Sitting is the New Smoking

Introduction

It was Dr. James A. Levine, MD, PhD director of the Mayo Clinic who originally coined the famous term, “sitting is the new smoking”. This is obviously a bold and thought provoking statement, and while the risk factors are not entirely the same, overall inactivity and sitting for long periods of time is a huge concern for good reason! Researchers continue to find more evidence that prolonged sitting (of more than 30min consecutively) increases your risk of developing several serious diseases like Cancer, Heart Disease, Type 2 Diabetes, etc.

Why?

Aside from metabolic syndrome and the obvious weight gain which we know leads to several other major health risks…

When we sit, our large postural muscles (like the quadriceps and gluteal muscles) are inactive and normally when they are working and using energy, they produce an abundance of beneficial molecules in the body. Skeletal muscles are structured like a sturdy rope with lots of fibers and layers all the way down to the microscopic level. The rope “threads” are the thousands of microfibrils in the muscle that contain the smallest cell called sarcomeres. The sarcomeres contain even smaller protein filaments called actin and myosin strands that will shorten against each other starting the contraction within the cell and ignite the sliding filament mechanism (what we know to be the complete process of the muscle contraction). This “rope” or muscle is highly dependable on lifestyle habits. “Aged skeletal muscle produces less force and there is a general “slowing” of the mechanical characteristics of muscle. However, neither reduced muscle demand nor the subsequent loss of function is inevitable with aging. These losses can be minimized or even reversed with training.”1

These skeletal muscles have a powerful electrical activity in them when they’re active and contracting, which I like to think of very similar to a light switch that turns the electricity on, or in this case- a variety of healthy reactions in the muscles and then throughout the body. So adversely, when we are inactive, these reactions are extremely suppressed and the light switch is off.

Within the cardiovascular system specifically… there is a gene that controls inflammation and blood clotting (which helps to keep our circulation efficient), when we are inactive this gene is greatly suppressed. This suppression leads to inflammation build up throughout the body and especially at areas most vulnerable to a chronic inflammatory response such as visceral fat tissue (the fat that surrounds your internal organs). So the longer and more visceral fat you hold, the longer and more susceptible you are to a variety of conditions. “Research has shown that chronic inflammation is associated with heart disease, diabetes, cancer, arthritis, and bowel diseases like Crohn's disease and ulcerative colitis.”2 Because chronic inflammation can linger for such a long time, it is hard to determine if the inflammation is the cause of these outcomes, or a risky byproduct. Which either way, is a dangerous gamble and should be prevented and controlled at all times.

The lymphatic system, which is a driver of the immune system and functions to clear cellular waste and digestive fats, maintain fluid levels, and protect the body from threatening invaders, is also compromised from unchecked inflammation buildup. “When lipoprotein lipase breaks down triglycerides, the fat molecules are used by the body as energy or stored in fatty tissue for later use.”3 So it is an enzyme within the lymphatic system that essentially vacuums the fat out of your bloodstream, and it is almost nonexistent when we are inactive- which leads to around a 75% drop in your ability to not only remove fats, but control cholesterol as well!

The physiological consequences from inactivity truly do outweigh the intent of other potentially beneficial choices. “More than 100 million U.S. adults are now living with diabetes or prediabetes, according to a new report released today by the Centers for Disease Control and Prevention (CDC). The report finds that as of 2015, 30.3 million Americans – 9.4 percent of the U.S. population –have diabetes. Another 84.1 million have prediabetes, a condition that if not treated often leads to type 2 diabetes within five years.”4 this means millions of people are facing this lifestyle disease: something that can be hugely prevented with consistent, healthy habits. We face several other diseases that are either developed as a direct result or progressed by inactivity.

Figure 1 National Diabetes Statistics Report 20204

A workout won’t save you! Research has been shown repeatedly that the harmful effects of long term sitting is not even avoided with daily exercise or all the other health promoting habits such as quality sleep, a nutritious diet, intimate relationships, stress management, and refraining from drugs and alcohol … so you really can’t excuse sitting for hours and general inactivity by making up for it by a tough workout. We have to continually move throughout the day on top of that challenging workout!

How?

Glucose metabolism is improved with just 2min of walking every half hour! “The benefits of such minor behavioral changes could inform future workplace health interventions.”5

I recommend starting out by just setting alarms (preferably a pleasant sounding one to associate movement with rewarding energy) on your phone every half hour to stand up, walk around for a couple minutes, and stretch. It is especially important to keep mobility in your hip flexors by stretching and re-lengthening the group of muscles again. As we sit in a flexed position, our hip flexors are squished in a compressed position, tightening more and more. This will quickly tilt the pelvis, which will force a forward leaning posture. When we hold this inefficient posture for too long (especially one that compresses the spine), it creates back pain!

Tips

Aim for creating an environment that supports movement over sitting.

This can be done by:

• Set your morning alarm 20min before you need to so you can walk outside and adjust your circadian rhythms right away

• Use a standing desk where you work

• Ride a bicycle for short distance errands

• Walk when making phone calls

• Catch up with a friend while going on a walk

• Establish a peaceful yoga/meditation area

• Have mobility tools (foam roller, resistance bands, yoga ball, etc) in the living room so you can move improve mobility while watching tv

• Place a recumbent bicycle in the room you spend the most time in so you can cycle for those few minutes every half hour

• Take your dog on a walk

• Keep a foot massage roller/ball in the bathroom so you can energize through your feet while brushing your teeth

• Use the stairs whenever possible

Too much sitting zaps your energy, creates stiff muscles and joints, and damages your overall health. You control the situation. Create an environment that encourages consistent movement in your day, even if you go to the gym… and especially if you don’t!

References:

1. Kirkendall, Donald T., and William E. Garrett. “The Effects of Aging and Training on Skeletal Muscle.” The American Journal of Sports Medicine, vol. 26, no. 4, July 1998, pp. 598–602, doi:10.1177/03635465980260042401.

2. Publishing, Harvard Health. “Understanding Acute and Chronic Inflammation.” Harvard Health, www.health.harvard.edu/staying-healthy/understanding-acute-and-chronic-inflammation.

3. “LPL Gene - Genetics Home Reference - NIH.” U.S. National Library of Medicine, National Institutes of Health, ghr.nlm.nih.gov/gene/LPL.

4. U.S. Department of Health and Human Services , 2020, National Diabetes Statistics Report 2020. Estimates of Diabetes and Its Burden in the United States.

5. Pulsford, Richard M et al. “Intermittent walking, but not standing, improves postprandial insulin and glucose relative to sustained sitting: A randomised cross-over study in inactive middle-aged men.” Journal of science and medicine in sport vol. 20,3 (2017): 278-283. doi:10.1016/j.jsams.2016.08.012