Tuomo Tompuri

Physical activity and sedentary behaviour in relation to cardiometabolic risk in children: cross-sectional findings from the Physical Activity and Nutrition in Children (PANIC) Study

BackgroundLower levels of physical activity (PA) and sedentary behaviour (SB) have been associated with increased cardiometabolic risk among children. However, little is known about the independent and combined associations of PA and SB as well as different types of these behaviours with cardiometabolic risk in children. We therefore investigated these relationships among children.MethodsThe subjects were a population sample of 468 children 6–8 years of age. PA and SB were assessed by a questionnaire administered by parents and validated by a monitor combining heart rate and accelerometry measurements. We assessed body fat percentage, waist circumference, blood glucose, serum insulin, plasma lipids and lipoproteins and blood pressure and calculated a cardiometabolic risk score using population-specific Z-scores and a formula waist circumference + insulin + glucose + triglycerides - HDL cholesterol + mean of systolic and diastolic blood pressure. We analysed data using multivariate linear regression models.ResultsTotal PA was inversely associated with the cardiometabolic risk score (β = -0.135, p = 0.004), body fat percentage (β = -0.155, p < 0.001), insulin (β = -0.099, p = 0.034), triglycerides (β = -0.166, p < 0.001), VLDL triglycerides (β = -0.230, p < 0.001), VLDL cholesterol (β = -0.168, p = 0.001), LDL cholesterol (β = -0.094, p = 0.046) and HDL triglycerides (β = -0.149, p = 0.004) and directly related to HDL cholesterol (β = 0.144, p = 0.002) adjusted for age and gender. Unstructured PA was inversely associated with the cardiometabolic risk score (β = -0.123, p = 0.010), body fat percentage (β = -0.099, p = 0.027), insulin (β = -0.108, p = 0.021), triglycerides (β = -0.144, p = 0.002), VLDL triglycerides (β = -0.233, p < 0.001) and VLDL cholesterol (β = -0.199, p < 0.001) and directly related to HDL cholesterol (β = 0.126, p = 0.008). Watching TV and videos was directly related to the cardiometabolic risk score (β = 0.135, p = 0.003), body fat percentage (β = 0.090, p = 0.039), waist circumference (β = 0.097, p = 0.033) and systolic blood pressure (β = 0.096, p = 0.039). Resting was directly associated with the cardiometabolic risk score (β = 0.092, p = 0.049), triglycerides (β = 0.131, p = 0.005), VLDL triglycerides (β = 0.134, p = 0.009), VLDL cholesterol (β = 0.147, p = 0.004) and LDL cholesterol (β = 0.105, p = 0.023). Other types of PA and SB had less consistent associations with cardiometabolic risk factors.ConclusionsThe results of our study emphasise increasing total and unstructured PA and decreasing watching TV and videos and other sedentary behaviours to reduce cardiometabolic risk among children.Trial registrationClinicalTrials.gov Identifier: NCT01803776.

Associations of Motor and Cardiovascular Performance with Academic Skills in Children

PURPOSE We investigated the associations of cardiovascular and motor performance in grade 1 with academic skills in grades 1-3. METHODS The participants were 6- to 8-yr-old children with complete data in grades 1-2 for 174 children and in grade 3 for 167 children. Maximal workload during exercise test was used as a measure of cardiovascular performance. The shuttle run test (SRT) time, the errors in balance test, and the number of cubes moved in box and block test (BBT) were measures of motor performance. Academic skills were assessed using reading fluency, reading comprehension, and arithmetic skill tests. RESULTS Among boys, longer SRT time was associated with poorer reading fluency in grades 1-3 (β = -0.29 to -0.39, P < 0.01), reading comprehension in grades 1-2 (β = -0.25 to -0.29, P < 0.05), and arithmetic skills in grades 1-3 (β = -0.33 to -0.40, P < 0.003). Poorer balance was related to poorer reading comprehension (β = -0.20, P = 0.042). The smaller number of cubes moved in BBT was related to poorer reading fluency in grades 1-2 (β = 0.23-0.28, P < 0.03), reading comprehension in grade 3 (β = 0.23, P = 0.037), and arithmetic skills in grades 1-2 (β = 0.21-0.23, P < 0.043). Among girls, longer SRT time was related to poorer reading fluency in grade 3 (β = -0.27, P = 0.027) and arithmetic skills in grade 2 (β = -0.25, P = 0.040). The smaller number of cubes moved in BBT was associated with worse reading fluency in grade 2 (β = 0.26, P = 0.030). Cardiovascular performance was not related to academic skills. CONCLUSIONS Poorer motor performance was associated with worse academic skills in children, especially among boys. These findings emphasize early identification of children with poor motor performance and actions to improve these childrens motor performance and academic skills during the first school years.

