We should arrive in this world with a note tacked on our cute little human hiney:
Warning: Too much sitting may be
hazardous to your health
Except it’s more than ‘may be hazardous’. There’s a mountain of evidence that it definitely is hazardous to your health to sit too much.
Dang. Just when you got clear on what you need to be sure to include in your workouts, you find out there’s something else that you need to leave out. And that something else is, simply, sitting too much. Being planted firm on your backside for extended periods of time – as in 3 hours at your computer without a break - racks up the disease risk and mortality biomarkers like crazy.
The good news is, it’s an easy fix.
First, I’m going to tell you about the latest discoveries about ‘sitting too much’ and it’s impact your your health. In short:
Sitting too much is not the same
as exercising too little.
Then, I’ll give you some easy-fix solutions so you can turn it around.
It ain’t new. Surprisingly, as far back as the 17th century, physician Bernardo Ramazzini noted the relationship between sedentary behavior and harmful consequences to health. We now know without a doubt that sedentary behavior has its own set of special effects on human metabolism, physical function, and health outcomes. It’s not enough that we’re getting your workouts in. We also need to take a serious look at the size of those chunks of time we spend sitting and reclining.
Sedentary: A definition
Not long ago, when we referred to someone as sedentary, it meant that they were not getting much physical activity. So if, for example, you were exercising for an hour or so a day, you could call yourself physically active. You would be called sedentary if you only got a few minutes of activity on a regular basis.
But this view is changing rapidly as researches discover that sedentary time is positively related to health risk regardless of how much physical activity you get in every day. In this case, positive is not good.
Yes, it has a name! Too much sitting has its own pathology. Recent evidence suggests that sedentary behavior has a direct influence on metabolism, bone mineral content, and vascular health.
5 damaging physiological effects of sedentary behavior
Too much sitting leads to the following, all of which increase the metabolic risk factors for type 2 diabetes and coronary heart disease, independent of the body-protective properties of structured exercise.
- increased triglyceride levels
- decreased levels of high-density lipoprotein (HDL) cholesterol (the ‘good’ cholesterol)
- decreased insulin sensitivity
- metabolic syndrome
- suppressed lipoprotein lipase (LPL) activity in skeletal muscle, the rate-limiting enzyme for hydrolysis of triglyceride (TG)-rich lipoproteins.
Remember, lipoprotien lipase is an enzyme that has the job of extracting particles of fat in your blood and transporting them to one of two places: To your fat cells for storage or to you muscle cells to be used for energy. Physical activity slows down the LPL in fat tissues – making it harder to store fat – and increases LPL activity in the skeletal muscle, pushing fat into the muscle cells to be used for energy. This is obviously desireable. On the other hand, physical inactivity does the opposite, increasing your body’s activity in the fat tissue and slowing it down in the muscles. The result? You store fat more easily. Oh great.
Are you a sedentarist?
Geez, another new word! Are you a sedentarist?
Whereas sedentary is a distinct class of behaviors such as sitting, passively watching TV, and driving, for all activities characterized by little physical movement and low energy expenditure – we now have the new vocabulary kid on the block: Sedentarism. Sedentarism refers to extended engagement in sedentary behaviors. A sedentarist would thus be someone who spends extended periods of time with minimal movement, low energy expenditure, and rest. Unbroken periods of inactivity.
An eye-opening study was conducted to examine the effect of just 5 days of complete bed rest on the metabolic health of 22 adult volunteers. The participants stayed in bed for over 23.5 hours a day.
At the end of the study, though there were no changes in body weight, they experienced significant jumps in total cholesterol, triglycerides, glucose, and insulin resistance. After just 5 days! Changes in carbohydrate metabolism were sharp: Participants experienced a 67% greater insulin response to a glucose load following the 5 days. This suggests that an extended dose of sedentary behavior can lead to a dramatically increased metabolic risk. Other studies have delivered similar results. In 1998, Yanagibori et al. found that 20 days of bed rest also resulted in a significant rise in plasma triglycerides and a big drop in HDL cholesterol (the ‘good’ cholesterol). These findings are further corroborated by reports suggesting that people with spinal cord injuries, a condition characterized by large amounts of time spent sedentary, also suffer from an increased risk of cardiovascular disease (Bauman and Spungen 2008).
Active couch potatoes, take note!
Does it matter how many chunks of sedentary time we have in the day? No doubt. These are the questions that researchers are eager to address as we move forward in the prevention of this growing modern health menace: Inactivity physiology and health risks for the sedentarian, regardless of how well they are at getting their scheduled workouts in. What’s an active couch potato? Someone who does their workouts and then sits around the rest of the time. One active hour out of 24, with a few incidental steps in between.
What we DO know is that sitting for extended periods of times makes a mess of things. What we don’t know specifically are the exact guidelines as as to how to get out of this mess. But we DO know enough to make a difference.
Here comes the easy fix part! 5 simple ways to break out of sedentarism to – what’s the opposite of sedentarism? Activism?
