By Stacey Colino Just as developing strength and agility is crucial for physical fitness, the same is true for emotional fitness. In our culture, the strength part of the psychological equation is well understood, given that it’s often equated with having good coping skills and emotional resilience. But the perks of having emotional agility are not as widely appreciated. In her new book, Emotional Agility: Get Unstuck, Embrace Change, and Thrive in Work and Life (Avery, 2016), Susan David, PhD, a psychologist at Harvard Medical School and co-founder and co-director of the Institute of Coaching at McLean Hospital, defines emotional agility as “being flexible with your thoughts and feelings so that you can respond optimally to everyday situations.”