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Screen Time and Sedentary Lifestyles: Unmasking the Risks to Heart Health

by Hania Siddiqui

Graphic design by Emily Huang

We live in a digital age where nearly everyone has access to electronic devices, and this exposure begins at increasingly younger ages. A Canadian study found that almost all children in Canada are exposed to screens by the age of two, and only 15% of children aged three to four meet the recommended screen time guidelines of less than one hour per day.1

It’s no surprise that electronics consume much of our daily lives, impacting both children and adults. However, excessive electronic use comes with significant risks. One major concern is that increased screen time displaces physical activity, leading to more sedentary behaviour. Sedentary behaviour is defined as any activity involving ≤1.5 metabolic equivalents of task (METs) of energy expenditure while in a seated, reclined, or lying posture .2 It’s important to distinguish sedentary behaviour from physical inactivity. A person can still be considered active by meeting the recommended 150 to 300 minutes of moderate-intensity physical activity per week, as outlined by the World Health Organization (WHO), yet still engage in sedentary behaviour due to work or leisure activities that involve prolonged sitting .3

A recent study published in The Lancet examined physical activity reports from adults across 163 countries and found that nearly one-third (31%) of the world’s population does not engage in sufficient physical activity .4

Advanced technology has undoubtedly made daily tasks more convenient, with apps and online services for nearly everything. However, the increased reliance on motorized transport and screen time for both recreational, education, and work purposes has contributed to more sedentary lifestyles .3 The COVID-19 pandemic exacerbated this issue and was associated with greater physical inactivity .5,6 Confinement to the indoors and feeling unsafe outdoors potentially served as a barrier for many people to get active during the pandemic.

The dangers of prolonged screen time and sedentary behaviours are numerous. Excessive screen time is well-known to contribute to mental health issues such as anxiety and stress, as well as physical health problems like obesity, type 2 diabetes, and even cancer .7,8 But did you know that sedentary behaviours, such as scrolling through your phone or sitting in front of a laptop for hours, can also negatively impact your heart health? In fact, the negative effects of inactivity on cardiovascular function can manifest within a short period, with studies showing that 3-6 hours of uninterrupted sitting can cause deterioration in vascular function .9 

Common cardiovascular diseases, including coronary artery disease, heart failure, and ischemic heart disease, are closely linked to metabolic activity .10 A study using Mendelian randomization—a technique that uses genetic variants to establish causal relationships between exposure factors and outcomes—found a significant causal association between screen time (specifically mobile phone and TV use) and cardiovascular diseases .10 Interestingly, computer use was not significantly associated with cardiovascular disease.

A survey of 2,000 remote and hybrid workers in the United States conducted by the Upright Pose team revealed some alarming findings .11 Fifty-four percent of these workers estimated that they had reduced their mobility during work hours by 50% or more in the past year, with 63% reporting that they only walked to the bathroom or kitchen during a typical remote workday. While the flexibility of working from home is convenient and life-changing for many, prolonged inactivity can be problematic if one does not make an effort to exercise. Sitting for long periods, as many remote workers do, can increase the risk of developing blood clots, which can travel through the veins, block blood flow to the heart, and potentially cause a heart attack .12

Fortunately, physical inactivity and sedentary behaviour are modifiable risk factors, meaning that measures can be taken to reduce the chances of developing cardiovascular disease and other conditions .13 Taking proactive steps to ensure adequate daily physical activity can make a significant difference in your overall health and well-being. Your heart will thank you for it!

References

  1. Lavie, C. J., Ozemek, C., Carbone, et al. Sedentary behavior, exercise, and Cardiovascular Health. Circulation Research, 2019; 124(5), 799–815. https://doi.org/10.1161/circresaha.118.312669
  2. Ponti, M.  Screen Time and preschool children: Promoting health and development in a Digital World. Paediatrics & Child Health. 2023; 28(3):–192. https://doi.org/10.1093/pch/pxac125
  3. What is sedentary behaviour?. The Sedentary Behaviour Research Network (SBRN) [Internet]. 2017 June  https://www.sedentarybehaviour.org/what-is-sedentary-behaviour/#:~:text=Sedentary%20behavior%20is%20any%20waking,are%20engaging%20in%20sedentary%20behaviour  
  4. World Health Organization. Physical activity. World Health Organization [Internet]. https://www.who.int/news-room/fact-sheets/detail/physical-activity
  5. Strain, T., Flaxman, S., Guthold, R., et al. National, regional, and global trends in insufficient physical activity among adults from 2000 to 2022: A pooled analysis of 507 population-based surveys with 5·7 million participants. The Lancet Global Health. 2024 Aug; 12(8): e1232-e1243. https://doi.org/10.1016/s2214-109x(24)00150-5
  6. Peçanha T, Goessler K. F, Roschel, H, et al. Social isolation during the COVID-19 pandemic can increase physical inactivity and the global burden of cardiovascular disease. American Journal of Physiology-Heart and Circulatory Physiology. 2020; 318(6); . https://doi.org/10.1152/ajpheart.00268.2020
  7. Kinoshita, K., Ozato, N., Yamaguchi, T. et al. Association of the COVID-19 pandemic with changes in objectively measured sedentary behaviour and adiposity.  International Journal of Obesity. 2023 Feb 16; 47, 375–381.. https://doi.org/10.1038/s41366-023-01274-9
  8. Nakshine VS, Thute P, Khatib MN, et al. Increased Screen Time as a Cause of Declining Physical, Psychological Health, and Sleep Patterns: A Literary Review. Cureus. 2022 Oct 8;14(10):e30051. doi: 10.7759/cureus.30051.
  9. Hunter RF, Murray JM, Coleman HG. The association between recreational screen time and cancer risk: findings from the UK Biobank, a large prospective cohort study. Int J Behav Nutr Phys Act. 2020 Aug 03;17(1):97. doi: 10.1186/s12966-020-00997-6.
  10. Thosar SS, Bielko SL, Mather KJ, et al. Effect of prolonged sitting and breaks in sitting time on endothelial function. Med Sci Sports Exerc 47: 843–849, 2015. doi: 10.1249/MSS.0000000000000479.Qiu, Z., Jia, X., Fu, Y., et al. Screen Time in the development of cardiovascular diseases: A two-sample mendelian randomization study. Nutrition, Metabolism and Cardiovascular Diseases, 2024 Oct 03; 34(3), 706–717. https://doi.org/10.1016/j.numecd.2023.09.029
  11. Qiu, Z., Jia, X., Fu, Y. Screen Time in the development of cardiovascular diseases: A two-sample mendelian randomization study. Nutrition, Metabolism and Cardiovascular Diseases, 2024 Oct 03; 34(3), 706–717. https://doi.org/10.1016/j.numecd.2023.09.029
  12. The health dilemma of the work from Home Era. UPRIGHT Posture Training Device [Internet]. (2021, May 28). https://www.uprightpose.com/the-health-dilemma-of-the-work-from-home-era/
  13. O’Connell-Domenech, A. Remote work poses risks to physical health. The Hill [Internet]. (2023a, July 4). https://thehill.com/changing-america/well-being/4076569-remote-work-poses-risks-to-physical-health/