Timed physical exercise does not influence circadian rhythms and glucose tolerance in rotating night shift workers: The EuRhythDia study

Diabetes and Vascular Disease Research, vol. 17, pp. 1479164120950616

Abstract

OBJECTIVES: Night shift workers are at cardiometabolic risk due to circadian misalignment. We investigated whether infrequent exercise before each night shift that intentionally would not improve physical performance improves glucose tolerance and 24-h blood pressure profiles and synchronizes circadian rhythms of melatonin and cortisol in rotating night shift workers. METHODS: A total of 24 rotating night shift workers (mean age, 35.7 ± 11.8 years) were randomized to exercise or no intervention. Workers in the exercise group performed 15.2 ± 4.5 exercise sessions within 2 h before each night shift. Before and after 12 weeks of exercise intervention and 12 weeks after the intervention, spiroergometry, oral glucose tolerance testing and 24-h blood pressure profiles were performed. Plasma melatonin and cortisol levels were measured in 3-hourly intervals during one 24-h period on each study day. RESULTS: Exercise did not significantly change serum glucose nor insulin levels during oral glucose tolerance testing. Timed physical exercise had no effect on physical performance, nor did it change the circadian rhythms of melatonin and cortisol or influence 24-h blood pressure profiles. CONCLUSION: Physical exercise before each night shift at a low intensity level that does not improve physical performance does not affect circadian timing, glucose tolerance or 24-h blood pressure profiles in rotating night shift workers.

Authors 10

1. Juliane Hannemann

   University Medical Center Hamburg-Eppendorf

   Affiliation as printed

   Institute of Clinical Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany

2. Karin Glismann

   University Medical Center Hamburg-Eppendorf

   Affiliation as printed

   Institute of Clinical Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany

3. Debra Jean Skene

   University of Surrey

   Affiliation as printed

   Chronobiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK

4. Benita Middleton

   University of Surrey

   Affiliation as printed

   Chronobiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK

5. Bart Staels

   Inserm · Université de Lille · Institut Pasteur de Lille · Centre Hospitalier Universitaire de Lille · Récepteurs Nucléaires, Maladies Métaboliques et Cardiovasculaires

   Affiliation as printed

   Univ. Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1011–EGID, Lille, France

6. Nikolaus Marx Aachen Department of Cardiology, University Medical Center Aachen

   Universitätsklinikum Aachen

   Affiliation as printed

   Department of Cardiology, University Medical Center Aachen, Aachen, Germany

7. Peter J. Grant

   University of Leeds

   Affiliation as printed

   Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK

8. Massimo Federici

   University of Rome Tor Vergata

   Affiliation as printed

   Center for Atherosclerosis, School of Medicine, University of Rome ‘Tor Vergata’, Rome, Italy

   Center for Atherosclerosis, School of Medicine, University of Rome 'Tor Vergata', Rome, Italy

9. Josef Niebauer

   Paracelsus Medical University

   Affiliation as printed

   University Institute for Preventive and Rehabilitative Sports Medicine, Paracelsus Medical University, Salzburg, Austria

10. Rainer H. Böger corresponding

    University Medical Center Hamburg-Eppendorf

    Affiliation as printed

    Institute of Clinical Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany