The object is to develop a training system of simultaneous walking and cognitive training for improving cognitive function of people with schizophrenia. The training program, called "Simultaneous Walk And Think for Cognitive Health mobile application software"(SWATCH App), is developed by researchers. A randomized controlled trial will be carried out to test the effectiveness of the training system. Ninety participants will be randomly assigned to: simultaneous training of walking and cognitive group, the cognitive training group, and treatment as usual group. The intervention for those groups will lasts for 12 weeks, with a 12 week of followup. The measurements include the cognitive function, physical fitness, and quality of life.

Background: Schizophrenia is one of the severe mental disorders. In addition to psychiatric symptoms, cognitive impairment is a key clinical feature in this population, which significantly negatively influences their functional performance and independence. While the cognitive remediation therapy demonstrates positive results, it often involves specialized and expensive computerized cognitive training system, which limits its application in clinical setting. More evidence is available to support the benefits of exercise training on cognitive functions of schizophrenia. Combination of exercise and cognitive training is a promising program and can improve cognitive functions of the elderly. However, this combined therapy is still limited to schizophrenia. Simultaneous training of walking and cognitive tasks via auditory mobile application is an innovative program for saving cost, time, and manpower. Further study is needed to develop the simultaneous training program and to examine the effectiveness.

Purposes: To examine the effects of the training program on cognitive functions, fitness, functional performance and quality of life.

Methods: A 3-arm, single-blinded, randomized controlled trial is used to recruit 90 participants and then randomly allocated to the simultaneous training group, the cognitive training group, and the treatment as usual group. The first two training groups receive training for 30-40 minutes, 3 times a week for 12 weeks, as well as a follow-up of 12 weeks. All participants will be assessed at baseline, post-test and follow-up assessment. Primary outcome is cognitive function and secondary outcomes are fitness, functional performance, and quality of life.

Contribution: The study can be used as an evidence-based program to improve cognitive functioning of people with schizophrenia. With the development of mobile App and the use of fitness wearable device, the training program enables people with schizophrenia to walk and practice cognitive training simultaneously in a group format. It will help clinical professionals be able to serve the increasing number of people with severe mental illness with less manpower and specialized equipment. The study is also helpful to better understanding the isolated role of aerobic exercise in the dual-task training, and to apply to other groups, like the elderly or dementia.

Inclusion Criteria:

1. Diagnosis of schizophrenia or schizoaffective disorder by a psychiatric clinician on the basis of the criteria set the Diagnostic and Statistical Manual of Mental Disorders 5th edition, DSM-5, has been more than 1 year.
2. Age 20-60 years old.
3. Living in daycare center or community-based mental health rehabilitation services or rehabilitation ward.
4. Having stable psychiatric conditions (i.e., primary psychiatric medications had not changed for more than two months)
5. The MATRICS Consensus Cognitive Battery (MCCB) (Nuechterlein et al., 2008) shows that at least one domain with cognitive impairment (below the value of -1SD).
6. Can follow the research process and sign the consent form.

Exclusion Criteria:

1. Traumatic brain injury and other neurological diseases, alcohol and substance abuse
2. Pregnancy, cardiovascular disease, and unsuitable to exercise training due to physical movement difficulties
3. According participants' self-report, having following conditions, including severe heart failure, myocardial infarction, angina pectoris, chronic obstructive pulmonary disease, COPD, poor glycemic control (i.e., dialysis, diabetic neuropathy or retinopathy) and lower extremity arthritis
4. Uncontrolled hypertension with SBP> 160 mmHg or DBP> 110 mmHg
5. Diagnosis of intellectual disability
6. Unconscious or confusion of consciousness
7. Participating in other intervention studies