
Anders GrøntvedUniversity of Southern Denmark | SDU · Institute of Sports Science and Clinical Biomechanics
Anders Grøntved
MSc, MPH, PhD
About
172
Publications
45,317
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
9,479
Citations
Introduction
Additional affiliations
August 2008 - present
Publications
Publications (172)
Wearable technologies open up new avenues for the assessment of individual physical activity behaviour. Particularly, free-living heart rate (HR) data assessed by optical sensors are becoming widely available. However, while an abundancy of scientific information and guidance exists for the processing of raw acceleration data, no universal recommen...
Background
The widespread ownership of digital devices among adolescents presents challenges and opportunities in schools, particularly during recess. This study aimed to examine the association of screen use during recess with physical activity behaviours.
Methods
The study was based on a population-based cross-sectional study including 1347 adol...
Aim
To provide detailed descriptions of the amount of daily physical activity (PA) performed by people with multimorbidity and investigate the association between the number of conditions, multimorbidity profiles, and PA.
Methods
All adults (≥18 years) from The Lolland-Falster Health Study, conducted from 2016 to 2020, who had PA measured with acc...
Background
Childhood obesity can have significant negative consequences for children’s wellbeing and long-term health. Prior school-based interventions to prevent child overweight and obesity have shown limited effects, highlighting the necessity for comprehensive approaches addressing complex drivers of childhood obesity. “Generation Healthy Kids”...
Importance
Excessive screen media use has been associated with poorer mental health among children and adolescents in several observational studies. However, experimental evidence supporting this hypothesis is lacking.
Objective
To investigate the effects of a 2-week screen media reduction intervention on children’s and adolescents’ mental health....
Objectives
A new school policy mandating 45 min physical activity daily during school was introduced in Denmark in 2014. We aimed to evaluate the effect of this policy on BMI in school-aged children. It was hypothesized that the school policy would decrease BMI, especially in the obese fraction of the population (90th percentile BMI).
Study design...
OBJECTIVE: This study aimed to examine differences in heart rate variability (HRV) across accelerometer-derived position, self-reported sleep, and different summary measures (sleep, 24h-HRV) in free-living settings using open-source methodology.
APPROACH: HRV is a biomarker of autonomic activity. As it is strongly affected by factors such as physic...
Purpose:
To study the effectiveness of a preschool staff-delivered motor skills intervention on body composition and physical activity over a 2.5-year time frame.
Methods:
In this pragmatic parallel cluster randomized controlled trial (16 preschools), outcome data were collected after 6 (body composition only), 18, and 30 months of intervention....
Objective
To evaluate the feasibility of a mobile health-supported intervention in patients with cardiovascular diseases after completion of a cardiac rehabilitation programme.
Methods
The feasibility study was performed in two hospitals and one municipality in Region Zealand, Denmark. Eligible participants were ≥18 years old, participated in a su...
Background
Children are spending less leisure time with their friends in person and an increasing amount of time with digital screens. These changes may negatively affect children’s physical and mental health. The Screen-Free Time with Friends Feasibility Trial will test the feasibility, including acceptability and compliance, of an intervention de...
There are currently several methods available to generate summary measures from acceleration, while ActiGraph (AG) counts as the first method to be used at large scale. The recent disclosure of the AG counts method exposes its intrinsic properties, which has not been accessible before. The intrinsic properties are the raw acceleration processing el...
Background
Childhood obesity can have significant negative consequences for children’s wellbeing and long-term physical health. In Denmark, the prevalence of overweight and obesity increases from 13% to 18% during elementary school and reaches 53% among adults, underscoring the importance of early prevention. Prior school-based interventions have s...
Introduction
This study aimed to describe objectively measured physical activity patterns, including daily activity according to day type (weekdays and weekend days) and the four seasons, frequency, distribution, and timing of engagement in activity during the day in individuals with diabetes and prediabetes and compared with individuals with no di...
BACKGROUND: Children spend increasing amounts of time on recreational screen media, which may lead to an obesogenic environment.
OBJECTIVES: We investigated the association of trajectories of screen time across ages 3, 5 and 7 years with body composition at age 7 in the Odense Child Cohort. METHODS: Data were collected in the Municipality of Odense...
