This study examined design requirements for female boomer activewear for indoor fitness through a sequential exploratory mixed methods research. The method consists of three phases: (a) face-to-face in-depth interviews (N=15) were used to identify and define design attributes of activewear using MaxQDA, (b) 3D virtual prototypes were generated for online survey stimuli, and (c) an online survey (N=321) was used to examine how consumers evaluated and perceived the activewear for female boomers. Based on the findings, this study proposed design prototypes and a conceptual model that illustrates the interrelationships of factors influencing design requirements for female boomer activewear including aging factors, functional, expressive, and aesthetic (FEA) dimensions and wearing intention. The study validates the efficacy of the extended FEA model and has practical implications for retailers on product development and commercialization strategies for female boomer consumers.