Acute and Prolonged Effects of 300 sec of Static, Dynamic, and Combined Stretching on Flexibility and Muscle Force.

Static stretching (SS), dynamic stretching (DS), and combined stretching (CS; i.e., DS+SS) are commonly performed as warm-up exercises. However, the stretching method with the greatest effect on flexibility and performance remains unclear. This randomized crossover trial examined acute and prolonged effects of SS, DS, and CS on range of motion (ROM), peak passive torque (PPT), passive stiffness, and isometric and concentric muscle forces. Twenty healthy young men performed 300 sec of active SS, DS, or CS (150-sec SS followed by 150-sec DS and 150-sec DS followed by 150-sec SS) of the right knee flexors on four separate days, in random order. Subsequently, we measured ROM, PPT, and passive stiffness during passive knee extension. We also measured maximum voluntary isometric and concentric knee flexion forces and surface electromyographic activities during force measurements immediately before, immediately after, and 20 and 60 min after stretching. All stretching methods significantly increased ROM and PPT, while significantly decreasing isometric knee flexion force (all p < 0.05). These changes lasted 60 min after all stretching methods; the increases in ROM and PPT and the decreases in isometric muscle force were similar. All stretching methods also significantly decreased passive stiffness immediately after stretching (all p < 0.05). Decreases in passive stiffness tended to be longer after CS than after SS or DS. Concentric muscle force was decreased after SS and CS (all p < 0.05). On the other hand, concentric muscle force was unchanged after DS, while the decreases in surface electromyographic activities during concentric force measurements after all stretching methods were similar. Our results suggest that 300 sec of SS, DS, and CS have different acute and prolonged effects on flexibility and muscle force.

Construction of brain area risk map for decision making using surgical navigation and motor evoked potential monitoring information.

PURPOSE: Surgical devices or systems typically operate in a stand-alone manner, making it difficult to perform integration analysis of both intraoperative anatomical and functional information. To address this issue, the intraoperative information integration system OPeLiNK® was developed. The objective of this study is to generate information for decision making using surgical navigation and intraoperative monitoring information accumulated in the OPeLiNK® database and to analyze its utility. METHODS: We accumulated intraoperative information from 27 brain tumor patients who underwent resection surgery. First, the risk rank for postoperative paralysis was set according to the attenuation rate and amplitude width of the motor evoked potential (MEP). Then, the MEP and navigation log data were combined and plotted on an intraoperative magnetic resonance image of the individual brain. Finally, statistical parametric mapping (SPM) transformation was performed to generate a standard brain risk map of postoperative paralysis. Additionally, we determined the anatomical high-risk areas using atlases and analyzed the relationship with each set risk rank. RESULTS: The average distance between the navigation log corresponding to each MEP risk rank and the anatomical high-risk area differed significantly between the with postoperatively paralyzed and without postoperatively paralyzed groups, except for "safe." Furthermore, no excessive deformation was observed resulting from SPM conversion to create the standard brain risk map. There were cases in which no postoperative paralysis occurred even when MEP decreased intraoperatively, and vice versa. CONCLUSION: The time synchronization reliability of the study data is very high. Therefore, our created risk map can be reported as being functional at indicating the risk areas. Our results suggest that the statistical risks of postoperative complications can be presented for each area where brain surgery is to be performed. In the future, it will be possible to provide surgical navigation with intraoperative support that reflects the risk maps created.

Effects of High-Intensity Stretch with Moderate Pain and Maximal Intensity Stretch without Pain on Flexibility.

In this study, we aimed to identify the time course effects of different intensities of static stretch (SST) (maximal intensity without pain vs. high-intensity with moderate pain) on flexibility. This study included 16 healthy students (8 men and 8 women) who performed 1) 5-minute SST at 100%, 2) 110%, and 3) 120% intensity, as well as 4) no stretching (control) in a random sequence on four separate days. Static passive torque (SPT), hamstring electromyography (EMG), and pain intensity were continuously recorded during SST. We assessed markers of stiffness, range of motion (ROM), and maximal dynamic passive torque (DPTmax) before SST and 0, 15, 30, 45, 60, 75, and 90 minutes after SST. Stiffness decreased and ROM and DPTmax increased significantly immediately after SST at the three different intensity levels (p < 0.05). The effects of SST at 120% intensity were stronger and lasted longer than the effects of SST at 110% and 100% intensity (stiffness: -17%, -9%, and -7%, respectively; ROM: 14%, 10%, and 6%, respectively; DPTmax: 15%, 15%, and 9%, respectively). SPT decreased after SST at all intensities (p < 0.05). SST at 120% intensity caused a significantly greater reduction in SPT than SST at 100% intensity (p < 0.05). Pain intensity and EMG activity increased immediately after the onset of SST at 120% intensity (p < 0.05), although these responses were attenuated over time. Stretching intensity significantly correlated with the degree of change in ROM and stiffness (p < 0.05). These results support our hypothesis that stretch-induced flexibility is amplified and prolonged with an increase in stretch intensity beyond the pain threshold. Additional studies with more participants and different demographics are necessary to examine the generalizability of these findings.

