Warming up gently prepares your body for more strenuous working by mobilizing it and flushing fresh blood through your veins. I do not recommend stretching too much before working out. All this pulling on the tendons loosens their protective grip on the joints thus making your body more prone to injury. Stretching should definitely be done after working out to prevent a shortening of muscles and tendons.
But warming up like in my video below is not only a good idea before doing sport, investing three minutes for a warm up to start your day before you go to work will make you feel really awake and energized.
I hope to inspire you with my easy warm up video below, three minutes well used.
Get outside and move to your roots!