Muscle Exercise Research Articles

The Effect of Balance-Resistance Training on the Immunity Levels and Physical Fitness of Children With Cerebral Palsy

Background and Aims Cerebral palsy is a non-specific and descriptive term referring to motor dysfunction in early childhood. The disease is non-progressive and is caused by permanent damage to the developing brain. This study aimed to investigate the effect of balance-resistance training on the immunity levels and physical fitness of children with cerebral palsy. Methods The present study was quasi-experimental and employed a pret-est-post-test design with a control group. For this study, 30 children (6-10 years) with cerebral palsy were recruited and divided into two groups (15 in the experimental group and 15 in the control group). The experimental group took part in resistance and balance exercises (resistance exercises for knee flexor muscles, knee extensor, and ankle extensor and free balance exercises in two levels of stable support and appropriate level of support) for 8 weeks, 3 sessions per week and each session lasted for 45 minutes. All dependent variables of the research (immunoglobulin A index, cardiorespiratory endurance, flexibility, muscle strength, muscle endurance, and body composition) were measured in two rounds of pre-test and post-test. To analyze the data, the independent t test, paired t test, 2-way analysis of variance, and Bonferroni test were used at a significance level of 0.05. All statistical analyses were performed using SPSS software, version 24. Results The results showed that combined resistance-balance training has a significant effect on immunity levels (immunoglobulin A), maximum oxygen consumption, flexibility, muscle strength, muscle endurance, and body composition of children with cerebral palsy (P≤0.001). Conclusion Patients with cerebral palsy are recommended to benefit from these exercises and medical treatments. The advantage of such adjuvant methods over medical therapies is that there are no side effects.

Genomic and epigenomic changes by low force electrically induced exercise of human paralyzed muscle

Musculoskeletal deterioration following complete paralysis, such as after a spinal cord injury, results in osteoporotic bone and atrophic, glycolytic, and insulin-resistant skeletal muscle. Decreased bone integrity can be overloaded with very little force; therefore, high force contractions should be avoided in people with long-term spinal cord injury. Together, these changes compromise systemic metabolism for people with SCI and contribute to the development of secondary non-communicable diseases. Electrically induced exercise training offers a unique strategy to ensure full muscle recruitment without high force levels by using high current intensity and a low stimulation frequency (<5Hz) to prevent force summation of stimulus pulses. While acute epigenomic and genomic changes have been found with this low force exercise method; how long-term training affects skeletal muscle and systemic biomarkers of health remains unknown. Purpose: We seek to determine the long-term genomic and epigenomic response of low-force electrically induced exercise in paralyzed skeletal muscle. Methods: 10 males with a complete SCI completed at least 6-months of unilateral electrically induced exercise training using low-force (3Hz) stimulation. Participants completed at least 5 exercise training sessions per week for at least 6-months. A muscle fatigue assessment and fasting venous blood draw were performed before and after training. Percutaneous muscle biopsies were obtained from a trained and untrained vastus lateralis. Gene expression was measured using the Affymetrix HTA 2.0 array and epigenomic expression was measured using Illumina’s MethylEPIC array. Parametric tests were used to compare pre and post training. All participants provided written consent approved by the University of Iowa Institutional Review Board in compliance with the Declaration of Helsinki. Results: Participants maintained a high compliance by completing 119±19% of the training sessions for 7.2±1.2 months. There was a 115±34% change improvement of the fatigue index after training (p=0.002). Serum concentrations of insulin, hsCRP, and myostatin were decreased by 43±8% (p=0.155), 26±8%(p=0.047), 35±9%(p=0.098) after exercise training, respectively. Serum BDNF increased by 68±14%(p=0.093) after exercise training. There was a strong correlation between the primary principal component and the trained limb (R2=0.20, p=0.046). There were 693 and 671 genes to be significantly up or down regulated after exercise training (FDR < 0.05). Of the genes most responsive to exercise training, MYH6, MYH7, and MYL3 were increased in expression and decreased in median methylation. MSTN and ACTN3 were decreased in genomic expression with an increase in median methylation after exercise training. Conclusions: Low-force electrically induced exercise training improved fatigability, a muscle oxidative phenotype transition, and improved serum biomarkers associated with metabolism and inflammation. Together, these data highlight the impact low-force electrically induced exercise can have on paralyzed muscle and is suggestive that this rehabilitation strategy may provide benefits for people living with paralysis. Research Support: This study was funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development: R01HD084645, R01HD082109. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Quantifying in vivo Mitochondrial Effciency at Rest and during Exercise in Human Skeletal Muscle

