-2.06), and both the boys (SBP: OR = 3.06; 95%CI: 2.28-4.11) ; DBP: OR = 2.72; 95%CI: 1.99-3.72) and girls (SBP: OR = 2.48; 95%CI: 1.75-3.53; DBP: OR = 2.64; 95%CI: 1.82-3.93) in combined obesity group had a higher risk of high SBP and high DBP. CONCLUSION: Simple abdominal obesity is associated with the increasing of blood pressure in children, and combined obesity has a closer ties than simple abdominal obesity.
Assuntos
Hipertensão/epidemiologia , Obesidade Abdominal/epidemiologia , Obesidade Infantil/epidemiologia , Pressão Sanguínea , Índice de Massa Corporal , Criança , China/epidemiologia , Feminino , Humanos , MasculinoRESUMO
OBJECTIVE: To explore the association between early menarche with anthropometry measurements among adolescent girls in China. METHODS: Research material was selected from the data of 2010 Chinese National Surveys on Students Constitution and Health. Probability unit regression method was used to calculate the age of 10th percentile (P 10) at menarche and menarche age before the P 10 was defined as early menarche(9.0-11.6 years old). A total of 1072 girls with early menarche were screened. Each girl with early menarche was frequency matched with two girls who hadn't achieved menarche and with the age difference less than 0.1 yr and from the same urban or rural locations. A total of 2144 girls without menarche were screened. Participants' data of height, weight, sitting height, chest circumference, body mass index(BMI) and height and sitting height index were analyzed. t test and wilcoxon test were used to analyze the anthropometry measurements differences between the two groups, Chi square test was used to analyze the differences of overweight and obesity between the two groups. Multilevel model was used to explore the association between early menarche with anthropometry measurements and overweight and obesity. RESULTS: A total of 1072 girls with early menarche and 2144 girls without menarche. Early menarche girls' height, sitting height, chest circumference, weight and BMI were (151.42 ± 7.46) cm, (80.86 ± 4.21) cm, (73.88 ± 7.72) cm, (44.32 ± 9.35) kg, and (19.18 ± 3.03) kg/m(2), while they were (144.86 ± 7.55) cm, (76.96 ± 4.05) cm, (67.25 ± 6.94) cm, (36.07 ± 7.88) kg and (16.64 ± 2.48) kg/m(2) in girls without menarche. The difference between two groups were significant(Z values were -22.20, -23.69, -24.38, -23.12, -20.17, -6.33 respectively with all P values < 0.01). Multilevel analysis results showed that in 9.0-11.6 years old girls early menarche was associated with anthropometry measurements(all P values < 0.05). Compared with girls without menarche, girls with early menarche had a relative higher height, sitting height, weight, chest circumference, with increments of 5.28 cm, 3.37 cm, 5.53 cm, 6.37 kg, 1.79 kg/m(2). Within subgroup analysis, there were parabolic trends with age in the height, weight and sitting height differences and "U" trend in chest circumference difference between girls with early menarche and girls without menarche.In 9.0-10.8 years old, 10.9-11.0 years old and 11.1-11.2 years old groups, the risk of overweight and obesity among girls with early menarche were 2.98 (95%CI:1.92-4.63) times, 6.76 (95%CI:2.79-16.39) times, 2.99 (95%CI:1.40-6.40) times of girls without menarche. CONCLUSION: The early onset of menarche is related with height, sitting height, weight and chest circumference, and it is closely associated with overweight and obesity among adolescent girls in China.
