Patients suffering from schizophrenia have an illness-related vulnerability to adopt deleterious lifestyles in addition to a congestion of cardiovascularand metabolic risk factors from antipsychotics and a vulnerability for developing cardiovascular disease (CVD). The combination of these factors causes impaired physical fitness, weight gain, obesity, hyperglycemia, type 2 diabetes, hyperlipidemia and ultimately increased risk of CVD. Although these risk factors are related to the physical fitness level and are improvable with aerobic endurance training, there has not been much attention to the contribution of poor physical fitness to the riskof CVD in schizophrenia. Reduced physical fitness also compromises the ability to perform lifestyle physical activity that is necessary for social rehabilitation and integration into the community.
High aerobic intensity training (HIT) improve maximal oxygen uptake (VO2max), mechanical efficiency of walking and risk factors for CVD but has not been investigated in patients with schizophrenia. A major concern over the cardiovascular health in people with schizophrenia is their ability to engage in and participate in physical training. In addition, inherent difficulties in recruitment to randomized controlled trials and distrust in methodological issues has been described.
25 inpatients were allocated to either HIT or playing computer games (control), 3 days per week for 8 weeks. HIT consisted of 4 x 4-min intervals with 3-min break periods, at 85–95% and 70% of peak heart rate,respectively. The HIT group improved both VO2max and mechanical efficiency of walking by 12%, however there were no changes in the control group.
Conclusion: This study indicates that patients with schizophrenia have a level of VO2max that is associated with increased risk of CVD. The patients also seem to have poor net mechanical efficiency of walking and spend excessive energy during walking. HIT can effectively improve VO2max and mechanical efficiency of walking during 8 weeks in patients that adhere to training. Treatment for schizophrenia should include efficient aerobic endurance training to contribute risk reduction of inactivity-related comorbidity and poor physical ability.