The purpose of this study was to evaluate the change in dynamic and static balance ability during the menstrual cycle among young women. The subjects were young healthy women (n=12, age 20.4±1.2 years) with regular exercise and a normal menstrual cycle. The menstrual cycle was divided into 5 phases : Menstrual, Follicular, Ovulatory, Early luteal and Late luteal. Measurements were taken using the dynamic balance test, static balance test and looseness test. The dynamic balance test did not change during the menstrual cycle. Length Time within the static balance test increased in the late luteal phase compared to other menstrual cycle phases. The deviation of the mean of X within the static balance test increased in the follicular and late luteal phase and decreased in the ovulatory phase. Also, the deviation of the mean of X increased in the follicular phase compared to the menstrual phase and decreased in the menstrual and early luteal phases compared to the follicular and ovulatory. Left arm upper of laxity in hand on the back test within looseness test increased in the menstrual and early luteal phases compared to other menstrual cycle phases. These results suggest that static balance ability changes during the menstrual cycle.

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In order to study the effect of muscle exercise on the medical expenditure of the elderly, a three-year exercise program focusing on muscle activity was performed by an intervention group. Individual yearly medical expenditures were collected by 20 participants of the exercise group aver aging 65.2 years of age and 23 control subjects averaging 68.4 years of age with National Health Insurance coverage. Yearly medical expenditures for the exercise group were significantly lower than those of the control group at one and two years after entry. The expenditures increased by 62.6% from 1997 to 1999 in the control group, whereas they increased by only 16.8% for the exer cise group. The results suggest the possibility of the effectiveness of muscle exercise on the reduction in medical expenditure among the elderly.

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1.継続的に週3回以上レジスタンストレーニングを行っている被験者8名 (鍛錬者; TR群) ならびに座位業務に従事し, トレーニングを行っていない被験者6名 (非鍛錬者; UT群) を対象とし, 1分間の持続的なMVCを3セット行わせ, 課題遂行中の発揮トルク, TMSによるトルクおよび誘発筋電図の変化ならびにRMS/Fの変化を解析した.
2.発揮トルクの相対的な低下傾向は両群ともに類似しており, 課題終了時には約30%程度まで有意に低下した.また発揮トルクの低下とともにVAは低下し, 課題終了時にTR群で88.2%, UT群で77.3%に低下した.VAは2セット目以降でTR群の方がUT群よりも有意に高かった.
3.TR群のRMS/Fはセットの後半に大きく増加し, 2セット目以降でUT群よりも有意に高値を示した.
4.全てのセットにおけるSPの延長および1セット目のMEP面積の増加はUT群の方がTR群よりも有意に大きかった.
5.これらの結果から, 発揮トルクの低下に対して, UT群は中枢性疲労, TR群は末梢性疲労が大きな影響を与えていることが示唆された.また, 皮質運動野に対する抑制性入力が中枢性疲労の発現に大きな影響を与えており, トレーニングはこれらの機序を変化させる可能性が示唆された.

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The purpose of this study was to examine the effects of ankle plantar and dorsal flexion on the lower extremities' dynamics and crank torque in pedaling movements. Twelve males (6 cyclists and 6 non-cyclists) pedaled at the rate of 90 and 120 rpm for a power output of 200W. Subjects were divided into two groups according to the different ankle movement patterns in one crank rotation. The first group (Gr1) showed a one time plantar and dorsal flexion movement in one rotation. The second group (Gr2) showed two plantar and dorsal flexion movements in one rotation. It was assumed that the exertion of positive plantar flexor power in the upstroke phase could provide the difference of the ankle movement patterns. The following results were shown in Gr2 as compared with Grl. 1) The positive crank torque time ratio was extended due to dorsal flexor torque produced near the top dead center. 2) Continuous muscle contraction of the same muscle was avoided and reduction in a burden was brought about due to plantar flexion in the upstroke phase. 3) Reduction of hip extensor torque was shown. These results suggest that two dorsal and plantar flexion movements in one rotation in pedaling could be a more effective pattern in terms of muscle work.

