Several studies have focused on detection of simulated injury or submaximal effort using forced-choice measures of memory. However, few studies have examined the role of motor performance in patient effort, and no studies have examined motor functioning in an injury simulation. In this study, we administered measures of motor strength, motor speed, and attention and a forced-choice memory measure to 30 participants instructed to simulate brain injury and 30 participants instructed to perform to the best of their abilities. Simulators' level of performance and variability were significantly different from those of participants instructed to give maximal performance. Variables derived from motor measures may serve as useful supplemental indicators of incomplete effort.