Wearable physical activity sensors are widely used in research and practice as they provide objective measures of human behavior at a low cost. An important challenge for accurate assessment of physical activity behavior in free-living is the detection non-wear. Traditionally, heuristic algorithms that rely on specific interval lengths have been em...
Introduction
Habitual physical activity behaviors of individuals with new-onset type 2 diabetes are largely unknown. We aimed to investigate accelerometer-derived physical activity behaviors in individuals with newly diagnosed type 2 diabetes. We also examined sociodemographic and health-related correlates of a high-risk physical activity profile....
Objective
This study aimed to investigate the association of parental recreational screen media practices, including time use and level of smartphone addiction, with behavioral difficulties in 7-year-old children.
Methods
The study was based on cross-sectional data from The Odense Child Cohort, a community-based birth-cohort study. A total of 1,15...
Background
A new Danish school policy with a requirement for 45 min physical activity daily during school hours was introduced in 2014. The objective of this natural experiment was to evaluate the effect of this nationwide school policy on physical activity in Danish children and adolescents.
Methods
Four historical studies completed between 2009...
Studies have linked higher digital screen use with poorer mental health. However, there is limited experimental evidence to suggest a causal relationship. In this trial, we aimed to investigate the effects of limiting recreational digital screen use on mental well-being,
mood, and biomarkers of stress in healthy young and middle-aged adults. We ran...
Introduction:
The aims of this cross-sectional study were to (1) describe habitual physical activity and adherence to WHO recommendations, and (2) investigate the association of comorbidity, obesity, stress, and health-related quality of life (HRQoL) with moderate to vigorous physical activity (MVPA) among individuals with diabetes.
Research desi...
Background
Technological advances have recently made possible the estimation of maximal oxygen consumption (VO2max) by consumer wearables. However, the validity of such estimations has not been systematically summarized using meta-analytic methods and there are no standards guiding the validation protocols.
Objective
The aim was to (1) quantitativ...
Introduction
Exposure to perfluoroalkyl substances (PFAS) has been associated with lower bone mineral density (BMD) in animal and human studies, but prospective data from children are limited.
Objectives
To determine associations between prenatal and early postnatal PFAS exposure and BMD at age 7 years.
Methods
In the Odense Child Cohort, Denmark...
Aims
Little is known about the influence of parents’ screen media habits and attitudes towards screen media on children’s screen use. We investigated associations of parental screen use, their smartphone addiction and screen media attitudes, with children’s recreational screen use.
Methods
This study was based on a population-based cross-sectional...
Wearable physical activity sensors are widely used in research and practice as they provide objective measures of human behavior at a low cost. An important challenge for accurate assessment in free-living is the detection non-wear. Traditionally, heuristic algorithms that rely on specific interval lengths have been employed to detect non-wear time...
Importance:
Children and adults spend large amounts of their leisure time using screen media, which may affect their health and behavior.
Objective:
To investigate the effect of reducing household recreational screen media use on physical activity and sleep in children and adults.
Design, setting, and participants:
This was a cluster randomize...
Introduction
To enhance health and prevent secondary consequences for patients with cardiovascular disease (CVD), maintenance of an active lifestyle following participation in cardiac rehabilitation (CR) is important. However, levels of physical activity often decrease after completion of a structured CR programme. Models that support long-term beh...
I skoleåret 2014/15 trådte en ny skolereform i kraft, hvor bevægelse fik en fremtrædende rolle med lovkravet om 45 minutters daglig bevægelse integreret i undervisningen. Det er nu snart syv år siden, reformen trådte i kraft, og resultater viser, at mange skoler endnu ikke har formået at få realiseret lovkravet. Det kan der være flere årsager til,...
Background
Consumer wearables and smartphone devices commonly offer an estimate of energy expenditure (EE) to assist in the objective monitoring of physical activity to the general population. Alongside consumers, healthcare professionals and researchers are seeking to utilise these devices for the monitoring of training and improving human health....
With the emergence of machine learning for the classification of sleep and other human behaviors from accelerometer data, the need for correctly annotated data is higher than ever. We present and evaluate a novel method for the manual annotation of in-bed periods in accelerometer data using the open-source software Audacity®, and we compare the met...
