Monica Almendras and Erik Peper
Have you ever wondered why after driving long distances or sitting in a plane for hours your feet and lower leg are slightly swollen (Hitosugi, Niwa, & Takatsu, 2000)? It is the same process by which soldiers standing in attention sometimes faint or why salespeople or cashiers, especially those who predominantly stand most of the day, have higher risk of developing varicose veins. By the end of the day, they feel that their legs being heavy and tired? In the vertical position, gravity is the constant downward force that pools venous blood and lymph fluid in the legs. The pooling of the blood and reduced circulation is a contributing factor why airplane flights of four or more hours increases the risk for developing blood clots-deep vein thrombosis (DVT) (Scurr, 2002; Kuipers et al., 2007). When blood clots reaches the lung, they can cause a pulmonary embolisms that can be fatal. In other cases, they may even travel to the brain and cause strokes.
Sitting without moving the leg muscles puts additional stress on your heart, as the blood and lymph pools in the legs. Tightening and relaxing the calf muscles can prevent the pooling of the blood. The inactivity of your calf muscles does not allow the blood to flow upwards. The episodic contractions of the calf muscles squeezes the veins and pumps the venous blood upward towards the heart as illustrated in figure 1. Therefore, it is important to stand, move, and walk so that your calf muscle can act as a second heart (Prevosti, April 16, 2020).
Figure 1. Your calf muscles are your second heart! The body is engineered so that when you walk, the calf muscles pump venous blood back toward your heart. Reproduced by permission from Dr. Louis Prevosti of the Center for Vein Restoration (https://veinatlanta.com/your-second-heart/).
If you stand too long and experienced slight swelling of the legs, raise your feet slightly higher than the head, to help drain the fluids out of the legs. Another way to reduce pooling of fluids and prevent blood clots and edema is to wear elastic stockings or wrap the legs with intermittent pneumatic compression (IPC) devices that periodically compresses the leg (Zhao et al., 2014). You can also do this by performing foot rotations or other leg and feet exercises. The more the muscle of the legs and feet contract and relax, the more are the veins episodically compressed which increases venous blood return. Yet in our quest for efficiency and working in front of screens, we tend to sit for long time-periods.
Developing sitting disease
Have you noticed how much of the time you sit during the day? We sit while studying, working, socializing and entertaining in front of screens. This sedentary behavior has significantly increased during the pandemic (Zheng et al, 2010). Today, we do not need to get up because we call on Amazon’s Alexa, Apple’s Siri or Google’s Hey Google to control timers, answer queries, turn on the lights, fan, TV, and other home devices. Everything is at our fingertips and we have finally become The Jetsons without the flying cars (an American animated sitcom aired in the 1960s). There is no need to get up from our seat to do an activity. Everything can be controlled from the palm of our hand with a mobile phone app.
With the pandemic, our activities involve sitting down with minimum or no movement at all. We freeze our body’s position in a scrunch–a turtle position–and then we wonder why we get neck, shoulder, and back pains–a process also observed in young adults or children. Instead of going outside to play, young people sit in front of screens. The more we sit and watch screens, the poorer is our mental and physical health (Smith et al., 2020; Matthews et al., 2012). We are meant to move instead of sitting in a single position for eight or more hours while fixating our attention on a screen.
The visual stimuli on screen captures our attention, whether it is data entry, email, social media, or streaming videos (Peper, Harvey & Faass, 2020). While at the computer, we often hold up our index finger on the mouse and wait with baited breath to react. Holding this position and waiting to click may look harmless; however, our right shoulder is often elevated and raised upward towards our ear. This bracing pattern is covert and contributes to the development of discomfort. The moment your muscles tighten, the blood flow through the muscle is reduced (Peper, Harvey, & Tylova, 2006). Muscles are most efficient when they alternately tighten and relax. It is no wonder that our body starts to scream for help when feeling pain or discomfort on our neck, shoulders, back and eyes.
Figure 2a and 2b Move instead of sit (photos source: Canva.com).
The importance of tightening and then relaxing muscles is illustrated during walking. During the swing phase of walking, the hip flexor muscles relax, tighten, relax again, tighten again, and this is repeated until the destination is reached. It is important to relax the muscles episodically for blood flow to bring nutrients to the tissue and remove the waste product. Most people can walk for hours; however, they can only lift their foot from the floor (raise their leg up for a few minutes) till discomfort occurs.