Introduction: Mitochondrial effciency provides an additional mechanism to fine-tune oxidative phosphorylation rate to match ATP demand in skeletal muscle with far-reaching consequences on exercise tolerance. However, the direct measurement of both oxygen consumption (VO2) and ATP production from the same region of the contracting muscle in vivo remains a technical challenge. Purpose: Using an innovative approach combining noninvasive phosphorus and proton magnetic resonance spectroscopy (31P/1H-MRS), the present study aimed to characterize skeletal muscle ATP synthesis rate and muscle VO2 at rest and during a graded dynamic plantar flexion exercise to determine mitochondrial effciency in the gastrocnemius muscle. Method: We assessed mitochondrial effciency in the gastrocnemius muscles of 12 healthy adults (21± 1 yrs.). 31P and 1H magnetic resonance spectroscopy (MRS) was performed using a whole-body 3T MR system (Skyra, Siemens) at rest and during a series of constant workloads coupled to brief transient ischemia to quantify both oxidative ATP synthesis (ATPox) rate and myoglobin-derived oxygen consumption (Mb-derived VO2). The MRS data were acquired with a dual-tuned 31P/1H surface coil with linear polarization positioned over the gastrocnemius muscle. Results: As expected, the end-exercise PCr concentration decreased from 29 ± 2 mM of WRmax to 18 ± 1 mM with increasing workload. Likewise, the end-exercise Mb oxygenation level declined linearly with increasing workload. As the exercise workload increased, the ATPox synthesis rate increased linearly (r2 = 0.45), whereas there was no significant change in Mb-derived VO2. At rest, the estimated P/O ratio in the gastrocnemius muscle was 1.95 ± 0.68, whereas non-physiological values were obtained during exercise. Conclusion: During exercise, Mb-derived VO2 was likely limited by O2 availability with the methodology employed (30-sec occlusion, spectrum time resolution of 10 sec), which precluded the accurate quantification of mitochondrial effciency. However, mitochondrial effciency calculated at rest is in agreement with previously documented values ex vivo and thus provides an additional parameter to evaluate mitochondrial function in vivo. This work was funded in part by National Heart, Lung, and Blood Institute Grant R00HL125756. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

EXPLORING THE ROLE OF SKELETAL MUSCLE MICROVASCULAR BLOOD FLOW IN EXERCISE CAPACITY AMONG INDIVIDUALS WITH CONTROLLED TYPE 2 DIABETES

INTRODUCTION & AIMS The cardiac and macrovascular system is vital for human exercise capacity, yet the microvascular network is primarily responsible for delivering nutrients and oxygen to metabolically active tissues like skeletal muscle. Due to methodological limitations, few studies have investigated the role of muscle microvascular blood flow in determining exercise capacity or intolerance in individuals with chronic conditions such as type 2 diabetes. Our aim was to use modern contrast-enhanced ultrasound to directly measure microvascular blood flow in skeletal muscle at rest and after a maximal treadmill exercise test in individuals with controlled type 2 diabetes. METHODS Fifteen adults with controlled type 2 diabetes (age: 62.5 ± 8.0 years [M ± SD]; BMI: 31.6 ± 6.9 kg/m2; HbA1c: 6.7 ± 0.9%; 13 females and 2 male) attended the laboratory after a 2-hour fast and completed a Modified Bruce treadmill exercise test until exhaustion. Microvascular blood velocity, volume, and flow in the vastus lateralis muscle was assessed at rest, immediately post-exercise, and 30 minutes post-exercise via contrast-enhanced ultrasound during a constant-rate intravenous contrast agent infusion (DEFINITY®). Participants also completed a whole-body dual x-ray absorptiometry scan and a six-minute walk test (6MWT). RESULTS Microvascular blood velocity, volume, and flow increased immediately after exercise (∼230%, ∼79%, and ∼529%, respectively; all p<0.001), and remained elevated above baseline levels 30 minutes post-exercise (∼79%, ∼25%, and ∼139%, respectively; all p≤0.003). Resting and post-exercise skeletal muscle microvascular blood flow measures were not associated with VO2peak (ml/min/kg), time to exhaustion, or six-minute walk distance (all p>0.05). CONCLUSION Muscle microvascular blood flow remains elevated for up to 30 minutes following maximal aerobic exercise in individuals with controlled type 2 diabetes. The lack of association between muscle microvascular blood flow and exercise capacity is not clear but may indicate considerable blood flow redundancy or reserve within the vascular network.

Central command activation during exercise is essential for the bradycardic response to diving

Mammalian diving response evokes complex cardiovascular adjustments, including bradycardia during sustained muscular activity. This is intriguing because voluntary exercise involves the activation of central command and skeletal muscle afferents, known to provoke tachycardia by reducing vagal outflow and increasing cardiac sympathetic activity. Nonetheless, it is currently unknown how diving-induced bradycardia can override the exercise tachycardia. Given this, we aimed to test the hypothesis that central and peripheral afferent mechanisms interact to modulate this physiological phenomenon. In three visits, 32 healthy subjects (15 women; 22±3 yr) were exposed to trigeminal nerve stimulation (i.e., facial cooling; TGS) to partially activate the diving reflex at rest (semi-recumbent position) and under three protocols: 1) during voluntary light (resting heart rate+20 beats.min−1) and moderate (resting heart rate+50 beats.min−1) steady-state cycling exercise; 2) during isolation of peripheral afferent reflexes via passive exercise (muscle mechanoreceptors) and cold pressor test (nociceptors; CPT), and; 3) during CPT with concurrent light exercise. The exercise intensities were assumed to provide different levels of central command activation, while both passive exercise and CPT were used to provide insights into the contribution of central command to diving bradycardia. TGS was performed for at least 90 seconds in all conditions. Beat-to-beat heart rate (HR, by electrocardiography) and blood pressure (finger photoplethysmography) were continuously measured, and surface electromyography was used to ensure the lack of volitional component during passive exercise. TGS elicited significant bradycardia at rest (Δ-12±0.9 beats·min−1; P<0.001), and this response was increased during voluntary light exercise (Δ-15±1.2 beats·min−1; P=0.002), but unaffected during voluntary moderate exercise when compared to rest (Δ-11±1.3 beats·min−1; P=0.536). In contrast, compared to rest, the HR response to TGS during passive exercise was significantly attenuated (Δ-13±1.2 beats·min−1 vs. Δ-9±1.7 beats·min−1; P=0.039), whereas CPT completely abolish the diving bradycardic response (Δ0±1.6 beats·min−1; P<0.001). However, when the volitional component was restored during CPT with concurrent light exercise, TGS provoked a significant bradycardic response, when compared to CPT condition (Δ1±1.6 beats·min−1 vs. Δ-10±2.1 beats·min−1; P=0.004). Notably, our findings were not affected by sex. In conclusion, these findings suggest that 1) central command activation during cycling exercise is essential for the bradycardic response to diving; 2) isolated peripheral afferent reflexes exert inhibitory feedback to modulate diving-induced bradycardia, and; 3) central and peripheral afferent feedback are important mechanisms by which exercise modulates the dive response. CNPq 307764/2022-2; CAPES (001). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Effects of a Sternocleidomastoid Muscle Exercise Protocol on Masticatory Muscles: A Case Study

Effects of a Sternocleidomastoid Muscle Exercise Protocol on Masticatory Muscles: A Case Study

The Effect of Pelvic Floor Rehabilitation on Low Anterior Resection Syndrome After Colorectal Cancer Treatment

Purpose: Low anterior resection (LAR) is the preferred surgical treatment of rectosigmoid or rectal cancers. However, it is often associated with bowel dysfunction, which is termed low anterior resection syndrome (LARS). Daily bowel dysfunction symptoms have a detrimental effect on quality of life (QOL). Pelvic floor rehabilitation (PFR) can improve pelvic floor function and QOL among patients with LARS. This quality improvement (QI) project seeks to assess the prevalence of LARS and develop and incorporate PFR for the treatment and prevention of LARS. Methods: A convenience sample of 20 patients met project inclusion. Thirteen patients participated. Individuals were categorized by diagnostic risk: low risk, high risk, and established. The intervention included 1-hour PFR sessions with the physical therapist (PT) and 5 minutes of daily self-led pelvic floor muscle exercises. Outcomes questionnaires included the LARS Score and Fecal Incontinence Quality of Life (FIQOL) Scale. Data were collected both pre- and post–colorectal cancer treatment. Results: The overall prevalence of LARS was 76.9%, which was significantly higher than the retrospective cohort comparison rate of 21.8% (p < .001). The prevalence of major LARS was 89%, 83%, and 50% at the initial, second, and third sessions, respectively, representing a 44% relative decrease. Embarrassment was significantly affected among individuals with major LARS, although ongoing PFR facilitated improvement. Conclusion: PFR is a valuable adjunct therapy for LARS, with continued sessions decreasing the overall prevalence among the cohort. Major LARS negatively impacts QOL measures early on in treatment but improves with continued PFR.

