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Fletta eftir höfundi "Brychta, Robert J."

Fletta eftir höfundi "Brychta, Robert J."

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    Comparison of summer and winter objectively measured physical activity and sedentary behavior in older adults: Age, gene/environment susceptibility Reykjavik study 
    Arnardóttir, Nanna Ýr; Óskarsdóttir, Nína Dóra; Brychta, Robert J.; Koster, Annemarie; van Domelen, Dane R.; Caserotti, Paolo; Eiriksdottir, Gudny; Sverrisdóttir, Jóhanna E.; Jóhannsson, Erlingur; Launer, Lenore J.; Gudnason, Vilmundur; Harris, Tamara B.; Chen, Kong Y.; Sveinsson, Thorarinn (MDPI AG, 2017-10-21)
    In Iceland, there is a large variation in daylight between summer and winter. The aim of the study was to identify how this large variation influences physical activity (PA) and sedentary behavior (SB). Free living PA was measured by a waist-worn ...
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    Comparison of summer and winter objectively measured physical activity and sedentary behavior in older adults: Age, gene/environment susceptibility Reykjavik study 
    Arnardóttir, Nanna Ýr; Oskarsdottir, Nina Dora; Brychta, Robert J.; Koster, Annemarie; Van Domelen, Dane R.; Caserotti, Paolo; Eiriksdottir, Gudny; Sverrisdottir, Johanna E.; Johannsson, Erlingur; Launer, Lenore J.; Guðnason, Vilmundur G; Harris, Tamara B.; Chen, Kong Y.; Sveinsson, Þórarinn (2017-10-21)
    In Iceland, there is a large variation in daylight between summer and winter. The aim of the study was to identify how this large variation influences physical activity (PA) and sedentary behavior (SB). Free living PA was measured by a waist-worn ...
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    Dynamic sitting: Measurement and associations with metabolic health 
    van der Berg, Julianne D.; Stehouwer, Coen D.A.; Bosma, Hans; Caserotti, Paolo; Eiriksdottir, Gudny; Arnardóttir, Nanna Ýr; Van Domelen, Dane R.; Brychta, Robert J.; Chen, Kong Y.; Sveinsson, Thorarinn; Johannsson, Erlingur; Launer, Lenore J.; Gudnason, Vilmundur; Jónsson, Pálmi V.; Harris, Tamara B.; Koster, Annemarie (Informa UK Limited, 2019-03-30)
    Dynamic sitting, such as fidgeting and desk work, might be associated with health, but remains difficult toidentify out of accelerometry data. We examined, in a laboratory study, whether dynamic sitting can beidentified out of triaxial activity counts. ...
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    Influence of day length and physical activity on sleep patterns in older Icelandic men and women 
    Brychta, Robert J.; Arnardottir, Nanna Yr; Johannsson, Erlingur; Wright, Elizabeth C.; Eiriksdottir, Gudny; Gudnason, Vilmundur; Marinac, Catherine R.; Davis, Megan; Koster, Annemarie; Caserotti, Paolo; Sveinsson, Thorarinn; Harris, Tamara; Chen, Kong Y. (2016-02-15)
    Study Objectives: To identify cross-sectional and seasonal patterns of sleep and physical activity (PA) in community-dwelling, older Icelandic adults using accelerometers. Methods: A seven-day free-living protocol of 244 (110 female) adults aged 79.7 ...
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    Less screen time and more frequent vigorous physical activity is associated with lower risk of reporting negative mental health symptoms among Icelandic adolescents 
    Hrafnkelsdóttir, Soffía Margrét; Brychta, Robert J.; Rögnvaldsdóttir, Vaka; Gestsdottir, Sunna; Chen, Kong Y.; Jóhannsson, Erlingur Sigurður; Guðmundsdóttir, Sigriður Lára; Arngrímsson, Sigurbjörn Árni (Public Library of Science (PLoS), 2018-04-26)
    Objective Few studies have explored the potential interrelated associations of screen time and physical activity with mental health in youth, particularly using objective methods. We examined cross-sectional associations of these variables among ...
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    Longitudinal Change in Adolescent Bedtimes Measured by Self-Report and Actigraphy 
    Brychta, Robert J.; Rögnvaldsdóttir, Vaka; Gudmundsdottir, Sigridur Lara; Stefansdottir, Runa; Hrafnkelsdóttir, Soffía Margrét; Gestsdottir, Sunna; Arngrímsson, Sigurbjörn Árni; Chen, Kong Y.; Jóhannsson, Erlingur (Human Kinetics, 2019-12-01)
    Introduction: Sleep is often quantified using self-report or actigraphy. Self-report is practical and less technically challenging, but prone to bias. We sought to determine whether these methods have comparable sensitivity to measure longitudinal ...
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    Screen Time and Body Image in Icelandic Adolescents : Sex-Specific Cross-Sectional and Longitudinal Associations 
    Hrafnkelsdottir, Soffia M.; Brychta, Robert J.; Rognvaldsdottir, Vaka; Chen, Kong Y.; Johannsson, Erlingur; Guðmundsdottir, Sigridur L.; Arngrimsson, Sigurbjorn A. (2022-01-24)
    Studies of adolescent body image and screen use are mostly limited to girls, and longitudinal data are scarce. We examined cross-sectional and longitudinal associations between these variables in mid-adolescent boys and girls. Data was collected when ...