You may have heard about some of the recent studies showing that sitting for extended periods each day increases the risk of illness and death. But did you know that scientists have estimated that nearly 10 percent of all deaths in the world are likely caused by sitting too long? That is a full 5 million deaths per year – caused by extended sitting.
A number of studies have shown this too. By the way, this is called all-cause mortality – meaning death from any cause.
Death by sitting
One of the more recent studies showing this comes from universities in Portugal and Spain that studied a population of 611 people over the age of 60 years old. The study followed this group of adults for ten years. They found that 77 percent more deaths occurred for those who sat for more than eight hours per day.
Furthermore, they found that those who sat for less than eight hours and were moderately active – they exercised – had a 50 percent less incidence of death during the ten years. Furthermore, those who did both – they exercised plus they sat for less than eight hours a day – had a 68 per cent reduced incidence of death during the study.
Another recent study offers us more information. This one comes from a collaboration of researchers from the UK’s Loughborough University, the University of Sydney, San Diego State University and University College London. This study followed 201,129 adults for nine years. They were 45 years-old and older, all living in New South Wales, Australia.
During the study period, 7,460 people died
The researchers correlated their average time sitting. They also calculated their average per-day activities – including standing time, walking time, exercising (moderate-to-vigorous), and sleeping time (among those who slept less than 7 hours per day).
The research found that all of these activities – including sleeping – decreased the incidence of death compared to sitting during the 9-year study. The researchers calculated the death risk on a per hour-per day basis, for an activity that replaced sitting. Here is how it went:
• Every hour per day spent standing instead of sitting reduced the risk of death by 5%
• Every hour per day spent walking instead of sitting reduced the risk of death by 14%
• Every hour per day spent exercising instead of sitting reduced the risk of death by 12%
• Every hour per day spent sleeping instead of sitting reduced the risk of death by 6%
Yes – even sleeping is better than sitting according to this gigantic study!
The sitting time calculated in this study – as most do – combined time sat while working, sitting at the computer, watching TV and otherwise. It was called “total sitting time.”
Depending upon the type of exercise, those who replaced sitting with exercise had a reduced risk of death that ranged from 7 to 18 percent for every hour per day.
This of course also meant that two hours spent exercising rather than sitting each day would result in between 14 and 36% reduced risk of death.
And this is death from all types of disease.
Other studies done on this topic have shown similar results. And other researchers have reviewed these studies and found they all confirm the results.
Even fidgeting is better than sitting motionless
Another recent study, from the UK’s University of Leeds, studied sitting time along with fidgeting time and other activities. Using the Women’s Cohort Study that gathered information from more than 35,000 women – this study followed 12,778 women between 37 and 78 years old. The women were followed for twelve years and monitored to their average sitting time per day, along with diet, alcohol consumption, smoothing and other risks of increased death.
The study also followed the subjects for all-cause mortality – deaths during the study from any cause.
The researchers found that sitting for more than seven hours per day resulted in a 30 percent increased incidence of death – but only among women in the group that did not fidget much when they sat.
The researchers called this the low-fidgeting group.
Now the high-fidgeting group saw an altogether different result from their sitting. The researchers found that high-fidgeting women who sat for between five and six hours per day were 37 percent less likely to die. This is compared to those high-fidgeting women who sat for less than five hours per day.
Okay, let’s get this straight: While sitting longer among most people results in a greater risk of death – those who fidget a lot have a reduced risk of death when they sit longer.
The researchers also found a similar relationship among those who sat for extended periods:
“There was no increased mortality risk from longer sitting time in the middle and high fidgeting groups.”
Of course, this goes completely against the relationships found in so many other studies – that each hour more of sitting results in greater risk of death. The researchers confirmed this in their conclusion:
“Fidgeting may reduce the risk of all-cause mortality associated with excessive sitting time.”
Diseases linked to sitting
A number of specific diseases have been linked to sitting. These include cancer, cardiovascular disease (heart and blood vessels), diabetes, pulmonary diseases (lungs), joint and muscle pain, back pain, neurological conditions and many others.
Why are so many diseases – and death – related to sitting?
The question now becomes, why is motionless sitting so bad? This concept of fidgeting reducing the risks linked with sitting changes the question from sitting to motionless sitting: Why?
Most credit it all to circulation. They state that sitting reduces the blood flow and this causes the various problems associated with sitting. They say that because sitting blocks blood flow in certain ways, there is the increased risk.
But if this were completely so, then standing should completely reverse the risks of sitting – which it doesn’t. As shown in the study above, standing only reduces the effects of sitting by 5%. This is quite a bit less than the reduced effect of fidgeting.
In fact, another 2015 study from the UK’s University of Bedfordshire studied breaking up sitting time with walking or standing. They found that getting up and walking around does partially offset the damaging effects of sitting, but standing does not.
Certainly, we cannot discount the role of increased circulation too much. Increased blood flow might account for some of this – but certainly not all or even most of it – since fidgeting reduced the risk of sitting by a lot more than walking for example.
The reason is the lymphatic system. Our lymphatic system is a system of vessels that might be compared to blood vessels in that they exist throughout the body. But they are dramatically different than blood vessels. They don’t pump blood around. They pump lymph.
What is lymph?
Lymph is primarily a mix of immune cells and those broken down cells and toxins the body and the immune system wants to get rid of.
Yes, the lymphatic system is our primary circulation for our immune system. The lymphatic system delivers our T-cells and B-cells and associated elements to sites that are damaged or infected.
Yes, some of these elements are also delivered within the blood. But the lymphatic system is the immune system’s primary route for circulation.
Once T-cells and B-cells take apart infected and diseased cells and invaders, they are deposited into the lymph and to a lesser degree, the blood – and transported out of the body. Sometimes the lymphatic system will collect these within glands – where they will be transported through other excretory systems. But glands will also provide pools of immune cells and even probiotic bacteria in some cases as well.
So what’s lymph have to do with fidgeting?
The blood is pumped around the blood vessels of the body by the heart. This is combined with vascular scaffold pumping as well – to bring blood up from the feet. But the heart does most of the work of blood circulation.
So where is the pump of the lymphatic system? The pump of the lymphatic system is our muscular system. Lymph vessels and glands are positioned between and around our muscles in such a way that as we flex our muscles, our lymph is circulated.
So fidgeting is basically flexing some of our muscles – which has the effect of pumping our lymphatic system – thereby circulating our immune system through our body.
This means that not only will fidgeting help reduce the damaging effects of sitting – but so will exercise, or even walking. These help because they flex our muscles and thus circulate stagnated lymph.
So fidget a little – and flex as you read this.
Martínez-Gómez D, Guallar-Castillon P, Mota J, Lopez-Garcia E, Rodriguez-Artalejo F. Physical Activity, Sitting Time and Mortality in Older Adults with Diabetes. Int J Sports Med. 2015 Sep 2.
Stamatakis E, Rogers K, Ding D, Berrigan D, Chau J, Hamer M, Bauman A. All-cause mortality effects of replacing sedentary time with physical activity and sleeping using an isotemporal substitution model: a prospective study of 201,129 mid-aged and older adults. Int J Behav Nutr Phys Act. 2015 Sep 30;12:121. doi: 10.1186/s12966-015-0280-7.
Hagger-Johnson G, Gow AJ, Burley V, Greenwood D, Cade JE. Sitting Time, Fidgeting, and All-Cause Mortality in the UK Women’s Cohort Study. Am J Prev Med. 2015 Sep 4. pii: S0749-3797(15)00345-1. doi: 10.1016/j.amepre.2015.06.025.
Benatti FB, Ried-Larsen M. The Effects of Breaking up Prolonged Sitting Time: A Review of Experimental Studies. Med Sci Sports Exerc. 2015 Oct;47(10):2053-61.
Brink Y, Louw QA. A systematic review of the relationship between sitting and upper quadrant musculoskeletal pain in children and adolescents. Man Ther. 2013 Aug;18(4):281-8. doi: 10.1016/j.math.2012.11.003.
Strobl WM. Seating. J Child Orthop. 2013 Nov;7(5):395-9. doi: 10.1007/s11832-013-0513-8.
Cerimele JM, Katon WJ. Associations between health risk behaviors and symptoms of schizophrenia and bipolar disorder: a systematic review. Gen Hosp Psychiatry. 2013 Jan-Feb;35(1):16-22. doi: 10.1016/j.genhosppsych.2012.08.001.
Hunt T, Madigan S, Williams MT, Olds TS. Use of time in people with chronic obstructive pulmonary disease–a systematic review. Int J Chron Obstruct Pulmon Dis. 2014 Dec 12;9:1377-88. doi: 10.2147/COPD.S74298.
MacEwen BT, MacDonald DJ, Burr JF. A systematic review of standing and treadmill desks in the workplace. Prev Med. 2015 Jan;70:50-8. doi: 10.1016/j.ypmed.2014.11.011.
Bailey DP, Locke CD. Breaking up prolonged sitting with light-intensity walking improves postprandial glycemia, but breaking up sitting with standing does not. J Sci Med Sport. 2015 May;18(3):294-8. doi: 10.1016/j.jsams.2014.03.008.
Prince SA, Gresty KM, Reed JL, Wright E, Tremblay MS, Reid RD. Individual, social and physical environmental correlates of sedentary behaviours in adults: a systematic review protocol. Syst Rev. 2014 Oct 21;3:120. doi: 10.1186/2046-4053-3-120.
Adams C. Boosting the Immune System: Natural Strategies to Supercharge our Body’s Immunity. Logical Books, 2013.