Functional Disability Due to Chronic Low Back Pain in the Geriatric Population of a Tertiary Care Hospital in North India: A Cross-Sectional Study.

Background Chronic low back pain (CLBP) is one of the painful and disabling conditions affecting the young as well as the geriatric population. There is a limited body of research to find out the impact of CLBP and functional disability on geriatric adults in the Indian region. Aim This study aims to determine the prevalence of functional disability due to CLBP in the geriatric population and to investigate the correlation between functional disability due to CLBP and other sociodemographic factors. Methodology A total of 157 geriatric adults were enrolled in the study, fulfilling the inclusion and exclusion criteria. Basic sociodemographic data, along with a clinical-radiological examination, was recorded. The Numeric Pain Rating Scale (NPRS), the Roland and Morris Disability Questionnaire, and the Quebec Back Pain Disability Scale were used as study tools. Summary measures (frequency, mean, median, etc.) are calculated according to the level of measurement of variables. The point prevalence of functional disability due to CLBP in the geriatric population, along with 95% confidence intervals, has been calculated. The prevalence estimates were estimated and calculated with SD variables using a t-test, chi-square test, or Fisher's exact test under bivariate analysis. The linear/logistic regression analysis was used to control for the effects of covariates. A significance level of 5% was set for all analyses due to the exploratory nature of the study. Statistical significance was considered at p < 0.05. Results According to the Roland and Morris Disability Questionnaire, 29% (N = 46) of the study geriatric participants had a severe disability, 45% (N = 70) had a moderate disability, and 26% (N = 41) had a mild disability. According to the Quebec Back Pain Disability Scale, 34% (N = 53) had scored more than 50, and 66% (N = 104) had scored less than 50. Statistically significant correlations have been found between the level of functional disability and intensity of pain (NPRS score), gender, associated illness, current and past occupation, and clinical diagnosis of CLBP (p < 0.05). Conclusion The prevalence of functional disability due to CLBP is higher in the geriatric population. It is associated with many influencing sociodemographic factors like gender, occupation, associated musculoskeletal illness, the intensity of low back pain, and clinico-radiological diagnosis. Early identification and timely interventions to reduce functional disability due to CLBP and associated risk factors are the need of the hour. Regular back muscle exercises, ergonomic modifications, and modification of activities of daily life are recommended to prevent functional disability due to CLBP.

The Effects of Various Approaches to Lobectomies on Respiratory Muscle Strength, Diaphragm Thickness, and Exercise Capacity in Lung Cancer

BackgroundThe most common surgery for non-small cell lung cancer is lobectomy, which can be performed through either thoracotomy or video-assisted thoracic surgery (VATS). Insufficient research has examined respiratory muscle function and exercise capacity in lobectomy performed using conventional thoracotomy (CT), muscle-sparing thoracotomy (MST), or VATS. This study aimed to assess and compare respiratory muscle strength, diaphragm thickness, and exercise capacity in lobectomy using CT, MST, and VATS.MethodsThe primary outcomes were changes in respiratory muscle strength, diaphragm thickness, and exercise capacity. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were recorded for respiratory muscle strength. The 6-min walk test (6MWT) was used to assess functional exercise capacity. Diaphragm thickness was measured using B-mode ultrasound.ResultsThe study included 42 individuals with lung cancer who underwent lobectomy via CT (n = 14), MST (n = 14), or VATS (n = 14). Assessments were performed on the day before surgery and on postoperative day 20 (range 17–25 days). The decrease in MIP (p < 0.001), MEP (p = 0.003), 6MWT (p < 0.001) values were lower in the VATS group than in the CT group. The decrease in 6MWT distance was lower in the MST group than in the CT group (p = 0.012). No significant differences were found among the groups in terms of diaphragmatic muscle thickness (p > 0.05).ConclusionThe VATS technique appears superior to the CT technique in terms of preserving respiratory muscle strength and functional exercise capacity. Thoracic surgeons should refer patients to physiotherapists before lobectomy, especially patients undergoing CT. If lobectomy with VATS will be technically difficult, MST may be an option preferable to CT because of its impact on exercise capacity.

