Cognitive impairment is a major determinant of disability in schizophrenia. Aerobic exercise improves global cognition in schizophrenia, particularly working memory and attention/vigilance. Transcranial direct current stimulation (tDCS) targeting frontal regions has shown promise for cognitive deficits, including working memory improvements in some studies. This randomized 2×2 factorial trial will test the independent and combined effects of supervised aerobic exercise and prefrontal tDCS on cognition in treatment resistant schizophrenia, measured using the MATRICS Consensus Cognitive Battery (MCCB).