Assessment of body composition by dual-energy X-ray absorptiometry, bioimpedance analysis and anthropometrics in children: the Physical Activity and Nutrition in Children study.

We compared InBody720 segmental multifrequency bioimpedance analysis (SMF‐BIA) with Lunar Prodigy Advance dual‐energy X‐ray absorptiometry (DXA) in assessment of body composition among 178 predominantly prepubertal children. Segmental agreement analysis of body compartments was carried out, and inter‐relationships of anthropometric and other measures of body composition were defined. Moreover, the relations of different reference criteria for excess body fat were evaluated.

Associations of physical activity and sedentary behavior with academic skills--a follow-up study among primary school children.

Background There are no prospective studies that would have compared the relationships of different types of physical activity (PA) and sedentary behavior (SB) with academic skills among children. We therefore investigated the associations of different types of PA and SB with reading and arithmetic skills in a follow-up study among children. Methods The participants were 186 children (107 boys, 79 girls, 6–8 yr) who were followed-up in Grades 1–3. PA and SB were assessed using a questionnaire in Grade 1. Reading fluency, reading comprehension and arithmetic skills were assessed using standardized tests at the end of Grades 1–3. Results Among all children more recess PA and more time spent in SB related to academic skills were associated with a better reading fluency across Grades 1–3. In boys, higher levels of total PA, physically active school transportation and more time spent in SB related to academic skills were associated with a better reading fluency across the Grades 1–3. Among girls, higher levels of total PA were related to worse arithmetic skills across Grades 1–3. Moreover, total PA was directly associated with reading fluency and arithmetic skills in Grades 1–3 among girls whose parents had a university degree, whereas these relationships were inverse in girls of less educated parents. Conclusions Total PA, physically active school transportation and SB related to academic skills may be beneficial for the development of reading skills in boys, whereas factors that are independent of PA or SB may be more important for academic skills in girls. Trial Registration ClinicalTrials.gov: NCT01803776

Normal values for heart rate variability parameters in children 6–8 years of age: the PANIC Study

Measurement of heart rate variability (HRV) is a useful method for examining cardiac autonomic control. HRV has been measured in many studies among adults, but research on this topic among children is limited. We therefore defined reference values for a large number of HRV parameters among children.

Cardiovascular fitness and haemodynamic responses to maximal cycle ergometer exercise test in children 6–8 years of age

Abstract We investigated cardiovascular fitness and haemodynamic responses to maximal cycle ergometer exercise test in children. The participants were a population sample of 425 children (204 girls, 221 boys) aged 6–8 years. Heart rate (HR) and systolic blood pressure (SBP) were measured from the beginning of pre-exercise rest to the end of recovery period. We provided reference values for peak workload and changes in HR and SBP during and after maximal exercise test in girls and boys. Girls had a lower cardiovascular fitness, indicated by peak workload per body weight [mean (2 s) 2.7 (0.9) vs. 3.1 (1.0) W · kg–1, P < 0.001] and lean mass [mean (2 s) 3.5 (0.9) vs. 3.8 (1.0) W· kg–1, P < 0.001] than boys. Plateau or decline in SBP close to the end of the test was found in about third of children and was considered a normal SBP response. Girls had a slower HR decrease within 2 min after the test than boys [mean (2 s) 53 (18) vs. 59 (22) beats · min–1, P < 0.001]. The results are useful for physicians and exercise physiologists to evaluate cardiovascular fitness and haemodynamic responses to exercise in children and to detect children with low exercise tolerance or abnormal haemodynamic responses to exercise.