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Desenvolvimento Infantil , Menarca , Índice de Massa Corporal , Criança , China/epidemiologia , Feminino , Humanos , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologiaRESUMO
OBJECTIVE: To explore the influencing factors on physical endurance among Chinese primary and middle school students aged 10-17. METHODS: Data was used from "2010 National Physical Fitness and Health Surveillance", from which 68 458 primary and middle school students with complete information were selected. Good physical endurance was defined as endurance running time ≤ P 25 of same gender and age, poor physical endurance as ≥ P 75 of same gender and age. Difference of endurance running time in different physical endurance groups was compared; chi-square test, logistic regression and multiple level model were used to analyze influence of region, BMI, diet, exercise and exercise willingness on physical endurance. RESULTS: There were 34 293 (50.0%) students of good physical endurance and 34 219 (50.0%) ones of poor physical endurance in 68 458 subjects. Percentage of good physical endurance was 53.8% (18 285/33 996) in rural students, higher than urban ones (46.3% (15 954/34 462)) (χ(2) = 384.16, P < 0.01). Percentage of good physical endurance was 12.2% (448/3660) in obese students, lower than normal (55.2% (28 183/51 028)), overweight (29.3% (2012/6874)) and emaciated ones (52.1% (3596/6896)) (χ(2) = 3840.08, P < 0.01). Percentage of good physical endurance was 52.5% (25 534/48 679) in students having breakfast everyday, higher than ones never having breakfast or 1-2 times per week (41.3% (3209/7768))(χ(2) = 438.31, P < 0.01). Percentage of good physical endurance was 51.7% (11 580/22 379) in students having milk everyday, slightly higher than ones never or sometimes having milk (49.2% (22 659/46 079)) (χ(2) = 39.84, P < 0.01). Percentage of good physical endurance was 55.3% (18 961/34 314) in students with adequate physical education class, higher than ones with inadequate class (44.7% (15 278/34 144)) (χ(2) = 756.41, P < 0.01). Percentage of good physical endurance was 58.6% (9484/16 195) in students with one hour exercise or more per day, higher than ones with less than one hour exercise (47.4% (24 755/52 263)) (χ(2) = 619.82, P < 0.01). Percentage of good physical endurance was 60.1% (19 287/32 118) in students who were "very willing" to take part in endurance running, higher than "generally willing" ones (45.4% (10 569/23 272)) and "not willing" ones (33.5% (4383/13 068)) (χ(2) = 2909.61, P < 0.01). Multiple level analysis revealed that risk of poor physical endurance was lower in rural students (OR = 0.80, 95%CI: 0.77-0.82) than urban ones. Risk in emaciated students (OR = 1.11, 95%CI: 1.05-1.17), overweight students (OR = 2.69, 95%CI: 2.55-2.85) and obese students (OR = 7.71, 95%CI: 6.97-8.52) was higher than normal ones. Concerning diet, risk of poor physical endurance in students never having breakfast or once to twice per week was highest (OR = 1.20, 95%CI: 1.13-1.26), followed by students having breakfast three to five times per week (OR = 1.13, 95%CI: 1.08-1.18); risk in students having one bag of milk per day was higher (OR = 1.09, 95%CI: 1.02-1.17) than ones having two bags. Concerning exercise, risk of poor physical endurance in students with inadequate physical education class (OR = 1.20, 95%CI: 1.13-1.26) and less than one hour exercise per day (OR = 1.34, 95%CI: 1.29-1.40) was higher than ones with adequate physical education class and one hour exercise or more respectively. Risk of poor physical endurance in students who were "generally willing" (OR = 1.67, 95%CI: 1.61-1.73) and "not willing" (OR = 2.72, 95%CI: 2.60-2.85) to take part in endurance running was higher than "very willing" ones. CONCLUSION: Urban and rural residence, BMI, breakfast, milk, physical education class, exercise time and exercise willingness were related to primary and middle school students'physical endurance.