Significant improvement in locomotive functions after total knee arthroplasty but worse than those of independent ambulatory community dwellers

PurposeThis study investigated the adequacy of improvements in locomotive syndrome (LS) and other clinical outcomes after total knee arthroplasty (TKA) for medial knee osteoarthritis. MethodsA total of 74 patients who underwent unilateral primary TKA were evaluated pre-operatively and 3, 6, and 12 months post-TKA using the 25-question Geriatric Locomotive Function Scale (GLFS-25) to evaluate the severity of LS, the Japanese Knee Osteoarthritis Measure (JKOM), the Knee Society Score (KSS), the timed up and go (TUG) test, and range of motion of the knee joint (ROM). The GLFS-25 score and the severity of LS were compared between these patients and independent ambulatory community dwellers (273 males and 477 females). ResultsThe GLFS-25, JKOM, KSS, TUG scores, and ROM significantly improved post-operatively. The pre-operative incidence of LS stage 3, indicating the worst locomotive function, decreased from 81.1% to 24.3% at the final follow-up. However, the median (interquartile range) GLFS-25 score of 13 (6–23) seemed much worse, and the incidence of LS stage 3 of 24.3% seemed much higher even 12 months post-TKA compared with independent ambulatory community dwellers. ConclusionsThe GLFS-25 score and other clinical outcome scales significantly improved after TKA. However, improvements in locomotive functions were not adequate as approximately 25% of patients remained with LS stage 3. Besides ordinary rehabilitation programmes after TKA, some interventions, such as more rigorous muscle exercises, would be necessary to obtain greater improvements in LS.

Inhibitory Regulation of FOXO1 in PPARδ Expression Drives Mitochondrial Dysfunction and Insulin Resistance.

Forkhead box protein O1 (FoxO1) regulates muscle growth, but the metabolic role of FoxO1 in skeletal muscle and its mechanisms remain unclear. To explore the metabolic role of FoxO1 in skeletal muscle, we generated skeletal muscle-specific FoxO1 inducible knockout (mFoxO1 iKO) mice and fed them a high-fat diet to induce obesity. We measured insulin sensitivity, fatty acid oxidation, mitochondrial function, and exercise capacity in obese mFoxO1 iKO mice, and assessed the correlation between FoxO1 and mitochondrial-related protein in the skeletal muscle of diabetic patients. Obese mFoxO1 iKO mice exhibited improved mitochondrial respiratory capacity, which was followed by attenuated insulin resistance, enhanced fatty acid oxidation, and improved skeletal muscle exercise capacity. Transcriptional inhibition of FoxO1 in peroxisome proliferator-activated receptor δ (PPARδ) expression was confirmed in skeletal muscle and deletion of PPARδ abolished the beneficial effects of FoxO1 deficiency. FoxO1 protein levels were higher in the skeletal muscle of diabetic patients and negatively correlated with PPARδ and electron transport chain protein levels. These findings highlight FoxO1 as a new repressor in PPARδ gene expression in skeletal muscle and suggest that FoxO1 links insulin resistance and mitochondrial dysfunction in skeletal muscle via PPARδ.

Low-Volume Speed Endurance Training with Reduced Volume Improves Short-Term Exercise Performance in Highly Trained Cyclists.

We investigated the effects of low- and high-volume speed endurance training (SET), with a reduced training volume, on sprint ability, short- and long-term exercise capacity, muscle mitochondrial properties, ion transport proteins, and maximal enzyme activity in highly trained athletes. Highly trained male cyclists (maximal oxygen consumption (V̇O 2max ): 68.3 ± 5.0 mL·min -1 ·kg -1 , n = 24) completed 6 wk of either low (SET-L; 6 × 30-s intervals, n = 8) or high (SET-H; 12 × 30-s intervals, n = 8) volume SET twice per week with a 30% reduction in training volume. A control group (CON; n = 8) maintained their training. Exercise performance was evaluated by i) 6-s sprinting, ii) a 4-min time trial, and iii) a 60-min preload at 60% V̇O 2max followed by a 20-min time trial. A biopsy of m. vastus lateralis was collected before and after the training intervention. In SET-L, 4-min time trial performance was improved ( P < 0.05) by 3.8%, with no change in SET-H and CON. Sprint ability, prolonged endurance exercise capacity, V̇O 2max , muscle mitochondrial respiratory capacity, maximal citrate synthase activity, fiber type-specific mitochondrial proteins (complexes I-V), and phosphofructokinase (PFK) content did not change in any of the groups. In SET-H, maximal activity of muscle PFK and abundance of Na + -K + pump-subunit α 1 , α 2 , β 1 , and phospholemman (FXYD1) were 20%, 50%, 19%, 24%, and 42% higher ( P < 0.05), respectively after compared with before the intervention, with no changes in SET-L or CON. Low SET volume combined with a reduced aerobic low- and moderate-intensity training volume does improve short-duration intense exercise performance and maintain sprinting ability, V̇O 2max , endurance exercise performance, and muscle oxidative capacity, whereas, high volume of SET seems necessary to upregulate muscle ion transporter content and maximal PFK activity in highly trained cyclists.

