Given that in NSW, this current week is Bicycle Week...

Health benefits of cycling, a summary of some recent studies on the health
and mental health benefits of cycling:

http://www.bv.com.au/Content/NavigationMenu/Cycling_Q_and_A/Fitness_and_Lifestyl\
e/hlthsum.pdf

More at http://uk.groups.yahoo.com/group/PhysicalActivityforMentalHealth

Kate:)