Assuntos
Modelos Estatísticos , Resistência Física , Aptidão Física , Adolescente , Criança , Feminino , Humanos , Masculino , EstudantesRESUMO
OBJECTIVE: To explore the association between early menarche and physical fitness among adolescent girls in China. METHODS: Research material was selected from the data of "2010 National Physical Fitness and Health Survey". Probability unit regression method was used to calculate the age of 10th percentile at menarche and menarche age before the 10th percentile was defined as early menarche(9.0-11.6 years old). A total of 1072 girls with early menarche were selected. Each girl with early menarche was matched with one girl from the same urban or rural locations who hadn't achieved menarche with the age difference less than 0.1 years. A total of 1072 girls without menarche were selected. Indicators of physical fitness included 50 m running, standing broad jump, 50 m×8 shuttle running and sit-ups. Differences of physical fitness between early menarche and without menarche were analyzed using t test stratified by age and urban/rural area. The multilevel models of single dependent variable and multiple dependent variables were used to analyze association between early menarche and physical fitness. RESULTS: A total of 2144 students were put in this research. Among girls (11.0-11.6 years old) in urban areas, 50 m running, standing broad jump and sit-ups was (9.78 ± 0.85) s, (153.81 ± 18.59) cm, and 27.79 ± 10.25, respectively for those with early menarche, while in girls without menarche was (10.01 ± 0.90) s, (149.71 ± 18.72) cm and 26.28 ± 10.11, respectively. There were significant differences between two groups on all above variables (t values were 4.02, 3.43 and 2.31, respectively with all P values <0.01). Among girls in rural, 50 m×8 shuttle-running and sit-ups was (125.22 ± 15.57) s and 24.96 ± 8.97 for those with early menarche, while it was (120.92 ± 13.06) s and 22.96 ± 9.83 for those without menarche. There were significant differences between two groups on both variables(t values were 3.89 and 2.77 with both P values < 0.01). In addition, 50 m×8 shuttle-running in girls (10.0-10.9 years old) with early menarche was (128.52 ± 15.74) s and it was (123.89 ± 13.50) s in girls without menarche. The difference was significant (t = 2.14, P < 0.05). The multilevel analysis showed that 50 m running, standing broad jump and sit-ups in girls with early menarche was 0.12 s, 3.14 cm and 1.11 higher than girls without menarche (Waldχ(2) values were 4.00, 6.22 and 4.07, respectively with all P values < 0.05). But 50 m×8 shuttle-running in girls with early menarche was 1.95 s less than girls without menarche (Waldχ(2) = 3.96, P < 0.05). CONCLUSION: Early menarche may be associated with higher speed fitness, leg power and muscle power and lower physical stamina.
Assuntos
Menarca/fisiologia , Aptidão Física/fisiologia , Criança , China , Feminino , Humanos , Modelos Estatísticos , População Rural , Estudantes , População UrbanaRESUMO
OBJECTIVE: To analyze the influence of overweight and obesity on body function among children and adolescents using a multilevel model, and to provide the basis for understanding their influence. METHODS: According to the "Reference Norms for Screening Overweight and Obesity in Chinese Children and Adolescents" set up by Working Group Obesity in China (WGOC) in 2003, we screened out individuals with overweight and obesity from the data obtained from the body and health survey of Chinese children and adolescents in 2005. The samples of the non-overweight group and the overweight group were randomly selected from the screened data by 1:1 match with samples of the obesity group by gender and city/rural area, then underwent the multilevel model to explore the influence of overweight and obesity on body function. RESULTS: The single dependent variable model showed that the overweight group had significant increases in systolic blood pressure (SBP) and diastolic blood pressure (DBP) by 5.25 mmHg (1 mmHg=0.133 kPa) and 3.44 mmHg, respectively (P<0.01), when compared with the non-overweight group. There were no significant differences between the overweight and non-overweight groups in pulse and vital capacity (VC) (P>0.05), and the obesity group had significant increases in SBP, DBP, pulse and VC by 10.15 mmHg, 6.34 mmHg, 1.44 times/min and 390.04 mL, respectively (P<0.01), when compared with the non-overweight group. The multiple dependent variables model showed that the SBP, DBP and pulse of the overweight group and obesity group were significantly greater than those of non-overweight group (P<0.01). There was a significant difference between the overweight group and non-overweight group in VC (P<0.05), yet the same result was not found between the obesity group and non-overweight group (P>0.05). CONCLUSION: Overweight and obesity may cause a decline in body function among children and adolescents, and obesity has a more obvious influence on body function.
