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L B Andersen

Publications and source records attributed to L B Andersen.

At least 19 recordsLinked to original sources

Peripheral bone mineral density and different intensities of physical activity in children 6-8 years old: the Copenhagen School Child Intervention study.

This study aimed to evaluate the association between objectively measured habitual physical activity and calcaneal and forearm bone mineral density (BMD, g/cm(2)), one mechanically more loaded and one less loaded skeletal region, in children aged 6-8 years. BMD was measured in 297 boys and 265 girls by peripheral dual-energy X-ray absorptiometry in the forearm and calcaneus. An accelerometer registered the level of physical activity during 4 days (2 weekdays and the weekend). Weight, height, and skinfold thickness were measured. In order to establish thresholds (count . min(-1)) for bone-stimulating physical activity, we evaluated different definitions of vigorous physical activity. The boys had 3.2% higher distal forearm bone mineral content (BMC, P < 0.001) and 4.5% higher distal forearm BMD (P < 0.001) than the girls. They also carried out 9.7% more daily physical activity and spent 14.6-19.0% more time in vigorous physical activity (all P < 0.05) compared to the girls. In contrast, the girls had 3.8% higher calcaneal BMC (P < 0.01) and 2.5% higher calcaneal BMD (P < 0.05) than the boys. Both calcaneal and forearm BMD were significantly related to total time of daily physical activity as well as with intense physical activity above all the chosen cut-off points (all P < 0.05). The beta value for mean count . min(-1) physical activity was significantly lower than that for all the chosen cut-off points of vigorous activity both for calcaneal and distal forearm BMD. This study suggests that both habitual daily physical activity and amount of vigorous physical activity in children aged 6-8 years are associated with appendicular BMD.

Absorptiometry, Photon↗

Secular trends in cardiorespiratory fitness and body mass index in Danish children: The European Youth Heart Study.

AIM: To examine the secular trends in cardiorespiratory fitness (CF) and body fatness in Danish children. Trends were analyzed overall and across socioeconomic status (SES). METHODS: Two cross-sectional studies conducted on 589 and 458 third-grade Danish children in 1997-1998 and 2003-2004, respectively. CF was determined by a maximal cycle-ergometer test. The lowest sex-specific quartile of CF in the study from 1997 to 1998 was used as a cut-point for low CF. Body mass index (BMI) cut-points were used to describe overweight, and SES was divided into two groups according to parents' occupation. RESULTS: This study showed a secular decline in CF in girls overall. Increased CF, BMI, and prevalence of overweight were observed in boys with high SES, in boys with low SES, and in girls with low SES, respectively. However, after additional Bonferroni's correction, none of the statistical analyses performed across socioeconomic gradients reached significant P-values. CONCLUSION: CF declined in girls overall. Although not statistically significant after additional Bonferroni's correction, results in general showed less favorable trends in low SES children. Thus, trying to describe secular trends in CF and body fatness overall without any regard to SES might disguise social-caused differences. However, further studies are needed in order to verify this hypothesis.

Body Mass Index↗

Sex differences in bone size and bone mineral density exist before puberty. The Copenhagen School Child Intervention Study (CoSCIS).

