ORCID Profile
0000-0002-3384-7940
Current Organisation
University of Zurich
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Springer Science and Business Media LLC
Date: 31-10-2019
DOI: 10.1186/S12966-019-0858-6
Abstract: Evidence on the association between sitting for extended periods (i.e. prolonged sedentary time (PST)) and cardio-metabolic health is inconsistent in children. We aimed to estimate the differences in cardio-metabolic health associated with substituting PST with non-prolonged sedentary time (non-PST), light (LIPA) or moderate-to-vigorous physical activity (MVPA) in children. Cross-sectional data from 14 studies (7 countries) in the International Children’s Accelerometry Database (ICAD, 1998–2009) was included. Accelerometry in 19,502 participants aged 3–18 years, together with covariate and outcome data, was pooled and harmonized. Iso-temporal substitution in linear regression models provided beta coefficients (95%CI) for substitution of 1 h/day PST (sedentary time accumulated in bouts 15 min) with non-PST, LIPA or MVPA, for each study, which were meta-analysed. Modelling substitution of 1 h/day of PST with non-PST suggested reductions in standardized BMI, but estimates were 7-fold greater for substitution with MVPA (− 0.44 (− 0.62 − 0.26) SD units). Only reallocation by MVPA was beneficial for waist circumference (− 3.07 (− 4.47 − 1.68) cm), systolic blood pressure (− 1.53 (− 2.42 − 0.65) mmHg) and clustered cardio-metabolic risk (− 0.18 (− 0.3 − 0.1) SD units). For HDL-cholesterol and diastolic blood pressure, substitution with LIPA was beneficial however, substitution with MVPA showed 5-fold stronger effect estimates (HDL-cholesterol: 0.05 (0.01 0.10) mmol/l) diastolic blood pressure: − 0.81 (− 1.38 − 0.24) mmHg). Replacement of PST with MVPA may be the preferred scenario for behaviour change, given beneficial associations with a wide range of cardio-metabolic risk factors (including adiposity, HDL-cholesterol, blood pressure and clustered cardio-metabolic risk). Effect estimates are clinically relevant (e.g. an estimated reduction in waist circumference of ≈1.5 cm for 30 min/day replacement). Replacement with LIPA could be beneficial for some of these risk factors, however with substantially lower effect estimates.
Publisher: Elsevier BV
Date: 05-2015
Publisher: Cold Spring Harbor Laboratory
Date: 13-06-2022
DOI: 10.1101/2022.06.09.22275139
Abstract: (1) To develop reference values for health-related fitness European children and adolescents aged 6–18 years that are the foundation for the web-based, open-access and multi-language fitness platform (FitBack) (2) To provide comparisons across European countries. This study builds on a previous large fitness reference study in European youth by: (1) widening the age demographic, (2) identifying the most recent and representative country-level data, and (3) including national data from existing fitness surveillance and monitoring systems. We used the ALPHA test battery as it comprises tests with the highest test-retest reliability, criterion/construct validity, and health-related predictive validity: the 20-m shuttle run (cardiorespiratory fitness) handgrip strength and standing long jump (muscular strength) and body height, body mass, body mass index, and waist circumference (anthropometry). Percentile values were obtained using the GAMLSS method. A total of 7,966,693 data points from 34 countries (106 datasets) were used to develop sex- and age-specific percentile values. In addition, country-level rankings based on mean percentiles are provided for each fitness test, as well as an overall fitness ranking. Finally, an interactive fitness platform, including in idual and group reporting, and European fitness maps, is provided and freely available at www.fitbackeurope.eu . This study discusses the major implications of fitness assessment in youth from a health, educational and sport perspective, and how the FitBack reference values and interactive web-based platform contribute to it. Fitness testing can be conducted in school and/or sport settings, and the interpreted results be integrated in the healthcare systems across Europe. - Fitness testing in youth is important from a health, educational and sport point of view. - The EU-funded ALPHA project reviewed the existing evidence and proposed a selection of field-based fitness tests that showed the highest test-retest reliability, criterion/construct validity, and health-related predictive validity among available tests. - The FitBack project provides the most up-to-date and geographically erse reference fitness values for 6-to 18-year-old Europeans. - This study introduces the first web-based, open-access, and multi-lingual fitness reporting platform (FitBack) providing interactive information and visual mapping of the European fitness landscape. - From a health perspective, very low fitness levels are a non-invasive indicator of poor health at both the in idual and group level (e.g., school, region), which have utility for health screening and may guide public health policy. There are already ex les of regional and national fitness testing systems that are integrated into the healthcare systems. - From an educational perspective, fitness testing is part of the school curriculum in many countries, and the FitBack platform offers physical education teachers an easy-to-use tool for interpreting fitness test results by sex and age. - From a sport perspective, these reference values can help identify young in iduals who are talented in specific fitness components.
