1. Keio University School of Medicine, Department of Sports Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan ; ;
2. Keio University School of Medicine, Department of Sports Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
3. Department of Neurology, Mitate Hospital, Fukuoka, Japan