BACKGROUND: The aim of this study was to provide normative data of bone mineral density (BMD; g/cm(2)) of the forearm and the calcaneus, evaluated by peripheral dual X ray absorbtiometry (DXA), in children aged 6 to 7 years of age and to evaluate the association with anthropometrics and sex. MATERIAL AND METHODS: 368 boys and 326 girls with a mean age of 6.7 +/- 0.4 years participated. BMD was measured by DXA in the forearms and the os calcanei, with average values presented in this report. Measurements of weight, height, skinfolds, the width of distal radius and ulna, and the femur condyles were collected and body composition estimated from skinfolds measurements. RESULTS: There was no difference in calcaneus BMD when comparing boys and girls, whereas the boys had 4.5% (0.013 g/cm(2)) higher forearm BMD than the girls (P < 0.001). Calcaneal BMD (mean 0.318 g/cm(2)) was 11% higher than forearm BMD (mean 0.283 g/cm(2)). Linear relationship was found between calcaneus BMD and weight (partial r = 0.50), Fat free mass (FFM) (partial r = 0.50), Fat mass (FM) (partial r = 0.45), % body fat (partial r = 0.29) and knee width (partial r = 0.46), all P < 0.000 respectively. Adjusted for weight the relationship between calcaneus BMD and FFM, FM, %body fat and knee width disappeared. There were significant relationships between the forearm BMD and weight (partial r = 0.37), FFM (partial r = 0.39), FM (partial r = 0.28), %body fat (partial r = 0.14) and wrist width (partial r = 0.24), all P < 0.000 respectively. Adjusted for body weight, the relationship remained between forearm BMD and FFM (r = 0.10), FM (R = -0.10) and % body fat (r = -0.12), all P < 0.000 respectively. Children measured in the spring had 3.5% (P < 0.01) higher calcaneus BMD than children measured in the winter. CONCLUSION: Seven year old boys have higher BMD in the forearm but not in the calcaneus in comparison with girls of a similar age. Body weight is the best predictor of calcaneus BMD, accounting for 25% of the variance whereas body weight and FFM are the best predictors of forearm BMD, each accounting for 17% of the variance, respectively.

Absorptiometry, Photon↗

Daily physical activity related to body fat in children aged 8-11 years.

OBJECTIVE: To evaluate the association between objectively measured daily physical activity and body fat. STUDY DESIGN: Cross-sectional, observational, study of 248 children aged 7.9 to 11.1 years. Abdominal fat mass and total body fat mass were measured by dual-energy X-ray absorptiometry. Daily physical activity was assessed by accelerometers for 4 days. RESULTS: Total body fat expressed as a percentage of body mass was inversely related to minutes of vigorous physical activity per day, for all children r = -0.38 (P < .05). Children, both boys and girls, in the highest quartile of body fat performed on average 12 minutes less vigorous activity per day compared with their counterparts in the lowest quartile. Multiple regression analysis revealed that independent factors for body fat were number of minutes of vigorous activity per day and sex. CONCLUSION: Low physical activity can be a contributing factor in childhood obesity. Only longitudinal studies, however, can give more definitive information about the relation between daily physical activity and obesity.

Absorptiometry, Photon↗

Daily physical activity in Swedish children aged 8-11 years.

INTRODUCTION: Physical inactivity is hypothesized to be a contributing factor in the development of a variety of diseases. Recommendations for an adequate level of physical activity have been proposed. There are few studies in which the physical activity in children has been objectively assessed. The purpose of this study was to estimate objectively the level of physical activity in Swedish children. MATERIALS AND METHODS: We studied 248 children (140 boys and 108 girls) aged 7.9-11.1 years from Malmö, Sweden. Physical activity was measured with accelerometers. Children were instructed to wear the accelerometers for 4 days. The mean daily activity was expressed as the mean counts per minute of recording. The time that the child spent performing moderate or vigorous activity was calculated by using previously established cutoff points. RESULTS: The mean daily activity was higher in boys than in girls, 751+/-243 vs 618+/-154 counts/min (P<0.001). All children fulfilled the recommendation for moderate physical activity for 60 min or more per day. Ninety-two percent of the boys and 86% of the girls performed vigorous activity, for 20 min or more per day. CONCLUSION: All children, aged 8-11 years, who participated in this study reached the recommended level of physical activity, with boys being more active than girls.

Child↗

Graded associations between cardiorespiratory fitness, fatness, and blood pressure in children and adolescents.

