Physiology of physical inactivity, sedentary behaviours and non‐exercise activity: insights from the space bedrest model
- 21 February 2021
- journal article
- review article
- Published by Wiley in Journal Of Physiology-London
- Vol. 600 (5), 1037-1051
- https://doi.org/10.1113/jp281064
Abstract
Physical inactivity, i.e. not reaching the recommended level of physical activity (PA), and sedentary behaviours (SB), i.e. sitting time, have been associated with increased risk for common metabolic diseases. Recent epidemiological data suggest that high volumes of SB are detrimental to metabolic health, even in the presence of regular exercise, i.e. moderate/vigorous PA. This suggests that the health effects of SB are independent from those of exercise. However, experimentally testing this hypothesis is complicated because of the difficulty in disassociating SB from PA. Bedrest studies, a traditional space science model, can offer new insights. In some bedrest studies, an exercise training protocol has been used to counteract the harmful effects of inactivity. While bedrest induces an inactive and sedentary state, exercise with bedrest represents a unique model of sedentary yet physically active people. Here, we review bedrest studies with and without exercise training. Although exercise training prevents the loss of muscle mass and function, even large volumes of exercise are not sufficient to fully counteract the negative metabolic adaptations triggered by inactivity. This observation supports the existence of independent adverse health effects of SB, but also the potential benefits of non-exercise activity, i.e. daily living light PA. We gathered available data to examine the complex relationships between exercise, non-exercise activity, SB and health outcomes. Given the large amount of SB in modern societies, the sole promotion of exercise, i.e. moderate/vigorous PA may be insufficient, and promotion of light PA may be a complimentary approach to improve health.Keywords
Funding Information
- National Institute of Diabetes and Digestive and Kidney Diseases
This publication has 63 references indexed in Scilit:
- Daily Sitting Time and All-Cause Mortality: A Meta-AnalysisPLOS ONE, 2013
- In silico Platform for Prediction of N-, O- and C-Glycosites in Eukaryotic Protein SequencesPLOS ONE, 2013
- Effects of different levels of physical inactivity on plasma visfatin in healthy normal-weight menApplied Physiology, Nutrition, and Metabolism, 2013
- Minimal Intensity Physical Activity (Standing and Walking) of Longer Duration Improves Insulin Action and Plasma Lipids More than Shorter Periods of Moderate to Vigorous Exercise (Cycling) in Sedentary Subjects When Energy Expenditure Is ComparablePLOS ONE, 2013
- Effect of physical inactivity on major non-communicable diseases worldwide: an analysis of burden of disease and life expectancyThe Lancet, 2012
- GLUT4 and Glycogen Synthase Are Key Players in Bed Rest–Induced Insulin ResistanceDiabetes, 2012
- Impact of 9 Days of Bed Rest on Hepatic and Peripheral Insulin Action, Insulin Secretion, and Whole-Body Lipolysis in Healthy Young Male Offspring of Patients With Type 2 DiabetesDiabetes, 2009
- Physical Inactivity Differentially Alters Dietary Oleate and Palmitate TraffickingDiabetes, 2009
- Molecular biomarkers monitoring human skeletal muscle fibres and microvasculature following long‐term bed rest with and without countermeasuresJournal of Anatomy, 2008
- Effect of Physical Inactivity on the Oxidation of Saturated and Monounsaturated Dietary Fatty Acids: Results of a Randomized TrialPLoS Clinical Trials, 2006