A sedentary lifestyle is a type of lifestyle with little or no physical activity. A person who lives a sedentary lifestyle may colloquially be known as a couch potato. A person living a sedentary lifestyle is often sitting or lying, while reading, socializing, watching television, playing video games, or using a mobile phone/computer for much of the day. A sedentary lifestyle can contribute to many preventable causes of death. Screen time is the amount of time a person spends watching a screen such as a television, computer monitor, or mobile device. Excessive screen time is linked to negative health consequences.
Sitting still may cause premature death. The risk is higher among those that sit still more than 5 hours per day. It is shown to be a risk factor on its own independent of hard exercise and BMI. The more still, the higher risk of chronic diseases. People that sit still more than 4 hours per day have a 40 percent higher risk than those that sit fewer than 4 hours per day. However, those that exercise at least 4 hours per week are as healthy as those that sit fewer than 4 hours per day.
A sedentary lifestyle and lack of physical activity can contribute to or be a risk factor for:
- Cardiovascular disease 
- Breast cancer
- Colon cancer
- Computer vision syndrome only for computers and tablets
- High blood pressure
- Lipid disorders
- Skin problems such as hair loss
- Mortality in adults
- Spinal disc herniation (Low back pain)
As a response to concerns over health and environmental issues, some organizations have promoted active travel, which seeks to promote walking and cycling as safe and attractive alternatives to motorized transport. Additionally, some organizations have implemented exercise classes at lunch, walking challenges among co-workers, or allowing employees to stand rather than sit at their desk during the workday. Workplace interventions such as alternative activity workstations, sit-stand desks, promotion of stair use are among measures being implemented to counter the harms of sedentary workplace environments. A Cochrane systematic review published in 2016 concluded that "at present there is very low quality evidence that sit-stand desks can reduce sitting at work at the short term. There is no evidence for other types of interventions." Also, evidence was lacking on the long term health benefits of such interventions. Organizations may also offer cholesterol or blood pressure screenings to employees.
The term couch potato was coined by a friend of underground comics artist Robert Armstrong in the 1970s; Armstrong featured a group of couch potatoes in a series of comics featuring sedentary characters and with Jack Mingo and Allan Dodge created a satirical organization that purported to watch television as a form of meditation. With two books and endless promotion through the 1980s, the Couch Potatoes appeared in hundreds of newspapers, magazines and broadcasts, spreading its "turn on, tune in, veg out" message, garnering 7,000 members, and popularizing the term.
The condition, which predates the term, is characterized by sitting or remaining inactive for most of the day with little or no exercise.
Lack of exercise causes muscle atrophy, i.e. shrinking and weakening of the muscles and accordingly increases susceptibility to physical injury. Additionally, physical fitness is correlated with immune system function; a reduction in physical fitness is generally accompanied by a weakening of the immune system. A review in Nature Reviews Cardiology suggests that since illness or injury are associated with prolonged periods of enforced rest, such sedentariness has physiologically become linked to life-preserving metabolic and stress related responses such as inflammation that aid recovery during illness and injury but which due to being nonadaptive during health now lead to chronic diseases.
In the 2008 United States American National Health Interview Survey (NHIS) 36% of adults were considered inactive. 59% of adult respondents never participated in vigorous physical activity lasting more than 10 minutes per week.
- 9 to 5
- Active travel
- Childhood inactivity and obesity in the United States
- Exercise trends
- Neurobiological effects of physical exercise
- Simple living
- Sloth (deadly sin)
- Lack of physical education
- Amy E. Mark, M.Sc. and Ian Janssen, Ph.D. (2008-03-28). "Relationship between screen time and metabolic syndrome in adolescents". Jpubhealth.oxfordjournals.org. doi:10.1093/pubmed/fdn022.
- "Elsevier". Ambulatorypediatrics.org. Retrieved 2013-11-30.
- "Elsevier". Jpeds.com. Retrieved 2013-11-30.
- Olds, T.; Ridley, K.; Dollman, J. (2006). "Screenieboppers and extreme screenies: The place of screen time in the time budgets of 10–13 year-old Australian children". Australian and New Zealand Journal of Public Health. 30 (2): 137–142. doi:10.1111/j.1467-842X.2006.tb00106.x. PMID 16681334.
- Lopez AD, Mathers CD, Ezzati M, Jamison DT, Murray CJ (May 2006). "Global and regional burden of disease and risk factors, 2001: systematic analysis of population health data". Lancet. 367 (9524): 1747–57. doi:10.1016/S0140-6736(06)68770-9. PMID 16731270.
