Ken Ishihara, MD, Satoshi Hirano, MD, DMSc, Eiichi Saitoh, MD, DMSc,
Shigeo Tanabe, RPT, PhD, Norihide Itoh, RPT, DMSc, Ryuzo Yanohara, RPT,
Tsubasa Katoh, RPT, Yuya Sawada, RPT, Tetsuya Tsunoda, MD, Hitoshi Kagaya, MD, DMSc
Jpn J Compr Rehabil Sci 6: 105-112, 2015
Objective: The balance exercise assist robot (BEAR)
is a balance training device that uses robotic technology.
The aim of this study was to clarify the
characteristics of leg muscle activity while using the
BEAR.
Methods: Subjects, comprising seven healthy adults,
played three types of games composed of center of
gravity movement tasks (tennis and skiing) and a
coping with disturbance task (rodeo). The games had
four levels of difficulty and each game was played for
90 seconds. Surface electromyography was used to
measure the gluteus maximal muscle, gluteus medius
muscle, rectus femoris muscle, vastus medialis muscle,
biceps femoris muscle, tibialis anterior muscle,
gastrocnemius and peroneus longus muscle on both
sides. Mean muscle activity was calculated from
muscle integrated electromyography.
Results: Muscle activity in each game increased with
the degree of difficulty. Comparison of muscle activity
between games indicated greater muscle activity in the
tibialis anterior muscle during rodeo than tennis
(p = .009) and skiing (p = .017). In the gastrocnemius,
muscle activity was greater during rodeo than during
skiing (p = .045) and in the peroneus longus muscle,
muscle activity was greater during skiing than tennis
(p = .041).
Conclusions: With the BEAR, the degree of difficulty
can be altered to adjust the load placed on the legs. The
three types of games each were able to promote
different types of leg activity.
Key words: robot, rehabilitation, balance exercise, degree of difficulty, electromyography