Measures of cardiorespiratory fitness in relation to measures of body size and composition among children

In the exercise testing measures of cardiorespiratory fitness need to be scaled by body size or composition to enable comparison between individuals. Traditionally used weight‐proportional measures are potentially confounded by body adiposity that hampers their interpretation and applicability in the clinical assessment of cardiorespiratory fitness.

The Presentation of Adrenarche Is Sexually Dimorphic and Modified by Body Adiposity

CONTEXT Adrenarche refers to the onset of increased production of adrenal androgens in childhood leading variably to clinical signs of androgen action. The prevalence and presentation of adrenarche in prepubertal girls and boys is not well known. OBJECTIVE Our objective was to examine the prevalence and clinical presentation of adrenarche in a population sample of prepubertal children aged less than 9 years. DESIGN AND PARTICIPANTS This cross-sectional study included prepubertal children (209 girls and 228 boys; median age 7.6 [range 6.8-8.9] years) taking part in The Physical Activity and Nutrition in Children (PANIC) Study. MAIN OUTCOME MEASURE The prevalence of adrenarche was assessed. RESULTS The prevalence of any clinical sign of androgen action was higher in girls than in boys (26.1% vs 10.0%; P < .001) and biochemical adrenarche without any clinical sign was less common in girls than in boys (8.1% vs 16.7%; P = .007). When premature adrenarche was defined by serum dehydroepiandrosterone sulfate concentration ≥1 μmol/L (≥37 μg/dL) and any clinical sign before the age of 8 years in girls and 9 years in boys, its total prevalence was 8.6% in girls and 1.8% in boys. The risk of having any clinical sign increased with higher body fat percentage in boys and with higher serum dehydroepiandrosterone sulfate concentration in girls. CONCLUSIONS Clinical signs of androgen action are more common, but biochemical adrenarche without any clinical sign is less common in prepubertal girls than boys. This sexual dimorphism of adrenarche might be explained by sex-dependent differences in peripheral androgen metabolism or action that are modified by body fat.

Associations of cardiorespiratory fitness, physical activity, and adiposity with arterial stiffness in children

Associations of cardiorespiratory fitness (CRF), physical activity (PA), sedentary behavior, and body fat percentage (BF%) with arterial stiffness and dilation capacity were investigated in 160 prepubertal children (83 girls) 6–8 years of age. We assessed CRF (watts/lean mass) by maximal cycle ergometer exercise test, total PA, structured exercise, unstructured PA, commuting to and from school, recess PA and total and screen‐based sedentary behavior by questionnaire, BF% using dual‐energy X‐ray absorptiometry, and arterial stiffness and dilation capacity using pulse contour analysis. Data were adjusted for sex and age. Poorer CRF (standardized regression coefficient β = −0.297, P < 0.001), lower unstructured PA (β = −0.162, P = 0.042), and higher BF% (β = 0.176, P = 0.044) were related to higher arterial stiffness. When CRF, unstructured PA, and BF% were in the same model, only CRF was associated with arterial stiffness (β = −0.246, P = 0.006). Poorer CRF was also related to lower arterial dilation capacity (β = 0.316, P < 0.001). Children with low CRF (< median) and high BF% (≥ median; P = 0.002), low CRF and low unstructured PA (< median; P = 0.006) or children with low unstructured PA and high BF% (P = 0.005) had higher arterial stiffness than children in the opposite halves of these variables. Poor CRF was independently associated with increased arterial stiffness and impaired arterial dilation capacity among children.

Reproducibility of pulse contour analysis in children before and after maximal exercise stress test: The Physical Activity and Nutrition in Children (PANIC) Study

Objective:  Arterial stiffness index (SI) and reflection index (RI) from digital pulse contour analysis have been shown to be good measures of arterial stiffness and may be useful in the evaluation of endothelial function. Finger skin temperature (FST) is also considered to reflect peripheral circulatory functions. We evaluated the reproducibility of SI, RI and FST before and after the exercise stress test.