Introduction: A frequent co-morbid condition of chronic pain is profound physical deconditioning that results from inactivity. Objective assessment of physical conditioning in patients with chronic pain has been impeded by several factors that this study attempted to overcome. Of primary importance is verifying the efficacy of a physical reconditioning program. Further, decreases in pain, depression, and anxiety following treatment in a pain rehabilitation program have been well documented; however, no study has determined the immediate effects of brief exercise on these factors. The purposes of this study are a) to determine the effect of a 3 week aerobic training program on physical conditioning, and b) to assess the acute effects of a brief (10 minute) exercise protocol on pain, mood, and perceived exertion. Materials and Methods: A within group repeated measure analysis was used to compare data from an IRB approved data registry of 28 subjects capable of completing a treadmill protocol who were admitted to the Cleveland Clinic Chronic Pain Rehabilitation Program. Measures of heart rate, mood, pain, and perceived exertion were obtained. On average patients received 5 hours of conditioning per week, in addition to routine daily activities. Results: Results demonstrated significant short- and long-term benefits of exercise. Subjects showed a statistically significant reduction in exercise-induced cardiac acceleration from admission to 3 weeks. The brief exercise protocol also produced significant immediate antidepressant and anxiolytic effects. Perceived exertion also significantly decreased. Brief exercise was not found to have an acute analgesic effect. Conclusion: This research suggests that relatively modest exercise leads to improved mood and physical capacity, which has further implications for mortality risk. Further, it suggests that brief exercise is a safe, cost-free, nonpharmacologic strategy for immediately reducing depression and anxiety.