Effects of Physical Exercise on Cardiorespiratory Fitness and Cardiometabolic Outcomes in Schizophrenia Spectrum Disorders: The FitForLife National Intervention in Sweden

(1) Background: Individuals affected by schizophrenia spectrum disorders (SSDs) have an increased risk for cardiometabolic diseases. Improved cardiorespiratory fitness (CRF) is associated with lower cardiometabolic risk. The aim of the study was to analyze the effect of a six-month-long physical exercise intervention on CRF and cardiometabolic risk factors as well as whether the effect differed between sexes and different baseline CRF in SSD patients. (2) Methods: 122 patients at psychiatric open care units agreed to participate, 55 did not provide blood samples, and 14 dropped out, leaving 53 patients with complete pre-post data. BMI, waist-hip ratio, blood pressure, HbA1c, blood lipids, and CRF from ergometer bicycle tests were measured before and after the intervention. CRF was stratified into three groups. (3) Results: Cardiometabolic disturbances were common at baseline. After the intervention, all females and the group with the lowest CRF at baseline improved in triglyceride levels. The latter group also improved in CRF. (4) Conclusions: Females and those with the lowest baseline CRF had improved post-intervention, but causality cannot be inferred because our study was a non-randomized study without a control group.