Movement is what we need to do and play is a great way to do it. Dr. Joan Vernikos (2016) who conducted seminal studies in space medicine and inactivity physiology investigated why astronauts rapidly aged in space and lost muscle mass, bone density and developed a compromised immune system. As we get older, we are hooked on sitting, and this includes the weekends too. If you are wondering how to separate from your seat, there are ways to overcome this. In the research to prevent the deterioration caused by simulating the low gravity experience of astronauts, Dr. Joan Vernikos (2021) had earthbound volunteers lie down with the head slightly lower than the feet on a titled bed. She found that standing up from lying down every 30-minutes was enough to prevent the deterioration of inactivity, standing every hour was not enough to reverse the degeneration. Standing stimulated the baroreceptors in the neck and activated a cardiovascular response for optimal health (Vernikos, 2021).
We have forgotten something from our evolutionary background and childhood, which is to play and move around. When children move around, wiggle, and contort themselves in different positions, they maintain and increase their flexibility. Children can jump and move their arms up, down, side to side, forward, and backward. They do this every day, including the weekends.
When was the last time you played with a child or like a child? As an adult, we might feel tired to play with a child and it can be exhausting after staring at the screen all day. Instead of thinking of being tired to play with your child, consider it as a good workout. Then you and your child bond and hopefully they will also be ready for a nap. For you, not only do you move around and wake up those muscles that have not worked all day, you also relax the tight muscles, stretch and move your joints. Do playful activities that causes the body to move in unpredictable fun ways such as throwing a ball or roleplaying being a different animal. It will make both of you smile–smiling helps relaxation and rejuvenates your energy.
It is not how much exercise you do, it is how long you sit. The longer you sit without activating your second heart the more are you at risk for cardiovascular disease and diabetes independent of how much exercise you do (Bailey et al., 2019).
Use it or lose it! Activate your calves!
- Interrupt sitting at your desk/computer every 30-minutes by getting up and walking around.
- Stand up and walk around when using your phone.
- Organize walking meetings instead of sitting around a table.
- Invest in a sit-stand desk while working at the computer. While working, alternate positions. There should be a balance between standing and sitting, because too much of one can lead to problems. By taking a short standing up break to let your blood pump back to the heart is beneficial to avoid health problems. Exercise alone, a fancy new ergonomic chair or expensive equipment is not enough to be healthy, it is important to add those mini breaks in between (Buckley et al, 2015).
For a holistic perspective to stay healthy while working with computers and cellphones, see the comprehensive book by Peper, Harvey and Faass (2020), TechStress: How Technology is Hijacking Our Lives, Strategies for Coping, and Pragmatic Ergonomics.
Bailey, D.P., Hewson, D.J., Champion, R.B., & Sayegh, S.M. (2019). Sitting Time and Risk of Cardiovascular Disease and Diabetes: A Systematic Review and Meta-Analysis, American Journal of Preventive Medicine, 57(3), 408-416.
Buckley, J.P., Hedge, A., Yates, T., et al. (2015). The sedentary office: an expert statement on the growing case for change towards better health and productivity British Journal of Sports Medicine, 49, 1357-1362.
Kuipers, S., Cannegieter, S.C., Middeldorp, S., Robyn, L., Büller, H.R., & Rosendaal, F.R. (2007) The Absolute Risk of Venous Thrombosis after Air Travel: A Cohort Study of 8,755 Employees of International Organisations, PLoS Med 4(9): e290.
Smith, L., Jacob, L., Trott, M., Yakkundi, A., Butler, L., Barnett, Y., Armstrong, N. C., McDermott, D., Schuch, F., Meyer, J., López-Bueno, R., Sánchez, G., Bradley, D., & Tully, M. A. (2020). The association between screen time and mental health during COVID-19: A cross sectional study. Psychiatry research, 292, 113333.
Vernikos, J. (2021, February 25). Much ado about standing. Virtual Ergonomic Summit. American Posture Institute. https://api.americanpostureinstitute.com/virtual-ergonomics-summit-free-ticket?r_done=1
Zhao, J.M., He, M.L., Xiao, Z.M., Li, T.S., Wu, H., & Jiang, H. (2014). Different types of intermittent pneumatic compression devices for preventing venous thromboembolism in patients after total hip replacement. Cochrane Database of Systematic Reviews, 12. Art. No.: CD009543.
Zheng, C., Huang, W.Y., Sheridan, S., Sit, C.H.-P., Chen, X.-K., Wong, S.H.-S. (2020). COVID-19 Pandemic Brings a Sedentary Lifestyle in Young Adults: A Cross-Sectional and Longitudinal Study. Int. J. Environ. Res. Public Health. 17, 6035.
 We even wonder if excessive sitting during the COVID-19 pandemic is a hidden risk factor of the rare negative side effects of blood clots in the brain, that can occur with the AstraZeneca and Johnson and Johnson coronavirus vaccine (Mahase, 2021).