To exercise when it is cold or rainy or not to exercise?  That is the question.  Not for Hamlet but apparently it is for Canadian adolescents. 

Researchers at McGill University in Montreal looked at what, if any, influence weather and season have on physical activity levels for boys and girls from about age 12 to age 17.  They tracked the number of physical activity sessions per day in a group of students and correlated activity level with the daily weather conditions.  They found that for each four-inches of snow accumulation the students had 3% fewer activity sessions.  Similar drops in activity were seen on days with significant (10 cm or about 4 inches) rainfall.  For every 10 degrees Celsius (about 18 degrees Fahrenheit) increase in temperature, researchers saw a nearly 6% increase in daily physical activity sessions. 

Now this could be another one of those “duh” stories, especially for those of you living this time of year in the cold, damp, and dark of the northern latitudes.  But one of the most significant findings of this study was that the increases that occurred in the warmer months did not compensate for the declines that occurred during the winter.  This led to a net decline in physical activity sessions by 32% over the five year study.  The authors suggest that perhaps this is a factor that contributes to the well-documented (and previously blogged) decline in physical activity seen in children as they go through adolescence.

The solution?  No one knows for sure but the McGill researchers recommend being especially mindful  to create opportunities for physical activity – outdoors or indoors – during winter months.  This may require more structured activities (i.e. sports leagues) and facilities.  It may also be where the DDR*, VCR**, or DVR*** may come in handy (see a previous post on video games).

A question still remains.  Would similar ebb and flow patterns of physical activity be seen in adolescents living in San Antonio or Tucson when heat is more of the problem than snow and rain?  If you live in a hot climate, tell us what you think.

*DDR – Dance Dance Revolution video game
**VCR – video cassette recorder
***DVR – digital video recorder

Belanger M, Gray-Donald K, O’Loughlin J, et al.  Influence of weather conditions and seasonality on physical activity in adolescents.  Annals of Epidemiology.  2009;19:180-186.