Slow walking speed is highly prevalent among Veterans beginning in midlife. It is a major predictor of functional independence, independent of disease status and a predictor for subsequent hospitalization, disability and death. While rehabilitative care is the standard treatment for those with slow gait speed, the optimal mode of treatment is not yet identified. We have strong clinical support that a new model of physical therapy care known as Live Long Walk Strong (LLWS) may be an efficacious treatment for those screened with slow gait speed. LLWS is highly innovative, as it prioritizes unconventional treatment targets not typically addressed in standard care, including impairments in: 1) leg power; 2) trunk muscle endurance; 3) gait coordination (smoothness of walking); and 4) self-efficacy to engage in exercise. Through prior research, we identified that each of these four therapeutic targets are linked to mobility decline when impaired and that improvements in each alone can lead to mobility gains that surpasses standard care. No treatment targeting these attributes collectively is established, though LLWS is conceptually designed to do so. [Thus, we propose a phase II randomized controlled clinical trial (RCT) among Veterans 50 years and older to identify if LLWS care enhances these attributes and if by augmenting each, sustained improvements in gait speed result.] In a civilian-based clinical demonstration project, clinical proof of concept of LLWS was observed. LLWS targeted community-dwelling older adults. At the completion of LLWS care, we observed large improvements in mobility performance that exceeded clinically meaningful differences. These differences were observed even after accounting for health factors that may mitigate rehabilitative gains. [LLWS has great significance for the VA, because slow gait speed is prevalent in middle aged Veterans and improvements of the magnitude we observed are predictive lower health care costs and disability. However, while LLWS was clinically conceived to improve gait speed by enhancing each of these attributes, it is critical to know if two basic suppositions are true: 1) Are each of these four attributes improved by LLWS? and 2) Do these improvements induce immediate and sustained changes in gait speed among veterans beginning in midlife? Therefore, this study will establish efficacy and proof of concept of LLWS among Veterans beginning in midlife; an age-range largely ignored in prior clinical trials targeting gait speed.] LLWS has tremendous relevance for the VA. [For example, in our preliminary work among 174 Veteran primary care patients aged 50-98, >50% manifested a gait speed < 1.0 m/s, a speed indicating a heightened risk for adverse health outcomes.] Given Veteran’s higher levels of impairment compared to aged matched civilians, care should be as parsimonious and efficacious as possible. Thus, the major goal of this proposal is to establish LLWS as a non-invasive, new therapy targeting...