This commentary focuses on a complementary theoretical–experimental approach to the target article by Hill, Den Hartigh, Meijer, De Jonge, and Van Yperen (2018). In the target article, the authors develop an initial roadmap for identifying persistent behavioral patterns (i.e., athletic resilience) through measurements to identify specific attractor states and/or the attractor landscape. The goal of this approach is to promote a more complete understanding of the underlying attractor dynamics that give rise to resilient behavior. We extend the thesis of the target article via the concept of metastability. Metastable dynamics are the result of the system remaining poised on the edge of criticality. We argue that metastability is key for positively adapted behavior and, ultimately, successful athletic performance. When considered in this light, positive adaptations to adversity (i.e., resilience) are the minimum outcome, with performance enhancement in the face of adversity as the true performance goal. Such growth from adversity is termed antifragility. We next couch this concept in the context of evolutionary biology to leverage biological hormesis as a stress-response model for athletic performance. This allows for biology-inspired fitness profiles that provide a quantifiable measure of stress response relative to environmental change. From there, phenotypic plasticity can be calculated to further elucidate the relation between adversity and performance responses as a quantifiable index of antifragility. Finally, this approach is discussed in the context of personalized training interventions that facilitate the emergence of metastable dynamics that underlie phenotypic plasticity, with critical training windows introduced as opportunities to increase athletic antifragility. (PsycINFO Database Record (c) 2018 APA, all rights reserved)