This article is from the running Beginners' FAQ, by Ozzie Gontang with numerous contributions by others.
Some people run in their lunchbreaks, some in the evenings and some strange
souls claim to enjoy running in the early mornings. You have to find a
place in your life for running that you can stick to. If you do run in the
early mornings, pay special attention to warming up.
The climate and daylight can have an effect on when you run. High daytime
temperatures and humidity are a strong argument for running in the early
morning. Lunchtimes are good times to run when the temperatures are low and
the mornings and evenings dark.
 
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