We investigated health promotion effects of walking exercise on a sandy beach and in a forest for 40 days for healthy adults aged 53-69 years. At first, 10 subjects walked sandy beach, forest road, and concrete road (control), each 300-m long, and calorie consumptions were measured to determine the characteristics of each walking course. In walking exercise, 18 subjects walked about 2.3-km course, which consisted of a sandy beach and a forest road, for 30 minutes per a day. Before and after the walking exercise for 40 days, various physiological parameters were measured. Calorie consumption in the 300-m walk was significantly higher for sandy beach (18.9 ± 3.6 kcal) and forest road (19.5 ± 4.0 kcal) than concrete road (15.3 ± 3.3 kcal). Calorie consumption in a walking exercise was about 120 kcal. After the 40-days exercise, the following significant changes were found: decrease in body fat ratio, restoration of resting systolic blood pressure to a safe range, increase in muscle strength of plantar flexor and knee extensor, and improvement of equilibrium function and aerobic work capacity. These results evidenced health promotion effects of walking exercise on a sandy beach and in a forest.
The present study applied transcranial magnetic stimulation to the motor area of the first dorsal interosseous muscles in the right side, and investigated sports experience effect on changes in motor evoked potentials (MEP) of the first dorsal interosseous muscles while maintaining neck flexion position. Subjects were classified into two groups: sports experience group that has belonged to sports club (SE group, n = 10) and sports inexperience group that has never belonged to any sports club (SI group, n = 15). MEP was measured with the chin resting on a stand (chin-on condition) and with voluntary maintenance of neck flexion (chin-off condition) at 80% maximal neck flexion angle. In SE group, MEP latency shortened 0.27 ± 0.35 ms and amplitude of MEP increased 60.9 ± 43.0% in the chin-off, compared with the chin-on condition. On the other hand, in SI group, no significant difference in latency and amplitude of MEP was found between postural conditions. Sports experience will be effective on changes in MEP of the first dorsal interosseous muscles while maintaining neck flexion position. These results suggested that the brain activation with maintaining the neck flexion position enhanced the excitability in the motor area of the first dorsal interosseous muscles, and that the brain activation to the motor area of the first dorsal interosseous was formed through sports experience.
We investigated the developmental changes in postural movement patterns during bilateral arm flexion in children. A total of 174 subjects participated in this study from 4 to 12 years old. In response to a visual stimulus presented at 2-4 s after a warning signal, the subjects initiated the bilateral arm flexion as quickly as possible and then stopped their arms voluntarily at a horizontal position. After 5 practice trials, 10 test trials were performed. Movement angles of the trunk and leg joints during the arm flexion were analyzed, based on the small reflective markers placed over the following positions: head of the fifth metatarsal, external malleolus, knee, trochanter major, and vertebra prominence. Young children mainly extended the trunk rather than the ankle during the arm movement, while older children leaned the whole body backward. The postural movement patterns were categorized on the basis of the movement angle of the foot-leg and leg-trunk into the following three patterns: hip extension (HE), hip flexion (HF), and backward leaning (BL) types. More than half of children aged 4-6 years were categorized as HE. BL gradually increased from aged 7-8 years and older. The percentage distribution of each type at aged 11-12 years differed with younger children. The percentage of HF and BL were significantly larger than HE. These results suggested that the postural movement pattern during bilateral arm flexion would change with age.