Assuntos
Pressão Sanguínea/fisiologia , Análise Multinível , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos de Amostragem , Capacidade Vital/fisiologiaRESUMO
OBJECTIVE: To study the effects of overweight and obesity on physical function (including systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse, weight vital capacity index) in children and adolescents. METHODS: The data of 2010 Chinese National Survey on Students Constitution and Health was analyzed. The samples of overweight and normal-weight group were randomly selected from the data by matching gender, urban or rural for getting the same number sample size as obese group (10 601 each group). The students aged 7 - 18 years were classified into 3 groups by BMI percentiles (P5, P15, P25, P50, P75, P85 and P95), to analyze the change of physical function along with BMI percentile. RESULTS: Compared to the normal-weigh group, SBP of the obese boys of all age groups increased by 8.0 - 12.0 mm Hg, DBP increased by 4.7 - 5.9 mm Hg, while SBP of the obese girls increased by 7.5 - 11.6 mm Hg, DBP increased by 4.7 - 6.1 mm Hg, with statistical significance (P < 0.05). In 13 - 15-year group, pulse of obese boys was 0.8 times/min higher than that of normal-weight. In 16 - 18-year group, pulse of obese boys was 1.1 times/min higher than that of overweight or normal-weight, while pulse of obese girls were 1.5 and 1.7 times/min higher than that of overweight and normal-weight, respectively (P < 0.05). Pulses in boys aged 7 - 9 years when BMI were P5, P50, P(95) were 87.63, 87.00, 87.83 times/min, and pulses in boys aged 10 - 12 were 85.66, 85.30, 85.43 times/min, respectively. Pulses in boys aged 13 - 15 years when BMI were P5, P50, P95 were 82.60, 81.39, 82.34 times/min, and pulses in boys aged 16 - 18 years were 80.15, 79.00, 79.98 times/min. In both boys and girls of all age groups, weight vital capacity index had the trend of obese < overweight < normal-weight (P < 0.05). Compared to the normal-weight group, weight vital capacity index of overweight boys decreased by 6.4 - 8.4 ml/kg, that of obese boys decreased by 11.9 - 14.8 ml/kg, while that of overweight girls decreased by 5.3 - 7.7 ml/kg, that of obese girls decreased 11.0 - 11.5 ml/kg. CONCLUSION: Compared to the normal-weight, overweight and obese children and adolescents had elevated blood pressure, increased pulse, decreased weight vital capacity index.
Assuntos
Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Adolescente , Criança , China/epidemiologia , Etnicidade , Feminino , Humanos , Masculino , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Fatores de Risco , EstudantesRESUMO
OBJECTIVE: The aim of this study was to analyze the mediating effect of body dissatisfaction in correlation between obesity and dietary behavior changes for weight loss (DBCWL). METHODS: A total of 680 primary and middle school students were included in this study. Their body height, weight, and waistline were effectively measured, and they were also evaluated to assess their body dissatisfaction, perception of dietary behaviors, and DBCWL. The correlation among these factors was analyzed using mediating effect models. RESULTS: The prevalence of overweight/obesity and abdominal obesity was significantly higher in males than in females (P < 0.05). Overweight/obesity, abdominal obesity, and body dissatisfaction significantly increased the risk for DBCWL (OR = 2.57, 2.77, and 1.95, respectively). Overweight/obesity and abdominal obesity significantly increased the risk for body dissatisfaction (OR = 6.00 and 4.70, respectively). Significant mediating effects of body dissatisfaction were observed in correlation between overweight/obesity and DBCWL and between abdominal obesity and DBCWL (OR = 2.20 and 1.92, respectively; P < 0.05), and the proportions of mediating effects among the total effects were 48.89% and 46.60%, respectively. CONCLUSION: Body dissatisfaction might play an important mediating effect in association between DBCWL and obesity, which indicates that guiding children to correctly recognize their body might be more conducive than promoting obese children toward weight loss through dietary behavior changes.