1. Department of Rehabilitation, Sanseikai Kitano Hospital, Sapporo, Hokkaido, Japan
2. Department of Rehabilitation, National Hospital Organization Hakodate Hospital, Hakodate, Japan
3. Cardiac Rehabilitation Center, Caress-Sapporo Hokko Memorial Hospital, Sapporo, Hokkaido, Japan
4. Department of Cardiovascular Medicine, National Hospital Organization Hakodate Hospital, Hakodate, Japan
5. Department of Orthopedics, Sapporo Kiyota Orthopedic Hospital, Sapporo, Hokkaido, Japan.