Friday, February 5, 2016

Are Canadian children in a physical activity crisis?

By Brian Timmons, PhD

There is an activity crisis in Canada. Canadian kids do not get enough physical activity for healthy growth and development. How do I know? Because according to the ParticipACTION Report Card on Physical Activity for Children and Youth only 9% of kids ages 5 to 17 meet the Canadian physical activity guidelines. We are raising a generation of children that will not outlive their parents. It's serious.

In a couple of weeks, I will be speaking at the Chronic Disease Prevention Alliance of Canada (CDPAC) conference in Toronto. My presentation is in the last session on the last day of the conference (a coincidence, I'm sure). Not to steal my own thunder, but in that presentation I will suggest that the physical activity landscape among children in this country may not be as bleak as we are led to believe.

To do so, we have to start at the beginning. How much physical activity do kids need for healthy growth and development? Do you follow twitter? Are you on the Facebook (yes, I call it "the" Facebook)? Lots of organizations insist that kids "need" 60 min every day. Do you check out ParticipACTION much? The message is the same: kids need 60 min every day. Even the World Health Organization recommends 60 min of physical activity every day. And if kids don't get it? Well, that's when the crisis sets in. Of course, these recommendations are based on the evidence, right?

A reasonable question at this point would be: what does the evidence say? Let's take the Canadian situation. The current Canadian physical activity guidelines are based on the evidence synthesized in a systematic review conducted by Janssen and LeBlanc. What did these authors find? They wrote, "The minimal and optimal doses of physical activity required for good health in children and youth remain unclear". They went on to write, "The need for children and youth to engage in physical activity on a daily basis to maintain good health was not supported by the evidence reviewed here". Indeed, recommendation #1 from these authors was: "Children and youth 5-17 years of age should accumulate an average of at least 60 minutes per day and up to several hours of at least moderate intensity physical activity". An "average" of at least 60 min per day. Not 60 min every day. And the reason they didn't recommend the latter is because there is no evidence for it. They didn't even say it had to be moderate to vigorous physical activity (MVPA), just, "at least moderate".

So how did our Canadian physical activity guidelines come to read 60 min of MVPA every day? You can read about that here.

Then there is the problem of measurement. The statistic that only 9% of Canadian school-aged children meet the guidelines is based on data from the Canadian Health Measures Survey (CHMS). The CHMS uses accelerometry (which has its own issues; dare I say "epoch") to objectively monitor physical activity of its participants. Unfortunately, the rigid definition of the guideline creates a disappointing number of kids who are actually active 60 min at a moderate to vigorous intensity every day.

But wait. Is it all that bad?

What is often lost in the publications and press releases is the finding that 61% of kids accumulate at least 60 min of MVPA on at least 2 days of the week and that 44% of kids accumulate at least 60 min of MVPA on at least 3 days of the week. Why is this important? Well, because Janssen and LeBlanc wrote, "there is strong and consistent evidence based on experimental studies for several health outcomes that participating in as little as 2 or 3 hours of moderate-to-vigorously intense physical activity per week is associated with health benefits". And remember, experimental studies are usually those that impose physical activity on top of the child's normal activity routine. One interpretation, therefore, is that the majority of Canadian kids are, in fact, active enough for health, isn't it? Another finding from the 2007-2009 CHMS that never appears on twitter is that almost 50% of Canadian kids accumulate at least 30 min of MVPA on at least 5 days of the week. This fits into Janssen and LeBlanc's evidence-based statement of 2 to 3 hours of MVPA per week as well, doesn't it?

And 50% is better than 9%.

But wait, there's more...

There are also Canadian physical activity guidelines for the early years (0-4 years), and I can proudly say I was involved in their development. These guidelines recommend that children ages 1 to 4 years should accumulate at least 180 min of physical activity at any intensity every day. Is this evidence-based? Well, you can read about that here. The important question is what proportion of Canadian preschoolers meets these guidelines? The CHMS says 70%. Hardly a crisis.

So where does this leave us?

As a father of 3 kids between the ages of 5 and 17 years, I guess I wonder is 60 min of MVPA every day necessary for their healthy growth and development. If they only get an "average" of 60 min of MVPA on any given week (meaning some days may be more active than others), does this have major implications for their health? If occasionally they spend all day indoors and play video games or board games, does that make me a bad parent? As a scientist, I wonder the same: is 60 min of MVPA every day necessary for children's healthy growth and development? I wonder if the way we measure adherence to the guidelines and the guidelines themselves are flawed to a point where our interpretation is tainted. I wonder what the scientific community can do to avoid the activity crisis rhetoric. Government and non-government agencies are investing in initiatives designed to promote physical activity, in part, because of the apparent activity crisis. Are these initiatives needed it? Are they worth it? If you're in Toronto this year on February 25th, drop into our symposium Thursday afternoon to find out.

Do I think more is better when it comes to physical activity for kids? Yes.

Do I think Canadian children are in a physical activity crisis? No.

Friday, September 4, 2015

Do 70% of kids actually drop out of sports by the age of 13?

By Brian Timmons, PhD

70% of kids drop out of sports by the age of 13. Really? When I read that statistic I was intrigued, so I investigated. What I found was surprising.

The first time I saw that statistic was last year in an article entitled: "Why kids quit sports" – a post on the Active for Life website. After several email communications, that story has since been revised, but at the time, one of the statements in this post that tweaked my interest was the following: "... of the 20 million kids in the U.S. that sign up yearly for team sports like hockey, soccer, and baseball, almost 70 percent will quit by the time they're 13. The number of kids in Canada is different, but the percentage is the same."
Photo by Edward N. Johnson / CC BY 2.0 

The statement now reads, "...of the 20 million kids in the U.S. that sign up yearly for team sports like hockey, soccer, and baseball, almost 70 percent will quit by the time they're 13 (according to Michigan State University). The number of kids in Canada is different, but it's reasonable to assume the percentage is similar." (At least that’s what it read at the time I wrote this).

I had 2 problems with the original, and the revised, statement. First, I thought the 70% drop-out statistic seemed high. Second, I was not aware of similar Canadian data, even though the author of the post first seemed sure and later thought it reasonable that the percentage is the same in Canada.

Welcome to “Axioms & Advocacy”, a blog about child health and exercise medicine

By Brian Timmons, PhD

A blog can be defined as a regularly updated website or web page, typically one run by an individual or small group that is written in an informal or conversational style. Now, I know that many people will wonder how it is possible that I am "blogging". I've been accused of tweeting more than I talk... and I usually don't talk that much. So, why do individuals or small groups begin to blog? Some of the reasons include: to express thoughts and opinions; to market or promote something; to help people; to establish oneself as an expert; to connect with similar people; to make a difference; to stay active or knowledgeable in a field or topic; to stay connected with friends and family; to make money; to have fun and be creative. I guess some of these reasons apply to me, too.

If you become a follower of this blog (what is the word for blog followers anyways?), you can expect to read about child health, fitness and physical activity, nutrition, and lots of topics that generally speak to healthy active living during the growing years. What else can you expect?

I will definitely express thoughts and opinions (backed by evidence at all costs); I'll probably promote something at some point (most likely evidence); I can only hope that something I post will help another person; self-proclamation of expertise? (don’t take my word for it, tune in and decide for yourself); I will be grateful for your comments and connections; I'm assuming writing this blog will make a difference in my free time; they say variety is the spice of life, and we will cover a lot of topics; I guess it’s possible that friends and family will read this blog, but I'm not counting on it; you can make money writing a blog?; creativity is NOT my middle name, but I do hope we can have some fun.