OBJECTIVE: To measure the graded relation between cardiorespiratory fitness and sum of skinfolds, waist circumference, and blood pressure in children and adolescents participating in the European youth heart study. METHODS: The participants were 4072 children and adolescents (aged 9 and 15) from Denmark, Portugal, Estonia, and Norway. Cardiorespiratory fitness was indirectly determined using a maximal ergometer cycle test. The sum of four skinfolds, waist circumference, and blood pressure were assessed with a standardised protocol. Linear regression analysis was used to test the graded relation between cardiorespiratory fitness and the dependent variables adjusted for pubertal stage, sex, and country. RESULTS: A significant curvilinear graded relation was found between cardiorespiratory fitness and waist circumference and sum of skinfolds (partial r2 for cardiorespiratory fitness was 0.09-0.26 for the different sexes and age groups). Systolic and diastolic blood pressure also showed a curvilinear relation with cardiorespiratory fitness, and fitness explained 2% of the variance in systolic blood pressure. The difference in systolic blood pressure between the least and most fit was 6 mm Hg. CONCLUSION: A curvilinear graded relation was found between cardiorespiratory fitness and waist circumference, sum of skinfolds, and systolic blood pressure. The greatest difference in these health variables was observed between low and moderate fitness levels.

Adolescent↗

Relationship between physical activity and obesity in children and adolescents.

AIM: The purpose of the present study was to analyze the relationship between physical activity (PA) and obesity in Portuguese children and adolescents. METHODS: The sample consisted of 1341 children and adolescents (8-15 years of age), 634 males (age, 10.6+/-2.3 y; body mass, 40.6+/-12.7 kg; height, 1.431+/-1.41 m) and 707 females (age, 10.9+/-2.4 y; body mass, 50+/-12.4 kg; height, 1.428+/-1.32 m). The sample was divided into quartiles of percentage of body fat (%BF) and physical activity index (PAI), within age and gender. Children in the upper %BF quartile were defined as obese (arbitrary definition). Logistic regression for each PAI quartile was used to determine the odds ratio of obese children and adolescents (> or = P75 of %BF) in comparison to their non-obese counterparts (< P75 of %BF). RESULTS: Males in the lowest PAI quartile have an odds ratio of 2.1 of having obesity in relation to males in the highest PAI quartile. For females any significant result was found between PAI quartiles. CONCLUSIONS: The results obtained in this study add some data to the controversy of PA and obesity relationship youth. Logistical regression shows that males who have a lower PAI have an odds ratio of 2.1 of obesity, in comparison with males that have higher PAI. Those findings were not found in girls.

Adolescent↗

Mini review: physical activity and fitness and its relations to cardiovascular disease risk factors in children.

OBJECTIVES: This paper aim to review the newest literature linking physical inactivity and low fitness to metabolic disorders including cardiovascular disease (CVD) risk factors and obesity. METHODS: There is a rationale for early prevention of CVD if (a) children have a risk factor profile, where risk for future disease is increased, (b) physical activity and CVD risk factors track into adulthood, and (c) increased physical activity can improve the risk factor profile. We reviewed the evidence for a progressive evolution of atherosclerosis starting in childhood, and also that physical activity decreases the rate of the process through several mechanisms. Among the central mechanisms mediating the effect of physical activity are (a) increased insulin sensitivity, (b) a non-insulin-dependent glucose uptake, which causes lower insulin release, (c) an improved ratio between HDL and LDL cholesterol because of increased activity of lipoprotein lipase, and d) improved function of other metabolic hormones and enzymes for fat metabolism. RESULTS: The association between CVD risk factors and physical activity/fitness is weak, when risk factors are analysed isolated. In the normal healthy population of children, studies have shown that risk factors cluster and this clustering is strongly related to low physical activity or fitness. In European children it has been found that as many as 15% of 9-y-old children has clustered risk. Most of the overweight and obese children are among these, but many of the children are lean inactive children, who may later become overweight because of insulin resistance. CONCLUSION: It can be concluded that there is a large potential for primary prevention of CVD in European children, and lifestyle changes including increased physical activity as one of the key actions should be initiated.

Adolescent↗

Infant feeding and components of the metabolic syndrome: findings from the European Youth Heart Study.

