Objectives: To assess the effect of mild forced physical training on cognitive and locomotory behavior in old (26 mo.) mice. Design: Randomized, controlled study. Setting: Open-field in the behavioral laboratory. Participants: Sixteeen old sedentary male mice randomly assigned to one of two groups, exercise (E) or rest (R). Intervention: group E underwent treadmill running for one month at moderate intensity (belt speed = 8 m/min, 45 min, five days a week), group R was only allowed spontaneous locomotor activity. Measurements: exploratory and locomotor behavior were evaluated in an enriched environment (Ethovision recording). Results: motor patterns were significantly reduced (χ2 test, p