It is easy to assume that, because exercise is beneficial to one's health, more is better. Similarly, one may believe that the more intense one's positive personality traits are, the more effective leader he or she will be. Himelhoch and Raymond's book examines the influence of exercise habits and personality on leadership behaviors, using a curvilinear lens, and demonstrates a Goldilocks Paradox. Too much of a good thing can be a bad thing, and this research helps us understand what levels are best. Allan Afuah, PhD, Professor of Corporate Strategy and International Business, The Ross School of Business, The University of Michigan Understanding factors that contribute to effective leadership is important knowledge for developing and improving leaders. This thought-provoking work explores relationships between leisure exercise habits and leadership styles and considers some interesting hypotheses that are relevant across many fields. Beth A. Smith, PT, DPT, PhD, Assistant Professor of Research, Division of Biokinesiology and Physical Therapy, University of Southern California