Muscle damage indicated by maximal voluntary contraction strength changes from immediately to 1 day after eccentric exercise of the knee extensors

The present study examined if the magnitude of changes in indirect muscle damage markers could be predicted by maximal voluntary isometric contraction (MVIC) torque changes from immediately to 1 day after eccentric exercise. Twenty-eight young men performed 100 maximal isokinetic (60°/s) eccentric contractions of the knee extensors. MVIC torque, potentiated doublet torque, voluntary activation (VA) during MVIC, shear modulus of rectus femoris (RF), vastus medialis and lateralis, and muscle soreness of these muscles were measured before, immediately after, and 1–3 days post-exercise. Based on the recovery rate of the MVIC torque from immediately to 1-day post-exercise, the participants were placed to a recovery group that showed an increase in the MVIC torque (11.3–79.9%, n = 15) or a no-recovery group that showed no recovery (−71.9 to 0%, n = 13). No significant difference in MVIC torque decrease immediately post-exercise was found between the recovery (−33 ± 12%) and no-recovery (−32 ± 9%) groups. At 1–3 days, changes in MVIC torque (−40 to −26% vs. −22 to −12%), potentiated doublet torque (−37 to −22% vs. −20 to −9%), and proximal RF shear modulus (29–34% vs. 8–15%) were greater (p \u3c 0.05) for the no-recovery than recovery group. No significant group differences were found for muscle soreness. The recovery rate of MVIC torque was correlated (p \u3c 0.05) with the change in MVIC torque from baseline to 2 (r = 0.624) or 3 days post-exercise (r = 0.526), or peak change in potentiated doublet torque at 1–3 days post-exercise from baseline (r = 0.691), but not correlated with the changes in other dependent variables. These results suggest that the recovery rate of MVIC torque predicts changes in neuromuscular function but not muscle soreness and stiffness following eccentric exercise of the knee extensors

Relation of leg phase angle from bioelectrical impedance analysis with voluntary and evoked contractile properties of the plantar flexors

Introduction: Bioelectrical impedance analysis (BIA) can noninvasively and quickly assess electrical properties of the body, such as the phase angle. Phase angle is regarded as the quantity and/or quality of skeletal muscle and is associated with exercise performance, such as jump height and walking speed. Although the phase angle derived from BIA is assumed to be a useful way to assess muscle function, the relationship between the phase angle and neuromuscular properties has not been fully investigated. The purpose of this study was to investigate the association of phase angle with voluntary and evoked contractile properties in 60 adults (age, 21–83 years; 30 females and 30 males).Methods: The phase angle of the right leg at 50 kHz was evaluated using BIA. The twitch contractile properties (peak twitch torque [PTtwitch], rate of twitch torque development [RTDtwitch], and time-to-PTtwitch [TPTtwitch]) of the plantar flexors were measured using tibial nerve electrical stimulation. Maximal voluntary isometric contractions (MVICs) were performed to measure the maximal muscle strength and explosive muscle strength, from which the peak MVIC torque (PTMVIC) and rate of torque development (RTD) over a time interval of 0–200 ms were assessed, respectively. The root mean square (RMS) values of electromyographic (EMG) activity during the PTMVIC and RTD measurements (EMG-RMSMVIC and EMG-RMSRTD, respectively) were calculated. The RTD and EMG-RMSRTD were normalized using PTMVIC and EMG-RMSMVIC, respectively.Results and discussion: Phase angle significantly correlated with twitch contractile properties (|r| ≥ 0.444, p < 0.001), PTMVIC (r = 0.532, p < 0.001), and RTD (r = 0.514, p < 0.001), but not with normalized RTD (r = 0.242, p = 0.065) or normalized EMG-RMSRTD (r = −0.055, p = 0.676). When comparing measurement variables between the low- and high-phase angle groups while controlling for sex and age effects, the high-phase angle group showed greater PTtwitch, RTDtwitch, PTMVIC, and RTD (p < 0.001) and shorter TPTtwitch (p < 0.001) but not normalized RTD (p = 0.184) or normalized EMG-RMSRTD (p = 0.317). These results suggest that the leg phase angle can be an indicator of voluntary and evoked muscle contractile properties but not the neuromuscular activity of the plantar flexors, irrespective of sex and age

ピオグリタゾン トウヨ ニヨル フクブ ダイドウミャクリュウ ニオケル コウドウミャク コウカ サヨウ

Accumulating evidence suggests that inflammatory cytokines secreted from visceral fat tissues potentially promote atherosclerosis progression. Recent reports suggested that pioglitazone, which is an anti-diabetes drug, reduces expression of tumor necrosis factor（TNF）‐α and ameliorates insulin-resistance in diabetic mice. Pioglitazone was also reported to suppress progression of coronary atherosclerosis. The objective of this study is to assess the effect of pioglitazone on inflammatory changes in abdominal aortic aneurysms（AAAs）. This study protocol was approved by the medical ethics committee in Tokushima University Hospital. Patients with AAA were randomized into two groups. One was with pioglitazone（Group P）. The other was without pioglitazone（Group C）. Biopsy specimens were obtained from the abdominal subcutaneous fat, the greater omentum, the retroperitoneal periaortic fat and the aneurysmal wall. Immunohistochemistry of CD ６８in those specimens was performed. The number of macrophages in Group P was lower than that in Group C. Expressions of inflammatory cytokines in those specimens were evaluated by real-time quantitative reverse transcription-polymerase chain reaction analysis. Expression of inflammatory cytokines in Group P were reduced, when compaird with those in Group C. Our data may suggest that pioglitazone reduce inflammatory changes in human aortic aneurysm

The Examination of the Use Possibility of the Way that a Self-Portrait Meeting : Interview：3 Case Studies of the School Refusal

本研究では，生徒が描いた自画像の顔の部位に視点を当てた自画像対面法における構造化されたPDI によって，生徒が自画像全体から感じること，そして，目，眉，髪の毛，耳の各部位の左右においては，好きな部位があることが示された。そして，生徒は各々の部位の好きな部位からはポジティブ感情をイメージし，もう一方（好きではない）の部位からはネガティブ感情をイメージすることが示され，生徒自身の自己理解を深めることにつながっていることが伺えた。特にネガティブ感情をイメージする部位においては，不登校の原因等と関連している可能性があることが明らかになった