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The purpose of this study was to investigate the differences and effects of positional loading (arm position change) and image loading in Budo (martial arts) competitors, mainly kendo (Japanese fencing) masters. The microcirculatory responses were measured by differential digital photoplethys-mography (ΔDPG) using the characteristics of Budo mental attitude, experience and skill as para-meters.
The subjects were 7 kendo masters of the fifth grade or higher with mean experience of 29 years, 7 kendo athletes, 7 kyudo (Japanese archery) athletes, 5 karate athletes in university sports clubs and 9 middle-aged controls. Positional loading induced myogenic responses and image loading for examining sympathetic effects via the central nervous system on peripheral circulation were mea-sured in the subjects at rest in a sitting position. The following results were obtained
The increase in the . ΔPG-P wave height in response to positional loading was markedly larger in the kendo masters. In particular, the increase when raising the right arm was significantly higher in the kendo masters than in the kyudo and karate athletes (P<0.05) . The decrease in the ΔDPG-P wave height when lowering the right arm was smallest in the kendo masters. There were differences in the peripheral vascular responses between kinds of Budo and levels of skill, which were induced by differences at the time of arm raising.
The DPG-P wave height was significantly lower during stress imaging than before loading in all subjects. The effect of stress imaging was smallest in the kendo masters, and markedly large in the kyudo athletes (P<0.05) . During relaxation imaging, an increase in the ΔDPG-P wave height was observed in the kendo masters alone, and the occurrence of vascular dilation was confirmed.
These results suggest that arteriolar responses of kendo masters are flexible and stable despite their long training period ; and the control and regulation of muscle vascular tone is well-maintained via the central nerve-sympathetic and myogenic coupling.

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To clarify the recovery patterns of spontaneous activity and liver damage after different stressors, female Fischer 344 rats were treated with Propionibacterium aches (P, aches) or water immersion stress before lipopolysaccharide (LPS) injection. They were then examined for wheel running activity, serum corticosterone concentration, serum alanine aminotransferase (ALT) activity, histological appearance of liver and plasma tumor necrosis factor alpha (TNF-a) concentration.
The recovery in physical activity of P. aches-treated rats was faster than that of water immersion rats. One day after the stressors, serum corticosterone cancentration and ALT activity of P. acnes-treated rats were higher than that of water immersion rats. In addition, increases in serum ALT activity and plasma TNF- a, as well as massive necrosis of the liver in P. acnes-treated rats were observed seven days after stress treatment. The P. acnes-LPS rats also showed a reduction in survival rate after 24 hours. These results suggest that P. acnes stress causes serious inflammation when stimulated by LPS. Although rapid recovery in physical activity was not inhibited by P. acnes stress, it differed from the response of water immersion stress.

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We carried out tests of visual functions and evaluated the effects of the correction of visual acuity on kinetic visual acuity (KVA) in 21 high school rugby players. KVA during sports activities was highly correlated with binocular vision (r=0.719, p<0.0001) and static visual acuity (SVA) (r =0.798, p<0.0001) . When binocular vision, SVA, and KVA during sports activities were compared after correction, they all significantly improved after correction (binocular vision: 0.78±0.39→1.46 ±0.26, p<0.0001 ; SVA : 0.86±0.48→1.31±0.25, p<0.01 ; KVA : 0.54±0.350.75±0.20, p <0.05) . Moreover, significant negative correlations were observed among binocular vision, SVA, and KVA and the percent improvement after correction (r=-0.755, r=-0.848, r=-0.829, respectively ; all p<0.001) . The percentage of KVA to SVA was 64.0±21.7% during sports activities and 59.1±16.7% after correction decreasing slightly with correction, though not significantly. Therefore, KVA, which plays an important role in sports activities, improved as SVA improved, and poor KVA is thought to improve to an adequate level by correction of visual acuity. However, the effect of a correction was smaller in KVA than in SVA, and KVA deteriorated with over-correction in some players. Further studies are needed concerning the criteria for correction to obtain good KVA and the relationship between correction and training.

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