AIMS: To assess the associations of type and duration of infant feeding with components of the metabolic syndrome in children aged 9 and 15. METHODS: A total of 2192 randomly selected schoolchildren aged 9 and 15 years from Estonia (n = 1174) and Denmark (n = 1018) were studied. Insulin resistance (homoeostasis model assessment), triglyceride levels, high density lipoprotein cholesterol, and systolic blood pressure were measured. RESULTS: Children who had ever been exclusively breast fed had lower systolic blood pressures than those who were not. With full adjustment for age, sex, country, birth weight, pubertal stage, body mass index, height, maternal and paternal education, income, smoking, and body mass index the mean systolic blood pressure of children who had ever been breast fed was 1.7 mm Hg (95% CI -3.0 to -0.5) lower than those who had never been exclusively breast fed. There was a dose-response in this association with decreasing mean systolic blood pressure across categories from never exclusively breast fed to breast fed for more than six months. Exclusive breast feeding was not associated with other components of the metabolic syndrome. Results were similar when examined separately in each country. CONCLUSIONS: The magnitude of the association, its independence of important confounding factors, and the dose-response suggest that exclusive breast feeding is causally associated with reduced systolic blood pressure. The magnitude of the effect we found with blood pressure is comparable to the published effects of salt restriction and physical activity on blood pressure in adult populations, suggesting that it is of public health importance.

Adolescent↗

Maximum oxygen uptake and objectively measured physical activity in Danish children 6-7 years of age: the Copenhagen school child intervention study.

OBJECTIVES: To provide normative data on maximum oxygen uptake (Vo(2)max) and physical activity in children 6-7 years of age and analyse the association between these variables. METHODS: Vo(2)max was measured in 366 boys (mean (SD) 6.8 (0.4) years of age) and 332 girls (6.7 (0.4) years of age) from preschool classes in two suburban communities in Copenhagen, during a progressive treadmill exercise. Habitual physical activity was measured with accelerometers. RESULTS: Boys had higher Vo(2)max both in absolute values (1.19 (0.18) v 1.06 (0.16) litres/min (+11%), p<0.001) and relative to body weight (48.5 (6.0) v 44.8 (5.6) ml/kg/min (+8%); p<0.001) than girls. The difference in Vo(2)max between boys and girls decreased to +2% when expressed relative to lean body mass (LBM). Absolute Vo(2)max was related to LBM, body mass, and stature (all p<0.001). Boys were more physically active than girls (mean counts +9.4%, p<0.001), and even when boys and girls with the same Vo(2)max were compared, boys were more active. The difference in physical activity between the sexes was higher when sustained activity of higher intensity was compared. CONCLUSIONS: Vo(2)max is higher in boys than girls (+11%), even when related to body mass (+8%) and LBM (+2%). Most of the difference in Vo(2)max relative to body mass was explained by the larger percentage body fat in girls. When boys and girls with the same Vo(2)max were compared, boys engaged in more minutes of exercise of at least moderate intensity.

Body Composition↗

Objectively measured physical activity correlates with indices of insulin resistance in Danish children. The European Youth Heart Study (EYHS).

OBJECTIVE: To explore the association between measures of insulin resistance with objectively assessed physical activity. DESIGN: School-based, cross-sectional study. SUBJECTS: A randomly selected sample of 589 children (310 girls, 279 boys, mean (standard deviations, s.d.) age=9.7 (0.44) y, weight=33.6 (6.4) kg, height=1.39 (0.06) m) from Denmark. METHODS: Fasting blood samples were analysed for serum insulin and glucose. Physical activity was measured with the uniaxial Computer Science and Applications (CSA) model 7164 accelerometer, worn for at least 3 days (>/=10 h day(-1)). Adiposity was assessed by the sum of four skinfolds. Multiple linear regression were performed to model insulin and glucose from average CSA output, adjusted for age, gender, puberty, ethnicity, birth weight, parental smoking, socioeconomic group, and CSA unit. In addition, we adjusted for skinfold thickness. RESULTS: Mean fasting serum glucose ranged from 4.1 to 6.5 mmol l(-1) with a mean (s.d.) of 5.1 (0.37) mmol l(-1). Fasting insulin was negatively correlated with CSA output on levels of adjustment. Fasting glucose was not significantly associated with physical activity. However, in girls both indices of insulin resistance were significantly related to activity, whereas in boys none of the associations were significant. CONCLUSION: Physical activity is inversely associated with fasting insulin in the nondiabetic range of fasting glucose. The relationship was stronger for insulin than for glucose, indicating compensatory action by the beta cells. Our data emphasise the importance of physical activity in children for the maintenance of metabolic control.

