1. Department of Health Sciences; University of Jyväskylä; Jyväskylä Finland
2. Department of Medical Rehabilitation; Oulu University Hospital and Institute of Health Sciences; University of Oulu; Oulu Finland
3. Central Hospital of Central Finland; Jyväskylä Finland
4. Department of Biomedical Engeneering; Dalian University of Technology; Dalian Liaoning China
5. Helsinki Sleep Clinic; Vitalmed Research Center; Helsinki Finland
6. Department of Sport and Physical Education; Shanghai Jiao Tong University; Shanghai China