The effect of simulated gestational weight gain on balance, gait, and fear of falling.

The effects of pregnancy on balance with the eyes closed and maximum walking speed remain unclarified. The present study aimed to examine the effect of simulated gestational weight gain on balance, gait, and fear of falling in nulligravid women to enhance understanding of the impact of gestational weight gain. We prospectively evaluated the following outcomes in 24 healthy nulligravid women with and without a maternity-simulation jacket that simulated third-trimester pregnancy. To measure balance, we used the single-leg-stance test with eyes open and closed, and the functional reach test. We evaluated gait function by measuring walking speed, step length, and cadence at self-selected and maximum speeds. We used the timed-up-and-go test as a comprehensive measure of gait and balance, and the modified falls efficacy scale to evaluate fear of falling. Differences in these parameters between a simulated gestational weight gain condition and a "nonpregnant" condition were assessed. Simulated gestational weight gain caused significantly worse performances in the single-leg-stance test with eyes open and closed, functional reach test, walking speed, step length at self-selected and maximum speeds, and timed-up-and-go test. The effect size was larger for the single-leg-stance test with eyes closed than with eyes open. The average score for each modified falls efficacy scale item ranged from 4.7-8.5. In conclusion, balance decreased with simulated gestational weight gain, and balance may be more affected without visual feedback. Simulated gestational weight gain resulted in worse gait function at both self-selected and maximum speeds.

Acute and chronic effects of static stretching at 100% versus 120% intensity on flexibility.

PURPOSE: The acute effects of static stretching have been frequently studied, but the chronic effects have not been studied concurrently. Thus, this study aimed to investigate both the acute and chronic effects of static stretching at different intensities on flexibility. METHODS: Twenty-three healthy men were randomly assigned to perform 1 min of static stretching 3 days/week for 4 weeks at 100% intensity (n = 12) or 120% intensity (n = 11). The acute effects of stretching were assessed by measuring the range of motion (ROM), peak passive torque, and passive stiffness before and after every stretching session; the chronic effects of stretching were assessed by measuring these outcomes at baseline and after 2 and 4 weeks of stretching. RESULTS: Compared with the 100% intensity group, the 120% intensity group had significantly greater acute increases in ROM after all 12 sessions, a significantly greater decrease in passive stiffness after 11 of 12 sessions, and a significantly greater increase in peak passive torque after six of 12 sessions. Regarding the chronic effects, ROM was significantly increased in both groups after 2 and 4 weeks of stretching. Peak passive torque significantly increased in the 100% intensity group after 2 and 4 weeks of stretching, and after 4 weeks in the 120% intensity group. CONCLUSION: Stretching at 120% intensity resulted in significantly greater acute improvements in ROM, peak passive torque, and stiffness than stretching at 100% intensity. Four weeks of stretching increased ROM and peak passive torque but did not decrease passive stiffness, regardless of the stretching intensity.

Application of the novel estimation method by shear wave elastography using vibrator to human skeletal muscle.

In recent years, non-invasive measurement of tissue stiffness (hardness) using ultrasound elastography has attracted considerable attention. It has been used to evaluate muscle stiffness in the fields of rehabilitation, sports, and orthopedics. However, ultrasonic diagnostic devices with elastography systems are expensive and clinical use of such devices has been limited. In this study, we proposed a novel estimation method for vibration-based shear wave elastography measurement of human skeletal muscle, then determined its reproducibility and reliability. The coefficient of variation and correlation coefficient were used to determine reproducibility and reliability of the method by measuring the shear wave velocities in konjac phantom gels and agar phantom gels, as well as skeletal muscle. The intra-day, day-to-day, and inter-operator reliabilities were good when measuring the shear wave velocities in phantom gels. The intra-day and day-to-day reliabilities were good when measuring the shear wave velocities in skeletal muscle. The findings confirmed adequate reproducibility and reliability of the novel estimation method for vibration-based shear wave elastography. Therefore, the proposed measurement method may be a useful tool for evaluation of muscle stiffness.