Effect of resistance circuit training on comprehensive health indicators in older adults: a systematic review and meta-analysis

The aging process leads to the degeneration of body structure and function. The objective of this study is to conduct a systematic review and meta-analysis of the effects of resistance circuit training (RCT) on comprehensive health indicators of older adults. PubMed, Embase, and Web of Science were searched until August 2023. Primary outcomes were body composition, muscle strength, cardiorespiratory endurance, blood pressure, and functional autonomy. Muscle function and exercise intensity subgroups were analyzed. RCT reduces body fat (MD = − 5.39 kg, 95% CI − 10.48 to − 0.29), BMI (MD = − 1.22, 95% CI − 2.17 to − 0.26), and body weight (MD = − 1.28 kg, 95% CI − 1.78 to − 0.78), and increases lean body mass (MD = 1.42 kg, 95% CI 0.83–2.01) in older adults. It improves upper limb strength (SMD = 2.09, 95% CI 1.7–2.48), lower limb strength (SMD = 2.03, 95% CI 1.56–2.51), cardiorespiratory endurance (MD = 94 m, 95% CI 25.69–162.67), and functional autonomy (MD = − 1.35, 95% CI − 1.73 to − 0.96). High-intensity RCT benefits BMI and body weight, while low-intensity exercise reduces blood pressure. RCT improves muscle function in push, pull, hip, and knee movements in older adults. RCT improves body composition, muscle strength, cardiorespiratory endurance, blood pressure, and functional autonomy in older adults. High-intensity training is superior for body composition, while moderate to low intensity training is more effective for lowering blood pressure.

Automated analysis of pectoralis major thickness in pec-fly exercises: evolving from manual measurement to deep learning techniques

This study addresses a limitation of prior research on pectoralis major (PMaj) thickness changes during the pectoralis fly exercise using a wearable ultrasound imaging setup. Although previous studies used manual measurement and subjective evaluation, it is important to acknowledge the subsequent limitations of automating widespread applications. We then employed a deep learning model for image segmentation and automated measurement to solve the problem and study the additional quantitative supplementary information that could be provided. Our results revealed increased PMaj thickness changes in the coronal plane within the probe detection region when real-time ultrasound imaging (RUSI) visual biofeedback was incorporated, regardless of load intensity (50% or 80% of one-repetition maximum). Additionally, participants showed uniform thickness changes in the PMaj in response to enhanced RUSI biofeedback. Notably, the differences in PMaj thickness changes between load intensities were reduced by RUSI biofeedback, suggesting altered muscle activation strategies. We identified the optimal measurement location for the maximal PMaj thickness close to the rib end and emphasized the lightweight applicability of our model for fitness training and muscle assessment. Further studies can refine load intensities, investigate diverse parameters, and employ different network models to enhance accuracy. This study contributes to our understanding of the effects of muscle physiology and exercise training.

The effect of respiratory muscle training on children and adolescents with cystic fibrosis: a systematic review and meta-analysis

BackgroundCystic fibrosis is a chronic genetic disease that can affect the function of the respiratory system. Previous reviews of the effects of respiratory muscle training in people with cystic fibrosis are uncertain and do not consider the effect of age on disease progression. This systematic review aims to determine the effectiveness of respiratory muscle training in the clinical outcomes of children and adolescents with cystic fibrosis.MethodsUp to July 2023, electronic databases and clinical trial registries were searched. Controlled clinical trials comparing respiratory muscle training with sham intervention or no intervention in children and adolescents with cystic fibrosis. The primary outcomes were respiratory muscle strength, respiratory muscle endurance, lung function, and cough. Secondary outcomes included exercise capacity, quality of life and adverse events. Two review authors independently extracted data and assessed study quality using the Cochrane Risk of Bias Tool 2. The certainty of the evidence was assessed according to the GRADE approach. Meta-analyses where possible; otherwise, take a qualitative approach.ResultsSix studies with a total of 151 participants met the inclusion criteria for this review. Two of the six included studies were published in abstract form only, limiting the available information. Four studies were parallel studies and two were cross-over designs. There were significant differences in the methods and quality of the methodology included in the studies. The pooled data showed no difference in respiratory muscle strength, lung function, and exercise capacity between the treatment and control groups. However, subgroup analyses suggest that inspiratory muscle training is beneficial in increasing maximal inspiratory pressure, and qualitative analyses suggest that respiratory muscle training may benefit respiratory muscle endurance without any adverse effects.ConclusionsThis systematic review and meta-analysis indicate that although the level of evidence indicating the benefits of respiratory muscle training is low, its clinical significance suggests that we further study the methodological quality to determine the effectiveness of training.Trial registrationThe protocol for this review was recorded in the International Prospective Register of Systematic Reviews (PROSPERO) under registration number CRD42023441829.

