Constraint-induced movement therapy (CIMT) involves restricting use of an unaffected limb while intensively training an affected limb for several hours per day. It is based on research showing that restricting use of a monkey's unaffected forelimb led to improved use of the affected limb. Studies in humans found that restricting an unaffected arm along with task-specific training of the affected arm improved function of that arm. The EXCITE trial, a large randomized controlled trial, provided strong evidence of CIMT's efficacy for improving arm function after stroke. While very effective, the intensive nature of CIMT presents challenges to implementation in clinical settings. Modified versions have aimed to address these issues.