Biomarkers↗

Secular trends in physical fitness and obesity in Danish 9-year-old girls and boys: Odense School Child Study and Danish substudy of the European Youth Heart Study.

INTRODUCTION: Low physical fitness and obesity have been shown to be associated with cardiovascular disease (CVD) risk. Obesity is on the increase in many countries, but little is known about physical fitness trends. Monitoring of changes in fitness and obesity in the population is important for preventive strategies, and the aim of this study was to analyse the secular trends in fitness and body composition in Danish children. MATERIALS AND METHODS: Two representative population studies were conducted 12 years apart on 9-year-old children in the same location: the Odense School Child Study in 1985-86 and the European Youth Heart Study in 1997-98. In both studies, physical fitness was determined by a maximal cycle ergometer test, and obesity was assessed by skinfolds. RESULTS: Boys had a lower physical fitness and were fatter in 1997-98 than in 1985-86. In addition, an increased polarization is emerging, with the difference between the fit and the unfit and the difference between the lean and the fat being greater in 1997-98 than in 1985-86. In girls, a similar polarization was found, but no overall change in fitness or obesity. CONCLUSION: The negative trend and increased polarization for physical fitness and obesity in Danish children suggest a future generation with a higher degree of CVD risk.

Cardiovascular Diseases↗

Biological cardiovascular risk factors cluster in Danish children and adolescents: the European Youth Heart Study.

BACKGROUND: The aim of this study was to determine whether the number of participants with multiple coronary heart disease (CHD) risk factors exceeded the number expected from a random distribution. METHODS: A cross-sectional study of 1020 randomly selected boys and girls, 9 and 15 years old, was conducted. Risk factors were total cholesterol, HDL-cholesterol, triglyceride, serum insulin, and blood pressure. Physical fitness was assessed from a maximal cycle test and body fat from the sum of four skinfolds. Risk factors selected in the analysis were those related to the metabolic syndrome. RESULTS: More participants than expected had four or five CHD risk factors. Four risk factors were found in 3.03 (95% confidence interval (CI): 2.24-4.10) times as many participants as expected from a random distribution and five risk factors were found in 8.70 (95% CI: 4.35-17.4) times as many participants as expected. Fifty (5.4%) had four or five risk factors and in these individuals physical fitness was 1.2 standard deviation (SD) lower and body mass index (BMI) 1.6 SD higher than mean values for the population. CONCLUSION: Clustering of risk factors for the metabolic syndrome was found in children and adolescents. Low levels of physical fitness and raised BMI in these individuals indicate that lifestyle factors such as physical activity and diet may influence the development of these unhealthy risk profiles.

Adolescent↗

Secular trends in acute myocardial infarction in relation to physical activity in the general Danish population.

Secular trends in AMI rates were analyzed in relation to physical activity levels. The population attributable risk of physical inactivity was calculated. Participants were randomly selected subjects from a suburb of Copenhagen, Denmark, screened during the years 1964-1991. Occupational physical activity and in leisure time were assessed 1964, 1974, 1976, 1982, 1987 and 1991 by self-administered questionnaire along with smoking habits and alcohol consumption. Blood pressure, weight, height and serum lipids were measured according to WHO-standards. Mortality data were obtained from death certificates, from hospital records or autopsies. Acute myocardial infarctions (AMI) 1964-1994 were included. 13.925 men and women aged 30, 40, 50 and 60 years, were drawn as random samples from a background population of 300.000 inhabitants. A cohort born in 1914 was examined in 1964 and 1974, a cohort born in 1936, was examined in 1976 and 1987; Monica (Monitoring trends and determinants in cardiovascular diseases) I cohort were examined in 1982 and 1987; MONICA II in 1986, and MONICA III in 1991. Mean physical activity level at leisure adjusted for age and sex increased over time (P < 0001). 25% of the men were sedentary, and more women reported a sedentary lifestyle than men. The overall trend was from 1964 to 1992 a decline in physical activity at work (P < 0001) in both gender and all age groups. The difference in AMI incidence rates between leisure time physical activity (LTPA) levels increased over time. No change was found in AMI rates comparing sedentary in different time periods. A remarkable decrease over time in the AMI incidence rate was found in physically active during leisure time. Population attributable risk (PAR) exceeded 40% in both genders in the late 1980s. In conclusion the difference in AMI rates between LTPA subgroups has increased over time. The low AMI rates observed among the most physically active reveal a substantial potential for the prevention of AMI through physical activity. A population attributable risk of more than 40% for physical inactivity suggests a potential for primary prevention through increased physical activity.