Endothelial dysfunction influences augmented aortic hemodynamic responses to metaboreflex activation in postmenopausal women.

Postmenopausal women experience augmented aortic hemodynamic responses to isometric handgrip (IHG) exercise and metaboreflex activation post-exercise muscle ischemia (PEMI). Relationships between endothelial function brachial artery flow-mediated dilation (FMD) and aortic stiffness carotid-femoral pulse wave velocity (cfPWV) with aortic pulsatile hemodynamics during IHG and PEMI have not been determined. The relationships between aortic hemodynamic responses to PEMI were evaluated. Aortic blood pressure (BP), wave reflection, and pressure of forward (Pf) and backward (Pb) waves were measured using arterial tonometry at rest, IHG at 30% maximal force, and PEMI in 30 (15/group) postmenopausal women with low (≤ 4.5%) and normal (≥ 5.5%) FMD. Hemodynamic responses were analyzed as the change (Δ) from rest to the last minute of IHG and PEMI. Brachial and aortic systolic BP (SBP) responses to IHG were higher in the low vs normal FMD group (P < 0.05). Aortic SBP (Δ20 ± 8 vs Δ11 ± 7mmHg), pulse pressure (PP) (Δ12 ± 8 vs Δ6 ± 4mmHg), augmented pressure (AP) (Δ5 ± 3 vs Δ2 ± 2mmHg), and Pb (Δ6 ± 4 vs Δ3 ± 2mmHg) responses to PEMI were greater (P < 0.05) in women with low vs. normal FMD. FMD was negatively correlated with aortic SBP, PP, AP, and Pb (P < 0.05) responses to PEMI. cfPWV was not correlated with responses to PEMI. Endothelial dysfunction relates to augmented aortic pulsatile load during metaboreflex activation, which may increase cardiovascular risk in postmenopausal women.

Selective load control of lumbar muscles in robot-assisted isometric lumbar stabilization exercise

Lumbar stabilization exercises are commonly employed in the rehabilitation of patients with low back pain. However, many patients discontinue these exercises, generally calisthenics using various postures or tools, due to the difficulty of providing an appropriate exercise load intensity. This challenge results in an inability to apply the desired strength to the target lumbar muscles and sometimes leads to an excessive load on unintended areas during calisthenics. Consequently, a method that enables patients to exercise continuously and progressively recover is required, specifically one that can target the lumbar muscles with a desired load. To address this issue, we propose a rehabilitation assistive device that quantitatively controls the lumbar spine load. In isometric lumbar stabilization exercises, our method involves precise compensation for gravity. The device, equipped with a series elastic actuator, is positioned beneath the patient in a lying posture. It applies an assistive force in the direction opposite to gravity, enabling precise control of the load on the lumbar region and reducing the vertical load on the spine. To validate the effectiveness of our proposed method, we conducted experiments with 20 healthy subjects across three exercises and analyzed the electromyography signal using nonparametric statistical methods. Our objective was to determine whether the load on the target lumbar muscles could be precisely and gradually controlled. The statistical results indicate that exercises performed using the proposed device produce statistically significant load changes in the target lumbar muscles.

