Clinical Study Effects of Gait Self-Efficacy and Lower-Extremity Physical Function on Dual-Task Performance in Older Adults Diane K. Ehlers, 1 Sarah E. Banducci, 1 Ana M. Daugherty, 1 Jason Fanning, 2 Elizabeth A. Awick, 1 Gwenndolyn C. Porter, 3 Agnieszka Burzynska, 4 Sa Shen, 1 Arthur F. Kramer, 5 and Edward McAuley 1 1 University of Illinois at Urbana-Champaign, Urbana, IL, USA 2 Wake Forest University, Winston-Salem, NC, USA 3 University of Nebraska Medical Center, Omaha, NE, USA 4 Colorado State University, Fort Collins, CO, USA 5 Northeastern University, Boston, MA, USA Correspondence should be addressed to Diane K. Ehlers; dkehlers@illinois.edu Received 29 June 2016; Revised 9 December 2016; Accepted 10 January 2017; Published 1 February 2017 Academic Editor: Erwin van Wegen Copyright © 2017 Diane K. Ehlers et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objectives. Despite evidence of self-efcacy and physical function’s infuences on functional limitations in older adults, few studies have examined relationships in the context of complex, real-world tasks. Te present study tested the roles of self-efcacy and physical function in predicting older adults’ street-crossing performance in single- and dual-task simulations. Methods. Lower- extremity physical function, gait self-efcacy, and street-crossing success ratio were assessed in 195 older adults (60–79 years old) at baseline of a randomized exercise trial. During the street-crossing task, participants walked on a self-propelled treadmill in a virtual reality environment. Participants crossed the street without distraction (single-task trials) and conversed on a cell phone (dual-task trials). Structural equation modeling was used to test hypothesized associations independent of demographic and clinical covariates. Results. Street-crossing performance was better on single-task trials when compared with dual-task trials. Direct efects of self-efcacy and physical function on success ratio were observed in dual-task trials only. Te total efect of self-efcacy was signifcant in both conditions. Te indirect path through physical function was evident in the dual-task condition only. Conclusion. Physical function can predict older adults’ performance on high fdelity simulations of complex, real-world tasks. Perceptions of function (i.e., self-efcacy) may play an even greater role. Te trial is registered with United States National Institutes of Health ClinicalTrials.gov (ID: NCT01472744; Fit & Active Seniors Trial). 1. Introduction Adults aged 65 years and older represent 8% of the population worldwide and are expected to comprise 16% by 2050. Rapid increases in the number of older adults by more than 250% are expected in many countries, driving the older adult population to nearly 1.5 billion worldwide [1]. Unfortunately, approximately 41% of older adults report at least one functional limitation related to activities of daily living, with 30% of older women and 19% of older men unable to perform one or more of the following physical functions: stooping or kneeling, reaching overhead, writing/grasping small objects, walking two to three blocks, or lifing ten pounds [2]. It is well-known these age-related declines in function can have signifcant implications for independence, quality of life, and safety [3, 4], in addition to increased risk of disability, morbidity, and mortality [5]. A strong body of evidence indicates that impaired phys- ical function performance and self-efcacy may lead to an increase in perceived functional limitations [6–12] and subse- quent disability [5]. Self-efcacy is a cognitive control system and refers to individuals’ beliefs in their ability to carry out a specifc course of action, particularly in challenging con- ditions [13]. As such, perceptions of capabilities, in addition to actual physical ability, are strongly related to individuals’ actions [11, 14, 15]. In both cross-sectional and longitudinal Hindawi BioMed Research International Volume 2017, Article ID 8570960, 10 pages https://doi.org/10.1155/2017/8570960