Reproducibility and relative validity of a semiquantitative food frequency questionnaire in European preschoolers: The ToyBox study

Objectives: The aim of this study was to examine the reproducibility and relative validity of a semiquantitative food frequency questionnaire (FFQ) in assessing food group estimates. Methods: Food group estimates were assessed via a 37-item FFQ and a 3-d food record (FR). Pearson's correlation coefficients for log-transformed values were calculated to assess the reproducibility and Spearman's rank correlation coefficients for log-transformed values were calculated to assess the validity. Kindergartens from six European countries participated in the preparatory substudies of the ToyBox intervention study; data from preschool children 4 to 6 y of age (n = 196, reproducibility study; n = 324, validation study) were obtained. Results: In the reproducibility study, positive Pearson's correlation coefficients for single and aggregated food groups ranged from 0.14 for pasta and rice to 0.90 for cooked vegetables. In the validation study, the FR gave higher estimates of 40 of the 50 food items (single and aggregated) examined compared with those obtained from the FFQ. Positive crude Spearman rank correlation coefficients ranged from 0.01 for total beverages (added sugar) and rice to 0.62 for tea. Corrections for the deattenuation effect did not improve observed correlations. Quartiles and tertiles were calculated for a small number of food groups (N = 14) owing to zero consumption in the rest of the groups. Conclusions: Moderately good reproducibility and low-moderate relative validity of the FFQ used in preschool children was observed. Relative validity, however, varied by food and beverage group; for some of the “key” foods/drinks targeted in the ToyBox intervention (e.g., biscuits), the validity was good. The findings should be considered in future epidemiologic and intervention studies in preschool children

Do physical activity and screen time mediate the association between European fathers' and their children's weight status? Cross-sectional data from the Feel4Diabetes-study

BACKGROUND: Most research on parenting and childhood obesity and obesity-related behaviours has focused on mothers while fathers have been underrepresented. Yet, recent literature has suggested that fathers uniquely influence their children''s lifestyle behaviours, and hence could also affect their weight status, but this has not yet been scientifically proven. Therefore, the present study aimed to determine whether the association between fathers'' weight status and their children''s weight status is mediated by fathers'' and children''s movement behaviours (i.e. physical activity (PA) and screen time (ST)). METHODS: Cross-sectional data of 899 European fathers and their children were analyzed. Fathers/male caregivers (mean age =¿43.79¿±¿5.92¿years, mean BMI =¿27.08¿±¿3.95) completed a questionnaire assessing their own and their children''s (mean age =¿8.19¿±¿0.99¿years, 50.90% boys, mean BMIzscore =¿0.44¿±¿1.07) movement behaviours. Body Mass Index (BMI, in kg/m2) was calculated based on self-reported (fathers) and objectively measured (children) height and weight. For children, BMI z-scores (SD scores) were calculated to obtain an optimal measure for their weight status. Serial mediation analyses were performed using IBM SPSS 25.0 Statistics for Windows to test whether the association between fathers'' BMI and children''s BMI is mediated by fathers'' PA and children''s PA (model 1) and fathers'' ST and children''s ST (model 2), respectively. RESULTS: The present study showed a (partial) mediation effect of fathers'' PA and children''s PA (but not father''s ST and children''s ST) on the association between fathers'' BMI and children''s BMI (model for PA; coefficient: 0.001, 95% CI: [0.0001, 0.002]; model for ST; coefficient: 0.001, 95% CI: [0.000, 0.002]). Furthermore, fathers'' movement behaviours (PA and ST) were positively associated with their children''s movement behaviours (PA and ST) (model for PA, coefficient: 0.281, SE: 0.023, p <¿0.001; model for ST, coefficient: 0.345, SE: 0.025, p¿<¿0.001). CONCLUSIONS: These findings indicate that the influence of fathers on their children''s weight status partially occurs through the association between fathers'' PA and children''s PA (but not their ST). As such, intervening by focusing on PA of fathers but preferably of both members of the father-child dyad (e.g. engaging fathers and their children in co-PA) might be a novel and potentially effective strategy for interventions aiming to prevent childhood overweight and obesity. Longitudinal studies or intervention studies confirming these findings are however warranted to make meaningful recommendations for health intervention and policy. TRIAL REGISTRATION: The Feel4Diabetes-study is registered with the clinical trials registry http://clinicaltrials.gov , ID: 643708