Publisher: Springer Science and Business Media LLC
Date: 12-2017
Publisher: Oxford University Press (OUP)
Date: 19-03-2018
DOI: 10.1093/IJE/DYY016
Publisher: BMJ
Date: 09-01-2023
DOI: 10.1136/BJSPORTS-2022-106176
Abstract: (1) To develop reference values for health-related fitness in European children and adolescents aged 6–18 years that are the foundation for the web-based, open-access and multilanguage fitness platform (FitBack) (2) to provide comparisons across European countries. This study builds on a previous large fitness reference study in European youth by (1) widening the age demographic, (2) identifying the most recent and representative country-level data and (3) including national data from existing fitness surveillance and monitoring systems. We used the Assessing Levels of PHysical Activity and fitness at population level (ALPHA) test battery as it comprises tests with the highest test–retest reliability, criterion/construct validity and health-related predictive validity: the 20 m shuttle run (cardiorespiratory fitness) handgrip strength and standing long jump (muscular strength) and body height, body mass, body mass index and waist circumference (anthropometry). Percentile values were obtained using the generalised additive models for location, scale and shape method. A total of 7 966 693 test results from 34 countries (106 datasets) were used to develop sex-specific and age-specific percentile values. In addition, country-level rankings based on mean percentiles are provided for each fitness test, as well as an overall fitness ranking. Finally, an interactive fitness platform, including in idual and group reporting and European fitness maps, is provided and freely available online ( www.fitbackeurope.eu ). This study discusses the major implications of fitness assessment in youth from health, educational and sport perspectives, and how the FitBack reference values and interactive web-based platform contribute to it. Fitness testing can be conducted in school and/or sport settings, and the interpreted results be integrated in the healthcare systems across Europe.
Publisher: Springer Science and Business Media LLC
Date: 13-07-2018
Publisher: BMJ
Date: 26-07-2011
DOI: 10.1136/BJSPORTS-2011-090333
Abstract: A number of recent systematic reviews have resulted in changes in international recommendations for children's participation in physical activity (PA) for health. The World Health Authority (WHO) has recently released new recommendations. The WHO still recommends 60 min of moderate to vigorous physical activity (MVPA), but also emphasises that these minutes should be on top of everyday physical activities. Everyday physical activities total around 30 min of MVPA in the quintile of the least active children, which means that the new recommendations constitute more activity in total compared with earlier recommendations. To summarise evidence justifying new PA recommendation for cardiovascular health in children. The results of recent systematic reviews are discussed and supplemented with relevant literature not included in these reviews. PubMed was searched for the years 2006-2011 for additional topics not sufficiently covered by the reviews. PA was associated with lower blood pressure and a healthier lipid blood profile in children. The association was stronger when a composite risk factor score was analysed, and the associations between physical fitness and cardiovascular disease (CVD) risk factors were even stronger. Muscle strength and endurance exercise each had an effect on blood lipids and insulin sensitivity even if the effect was smaller for muscle strength than for aerobic exercise. New evidence suggests possible effects of PA on C-reactive protein. There is accumulating evidence that PA can have beneficial effects on the risk factors of CVD in children. Public health policy to promote PA in children, especially the most sedentary children, may be a key element to prevent the onset of CVD later in the children's lives.
Publisher: Elsevier BV
Date: 12-2016
Publisher: BMJ
Date: 17-06-2015
DOI: 10.1136/BJSPORTS-2015-094962
Abstract: The health, fitness and other advantages of youth sports participation are well recognised. However, there are considerable challenges for all stakeholders involved-especially youth athletes-in trying to maintain inclusive, sustainable and enjoyable participation and success for all levels of in idual athletic achievement. In an effort to advance a more unified, evidence-informed approach to youth athlete development, the IOC critically evaluated the current state of science and practice of youth athlete development and presented recommendations for developing healthy, resilient and capable youth athletes, while providing opportunities for all levels of sport participation and success. The IOC further challenges all youth and other sport governing bodies to embrace and implement these recommended guiding principles.
Publisher: BMJ
Date: 11-08-2011
Publisher: Springer Science and Business Media LLC
Date: 03-06-2020
DOI: 10.1038/S41586-020-2338-1
Abstract: High blood cholesterol is typically considered a feature of wealthy western countries 1,2 . However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world 3 and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health 4,5 . However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million in iduals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol—which is a marker of cardiovascular risk—changed from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million–4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.
Publisher: Springer Science and Business Media LLC
Date: 29-03-2023
DOI: 10.1038/S41586-023-05772-8
Abstract: Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being 1–6 . Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was .1 kg m –2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have lified.
