Simonsick EM, et al. - The authors performed this study to assess the potential contribution of severity of lumbopelvic pain (LPP) in well-functioning older adults to poorer walking efficiency, lack of endurance, slower gait speed, and decline in these mobility parameters over 1 to 5 years. In well-functioning older adults, they recognized a common occurrence of LPP. This was associated with greater energetic cost of walking and poorer perceived and observed walking endurance.