1) Break it up with a few minutes of moving. Experts agree that you can offset this growing sedentary scourge by getting up and moving around for a few minutes every hour, or even better, every 30 minutes. Then do it again after another 30 to 60 minutes. Avoid spending big chunks of time sitting. Squeeze in 5 – 10 minutes of working out. Treadmill, exercise bike. Fit Quickies. A few yoga moves. Stand and do some dumbbell curls. You get the idea.
2) Break it up with a few minutes of standing. True story! Standing elicits a metabolic response stronger than do sitting and reclining. The postural muscles jump into play with stabilizing isometric contractions. In studies of rats who were forced to be inactive, it was discovered that the leg muscles responsible for standing almost immediately lost more than 75 percent of their ability to remove harmful lipo-proteins from the blood. To show that the ill effects of sitting could have a rapid onset in humans too, researchers recruited 14 young, fit and thin volunteers and recorded a 40 percent reduction in insulin’s ability to uptake glucose in the subjects — after just 24 hours of being sedentary. Simply standing more during the day has a payoff in offsetting metabolic problems of being over-sedentary. Try standing for phone calls and water breaks.
3) Get an adjustable height work station. This is a whole new trend in the workplace. Standing workstations give you the option of alternating standing and sitting positions for computer work. Most of these work desks can be raised and lowered so if you become fatigued from too much standing there is an option to lower and sit in a chair to continue work.
4) Spend some of your desk sitting time on a physioball. These invoke engagement of your core muscles to maintain balance and also inspire erect posture, eliciting muscles in the back to come into play too.
Fit Quickies to the rescue!
When I created Fit Quickies, at first I wanted to find a way to not only stay in shape while traveling, but to keep my shape. There is a difference. The Fit Quickies combination of targeted muscle challenge and shaping combined with a challenge to the entire body turned out to be a perfect match.
Then, as part of my ongoing research, I discovered growing evidence explaining how accumulated shorter, intermittent workouts through the day delivered the same benefit of larger, extended workout sessions. And in some ways, uploaded movement throughout the day via Fit Quickies surpassed my initial expectations by their power to also:
- boost brain power and willpower
- create accumulated exercise time over the course of the day, and now
- offset inactivity physiology.
Where to go from here
You know I like to keep it simple. Here’s what you can do to avoid the dangers of sedentarism, or inactivity physiology.
Step 1) Be aware. Start with on overview and assessment of your typical day. How do you measure up? Does your day look something like this: You get up at 6:30, get in the car for an hour’s drive by 7:30, and arrive at your desk at 9:00, sit for 3 hours, break one hour for lunch, sit for 4 more hours, drive an hour home, eat dinner (sitting down), get a 30 minute walk in and then spend the evening witha book or some kind of screen time (computer, TV, movie) sitting or reclining? Then you can proudly call yourself a sedentarist! If you prefer, Active Couch Potato. You got your 30 minute walk in, right? Isn’t that the minimal guideline for healthy adults? You have to look at the entire picture. The damaging effects of all that sedentary time create a problem of their own, and though the walk helped, it doesn’t cancel out, apparently, the health damaging effects of hours of sitting.
Step 2) Upload bits of movement throughout the day. Let’s take the same day outlined above and look at some ways to get in some activity to break up the big chunks of sedentary.
In the workplace:
6:15 While breakfast cooks, stay standing and do 20 knee lifts, and calf raises (Fit Quickie #10).
7:30 In the car on the way to work: Fit Quickie #1, 7 Seconds to a Flat Belly (you can easily do this seated at stoplights. Yes, you’re still sitting but you are actively engaging muscle.)
9:00 Seated at desk
9:45 Go to the most distant restroom for a pit stop. Climb the stairs to the next floor and use the powder room there.
10:30 Walking water bottle break for 2 minutes, followed up with Fit Quickie #9, Stand-up Seat, by your desk
11:15 Repeat 9:45
See where we’re going with this? During the course of the day, get creative about how to sneak in non-sedentary bursts. Stand rather than sit during phone calls. Take a short walk with every water break
Model program for in your home office:
It’s even easier to adjust to your body’s need for regular movement (now that we’ve got THAT settled!) when you work from home. Simply set a timer near your workstation, put an alert on your computer or iphone. Set it for every 30, 45, or 60 minutes. When that chime rings, it is your cue to love your body!
One of my favorite ways to do this is to pick a Fit Quickie or two. These are always fun and instantly invigorating. An all-over energizer like Fit Quickie #10, Leg Plays, never fails to get me going. I’ll often get so energized I’ll go right into #9, Stand-up Seat. These two combined are finished in about 7 minutes. An hour later? Standing version of Fit Quickie #2, Inner Thigh Squeeze and Tease, including the stretch. This is an excellent warm up for #5, Topless Muffins. 5 minutes later, done. An hour later, a set of Perfect Planks (Fit Quickie coming down the pike!) and a 3 minute walk – quick chores around the house, up to the mailbox, set up the rice cooker for lunch, get the potatoes soaking for dinner, empty the dishwasher (remember, standing trumps sitting when it comes to metabolic function!) And here’s the beauty of this pattern. By the time the sun sets, I’ve gotten in an hour of purposeful, body-shaping exercise AND I’ve accomplished the mission of offsetting sedentarist habits by being an ‘all day activist’! I have actually come out ahead of where I would have been if I sat all day and then did the hour long workout on its own. If you have time for both, all the better. But if not, you’ve successfully moved yourself out of the land of”Active Couch Potato”. Beautiful!