Publisher: Elsevier BV
Date: 11-2020
Publisher: Springer Science and Business Media LLC
Date: 05-2019
Publisher: Springer Science and Business Media LLC
Date: 10-02-2021
DOI: 10.1186/S12966-021-01095-X
Abstract: The Structured Days Hypothesis (SDH) posits that children’s behaviors associated with obesity – such as physical activity – are more favorable on days that contain more ‘structure’ (i.e., a pre-planned, segmented, and adult-supervised environment) such as school weekdays, compared to days with less structure, such as weekend days. The purpose of this study was to compare children’s moderate-to-vigorous physical activity (MVPA) levels on weekdays versus weekend days using a large, multi-country, accelerometer-measured physical activity dataset. Data were received from the International Children’s Accelerometer Database (ICAD) July 2019. The ICAD inclusion criteria for a valid day of wear, only non-intervention data (e.g., baseline intervention data), children with at least 1 weekday and 1 weekend day, and ICAD studies with data collected exclusively during school months, were included for analyses. Mixed effects models accounting for the nested nature of the data (i.e., days within children) assessed MVPA minutes per day (min/day MVPA) differences between weekdays and weekend days by region/country, adjusted for age, sex, and total wear time. Separate meta-analytical models explored differences by age and country/region for sex and child weight-status. Valid data from 15 studies representing 5794 children (61% female, 10.7 ± 2.1 yrs., 24% with overweight/obesity) and 35,263 days of valid accelerometer data from 5 distinct countries/regions were used. Boys and girls accumulated 12.6 min/day (95% CI: 9.0, 16.2) and 9.4 min/day (95% CI: 7.2, 11.6) more MVPA on weekdays versus weekend days, respectively. Children from mainland Europe had the largest differences (17.1 min/day more MVPA on weekdays versus weekend days, 95% CI: 15.3, 19.0) compared to the other countries/regions. Children who were classified as overweight/obese or normal weight/underweight accumulated 9.5 min/day (95% CI: 6.9, 12.2) and 10.9 min/day (95% CI: 8.3, 13.5) of additional MVPA on weekdays versus weekend days, respectively. Children from multiple countries/regions accumulated significantly more MVPA on weekdays versus weekend days during school months. This finding aligns with the SDH and warrants future intervention studies to prioritize less-structured days, such as weekend days, and to consider providing opportunities for all children to access additional opportunities to be active.
Publisher: Elsevier BV
Date: 03-2016
Publisher: American Thoracic Society
Date: 02-2018
Publisher: Springer Science and Business Media LLC
Date: 18-03-2020
DOI: 10.1186/S12966-020-00930-X
Abstract: Levels of physical activity and variation in physical activity and sedentary time by place and person in European children and adolescents are largely unknown. The objective of the study was to assess the variations in objectively measured physical activity and sedentary time in children and adolescents across Europe. Six databases were systematically searched to identify pan-European and national data sets on physical activity and sedentary time assessed by the same accelerometer in children (2 to 9.9 years) and adolescents (≥10 to 18 years). We harmonized in idual-level data by reprocessing hip-worn raw accelerometer data files from 30 different studies conducted between 1997 and 2014, representing 47,497 in iduals (2–18 years) from 18 different European countries. Overall, a maximum of 29% (95% CI: 25, 33) of children and 29% (95% CI: 25, 32) of adolescents were categorized as sufficiently physically active. We observed substantial country- and region-specific differences in physical activity and sedentary time, with lower physical activity levels and prevalence estimates in Southern European countries. Boys were more active and less sedentary in all age-categories. The onset of age-related lowering or leveling-off of physical activity and increase in sedentary time seems to become apparent at around 6 to 7 years of age. Two third of European children and adolescents are not sufficiently active. Our findings suggest substantial gender-, country- and region-specific differences in physical activity. These results should encourage policymakers, governments, and local and national stakeholders to take action to facilitate an increase in the physical activity levels of young people across Europe.
Publisher: Wiley
Date: 10-10-2014
DOI: 10.1111/ALL.12525
Abstract: Both obesity and asthma are highly prevalent, complex diseases modified by multiple factors. Genetic, developmental, lung mechanical, immunological and behavioural factors have all been suggested as playing a causal role between the two entities however, their complex mechanistic interactions are still poorly understood and evidence of causality in children remains scant. Equally lacking is evidence of effective treatment strategies, despite the fact that imbalances at vulnerable phases in childhood can impact long-term health. This review is targeted at both clinicians frequently faced with the dilemma of how to investigate and treat the obese asthmatic child and researchers interested in the topic. Highlighting the breadth of the spectrum of factors involved, this review collates evidence regarding the investigation and treatment of asthma in obese children, particularly in comparison with current approaches in 'difficult-to-treat' childhood asthma. Finally, the authors propose hypotheses for future research from a systems-based perspective.
