In the design of artifacts that interact with people, the spatial dimensions of the user population are often used to size and engineer the artifact. The variability in anthropometry indicates the fixed allocation of space, adjustability requirements, or how many sizes are needed to accommodate the intended user population. Various tools are used to achieve this goal, including boundary manikins, digital human models, prototypes and population models, and hybrid methods that combine the approaches. The present work explores each of these and their relative strengths and weaknesses. This is done in the context of a univariate case study involving the adjustability requirements of a stationary bicycle. An experiment involving 51 individuals was conducted to obtain the data necessary for utilizing and evaluating the methods.