Median nerve injury does not contribute to early onset of decreased grip strength due to repetitive reaching and grasping tasks in rats.

BACKGROUND: Workplace risk factors, such as repetitive tasks, can cause work-related musculoskeletal disorders. In a rat model, decreased grip strength and median nerve injury develop following repetitive reaching and grasping tasks, involving negligible force. OBJECTIVE: We investigated whether median nerve injury is involved in the early onset of decreased grip strength due to such tasks METHODS: Sprague-Dawley rats were divided into: non-task-performing (0-week) and task-performing (1-, 2-, and 3-week) groups. After an initial training period, the task-performing groups continued to perform the task for 2 h/day, 3 days/week, for 1-3 weeks. Grip strength and relative muscle weight of the flexor digitorum superficialis (FDS) muscle were measured. Median nerve injury was evaluated by histopathology and immunohistochemistry. RESULTS: Grip strength of the reach limb (forelimb used in tasks) was significantly lower in the 3-week group compared with the other groups and was significantly lower than that of the non-reach limb in all groups. There were no significant differences in the relative FDS muscle weights of either limb among groups. No evidence of median nerve demyelination was observed and no cells expressed activating transcription factor-3, a specific marker of peripheral nerve injury, in the anterior horn of the spinal cord. CONCLUSION: Median nerve injury does not contribute to the decreased grip strength caused by 3 weeks of repetitive reaching and grasping tasks, involving negligible force, in rats.

The protective role of localized nitric oxide production during inflammation may be mediated by the heme oxygenase-1/carbon monoxide pathway.

Nitric oxide (NO) is an important part of the host defense mechanism; however, it displays both pro- and anti-inflammatory properties depending on its location and concentration. Importantly, excessive or inappropriate NO production can cause tissue damage. Systemic and local administration of NO synthase (NOS) inhibitors ameliorates and may exacerbate the inflammatory response, respectively. Here, we used a carrageenan-induced pleurisy model of acute inflammation in rats to confirm the location-dependent effects of NO and investigate the underlying mechanisms. As expected, localized suppression of NO production exacerbated inflammation, as evidenced by increased pleural exudate volumes and leukocyte counts and enhanced activity of enzymes related to oxidative stress. In contrast, local NO supplementation reduced leukocyte infiltration, vascular permeability, and the activity of oxidative stress-related enzymes. Interestingly, inhibition of heme oxygenase-1 (HO-1) reversed the anti-inflammatory effects of localized NO production, while the addition of hemin (HO-1 substrate) or carbon monoxide (CO; HO-1 metabolite) decreased leukocyte migration and exudation. Together, these findings confirm a protective role for NO at the inflammatory site, which appears to be mediated via NOS induction of the HO-1/CO pathway. Thus, NO supplementation may be a potential new treatment for oxidative stress-associated inflammatory diseases.

Changes in Flexibility and Force are not Different after Static Versus Dynamic Stretching.

In this study, we examined the effects of static and dynamic stretching on range of motion (ROM), passive torque (PT) at pain onset, passive stiffness, and isometric muscle force. We conducted a randomized crossover trial in which 16 healthy young men performed a total of 300 s of active static or dynamic stretching of the right knee flexors on two separate days in random order. To assess the effects of stretching, we measured the ROM, PT at pain onset, passive stiffness during passive knee extension, and maximum voluntary isometric knee flexion force using an isokinetic dynamometer immediately before and after stretching. Both static and dynamic stretching significantly increased the ROM and PT at pain onset (p<0.01) and significantly decreased the passive stiffness and isometric knee flexion force immediately after stretching (p<0.01). However, the magnitude of change did not differ between the two stretching methods for any measurements. Our results suggest that 300 s of either static or dynamic stretching can increase flexibility and decrease isometric muscle force; however, the effects of stretching do not appear to differ between the two stretching methods.

Evaluating pelvic floor muscle contractility using two-dimensional transperineal ultrasonography in patients with pelvic organ prolapse.