Differences in energy balance-related behaviours in European preschool children: The ToyBox-study

Background: The aim of the current study was to compare levels of energy balance-related behaviours (physical activity, sedentary behaviour, and dietary behaviours (more specifically water consumption, sugar-sweetened beverage consumption and unhealthy snacking)) in four- to six-year-old preschoolers from six European countries (Belgium, Bulgaria, Germany, Greece, Poland, and Spain) within the ToyBox cross-sectional study. Methods: A sample of 4,045 preschoolers (4.77 ± 0.43 years; 52.2% boys) had valid physical activity data (steps per day), parents of 8,117 preschoolers (4.78 ± 0.46 years; 53.0% boys) completed a parental questionnaire with questions on sedentary behaviours (television viewing, computer use, and quiet play), and parents of 7,244 preschoolers (4.77 ± 0.44 years; 52.0% boys) completed a food frequency questionnaire with questions on water consumption, sugar-sweetened beverage consumption and unhealthy snacking. Results: The highest levels of physical activity were found in Spain (12,669 steps/day on weekdays), while the lowest levels were found in Bulgaria and Greece (9,777 and 9,656 steps/day on weekdays, respectively). German preschoolers spent the least amount of time in television viewing (43.3 min/day on weekdays), while Greek preschoolers spent the most time in television viewing (88.5 min/day on weekdays). A considerable amount of time was spent in quiet play in all countries, with the highest levels in Poland (104.9 min/day on weekdays), and the lowest levels in Spain (60.4 min/day on weekdays). Belgian, German, and Polish preschoolers had the lowest intakes of water and the highest intakes of sugar-sweetened beverages. The intake of snacks was the highest in Belgian preschoolers (73.1 g/day) and the lowest in Greek preschoolers (53.3 g/day). Conclusions: Across six European countries, differences in preschoolers'' energy balance-related behaviours were found. Future interventions should target European preschoolers '' energy balance- related behaviours simultaneously, but should apply country-specific adaptations

Effect and process evaluation of a kindergarten-based, family-involved cluster randomised controlled trial in six European countries on four- to six-year-old children's steps per day: The ToyBox-study

Background: The ToyBox-intervention is a theory- and evidence-based intervention delivered in kindergartens to improve four- to six-year-old children''s energy balance-related behaviours and prevent obesity. The current study aimed to (1) examine the effect of the ToyBox-intervention on increasing European four- to six-year-old children'' steps per day, and (2) examine if a higher process evaluation score from teachers and parents was related to a more favourable effect on steps per day. Methods: A sample of 2438 four- to six-year-old children (51.9% boys, mean age 4.75±0.43years) from 6 European countries (Belgium, Bulgaria, Germany, Greece, Poland and Spain) wore a motion sensor (pedometer or accelerometer) for a minimum of two weekdays and one weekend day both at baseline and follow-up to objectively measure their steps per day. Kindergarten teachers implemented the physical activity component of the ToyBox-intervention for 6 weeks in total, with a focus on (1) environmental changes in the classroom, (2) the child performing the actual behaviour and (3) classroom activities. Children''s parents received newsletters, tip cards and posters. To assess intervention effects, multilevel repeated measures analyses were conducted for the total sample and the six intervention countries separately. In addition, process evaluation questionnaires were used to calculate a total process evaluation score (with implementation and satisfaction as a part of the overall score) for teachers and parents which was then linked with the physical activity outcomes. Results: No significant intervention effects on four- to six-year-old children'' steps per weekday, steps per weekend day and steps per average day were found, both in the total sample and in the country-specific samples (all p>0.05). In general, the intervention effects on steps per day were least favourable in four- to six-year-old children with a low teachers process evaluation score and most favourable in four- to six-year-old children with a high teachers process evaluation score. No differences in intervention effects were found for a low, medium or high parents'' process evaluation score. Conclusion: The physical activity component of the ToyBox-intervention had no overall effect on four- to six-year-old children'' steps per day. However, the process evaluation scores showed that kindergarten teachers that implemented the physical activity component of the ToyBox-intervention as planned and were satisfied with the physical activity component led to favourable effects on children''s steps per day. Strategies to motivate, actively involve and engage the kindergarten teachers and parents/caregivers are needed to induce larger effects