Objective
Salivary cortisol and cortisone are used as biomarkers of physiological stress. Careful sampling of saliva for profiling of awakening response and the diurnal slope can be challenging in free-living environments, and validated sampling protocols are lacking. Therefore, we investigated (1) the level of compliance to a three-day home-based...
Objectives
To investigate associations of bedtimes and sleep durations with adiposity levels in children and adolescents.
Methods
Individual data were pooled for 12 247 children (5819 with follow‐up adiposity at 2.3 ± 1.4 years post‐baseline) and 3563 adolescents from 11 international studies. Associations between questionnaire‐based sleep duratio...
Screen media use is part of most children's everyday lives, but organisations have advised that use should be limited. The aims of this study were to describe 6–11-year-old Danish children's screen device ownership and screen media use (weekdays and weekends), including the role of parental education, family structure and household screen media rul...
This study evaluated the criterion validity of a newly developed application for assessing smartphone use on iOS and Android based devices. A sample of adult Danes (n=40; 40% female; median age= 42.0 years) had the application SDU DeviceTracker installed on their mobile phone together with a commercial application that served as a reference for com...
Background
Advancements in screen media devices has transformed the way families engage with screen media. Although these modern devices offer many opportunities, e.g. communication and research online, an in-depth understanding of how these devices affect our health, is lacking. Before a definite randomized controlled trial, the SCREENS pilot stud...
In Reply We thank Dr Burtscher and colleagues for raising the concern regarding the potential influence of “the healthy worker effect” on the findings of our Original Investigation.¹ The limitation of a possible selection bias of participants able to cycle was also alluded to in the Editor’s Note² published alongside our article.
Abstract
Importance: Premature death from all causes and cardiovascular disease (CVD) causes is higher among persons with diabetes.
Objective: To investigate the association between time spent cycling and all-cause and CVD mortality among persons with diabetes, as well as to evaluate the association between change in time spent cycling and risk of...
Combining accelerometry from multiple independent activity monitors worn by the same subject have gained widespread interest with the assessment of physical activity behavior. However, a difference in the real time clock accuracy of the activity monitor introduces a substantial temporal misalignment with long duration recordings which is commonly n...
Purpose:
Evidence of shared physical activity (PA) habits within families is inconsistent. The present study aimed at examining intra-family resemblance in PA during different time segments of the week.
Method:
This cross-sectional study used data from the Danish household-based population study Lolland-Falster Health Study. We assessed time spe...
Context
Parabens are used as preservatives in consumer products but are suspected of having endocrine-disrupting properties. A recent study reported an association between in utero exposure to butyl paraben and overweight in childhood, with a stronger trend in girls.
Objective
We therefore studied the association between parabens in maternal urine...
Background
Cardiorespiratory fitness may moderate the association between obesity and all‐cause mortality (ie, the “fat‐but‐fit” hypothesis), but unaddressed sources of bias are a concern.
Methods and Results
Cardiorespiratory fitness was estimated as watts per kilogram from a submaximal bicycle test in 77 169 men and women from the UK Biobank coh...
Background
Sleep is a crucial part of our lives and insufficient sleep has been linked to several health disorders in both children and adults. However, most studies are based on single night laboratory polysomnography, actigraphy, or sleep diaries. The primary aim of this study was to evaluate compliance to and perceived feasibility of the Zmachin...
Assessing vital signs such as heart rate (HR) by
wearable devices in a lifestyle-related environment
provides widespread opportunities for public health
related research and applications. Commonly,
consumer wearable devices assessing HR are based on
photoplethysmography (PPG), where HR is determined by
absorption and reflection of emitted light by...
Consumer wearable and smartphone devices provide an accessible means to objectively measure physical activity (PA) through step counts. With the increasing proliferation of this technology, consumers, practitioners and researchers are interested in leveraging these devices as a means to track and facilitate PA behavioural change. However, while the...
Background
Evidence of intra-family resemblance in physical activity (PA) is lacking. The association between parent and child PA appears weak, the influence of age and gender on this association is uncertain, and no studies have investigated the degree of resemblance in family members’ PA behaviours such as walking, sitting/lying, and biking. Thus...