AIM: The hiatal anterior-posterior distance (APD), as measured by two-dimensional (2D) transperineal ultrasonography, is an indicator of pelvic floor muscle (PFM) contractility. The function of the pelvic floor is independently related to pelvic organ prolapse (POP) severity. However, little evidence concerning the APD for patients with POP before and after PFM training (PFMT) has been published. Therefore, we analyzed 2D transperineal ultrasonography in women with POP. METHODS: Twenty-eight women with POP completed a physiotherapist-led PFMT regimen that consisted of 4 months of one-on-one PFMT and lifestyle advice. The APD was measured using 2D transperineal ultrasonography immediately before and after the PFMT period and used to calculate ΔAPD (APD at rest-APD during contraction). Vaginal squeeze pressure during maximum voluntary contractions was also assessed using a manometer. We then analyzed the reliability and the correlation between ΔAPD as measured using 2D transperineal ultrasonography and vaginal squeeze pressure before and after PFMT. RESULTS: The APD at rest and during PFM contractions demonstrated intraclass correlation coefficients (ICCs) of 0.89 and 0.88, respectively. The ICC of maximal vaginal squeeze pressure was 0.97 during PFM contractions. Both ΔAPD (P < 0.01) and PFM strength (P < 0.05) increased significantly after PFMT. PFM strength and ΔAPD were correlated before (R = 0.53) and after (R = 0.68) PFMT (P < 0.01). CONCLUSIONS: We demonstrated that dynamic 2D transperineal ultrasonography could be used for studying functional changes in patients with POP. The ΔAPD of the levator hiatus has potential as an anatomical surrogate marker for evaluating PFM function in hospitals.

Dynamic Stretching Has Sustained Effects on Range of Motion and Passive Stiffness of the Hamstring Muscles.

Dynamic stretching (DS) is often performed during warm-up to help avoid hamstring muscle injuries, increase joint flexibility, and optimize performance. We examined the effects of DS of the hamstring muscles on passive knee extension range of motion (ROM), passive torque (PT) at the onset of pain (as a measure of stretch tolerance), and passive stiffness of the muscle-tendon unit over an extended period after stretching. Twenty-four healthy subjects participated, with 12 each in the experimental and control groups. Stretching was performed, and measurements were recorded using an isokinetic dynamometer pre-intervention, and at 0, 15, 30, 45, 60, 75, and 90 min post-intervention. DS consisted of ten 30-s sets of 15 repetitions of extension and relaxation of the hamstrings. ROM increased significantly (range, 7%-10%) immediately after DS, and the increase was sustained over 90 min. PT at the onset of pain also increased immediately by 10% but returned to baseline by 30 min. Passive stiffness decreased significantly (range, 7.9%-16.7%) immediately after DS, and the decrease was sustained over 90 min. Post-DS values were normalized to pre-DS values for the respective outcomes in both groups. ROM was significantly higher (range, 7.4%-10%) and passive stiffness was significantly lower (range, 5.4%-14.9%) in the experimental group relative to the control group at all time points. Normalized PT values at the onset of pain were significantly higher in the experimental group at 0-15 min than in the controls, but the differences were smaller at 30-45 min and not significant thereafter. We conclude that DS increases ROM and decreases passive stiffness in a sustained manner, and increases PT at the onset of pain for a shorter period. Overall, our results indicate that when performed prior to exercise, DS is beneficial for the hamstring muscles in terms of increasing flexibility and reducing stiffness.

Hamstring Stiffness Returns More Rapidly After Static Stretching Than Range of Motion, Stretch Tolerance, and Isometric Peak Torque.

Context: Hamstring injuries are common, and lack of hamstring flexibility may predispose to injury. Static stretching not only increases range of motion (ROM) but also results in reduced muscle strength after stretching. The effects of stretching on the hamstring muscles and the duration of these effects remain unclear. Objective: To determine the effects of static stretching on the hamstrings and the duration of these effects. Design: Randomized crossover study. Setting: University laboratory. Participants: A total of 24 healthy volunteers. Interventions: The torque-angle relationship (ROM, passive torque [PT] at the onset of pain, and passive stiffness) and isometric muscle force using an isokinetic dynamometer were measured. After a 60-minute rest, the ROM of the dynamometer was set at the maximum tolerable intensity; this position was maintained for 300 seconds, while static PT was measured continuously. The torque-angle relationship and isometric muscle force after rest periods of 10, 20, and 30 minutes were remeasured. Main Outcome Measures: Change in static PT during stretching and changes in ROM, PT at the onset of pain, passive stiffness, and isometric muscle force before stretching were compared with 10, 20, and 30 minutes after stretching. Results: Static PT decreased significantly during stretching. Passive stiffness decreased significantly 10 and 20 minutes after stretching, but there was no significant prestretching versus poststretching difference after 30 minutes. PT at the onset of pain and ROM increased significantly after stretching at all rest intervals, while isometric muscle force decreased significantly after all rest intervals. Conclusions: The effect of static stretching on passive stiffness of the hamstrings was not maintained as long as the changes in ROM, stretch tolerance, and isometric muscle force. Therefore, frequent stretching is necessary to improve the viscoelasticity of the muscle-tendon unit. Muscle force decreased for 30 minutes after stretching; this should be considered prior to activities requiring maximal muscle strength.

