744 Power of Smile

It would be fantastic if we do not fail to remember that smile is really a powerful action in life. As we all know, science studies has been telling us a lot about the tremendous positive effect of smiling. It's almost a miracle. And it's amazing that smile is such an easy action that can deliver the strongest and happiest emotion of all, but how difficult for us to keep remembering that simple fact. 

And I always wonder if smiling can be compatible with the most serious moment in life when you are in tense, really focused, and concentrated with highly sharpened sense inside and being under healthy pressure.  Can we smile under such situation, and what is the power of smile in such case? I'm really curious about it.