2016 年 5 巻 2 号 p. 195-203
Both aerobic exercise and resistance exercise are recommended to enhance health in elderly people. A hybrid training system (HTS), that provides resistance to the motion of a volitionally contracting agonist muscle by electrically stimulating its antagonist, was developed as a resistance exercise technique combining the benefits of electrical stimulation and volitional contractions. We then applied this concept to develop a novel training method using electrically stimulated eccentric contractions during aerobic walking exercise (HTSW). This study was designed to evaluate the effect of the new method on muscle strength and physical function by comparing it to unenhanced walking exercise. 16 subjects (2 male, 14 female; age average, 67.2 ± 2.6) were randomly divided into an HTSW group and a control group (CTR). They trained using either HTSW or unenhanced walking exercise (CTR) for 30 minutes three times a week for 12 weeks. Isokinetic knee extension/flexion torque, muscle volume (MV), a one-leg standing test, a functional reach test, 10-meter maximum gait speed, timed up & go test (TUG), and a 6-minute walking test were measured before and after the training period. We compared the differences between pre-training and post-training using the Wilcoxon signed rank test in each group. In the HTSW group, isokinetic knee extension (12%)/flexion torque (18%), MV (8%), 10-meter maximum gait speed (9%), TUG (26%), and 6-minute walking test (12%) significantly improved after the training period. In the CTR group, isokinetic knee flexion torque (15%), 10-meter maximum gait speed (9%), TUG (22%), and 6-minute walking test (16%) had significantly improved after the training period. HTSW may provide the benefits of both aerobic and resistance exercise.