Discordant Relationship Between Evaluation of Facial Expression and Subjective Pain Rating Due to the Low Pain Magnitude.

INTRODUCTION: Facial expression to pain is an important pain indicator; however, facial movements look unresponsive when perceiving mild pain. The present study investigates whether pain magnitude modulates the relationship between subjective pain rating and an observer's evaluation of facial expression. METHODS: Twelve healthy volunteers were recruited to obtain 108 samples for pain rating with Visual Analogue Scale (VAS). Subjects underwent three different mechanical painful stimuli (monofilament forces of 100 g, 300 g, and 600 g) over three sessions and their facial expressions were videotaped throughout all sessions. Three observers independently evaluated facial expression of the subjects with a four-point categorical scale (no pain, mild pain, moderate pain, and severe pain). The correlations between subjective pain ratings and the evaluation of facial expression were analyzed in dichotomous group which was low pain ratings (VAS<30), or high pain rating (VAS≥30). RESULTS: Subjective pain ratings was significantly correlated with the evaluation of facial expression in high pain ratings, however no correlation was found between them in mild pain ratings. In mild pain ratings, most of the subjects (78%) were rated as no pain by observers, despite the fact that subjects reported pain. CONCLUSION: The results suggest that the evaluation of facial expression of pain was difficult for the observer to detect pain severity when the subjects feel mild pain.

Medium-term follow-up after supervised pelvic floor muscle training for patients with anterior vaginal wall prolapse.

OBJECTIVE: The objective of this study was to determine changes in quality of life, urogenital symptoms, and adherence to pelvic floor muscle training (PFMT) for pelvic organ prolapse (POP) in the medium term. STUDY DESIGN: The present study conducted a pretest-posttest quasi-experimental study design. Of 29 participants in 4-month supervised PFMT, 27 completed all assessments in a follow-up study. Twenty subjects were included in final analysis except 7 participants who underwent surgery during follow-up. To evaluate urogenital symptoms, they completed a prolapse-quality of life (P-QOL) questionnaire and POP-specific QOL. A urologist evaluated the prolapse status of all participants with POP-Q. In addition, the participants were asked about their adherence to PFMT, PFMT obstacles, and where PFMT was performed. All outcome measures were assessed at the following three time points: before PFMT, immediately after PFMT with one-on-one session, and at follow-up via a phone call. Values of p < 0.05 were considered significant. RESULTS: Of the 29 participants in the 4-month supervised PFMT, 27 completed all assessments in a follow-up study (response rate: 93.1%). The percentages of patients who continued PFMT at least 4 times declined substantially in non-operated at follow-up compared with supervised PFMT period. POP-specific QOL such as general health, prolapse impact, and role limitation were significantly worse at follow-up compared with immediately after PFMT despite initial improvement in the short term (p < 0.05). CONCLUSION: POP-specific QOL gradually worsened compared with patients immediately after supervised PFMT in mild to moderate POP women who were followed up without surgery at a 2-year follow-up. Adherence to home-based PFMT might decline without further supervision. It might indicate that to PFMT would be required to maintain symptoms and QOL in medium term. Further study will be needed to clarify if PFMT is effective to improve urogenital symptoms and QOL in long term among the patients with POP.

Decreased grip strength, muscle pain, and atrophy occur in rats following long-term exposure to excessive repetitive motion.

