Effects of high aerobic intensity training in patients with schizophrenia—A controlled trial

Background: Patients with schizophrenia have a high risk of cardiovascular disease (CVD). High aerobic intensity training (HIT) improve peak oxygen uptake (VO(2peak)), net mechanical efficiency of walking and risk factors for CVD but has not been investigated in patients with schizophrenia. Aims: To investigate effects from HIT on VO(2peak), net mechanical efficiency of walking and risk factors for CVD in patients with schizophrenia. Methods: 25 inpatients (F20-29, ICD-10) were allocated to either HIT or playing computer games (CG), 3 days per week for 8 weeks. HIT consisted of 4 × 4-min intervals with 3-min break periods, at 85-95% and 70% of peak heart rate, respectively. Results: 12 and seven patients completed HIT and CG, respectively. The baseline VO(2peak) in both groups combined (n = 19) was 36.8 ± 8.2 ml/kg/min and 3.12 ± 0.55 1/min. The HIT group improved VO(2peak) by 12% from 3.17 ± 0.59 to 3.56 ± 0.68 1/min (P < 0.001), more than the CG group (P = 0.014). Net mechanical efficiency of walking improved by 12% in the HIT group from 19.8 ± 3.0% to 22.2 ± 4.5% (P = 0.005), more than the CG group (P = 0.031). The psychiatric symptoms, expressed as the Positive and Negative Syndrome Scale (PANSS) and the Calgary Depression Scale for Schizophrenia (CDSS), did not improve in either group. Conclusions: VO(2peak) and net mechanical efficiency of walking improved significantly by 8 weeks of HIT. HIT should be included in rehabilitation in order to improve physical capacity and contribute risk reduction of CVD.