TL:DR: adding ~150 minutes workouts per week (at 60-80% max heart rate, in 4 sessions of about 40 minutes a week over 6 months) to Brain HQ and SocialVille online cognitive training improved results significantly.
In a randomized controlled trial with 47 first-episode patients with schizophrenia, we contrasted six months of Cognitive Training & Exercise (CT&E) with Cognitive Training (CT) alone. The computerized cognitive training using PositScience BrainHQ and SocialVille programs was provided to all participants, four hours/week at the UCLA clinic for six months. The CT&E group also participated in total body circuit training exercises, with a goal of completing 150 minutes/week.
Both groups showed cognitive and work/school functioning gains, but the improvements were three times as large when aerobic exercise was added to cognitive training.