Work-related musculoskeletal disorders (WMSD) are caused by the overuse of muscles in the workplace. Performing repetitive tasks is a primary risk factor for the development of WMSD. Many workers in highly repetitive jobs exhibit muscle pain and decline in handgrip strength, yet the mechanisms underlying these dysfunctions are poorly understood. In our study, rats performed voluntary repetitive reaching and grasping tasks (Task group), while Control group rats did not perform these activities. In the Task group, grip strength and forearm flexor withdrawal threshold declined significantly from week 2 to week 6, compared with these values at week 0 (P < 0.05). Relative muscle weight and muscle fiber cross-sectional area of flexor digitorum superficialis (FDS) muscles decreased significantly in the Task group, compared with the Control group, at 6 weeks (P < 0.05 and P < 0.01, respectively). Nerve growth factor, glial cell line-derived neurotrophic factor, and tumor necrosis factor α-expression in FDS muscles were not significantly different in Control and Task groups at 3 and 6 weeks. At 6 weeks, the Task group had elevated MuRF1 protein levels (P = 0.065) and significant overexpression of the autophagy-related (Atg) proteins, Beclin1 and Atg5-Atg12, compared with in the Control group (both P < 0.05). These data suggested that long-term exposure to excessive repetitive motion causes loss of grip strength, muscle pain, and skeletal muscle atrophy. Furthermore, this exposure may enhance protein degradation through both the ubiquitin-proteasome and autophagy-lysosome systems, thereby decreasing skeletal muscle mass.

Evaluation of irreversible protein thermal inactivation caused by breakage of disulphide bonds using methanethiosulphonate.

Many extracellular globular proteins have evolved to possess disulphide bonds in their native conformations, which aids in thermodynamic stabilisation. However, disulphide bond breakage by heating leads to irreversible protein denaturation through disulphide-thiol exchange reactions. In this study, we demonstrate that methanethiosulphonate (MTS) specifically suppresses the heat-induced disulphide-thiol exchange reaction, thus improving the heat-resistance of proteins. In the presence of MTS, small globular proteins that contain disulphides can spontaneously refold from heat-denatured states, maintaining wild-type disulphide pairing. Because the disulphide-thiol exchange reaction is triggered by the generation of catalytic amounts of perthiol or thiol, rapid and specific perthiol/thiol protection by MTS reagents prevents irreversible denaturation. Combining MTS reagents with another additive that suppresses chemical modifications, glycinamide, further enhanced protein stabilisation. In the presence of these additives, reliable remnant activities were observed even after autoclaving. However, immunoglobulin G and biotin-binding protein, which are both composed of tetrameric quaternary structures, failed to refold from heat-denatured states, presumably due to chaperon requirements. Elucidation of the chemical modifications involved in irreversible thermoinactivation is useful for the development of preservation buffers with optimum constitutions for specific proteins. In addition, the impact of disulphide bond breakage on the thermoinactivation of proteins can be evaluated using MTS reagents.

Physical activity and pelvic floor muscle training in patients with pelvic organ prolapse: a pilot study.

INTRODUCTION AND HYPOTHESIS: The details of the physical activity in patients with mild to moderate pelvic organ prolapse (Pmoderate pelvic organ prolapse (POP) remain under-studied. The purpose of the present study was to investigate objective physical activity levels and the changes in pelvic floor muscle(PFM) strength, symptoms and quality of life (QOL) between before and after PFM training (PFMT) in patients with POP. METHODS: In a prospective pilot study, 29 patients with stage II or III POP completed approximately 16 weeks of PFMT. A reliable activity monitor was used to measure physical activity parameters including step counts, activity and total calories expended, and duration at each intensity level. Maximum vaginal squeeze pressure, POP symptoms and QOL were assessed. Changes in these outcome measures were compared before and after PFMT. RESULTS: The step counts per day (mean ± SD) of women with POP was 7,272.9 ± 3,091.7 before PFMT and 7,553.4 ± 2,831.0 after PFMT. There was no significant change between before and PFMT. PFM strength was significantly increased after PFMT. POP-related symptoms including stress urinary incontinence, frequency, postmicturition dribble and interference with emptying the bowels were significantly improved. The QOL scores for general health, physical limitations, emotion, and severity measures were significantly improved after PFMT. CONCLUSIONS: Although PFMT changed PFM strength symptoms, and QOL, there were no changes for any physical activity parameters before and after PFMT. This is probably because the physical activity levels in patients with mild to moderate POP were almost same as in age-matched healthy women.

Acute Effects of the Different Intensity of Static Stretching on Flexibility and Isometric Muscle Force.