Publisher: BMJ
Date: 13-01-2021
DOI: 10.1136/BJSPORTS-2020-102740
Abstract: To determine if subpopulations of students benefit equally from school-based physical activity interventions in terms of cardiorespiratory fitness and physical activity. To examine if physical activity intensity mediates improvements in cardiorespiratory fitness. Pooled analysis of in idual participant data from controlled trials that assessed the impact of school-based physical activity interventions on cardiorespiratory fitness and device-measured physical activity. Data for 6621 children and adolescents aged 4–18 years from 20 trials were included. Peak oxygen consumption (VO 2Peak mL/kg/min) and minutes of moderate and vigorous physical activity. Interventions modestly improved students’ cardiorespiratory fitness by 0.47 mL/kg/min (95% CI 0.33 to 0.61), but the effects were not distributed equally across subpopulations. Girls and older students benefited less than boys and younger students, respectively. Students with lower levels of initial fitness, and those with higher levels of baseline physical activity benefitted more than those who were initially fitter and less active, respectively. Interventions had a modest positive effect on physical activity with approximately one additional minute per day of both moderate and vigorous physical activity. Changes in vigorous, but not moderate intensity, physical activity explained a small amount (~5%) of the intervention effect on cardiorespiratory fitness. Future interventions should include targeted strategies to address the needs of girls and older students. Interventions may also be improved by promoting more vigorous intensity physical activity. Interventions could mitigate declining youth cardiorespiratory fitness, increase physical activity and promote cardiovascular health if they can be delivered equitably and their effects sustained at the population level.
Publisher: American Thoracic Society
Date: 15-04-2019
Publisher: Springer Science and Business Media LLC
Date: 18-05-2020
DOI: 10.1186/S12966-020-00960-5
Abstract: To gain more understanding of the potential health effects of sedentary time, knowledge is required about the accumulation and longitudinal development of young people’s sedentary time. This study examined tracking of young peoples’ total and prolonged sedentary time as well as their day-to-day variation using the International Children’s Accelerometry Database. Longitudinal accelerometer data of 5991 children (aged 4-17y) was used from eight studies in five countries. Children were included if they provided valid (≥8 h/day) accelerometer data on ≥4 days, including ≥1 weekend day, at both baseline and follow-up (average follow-up: 2.7y range 0.7–8.2). Tracking of total and prolonged (i.e. ≥10-min bouts) sedentary time was examined using multilevel modelling to adjust for clustering of observations, with baseline levels of sedentary time as predictor and follow-up levels as outcome. Standardized regression coefficients were interpreted as tracking coefficients (low: 0.3 moderate: 0.3–0.6 high: 0.6). Average total sedentary time at study level ranged from 246 to 387 min/day at baseline and increased annually by 21.4 min/day (95% confidence interval [19.6–23.0]) on average. This increase consisted almost entirely of prolonged sedentary time (20.9 min/day [19.2–22.7]). Total (standardized regression coefficient (B) = 0.48 [0.45–0.50]) and prolonged sedentary time (B = 0.43 [0.41–0.45]) tracked moderately. Tracking of day-to-day variation in total (B = 0.04 [0.02–0.07]) and prolonged (B = 0.07 [0.04–0.09]) sedentary time was low. Young people with high levels of sedentary time are likely to remain among the people with highest sedentary time as they grow older. Day-to-day variation in total and prolonged sedentary time, however, was rather variable over time.
Publisher: BMJ
Date: 07-2023
DOI: 10.1136/BMJSEM-2023-001626
Abstract: Non-communicable diseases (NCDs), including coronary heart disease, stroke, hypertension, type 2 diabetes, dementia, depression and cancers, are on the rise worldwide and are often associated with a lack of physical activity (PA). Globally, the levels of PA among in iduals are below WHO recommendations. A lack of PA can increase morbidity and mortality, worsen the quality of life and increase the economic burden on in iduals and society. In response to this trend, numerous organisations came together under one umbrella in Hamburg, Germany, in April 2021 and signed the ‘Hamburg Declaration’. This represented an international commitment to take all necessary actions to increase PA and improve the health of in iduals to entire communities. In iduals and organisations are working together as the ‘Global Alliance for the Promotion of Physical Activity’ to drive long-term in idual and population-wide behaviour change by collaborating with all stakeholders in the community: active hospitals, physical activity specialists, community services and healthcare providers, all achieving sustainable health goals for their patients/clients. The ‘Hamburg Declaration’ calls on national and international policymakers to take concrete action to promote daily PA and exercise at a population level and in healthcare settings.
No related grants have been discovered for Susi Kriemler.