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI 2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining https://researchonline.ljmu.ac.uk/images/research_banner_face_lab_290.jpgunderweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity

The innervation and organization of motor units in a series-fibered human muscle: the brachioradialis

We studied the innervation and organization of motor units in the brachioradialis muscle of 25 normal human subjects. We recorded intramuscular EMG signals at points separated by 15 mm along the proximodistal muscle axis during moderate isometric contractions, identified from 27 to 61 (mean 39) individual motor units per subject using EMG decomposition, and estimated the locations of the endplates and distal muscle/tendon junctions from the motor-unit action potential (MUAP) propagation patterns and terminal standing waves. In three subjects all the motor units were innervated in a single endplate zone. In the other 22 subjects, the motor units were innervated in 3–6 (mean 4) distinct endplate zones separated by 15–55 mm along the proximodistal axis. One-third of the motor units had fibers innervated in more than one zone. The more distally innervated motor units had distinct terminal waves indicating tendonous termination, while the more proximal motor units lacked terminal waves, indicating intrafascicular termination. Analysis of blocked MUAP components revealed that 19% of the motor units had at least one doubly innervated fiber, i.e., a fiber innervated in two different endplate zones by two different motoneurons, and thus belonging to two different motor units. These results are consistent with the brachioradialis muscle having a series-fibered architecture consisting of multiple, overlapping bands of muscle fibers in most individuals and a simple parallel-fibered architecture in some individuals

Breastfeeding and overweight in european preschoolers: The toybox study

The benefits of breastfeeding (BF) include risk reduction of later overweight and obesity. We aimed to analyse the association between breastfeeding practices and overweight/obesity among preschool children participating in the ToyBox study. Data from children in the six countries, participating in the ToyBox-study (Belgium, Bulgaria, Germany, Greece, Poland, and Spain) 7554 children/families and their age is 3.5–5.5 years, 51.9% were boys collected cross-sectionally in 2012. The questionnaires included parents’ self-reported data on their weight, height, socio-demographic status, and infant feeding practices. Measurements of preschool children’s weight and height were done by trained researchers using standard protocols and equipment. The ever breastfeeding rate in the total sample was 85.0% (n = 5777). Only 6.3% (n = 428) of the children from the general sample were exclusively breastfed (EBF) for the duration of the first six months. EBF for four to six months was significantly (p 0.05). It is likely that sociodemographic and lifestyle factors associated with breastfeeding practices may have an impact on childhood obesity. The identified lower than desirable rates and duration of breastfeeding practices should prompt enhanced efforts for effective promotion, protection, and support of breastfeeding across Europe, and in particular in regions with low BF rates. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Electrophysiological evidence of adult human skeletal muscle fibres with multiple endplates and polyneuronal innervation

Electromyographic (EMG) signals were recorded using intramuscular electrodes at six different sites in the brachioradialis muscles during voluntary isometric contractions in four subjects. The potential waveforms and discharge patterns of up to 12 simultaneously active motor units were identified from each signal using computer-aided decomposition. Out of a total of 301 motor unit potentials identified, 23 potentials exhibited behaviour consistent with having been generated by muscle fibres that were innervated by two different motoneurons at widely separated endplates. These potentials discharged in association with two different motor units, but were blocked or delayed whenever the two motor units discharged within a few milliseconds of one another. The blocking was consistent with a collision or refractoriness when one motoneuron tried to excite the fibre while it was already conducting an action potential initiated by the other motoneuron. The delays were consistent with decreased conduction velocity associated with incomplete recovery of the fibre after a preceding action potential. From the temporal separation between the discharges of the two motoneurons that resulted in blocking, the spatial separation between the endplates was estimated to be between 26 and 44 mm. These findings challenge the classical concept of the motor unit as an anatomically distinct and functionally independent entity. It is suggested that the human brachioradialis muscle may contain both long, polyneuronally innervated fibres and short, serially linked, singly innervated fibres