Relationships between physical fitness, physical activity, smoking and metabolic and mental health parameters in people with schizophrenia

Low physical fitness has been recognised as a prominent behavioural risk factor for cardiovascular diseases (CVD) and metabolic syndrome (MetS), and as an independent risk factor for all-cause mortality. No studies have systematically assessed physical fitness compared with a matched health control group in patients with schizophrenia. Eighty patients with schizophrenia and 40 age-, gender- and body mass index (BMI)-matched healthy volunteers were included. All participants performed an Eurofit test battery and filled out the International Physical Activity Questionnaire. Patients additionally had a fasting metabolic laboratory screening and were assessed for psychiatric symptoms. Patients with schizophrenia demonstrated significant differences from controls in whole body balance, explosive leg muscle strength, abdominal muscular endurance, and running speed. Inactive patients scored worse on most Eurofit items than patients walking for at least 30 min per day. Low physical fitness was associated with illness duration, smoking, the presence of MetS and more severe negative, depressive and cognitive symptoms. Less physically active patients who smoke and suffer from high levels of negative, depressive and/or cognitive symptoms might benefit from specific rehabilitation interventions aimed at increasing physical fitness.