Active Transportation and Health: Cycling > Walking > Driving

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Photo by Tejvan Pettinger (Source)

Today’s guest post comes from my friend, colleague, and former labmate Richard Larouche.  You can find out more about Richard at the bottom of this post.

Regular readers of Obesity Panacea will know that today’s children are not active enough. For example, according to the 2007-2009 Canadian Health Measures Survey, only 9% of boys and 4% of girls meet the Canadian physical activity guidelines (Colley et al., 2011, available here). These guidelines recommend that children and youth accumulate at least 60 minutes of daily moderate-to-vigorous physical activity – that is activities that are intense enough to increase one’s heart rate and accelerate breathing.

There are many sources of daily physical activity including organized sports, physical education, active transportation, household tasks, etc. Today, I will focus on active transportation, which is the use of non-motorized means such as walking and cycling to travel to and from places.

Travis and I have recently published a comprehensive review of 68 studies that looked at active transportation to and from school among children and youth (Larouche et al., 2014a, available here). To be eligible for the review, studies needed to examine the relationship between active transportation and one of the 3 following outcomes: 1) physical activity; 2) body composition (i.e., body weight and waist circumference); and 3) cardiovascular fitness.

We found consistent evidence that active transportation was associated with higher physical activity levels, not only during the journey to and from school, but during the whole day as well. Furthermore, the difference in physical activity between children using active vs. motorized travel modes was even greater among those who traveled longer distances.

35% of the studies showed that active travelers had a more favourable body composition. However, over half of the studies found no such differences. In our article, we proposed several potential explanations for these findings. I will briefly mention 3 of these hypotheses:

  1. Active travelers may compensate for the increased energy expenditure during active transportation by eating more during the rest of the day.
  2. The energy expenditure of active transportation may simply be insufficient to have a substantial impact on body composition for the typical child who walks or bikes to and from school over a short distance.
  3. Active transportation tends to be more common among children from low socio-economic status families (e.g., families with lower income and/or parental education level). Previous studies indicate that these children are more likely to be overweight or obese.

Finally, for cardiovascular fitness, our findings differed by travel mode. Indeed, the association between walking to and from school and fitness was inconsistent: some studies showed no differences and others found that walkers were slightly fitter. However, all 5 studies that specifically examined cycling found that cyclists were substantially fitter. This included a 6 year longitudinal study which showed that children who switched from motorized travel to cycling increased their fitness over time.

The Canadian Health Measures Survey

More recently, I performed a series of analyses using data from the 2007-2009 Canadian Health Measures Survey (Larouche et al., 2014b, available here). This survey conducted by Statistics Canada is representative of the overall Canadian population.

In the survey, 1,016 youth aged 12-19 years were questioned on the amount of time that they usually spend walking and cycling while traveling to and from school or work or while doing errands. This provided an opportunity to examine active transportation beyond the school trip and how it relates to physical activity, body composition and cardiovascular disease risk factors.

Both walking and cycling were associated with higher physical activity levels, even after controlling for gender, age, parental education and the complex survey design.
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Category: News | 3 Comments

What are your views on moral aspects of sport?

A PhD student at Dalhousie University is studying moral aspects of sport, and he needs your help completing a short questionnaire.  The questionnaire is completed online, and available here.  You do not need to have experience playing sport to participate in this study. Anyone can participate, as long as you can read English and are 18 years of age or older.

A short description of the survey:

Should religious clothing be banned from sports, even if it doesn’t enhance performance? Are initiation rituals inherently wrong? Should coaches value equal playing time above winning? Is fighting in hockey a good thing?  Click here to take a quick survey about moral issues in sport. Your opinions are very important and will help researchers better understand how to promote more civil and productive debates in sport! Email Shea (Sb@dal.ca) for more info! 

Full details can be found here.

Travis

Category: Miscellaneous | Tagged | Comments Off

Kick start your physical activity this spring with the “good enough” workout!

spring exerciseEver notice how much more active you are in the spring/summer? You’re not alone. Research has shown that energy expended during leisure time activity is significantly greater in the warmer months of the year – at least in areas where a distinct four seasons are experienced. In the winter, when you can’t see past the snow outside your window, you’re more likely to reach for the TV remote (and that box of cookies) than to go for a walk outside. Today, you may look at photos of yourself from last August and wonder what the heck happened over the past 8 months. Unless you’re particularly motivated and bucked the trend, you may find your current self but a pasty and pudgy version of last summer’s. For those of us living in southeast Canada, and northeast US – this winter has been particularly rough. So far, the spring has also been underwhelming.