Adult↗

Physical fitness and physical activity during adolescence as predictors of cardiovascular disease risk in young adulthood. Danish Youth and Sports Study. An eight-year follow-up study.

The purpose of this study was to determine if physical activity, aerobic fitness and isometric strength during adolescence were predictors of cardiovascular risk factor levels in young adulthood. The following measurements were carried out: maximal oxygen uptake (VO(2)max), maximal voluntary contraction (MVC) in four muscle groups, physical activity (questionnaire), blood pressure (BP), total cholesterol, high density lipoprotein cholesterol (HDL-C), triglycerides, anthropometric variables and body fat % (sum of four skinfolds). The data were collected from the Danish Youth and Sports study, an observational longitudinal study in which two measurements were carried out over an eight-year period. The findings in this study indicated that the relationships between the absolute levels of physical fitness and activity in adolescence and the subsequent level of CVD risk factors are weak. However, the changes in physical fitness and physical activity were related to the absolute levels of CVD risk factors in young adulthood, especially in men. Weak relationships were found between the changes in physical fitness/activity and changes in CVD risk factor levels in both sexes. In conclusion, many subjects changed their levels of physical activity and physical fitness between adolescence and young adulthood and the changes, especially in aerobic fitness, seemed to be the best predictor of CVD risk factor levels in young adulthood.

Adolescent↗

Back pain reporting pattern in a Danish population-based sample of children and adolescents.

STUDY DESIGN: A cross-sectional survey of 806 pupils in Odense, Denmark was performed. This survey included children and adolescents ages 8 to 10 and 14 to 16 years obtained through two-stage cluster sampling from schools stratified according to school type, location, and socioeconomic character of the uptake area. OBJECTIVES: To establish the 1-month prevalence of neck, middle back, and low back pain and the consequences this disorder may have in relation to age and gender. SUMMARY OF BACKGROUND DATA: The differences in definitions of back pain and the variety of age groups included in previous studies make it difficult to draw clear conclusions about the onset of pain for various spinal regions in the young. METHODS: Information on back pain within the preceding month, obtained through a standardized interview of 481 children and 325 adolescents, was categorized according to area of pain, age, and gender. The consequences of back pain also were studied. RESULTS: The 1-month prevalence of back pain was 39%. Thoracic pain is most common in childhood, whereas thoracic pain and lumbar pain are equally common in adolescence. Neck pain and pain in more than one area of the spine are rare in both age groups. No gender differences were found. Of those who had back pain, 38% also reported some type of consequence, usually either visits to a medical physician or diminished physical activities. CONCLUSIONS: For clinical and research purposes, neck pain, middle back pain, and low back pain in childhood should be regarded as three specific entities. In future research the data for different age groups should be reported separately.

Adolescent↗

[Obesity among children--with particular reference to Danish circumstances].

Obesity is one of the most important predictors and causes of such lifestyle diseases as metabolic syndrome, type 2 diabetes, and cardiovascular disease. It is thus imperative to follow the trend longitudinally in the population. Measurement of obesity in children and adolescents is difficult; many studies use the body mass index as a measure, regardless of the fact that it is inappropriate. Skinfolds or the ponderal index should be used, instead. Recent Danish studies suggest that the incidence of childhood and adolescent obesity is increasing and that those who are overweight are even more so today than earlier. Obesity is caused by a number of factors, genetic, social, environmental, and lifestyle, all of which play an important role. One of the main causes of the increase in childhood obesity in Denmark today is the lower level of physical activity than formerly. The prospects for the future are an increase in obesity and incidence of lifestyle diseases with a poorer quality of life and a shorter life time expectancy.

Adolescent↗