Seven men (mean age 60 years, range 44–73 years) within 6 months of their unilateral first-ever stroke participated in the study. All patients were admitted to the post-acute rehabilitation unit of Gifu Central Hospital or Tokai Memorial Hospital in Japan. Patients with severe cognitive impairment and those with cardiac pacemakers were not included in the study. The study protocol, which met the standards of the Declaration of Helsinki, was approved by the research ethics committees of Seijoh University (Approval Number 2016C0022), Gifu Central (Approval Number 133), and Tokai Memorial Hospital. Informed written consent was obtained from each participant before all procedures. All experiments were performed in a soundproof room in which the temperature was maintained at 24–26 °C.