Get Up and Move!: Your Workout Doesn’t Replace Being Active All Day LongPosted: January 3, 2012
From my Healthy Living column in Moncton’s Times & Transcript.
You’re not the typical teenager; you’re a physically active one. After school, you participate in sports nearly each day before sitting down to do your homework and on the weekends, you work out to maximize your athletic performance. Meeting the guideline of a minimum of sixty minutes of physical activity a day isn’t something you need to worry about. You’re definitely not sedentary. Or are you? It turns out that even if you engage in regular physical activity, if you spend the majority of your day engaged in sedentary behavior rather than moving around, you’re increasing your risk of sedentary-lifestyle related diseases.
What exactly is sedentary behavior? The amount of energy you burn while doing various activities is measured in metabolic equivalents (MET). While sitting or lying at rest, you are expending 3.5 mL per kilo of body weight or one MET. You are considered to be engaging in sedentary behavior anytime when you are using less than 1.5 MET. A study, published in 2009 in the journal of Medicine & Science in Sports & Exercise, conducted on 17 000 adult Canadians aged 18 to 90 found that those who spent more time engaged in sedentary behavior were 50% more likely to have died before the end of the follow-up period of the study, independent of their age, smoking, and physical activity levels.
Yikes! It’s possible to sit too much, even if you are physically active enough. That’s a scary thought. While it isn’t understood why this might be true, researchers at the University of Massuchusetts found that even a few days of bed rest significantly increased insulin resistance and levels of plasma triglycerides (blood lipids or fats) in healthy adults.
Currently, Canadian children engage in sedentary behavior for over 70% of the typical school day and the hours Canadian adults spend engaged in sedentary behavior is close to ten. Travis Saunders, a Ph.D candidate in exercise physiology in Ottawa and author of an article on the subject published in the Canadian Diabetes Association’s The Diabetes Communicator newsletter, says that because of the important consequences sedentary behavior may have on public health, guidelines regarding sedentary behavior will likely soon be developed. There are currently guidelines regarding screen time for kids, which suggests limiting it to less than two hours per day.
Meanwhile, we should consider different ways that we can reduce the time we spend engaging in sedentary behavior. We can’t stop going to school or quit our desk jobs. However, what we can do is modify our workstations so that they favor a slightly higher level of activity (e.g. standing up during meeting with colleagues, sitting on exercise balls instead of chairs, or replacing a traditional desk with a standing desk) and take breaks from sitting down occasionally throughout the day.
Originally published in the Times & Transcript on October 29th, 2011.