Kataura, S, Suzuki, S, Matsuo, S, Hatano, G, Iwata, M, Yokoi, K, Tsuchida, W, Banno, Y, and Asai, Y. Acute effects of the different intensity of static stretching on flexibility and isometric muscle force. J Strength Cond Res 31(12): 3403-3410, 2017-In various fields, static stretching is commonly performed to improve flexibility, whereas the acute effects of different stretch intensities are unclear. Therefore, we investigated the acute effects of different stretch intensities on flexibility and muscle force. Eighteen healthy participants (9 men and 9 women) performed 180-second static stretches of the right hamstrings at 80, 100, and 120% of maximum tolerable intensity without stretching pain, in random order. The following outcomes were assessed as markers of lower limb function and flexibility: static passive torque (SPT), range of motion (ROM), passive joint (muscle-tendon) stiffness, passive torque (PT) at onset of pain, and isometric muscle force. Static passive torque was significantly decreased after all stretching intensities (p ≤ 0.05). Compared with before stretching at 100 and 120% intensities, ROM and PT were significantly increased after stretching (p ≤ 0.05), and passive stiffness (p = 0.05) and isometric muscle force (p ≤ 0.05) were significantly decreased. In addition, ROM was significantly greater after stretching at 100 and 120% than at 80%, and passive stiffness was significantly lower after 120% than after 80% (p ≤ 0.05). However, all measurements except SPT were unchanged after 80% intensity. There was a weak positive correlation between the intensities of stretching and the relative change for SPT (p ≤ 0.05), a moderate positive correlation with ROM (p ≤ 0.05), and a moderate positive correlation with passive stiffness (p ≤ 0.05). These results indicate that static stretching at greater intensity is more effective for increasing ROM and decreasing passive muscle-tendon stiffness.

Heat Stress Modulates Both Anabolic and Catabolic Signaling Pathways Preventing Dexamethasone-Induced Muscle Atrophy In Vitro.

It is generally recognized that synthetic glucocorticoids induce skeletal muscle weakness, and endogenous glucocorticoid levels increase in patients with muscle atrophy. It is reported that heat stress attenuates glucocorticoid-induced muscle atrophy; however, the mechanisms involved are unknown. Therefore, we examined the mechanisms underlying the effects of heat stress against glucocorticoid-induced muscle atrophy using C2C12 myotubes in vitro, focusing on expression of key molecules and signaling pathways involved in regulating protein synthesis and degradation. The synthetic glucocorticoid dexamethasone decreased myotube diameter and protein content, and heat stress prevented the morphological and biochemical glucocorticoid effects. Heat stress also attenuated increases in mRNAs of regulated in development and DNA damage responses 1 (REDD1) and Kruppel-like factor 15 (KLF15). Heat stress recovered the dexamethasone-induced inhibition of PI3K/Akt signaling. These data suggest that changes in anabolic and catabolic signals are involved in heat stress-induced protection against glucocorticoid-induced muscle atrophy. These results have a potentially broad clinical impact because elevated glucocorticoid levels are implicated in a wide range of diseases associated with muscle wasting. J. Cell. Physiol. 232: 650-664, 2017. © 2016 The Authors. Journal of Cellular Physiology published by Wiley Periodicals, Inc.

Higher pain rating results in lower variability of somatosensory cortex activation by painful mechanical stimuli: An fMRI study.

OBJECTIVE: The aim of this study was to find pain-related brain activity which corresponds to self-report pain ratings based on degree of response and repeatability. METHODS: Three painful mechanical stimuli were applied to the right hands of 25 healthy volunteers using monofilaments (forces of 0.98N, 2.94N, and 5.88N). Simultaneously, brain activities were evaluated using functional MRI for a constant stimulus conducted three times in a session. In first assessment, the average percent signal change (PSC) of neuronal response was measured for each region of interest (ROI), secondary repeatability of PSC conducted three times over the session was evaluated for each ROI. RESULTS: Although the average PSCs for trice stimuli conducted in one session increased in accordance with pain ratings in the somatosensory cortex (S1) and anterior cingulate cortex (ACC), there was a different response between S1 and ACC when subjects rated intense pain; a stable response in S1 against a variable response in ACC. CONCLUSIONS: These results imply that there are different cognitive responses between sensory discrimination and affective component to constant painful stimulus each time. SIGNIFICANCE: Consistency of brain activity based on PSC may be an important biomarker which, along with its neuronal activity, gauges self-report pain ratings.