Worldwide we have reached an all time high in childhood obesity, occurrence of chronic disease, and sedentary habits. In fact, we as a population have become SO inactive that Health Canada has developed the Sedentary Activity Guidelines – that’s right, a separate set of exercise guidelines for those who are so inactive that the regular physical activity guidelines are just too much. This trend has even carried down to our children, only 7% of children or youth are active enough to meet Canada’s Physical Activity Guidelines and are spending over 62% of their day sedentary, congratulations, this is a great day for us all. From 1980 – 2000 exercise stayed the same, average time per day spend sitting increased by only 8%, and obesity doubled. So, what is the culprit for this radical change in obesity rates in only 20 years?
Sitting at your desk, computer, TV, reading a book, or just plain sitting, is the absolute worst “activity” you can do for your health for many reasons. The amount of time spent sitting is increasing rapidly, in fact, on average humans now spend an average of 9.3 hours per day sitting, this is almost 2 hours more than the average 7.7 hours an average person spends sleeping. That’s right, we spend more time sitting in a chair then we do sleeping and getting rested for the next day. Never in human history have we spend this much time sitting, and it takes more of a toll on your long term health than you think.
If you were to sit down for 1 hour to work or watch your favourite show, this is what happens in your body:
– Electrical activity in your leg muscles shuts off (long term can contribute to sciatica)
– Enzymes that help break down fat reduce by 90% (increasing abdominal fat deposition)
– Metabolism slows down to burn less than 1 Calorie per minute (compared to 3-5 Calories per minute walking)
– Reduction in HDL (good cholesterol) levels
– Compressive forces of about 1700 Newtons (374 lbs) on the lumber spine (lower back)
This all happens within 1 hour of sitting down, so now think about if you are sitting for 8 hours at your job and then more when you come home to watch TV or sit on the computer, even longer periods of sitting start affecting insulin sensitivity, abdominal fat deposition, and more. In fact, people with sitting jobs are twice as likely to develop a cardiovascular disease that someone with a standing job, so if you have a sitting job you should start making a lot more trips to the copier or water cooler throughout the day. On average, people who are obese (BMI over 30 and waist circumference over 102 cm) sit on average 2.5 hours more per day than those with a healthy BMI (between BMI= 20-25). There is a very strong relationship between sitting and obesity along with comorbidities and mechanical stresses on the body (particularly the lower back and neck), so doing everything you can to reduce your time sitting will help reduce your risk for these and will help keep your energy levels and metabolism up throughout the day.
If you don’t think you spend a lot of time sitting, think again, time spent on the computer, TV, reading, or working a desk job with long periods of sitting are all sedentary activity that increases your risk of disease and death. Chances are if you are working a desk job from 9-5 and you aren’t participating in a regular gym routine you may not be getting the recommended 10,000 steps (or equivalent to 30 minutes of moderate intensity physical activity) every day. Even if you do exercise regularly, if you sit for over 6 hours per day you are 40% more likely to die within the next 15 years than someone who sits less than 3 hours per day. Getting the picture? Sitting is horrible for you.
So if you do have a desk job or spend a lot of time seated throughout the day, what can you do to reduce your risk of chronic disease and ward off the negative effects of sitting? Here are some suggestions below that will add a few years to your life (how’s that for anti-aging?):
– Break up long periods of sedentary activity with short bursts of walking or exercise
– Get up every 20 minutes and walk around the office or grab a glass of water (because you probably aren’t getting enough of that in every day either!)
– Do 15-20 squats from your chair followed by 15-20 shoulder blade squeezes every 20-30 minutes, this will help increase blood flow to your lower body and will help with neck pain/tension headaches
– If you have a set of stairs in your building walk up 1 or 2 floors and back down every 20-30 minutes, stairs burn approximately 200% more energy than sitting so it is a great way to boost your metabolism, get your heart rate up, and increase blood flow to your lower extremities
– Wear a pedometer (step counter) or download a pedometer app on your smart phone (a good one is Noom Walk and it counts your steps automatically so you don’t even have think about starting it every morning)
– Try to get 10,000 steps in per day. If you work a desk job try to get 4,000 before lunch and another 4,000 after lunch, then replace a TV show at home with a 20 minute walk, there’s 10,000 steps.
– Go on a brisk walk or do stairs during your lunch break, a great way to burn some extra calories as well as increase energy levels and blood flow into the afternoon
– Interrupt sitting as much as possible – try not to stay seated for more than 20 minutes in a row
– Activate your core while you are sitting and be conscious of slouching or arching your lower back
– Adjust your computer screen so that you are not having to lean forward in your chair while you are working, try to have a 90 degree angle or greater at your hips to improve blood flow to the lower extremities
– Incorporate bodyweight exercises such as chair squats, wall pushups, running on one spot, or balancing on one leg to do to take a break from sitting. Even bring a resistance band or theraband to the office so you can get some reps in throughout the day
– Add trunk extension exercises into your gym routine or even to do before/after work to help strengthen your back and lengthen your spine. Exercises such as bridges, supermans, or bird dog are great for improving posture and reducing the risk of lower back pain.
If you take one message home from this article; spend as little time seated as possible and if you have to be seated, try to stand up and do something active every 20-30 minutes. This will not only reduce your risk of chronic diseases and lower back pain, but will also help keep your energy levels and mood up through the day and prevent the mid-afternoon crash. Start a trend in your office or at your house, get some coworkers to walk with you or do exercises with you and make a competition out of it. Either way, limit sitting as much as possible and make movement a habit, you will be glad you did, and those extra trips to the water cooler could add a few years to your life!
Evan Ward, BScHK, CPT
Presdent & CEO, DYNAMIS
References N Owen, A Bauman, W Brown, Too much sitting: a novel and important predictor of chronic disease risk? (2009) Br J Sports Med 2009;43:81-83 http://bjsm.bmj.com/content/43/2/81.full  J.P. Callaghan, S M McGill, Low back joint loading and kinematics during standing and unsupported sitting (2001) Ergonomics 2001. Feb 20:44 (3): 280-94 http://lib.bioinfo.pl/pmid:11219760  Levine JA, Schleusner SJ, Jensen MD, Energy Expenditure of Non-Exercise Activity (2000) American Journal of Clinical Nutrition 2000. Vol. 72 (6): 1451-1454 http://ajcn.nutrition.org/content/72/6/1451.full  Canadian Sedentary Behaviour Guidelines (2011) Canadian Society for Exercise Physiology (CSEP) http://www.csep.ca/CMFiles/Guidelines/SBGuidelinesBackgrounder_E.pdf