217 research outputs found
Effects of Mini Volley on Physical Fitness and Profile of Mood States in Middle-aged Women
本研究は,ミニバレーが中年女性の体力や気分に及ぼす効果を検討することを目的とした。被験者は,北海道在住でミニバレーチームに所属している中年女性20名と,コントロール群としてミニバレー群と同様の年齢,体格で,日常定期的な運動を行っていない女性20名の合計40名とした。介入期間は3ヶ月間とし,この前後に体力測定と気分調査を行った。体力の指標として握力,上体起こし,長座体前屈,反復横とび,1000m急歩,立ち幅跳びの6項目を実施した。また,全被験者に歩数計を装着してもらい,1週間の身体活動量を測定した。気分調査にはPOMSを用いた。その結果,身体活動量はミニバレー実施群が有意に大きい値を示した(p<0.05)。体力測定では,反復横とびと立ち幅跳びにおいて有意な交互作用が認められた。そのほかの項目には,有意な交互作用が認められなかった。そこで,1回目から2回目の変化量を検討した結果,1000m急歩において両群の間に有意な差が認められた。気分の調査では,POMSの活気,緊張-不安,抑うつ-落ち込みのそれぞれの尺度において,それぞれ有意な交互作用が認められた。ミニバレー実施群は活気が高くその他のネガティブな気分が低く表れていた。一方,非運動群は怒りと混乱の尺度以外は増加傾向にあり,活気尺度が減少していた。以上のことから,定期的な運動の継続的実施は下肢機能の維持・向上に有効であることが明らかになった。また,ミニバレーボールのようなレクリエーション的なスポーツは,気分を向上させ,ネガティブな気分を晴らすことが明らかになった
Dietary nitrate supplementation effect on dynamic cerebral autoregulation in normoxia and acute hypoxia
We tested the hypothesis that increasing the nitric oxide (NO) bioavailability by dietary nitrate would recover the hypoxia-induced reduction in dynamic cerebral autoregulation (CA). Twelve healthy males (age 21 ± 2 years) completed four days of dietary supplementation with a placebo or inorganic nitrate drink (140-ml beetroot juice per day) followed by 60-min of normoxia or hypoxia (fraction of inspired oxygen [FiO(2)] = 13%). Duplex ultrasonography was used to perform volumetric change-based assessment of dynamic CA in the internal carotid artery (ICA). Dynamic CA was assessed by rate of regulation (RoR) of vascular conductance using the thigh-cuff method. Four days of beetroot supplementation increased circulating nitrate by 208 [171,245] μM (mean difference [95% confidence interval]) compared with placebo. Dynamic CA was lower in hypoxia than normoxia (RoR Δ−0.085 [−0.116, −0.054]). Compared with placebo, nitrate did not alter dynamic CA in normoxia (RoR Δ−0.022 [−0.060, 0.016]) or hypoxia (RoR Δ0.017 [−0.019, 0.053]). Further, nitrate did not affect ICA vessel diameter, blood velocity or flow in either normoxia or hypoxia. Increased bioavailability of NO through dietary nitrate supplementation did not recover the hypoxia-induced reduction in dynamic CA. This suggests the mechanism of hypoxia-induced reduction in dynamic CA does not relate to the availability of NO
Five days of tart cherry supplementation improves exercise performance in normobaric hypoxia
Previous studies have shown tart cherry (TC) to improve exercise performance in normoxia. The effect of TC on hypoxic exercise performance is unknown. This study investigated the effects of 5 days of tart cherry (TC) or placebo (PL) supplementation on hypoxic exercise performance. Thirteen healthy participants completed an incremental cycle exercise test to exhaustion (TTE) under two conditions: (i) hypoxia (13% O2) with PL and (ii) hypoxia with TC (200 mg anthocyanin per day for 4 days and 100 mg on day 5). Pulmonary gas exchange variables, peripheral arterial oxygen saturation (SpO2), deoxygenated hemoglobin (HHb), and tissue oxygen saturation (StO2) assessed by near-infrared spectroscopy in the vastus lateralis muscle were measured at rest and during exercise. Urinary 8-hydro-2′ deoxyguanosine (8-OHdG) excretion was evaluated pre-exercise and 1 and 5 h post-exercise. The TTE after TC (940 ± 84 s, mean ± standard deviation) was longer than after PL (912 ± 63 s, p 2 and SpO2 were higher after TC than PL. Moreover, a significant interaction (supplements × time) in urinary 8-OHdG excretion was found (p 2 in the working muscles during submaximal exercise
Contact representation of short range correlation in light nuclei studied by the High-Momentum Antisymmetrized Molecular Dynamics
The high-momentum antisymmetrized molecular dynamics (HMAMD) is a new
promising framework with significant analytical simplicity and efficiency
inherited from its antisymmetrized molecular dynamics in describing the high
momentum correlations in various nuclear states. In the aim of further
improving the numerical efficiency for the description of nucleon-nucleon
correlation, we introduce a new formulation by including a new Gaussian
weighted basis of high momentum pairs in the HMAMD wave function, with which
very rapid convergence is obtained in numerical calculation. It is surprising