The 17,000 Canadians study
Here’s another example to further drive the point home. In 2009 Dr Peter Katzmarzyk and colleagues at the Pennington Biomedical Research Center published a paper that examined the links between time spent sitting and mortality. This study included 17,000 people. The found that time spent sitting was associated with increased risk of all-cause and cardiovascular disease mortality (excluding deaths due to cancer).
But here’s the kicker. The relationship between sitting time and mortality was independent of physical activity levels. In fact, subjects who sat the most were give or take 50% more likely to die during the follow-up period than individuals who sat the least. This was even after controlling for age, smoking, and physical activity levels. and independent of body weight.
So, do those little breaks really make a difference?
Yes. New evidence also suggests that in addition to the quantity of sedentary time, the quality of sedentary time may also have an important health impact. To illustrate, in the Australian Diabetes, Obesity and Lifestyle Study, A total of 168 men and women aged 30-87 years wore an accelerometer (measure of bodily movement) during all waking hours for 7 consecutive days. This way researchers were able to quantify the amount of time that participants spent being sedentary. It also told them how frequently the subjects punctuated sedentary activities with light activity, such as standing and walking to the restroom.
What do you think they discovered? There was a direct correlation between the number of breaks taken from sitting behavior. The more active breaks, the lower the waist circumference, body mass index (BMI), glucose tolerance, and blood lipids. Among nearly 9,000 Australians, for each additional hour of television a person sat and watched per day, the risk of dying rose by 11 percent.
And get this. Even if the total amount of sedentary and physical activity time were equal between individuals, those who took more frequent breaks during their while watching television or at work were less obese and had better metabolic health. And it wasn’t all the much time and effort involved. The breaks taken by the individuals in this study were short – less that 5 minutes – and of low intensity, such as light walking or simply standing!
I don’t know about you, but this little nugget got me up of my chair, out the door to the deck, and on a 3 minute walking break. Easy fix.
All things being equal – age, gender, physical activity, body weight, smoking, alcohol intake, age, and sex - the person who sits more is at a higher risk of disease and death than the person who sits less.
Many questions remain. What is the balance breaking point between sedentary periods and active breaks? What are the other dependent factors, such as level of fitness? What’s crystal clear is that we need to spend fewer chunks of extended time sitting, and keep necessary work or play periods that may be necessarily more sedentary in nature punctuated with light activity. Your body and your brain will thank you.
Thanks so much for coming by. Please join me also on facebook.
Hamilton Mark T., Deborah G. Hamilton and Theodore W. Zderic. Role of Low Energy Expenditure and Sitting in Obesity, Metabolic Syndrome, Type 2 Diabetes, and Cardiovascular Disease. Diabetes November 2007 vol. 56 no. 11 2655-2667.
Hamilton, Mark T. and Lionel Bay. Suppression of Skeletal Muscle Lipoprotein Lipase Activity During Physical Inactivity: A Molecular Reason to Maintain Daily Low-Intensity Activity. The Journal of Physiology, September 1, 2003.
Healy, Genevieve N. MPH, David W. Dunstan, PH, Jo Salmon, PHD, Ester Cerin, PHD, Jonathan E. Shaw, MD, Paul Z. Zimmet, MD and Neville Owen, PHD. Breaks in Sedentary Time: Beneficial associations with metabolic risk. Diabetes Care, February 5, 2008, doi: 10.2337/dc07-2046
Katzmarzyk, Peter T., Timothy S. Church, Cora L. Craig, and Claude Bouchard. Sitting Time and Mortality from All Causes, Cardiovascular Disease, and Cancer. Medicine and Science in Sports, and Cancer.
Murphy M, Nevill A., Neville C., Biddle S., Hardman A. “Accumulating brisk walking for fitness, cardiovascular risk, and psychological health.” Med Sci Sports Exerc. 2002 Sep;34(9):1468-74
Schmitz, Charlotte J. Standing Up for Workplace Wellness. Ergotron, Inc., 2011.
Saunders, Travis. Can Sitting Too Much Kill You? Scientific American, January 6, 2011.
Tremblay MS, Colley RC, Saunders TJ, Healy GN, Owen N. Physiological and health implications of a sedentary lifestyle. Appl Physiol Nutr Metab. 2010 Dec;35(6):725-40.
Zderic, Theodore W. and Marc T. Hamilton. Physical inactivity amplifies the sensitivity of skeletal muscle to the lipid-induced downregulation of lipoprotein lipase activity. Journal of Applied Physiology January 2006 vol. 100 no. 1 249-257.