- smh.com.au - Sitting can lead to an early death: study, 2012-03-28
- Dunstan David W.; Owen Neville (2012). "New Exercise Prescription: Don't Just Sit There: Stand Up and Move More, More Often". Arch Intern Med. 172 (6): 500–501. doi:10.1001/archinternmed.2012.209.
- "Physical Activity". World Health Organization. Retrieved January 23, 2010.
- "Depression and anxiety: Exercise eases symptoms". Mayo Clinic. Retrieved January 22, 2010.
- Daniel M. Landers. "The Influence of Exercise on Mental Health". President's Council on Physical Fitness and Sports. Retrieved February 5, 2010.
The research literature suggests that for many variables there is now ample evidence that a definite relationship exists between exercise and improved mental health. This is particularly evident in the case of a reduction of anxiety and depression.
- "Risk Factors for Cardiovascular Diseases" (PDF). United States Department of Veterans Affairs. Retrieved January 22, 2010.
- "Physical inactivity a leading cause of disease and disability, warns WHO". World Health Organization. Retrieved January 23, 2010.
- "Who Is At Risk for High Blood Pressure?". National Institutes of Health. Retrieved April 15, 2010.
- Biswas, A; Oh, PI; Faulkner, GE; Bajaj, RR; Silver, MA; Mitchell, MS; Alter, DA (20 January 2015). "Sedentary time and its association with risk for disease incidence, mortality, and hospitalization in adults: a systematic review and meta-analysis.". Annals of Internal Medicine. 162 (2): 123–32. doi:10.7326/M14-1651. PMID 25599350.
- Stewart RA, Benatar J, Maddison R (2015). "Living longer by sitting less and moving more". Current Opinion in Cardiology (Review). 30 (5): 551–7. doi:10.1097/HCO.0000000000000207. PMID 26204494.
- "Obesity and Overweight for Professionals: Causes". Centers for Disease Control and Prevention. Retrieved January 19, 2010.
- "Overweight and Obesity: What You Can Do". Office of the Surgeon General. Retrieved January 19, 2010.
- "Exercise and Bone Health". National Institute of Arthritis and Musculoskeletal and Skin Diseases. 2009. Retrieved February 1, 2010.
- "Osteoporosis — Frequently Asked Questions". United States Department of Health and Human Services. 2009. Retrieved February 1, 2010.
- Natural course and prognosis of intervertebral disc diseases. International Society for the Study of the Lumbar Spine, Seattle, Washington, June 1994.
- "KidsWalk-to-School: Barriers and Solutions". Centers for Disease Control and Prevention. 2008. Retrieved January 25, 2010.
- Commissaris, DA; Huysmans, MA; Mathiassen, SE; Srinivasan, D; Koppes, LL; Hendriksen, IJ (18 December 2015). "Interventions to reduce sedentary behavior and increase physical activity during productive work: a systematic review.". Scandinavian Journal of Work, Environment & Health. 42: 181–91. doi:10.5271/sjweh.3544. PMID 26683116. Retrieved 18 March 2016.
- Shrestha, N; Kukkonen-Harjula, KT; Verbeek, JH; Ijaz, S; Hermans, V; Bhaumik, S (17 March 2016). "Workplace interventions for reducing sitting at work.". The Cochrane database of systematic reviews. 3: CD010912. doi:10.1002/14651858.CD010912.pub3. PMID 26984326. Retrieved 18 March 2016.
- "How can I give my immune system a boost?". National Health Service. Retrieved January 24, 2010.
- Charansonney OL, Després JP (2010). "Disease prevention--should we target obesity or sedentary lifestyle?". Nat Rev Cardiol. 7 (8): 468–72. doi:10.1038/nrcardio.2010.68. PMID 20498671.
- "Physical Activity Statistics". Centers for Disease Control and Prevention. Retrieved January 22, 2010.
- "Statistics on Obesity, Physical Activity and Diet: England, February 2009". National Health Service. Retrieved January 22, 2010.
- Pleis, John R.; Lucas, Jacqueline W.; Ward, Brian W. (2008). "Summary Health Statistics for U.S. Adults: National Health Interview Survey" (PDF). Series Reports from the National Health Interview Survey #10. Centers for Disease Control and Prevention: 11.
- Judson, Olivia (2010-02-23). "Stand Up While You Read This". Opinionator. New York Times.
- Gardner, Amanda (2010-07-27). "Study: The longer you sit, the shorter your life". Health Interactives. USA Today.
- Vlahos, James (2011-04-14). "Is Sitting a Lethal Activity?". Magazine. New York Times.