that the very high-momentum components in the new HMAMD basis are found to be
almost equivalent to the contact representation of the nucleon-nucleon pairs
with very small nucleon-nucleon distance. The explicit formulation for the
contact term significantly improves the numerical efficiency of the HMAMD
method, which shows the importance of the contact correlation in the
formulation of light nuclei
Measuring the Energy of Ventilation and Circulation during Human Walking using Induced Hypoxia
Energy expenditure (EE) during walking includes energy costs to move and support the body and for respiration and circulation. We measured EE during walking under three different oxygen concentrations. Eleven healthy, young, male lowlanders walked on a treadmill at seven gait speeds (0.67–1.83 m s−1) on a level gradient under normobaric normoxia (room air, 21% O2), moderate hypoxia (15% O2), and severe hypoxia (11% O2). By comparing the hypoxia-induced elevation in heart rate (HR [bpm]), ventilation (VE [L min−1]) with the change in energy expenditure (EE [W]) at each speed, we were able to determine circulatory and respiratory costs. In a multivariate model combining HR and VE, respiratory costs were 0.44 ± 0.15 W per each L min−1 increase in VE, and circulatory costs were 0.24 ± 0.05 W per each bpm increase in HR (model adjusted r2 = 0.97, p \u3c 0.001). These VE costs were substantially lower than previous studies that ignored the contribution of HR to cardiopulmonary work. Estimated HR costs were consistent with, although somewhat higher than, measures derived from catheterization studies. Cardiopulmonary costs accounted for 23% of resting EE, but less than 5% of net walking costs (i.e., with resting EE subtracted)
The Relationship between the Heat Disorder Incidence Rate and Heat Stress Indices at Yamanashi Prefecture in Japan
In recent years, the risk of heat disorder in daily life has increased dramatically because the thermal environment has been deteriorating. The main objective of this study was to examine regional differences in the relationship between heat disorder incidence rate and heat stress indices at Yamanashi Prefecture, Japan. Daily maximum air temperature and daily maximum WBGT were used as heat stress indices in each region. Nonlinear regression analysis was used to examine the regional difference in the relationship between the heat disorder incidence rate and heat stress indices in each region. The heat disorder incidence rate was correlated with both indices of heat stress in all regions. However, the more appropriate heat stress index for heat disorder prevention differed among regions. The distributions of heat stress indices, such as the slope of regression curve and the temperature threshold, differed in each region, irrespective of the index used. Therefore, the criteria for thermal conditions for heat disorder prevention need to be determined for each region, considering the regional characteristics of the relationship between the heat disorder incidence rate and heat stress indices
Variation of multi-Slater determinants in antisymmetrized molecular dynamics and its application to Be with various clustering
We propose a method to optimize the multi-Slater determinants of the
antisymmetrized molecular dynamics (AMD) in the linear combination form and
apply it to the neutron-rich Be nucleus. The individual Slater
determinants and their weights in the superposition are determined
simultaneously according to the variational principle of the energy of the
total wave function. The multi-AMD basis states of Be show various
cluster structures as well as the shell-model type. In the cluster
configurations, different intercluster distances are superposed automatically
indicating the role of the generator coordinates. We further introduce a
procedure to obtain the configurations for the excited states imposing the
orthogonal condition to the ground-state configurations. In the excited states
of Be, the linear-chain-like structure is confirmed consisting of
various clusters. The energy spectrum using the obtained basis states
reproduces the experiments. The present framework can be the method to find the
optimal multi-configuration for nuclear ground and excited states.Comment: 13 pages, 8 figure
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