Personally, when I haven’t been able to get a decent workout in a while, as time passes I become progressively less motivated to get back into the exercise routine. With every day of inactivity I sense as though the hurdle that I need to overcome to be active again becomes greater.

Part of the problem is that I enjoy intense workouts. When I take some time off, I know I won’t be able to bring the same level of intensity I did when I was regularly exercising for some time. And this very thought is what discourages me from getting back into it.

Alas, it is time to get moving again. But how to overcome your feeble motivation?
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Category: Physical Activity | 4 Comments

Does sex tonight impact your workout tomorrow?

A commonly held belief among many athletes and coaches (particularly male ones) is that sexual intercourse the evening before a competition spells disaster on the big day. Thus, many high-level athletes practice abstinence prior to competition. Muhammad Ali was an outspoken proponent of this rule, as was Marv Levy, head coach of the Buffalo Bills, who separated his athletes from their partners leading up to the SuperBowl.

In conversations with my male friends, the anecdotal consensus certainly was that any bedroom activity decreased the intensity of next day’s workout. Though, of course, this is MUCH less relevant than it would be to competitive athletes. Naturally, I decided to look into this issue more seriously and see if there is any scientific evidence to back up the idea that knockin’ boots the night before might negatively influence athletic performance.
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Category: Obesity Research, Peer Reviewed Research, Physical Activity | 4 Comments

Morning workout vs breaks from sitting – which is better for blood sugar?


Today’s guest post comes from Dr Meredith Peddie. You can find more on Meredith at the bottom of the post.

“Sitting is the new Smoking”… we’ve all heard it…. It even made an appearance on Criminal Minds last week (sorry New Zealand TV is probably months out of date)… and yes, there is an ever growing number of studies that indicate that people who sit for long periods are at greater risk of developing, and dying from cardiovascular disease, diabetes and cancer.  There are also studies that indicate that people’s pattern of sitting might also affect their risk of diabetes and cardiovascular disease (longer periods of interrupted sitting are worse than short bouts that are regularly interrupted with activity).  However, the vast majority of these studies are observational in nature, meaning that they can’t tell us if changing peoples sitting patterns will actually reduce their risk of developing and dying from the above mentioned diseases.

Unfortunately, a study in which you actually changed peoples sitting patterns and then waited to see if that affected whether or not they would develop cancer or cardiovascular disease would take years, and require a large number of people…. So that is where our study comes in… we decided to investigate whether different patterns of activity and sitting would affect risk factors for cardiovascular disease in a very acute setting.  Specifically, our study was designed to compare the effects of prolonged uninterrupted sitting, a single continuous bout of physical activity combined with prolonged sitting, and sitting with regular activity breaks on postprandial metabolism.  

To do this we conducted a randomized cross over study in which 70 healthy, normal weight men and women participated in three intervention days, one in which they sat continuously for 9 h (except then they had to get up to use the bathroom), one in which they walked briskly uphill on the treadmill for 30 min and then sat for the remainder of the 9 h, and one in which they performed regular activity breaks (1 min and 40 sec walks on the treadmill every half an hour – giving us a total of 30 min on the treadmill over the 9 h) sitting in between each break.

During this time we fed them three times, and collected blood samples at regular intervals for the analysis if glucose, insulin and triglyceride.  – Sound familiar? Yes, our study is very similar in design to a study Travis conducted as part of his PhD, and to the study David Dunstan conducted in Australia, however, the key differences are we used healthy, normal weight adults as participants (not children or overweight adults) and had an intervention day which was designed to mimic someone meeting the current physical activity guidelines, but still spending a lot of time sitting.

What did we find?

Source

Peddie et al., 2013 (Source). Click to enlarge.

Regular activity breaks resulted in a 39% reduction in plasma glucose, and a 26% reduction in plasma insulin when compared to prolonged sitting.  But what was surprising was that we also found a 37% reduction in plasma glucose and an 18% reduction in plasma insulin when regular activity breaks were compared to 30 min of physical activity combined with prolonged sitting. 
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Category: Guest Post, News, Sedentary Behaviour | Tagged | 11 Comments

Watching this interview may be bad for your health

A couple weeks ago I had the pleasure of being interviewed on the local Global TV morning show here in Halifax, talking about the health impact of sedentary behaviour.  It was a fun interview, and we covered a lot of the main reasons why sedentary behaviour is bad for your health. And no, the irony of going on TV to talk about the health impact of TV was not lost on me (sitting is bad for you; sitting in front of a TV is very bad for you).  In particular, the McDonald’s product placement proved my point about the ubiquity of food ads on TV.  I think it went well (Peter told me that I no longer look like a grad student – so mission accomplished!), so I thought I’d post it up here.  Enjoy!

Travis

Category: Interview, News | 4 Comments