Background Sleep is a crucial part of our lives and insufficient sleep has been linked to several health disorders in both children and adults. However, most studies are based on single night laboratory polysomnography, actigraphy, or sleep diaries. The primary aim of this study was to evaluate the feasibility of a novel self-administered electroen...
Background
perfluoroalkylated substances (PFAS) are highly persistent chemicals that are able to alter the human metabolism – potentially via disruption of cell signaling pathways mediated by adipokines. Both adiponectin and leptin are influenced by and exert influence on energy storage and energy expenditure, wherefore associations between PFAS an...
Background: The objective and accurate assessment of children’s sedentary and physical behavior is important for investigating their relation to health. The purpose of this study is to validate a simple and robust method for the identification of sitting, standing, walking, running and biking performed by preschool children, children and adolescent...
Background:
Childhood represents an important life stage for establishment of physical activity (PA) habits. Parents are assumed to play an important role in influencing children's PA. Earlier reviews have mainly focused on parental modelling, encouragement, and support for PA, rather than the actual PA levels of parents. Therefore, the purpose of...
Background:
The screen-media landscape has changed drastically during the last decade with wide-scale ownership and use of new portable touchscreen-based devices plausibly causing changes in the volume of screen media use and the way children and young people entertain themselves and communicate with friends and family members. This rapid developm...
Aims: To examine prospective and cross-sectional associations between screen time and blood pressure (BP) in preschool children. Methods: The Odense Child Cohort study started in January 2010. Children who were born in the municipality of Odense underwent a clinical examination at 3 and 5 years of age and their parents were asked to complete a ques...
Background:
During the recent decade presence of digital media, especially handheld devices, in everyday life, has been increasing. Survey data suggests that children and adults spend much of their leisure on screen media, including use of social media and video services. Despite much public debate on possible harmful effects of such behavioral sh...
Background:
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.
Methods:
Six da...
Background:
Lipophilic compounds such as polychlorinated biphenyls (PCBs) are primarily stored in adipose tissue, but exercise-induced lipolysis is able to release PCBs from the adipose tissue into the circulation. The plasma concentration, distribution and metabolism of PCBs can thus vary much among individuals due to inter-human variations in li...
Background: The screen-media landscape has changed drastically during the last decade with wide-scale ownership and use of new portable touchscreen-based devices plausibly causing changes in the volume of screen media use and the way children and young people entertain themselves and communicate with friends and family members. This rapid developme...
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Aim:
We evaluated the effect that increasing physical education lessons from 1.5 to 4.5 hours per week for five years had on the body mass index (BMI) and waist circumferences of children aged 5-11 years at inclusion.
Methods:
From 2008-2013, six intervention schools in Svendborg, Denmark, delivered 4.5 hours of physical education lessons per we...
Atrial natriuretic peptide (ANP) is known for its natriuretic, diuretic, and vasodilatory properties. However, ANP also has metabolic effects stimulating lipolysis and lipid oxidation. Overweight individuals have decreased circulating ANP concentrations. It has been proposed that this potential ANP deficiency could have biological consequences in o...
Objectives
To systematically review and analyse studies of high amounts of physical activity and mortality risk in the general population.
Eligibility criteria
Inclusion criteria related to follow-up (minimum 2 years), outcome (mortality from all causes, cancer, cardiovascular disease (CVD) or coronary heart disease), exposure (eg, a category of >...
Following publication of the original article [1], the author reported that the name of the collaborator group was missing from the author group.
Purpose of Review
Bicycling as a mode of transportation can be an easy and inexpensive way of integrating health enhancing physical activity into everyday life. In the present paper, we summarize the evidence from studies on bicycling for transportation and recreation in relation to cardiovascular disease prevention. We also estimate the population...
Aims/hypothesis
The study aimed to quantitatively summarise the dose–response relationships between cardiorespiratory fitness and muscular strength on the one hand and risk of type 2 diabetes on the other and estimate the hypothetical benefits associated with population-wide changes in the distribution of fitness.
Methods
We performed a systematic...
Background:
Accelerometers are widely used to assess child physical activity (PA) levels. Using the accelerometer data, several PA metrics can be estimated. Knowledge about the relationships between these different metrics can improve our understanding of children's PA behavioral patterns. It also has significant implications for comparing PA metr...