The 30-second rule gives people energy:Psychologist Henry H. Goddard concluded a study on energy levels in children using an instrument he called the “ergograph.” His findings are fascinating. He discovered that when tired children were given a word of praise or commendation, the ergograph showed an immediate upward surge of energy to children. When the children were criticized or discouraged, the ergograph showed that their physical energy took a sudden nosedive.
From John Maxwell's "25 Ways To Win With People"
