Background: The purpose of this study was to examine functional capacity of cardio-respiratory system in patients with schizophrenia, and to evaluate the effects of 12 weeks prescribed physical activity on aerobic capacity and symptoms of schizophrenia.
Subjects and methods: Study involved 80 hospitalized patients with any of the subtypes of schizophrenia (42 men, 38 women). They were divided into two groups: exercise and control group, both with 40 patients. Maximal aerobic capacity (VO2 max) as an indicator of cardiovascular fitness has been obtained by cardiopulmonary stress test on a treadmill. Twelve weeks program of prescribed physical activity (45 minutes, four times per week) was made for every patient individually. Patients in exercise group practiced in training zone between 65 and 75% of their maximum heart rate (HR). Target HR was controlled by Polar F4 monitors. Symptoms of schizophrenia were measured by using Positive and Negative Symptoms Scale (PANSS).
Results: Before the exercise program was introduced, measured VO2 max was significantly lower in patients with schizophrenia, than the expected average value in matched healthy subjects (p<0.001). After twelve weeks, patients in exercise group showed a significant increase of VO2max (p=0.002), and significantly higher level of VO2max compared to the control group (p=0.000). Significant differences were also observed on PANSS general psychopathology subscale (p=0.007) and on PANSS total score (p=0.001). The pharmacotherapy and exercise had influence on PANSS general psychopathology (p=0.002) and PANSS total score (p=0.001).
Conclusions: Individuals with schizophrenia have lower levels of aerobic capacity compared to general population. Prescribed physical activity significantly improves aerobic capacity in people with schizophrenia and it is effective in amelioration of some psychiatric symptoms. Prescribed physical activity could be an effective adjunctive treatment for patients with schizophrenia, not only for prevention and treatment of comorbidities, but also having an impact on symptoms of schizophrenia.