This study aims to determine the effectiveness of a multicomponent exercise and therapeutic lifestyle (CERgAS) intervention at improving gait speed among older people in an urban poor setting in Malaysia. A total of 249 participants were divided into the intervention (n = 163) and control (n = 86) groups. The mean (SD) age of participants was 67.83 (6.37) and consisted of 88 (35.3%) males and 161 (64.7%) females. A generalized estimating equation with an intention-to-treat analysis was used to measure gait speed at four time points, baseline (T0), 6 weeks (T1), 3 months postintervention (T2), and 6 months postintervention (T3). The results showed significant changes for time between T0 and T3 (mean difference = 0.0882, p = .001), whereas no significant association were found for group (p = .650) and interaction (p = .348) effects. A 6-week intervention is inadequate to improve gait speed. Future efforts should introduce physical activity monitoring and increase exercise duration, frequency, and intensity.