" Research backs up this “fake it till you feel it” strategy. One study found that when people assumed a high-power pose (for example, taking up space by spreading their limbs) for just two minutes, their dominance hormone levels (testosterone) went up and their stress hormone levels (cortisol) went down. As a result, they felt more powerful and in charge and showed a greater tolerance for risk. A simple change in posture led to a significant change in attitude.12 "

― Sheryl Sandberg , Lean In: Women, Work, and the Will to Lead