STRESS URINARY INCONTINENCE: A TEN YEARS SYSTEMATIC REVIEW

Introduction: Stress urinary incontinence (SUI) and pelvic organ prolapse (POP) affect a substantial percentage of women, significantly impacting their quality of life. This review explores the prevalence, definitions, and pathophysiology of SUI, POP, and associated urinary incontinence, emphasizing the need for medical attention and offering insights into current treatment trends over the past 5 years. Methods: The researchers in this study followed the 2020 Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines to ensure that their work met the required standards. This was done to ensure the precision and reliability of the conclusions derived from the research. Result: Our search produced 21 results. After looking at the titles and summaries, we found 9 papers that fit our criteria. At first, we excluded several articles because they were written in review style. But after reading the full papers carefully, we included five papers in our final analysis. These papers included a retrospective observational study, prospective study, and randomized control trial. Conclusion: In this decade-long systematic review on stress urinary incontinence (SUI), notable findings include a 2.2 prevalence of SUI operations post-hysterectomy, persistent links between vaginal hysterectomy (VH) and SUI operations, and significant associations with preceding pelvic organ prolapse (POP), vaginal deliveries, laparoscopic hysterectomy (LH), and urinary incontinence (UI) visits. Combining pelvic floor muscle (PFM) strengthening with hip synergic muscle exercises improves daily urine loss frequency, while modifiable risk factors such as achieving an ideal body weight and preventing traumatic vaginal delivery are identified for SUI prevention. Cost analysis indicates that savings from avoiding unnecessary surgical treatments through urodynamic investigations (UDIs) in uncomplicated patients cover associated expenses, emphasizing the need to consider potential legal actions in a comprehensive cost assessment of negative externalities

Acetaminophen influences musculoskeletal signaling but not adaptations to endurance exercise training.

Acetaminophen (ACE) is a widely used analgesic and antipyretic drug with various applications, from pain relief to fever reduction. Recent studies have reported equivocal effects of habitual ACE intake on exercise performance, muscle growth, and risks to bone health. Thus, this study aimed to assess the impact of a 6-week, low-dose ACE regimen on muscle and bone adaptations in exercising and non-exercising rats. Nine-week-old Wistar rats (n = 40) were randomized to an exercise or control (no exercise) condition with ACE or without (placebo). For the exercise condition, rats ran 5 days per week for 6 weeks at a 5% incline for 2 min at 15 cm/s, 2 min at 20 cm/s, and 26 min at 25 cm/s. A human equivalent dose of ACE was administered (379 mg/kg body weight) in drinking water and adjusted each week based on body weight. Food, water intake, and body weight were measured daily. At the beginning of week 6, animals in the exercise group completed a maximal treadmill test. At the end of week 6, rats were euthanized, and muscle cross-sectional area (CSA), fiber type, and signaling pathways were measured. Additionally, three-point bending and microcomputer tomography were measured in the femur. Follow-up experiments in human primary muscle cells were used to explore supra-physiological effects of ACE. Data were analyzed using a two-way ANOVA for treatment (ACE or placebo) and condition (exercise or non-exercise) for all animal outcomes. Data for cell culture experiments were analyzed via ANOVA. If omnibus significance was found in either ANOVA, a post hoc analysis was completed, and a Tukey's adjustment was used. ACE did not alter body weight, water intake, food intake, or treadmill performance (p > .05). There was a treatment-by-condition effect for Young's Modulus where placebo exercise was significantly lower than placebo control (p < .05). There was no treatment by condition effects for microCT measures, muscle CSA, fiber type, or mRNA expression. Phosphorylated-AMPK was significantly increased with exercise (p < .05) and this was attenuated with ACE treatment. Furthermore, phospho-4EBP1 was depressed in the exercise group compared to the control (p < .05) and increased in the ACE control and ACE exercise group compared to placebo exercise (p < .05). A low dose of ACE did not influence chronic musculoskeletal adaptations in exercising rodents but acutely attenuated AMPK phosphorylation and 4EBP1 dephosphorylation post-exercise.

Menthol alleviates post-race elevations in muscle soreness and metabolic and respiratory stress during running.

We evaluated (1) whether participating in middle- and long-distance running races augments muscle soreness, oxygen cost, respiration, and exercise exertion during subsequent running, and (2) if post-race menthol application alleviates these responses in long-distance runners. Eleven long-distance runners completed a 1500-m race on day 1 and a 3000-m race on day 2. On day 3 (post-race day), either a 4% menthol solution (Post-race menthol) or a placebo solution (Post-race placebo) serving as a vehicle control, was applied to their lower leg skin, and their perceptual and physiological responses were evaluated. The identical assessment with the placebo solution was also conducted without race participation (No-race placebo). The integrated muscle soreness index increased in the Post-race placebo compared to the No-race placebo (P < 0.001), but this response was absent in the Post-race menthol (P = 0.058). Oxygen uptake during treadmill running tended to be higher (4.3%) in the Post-race placebo vs. No-race placebo (P = 0.074). Oxygen uptake was 5.4% lower in the Post-race menthol compared to the Post-race placebo (P = 0.018). Minute ventilation during treadmill running was 6.7-7.6% higher in the Post-race placebo compared to No-race placebo, whereas it was 6.6-9.0% lower in the Post-race menthol vs. Post-race placebo (all P ≤ 0.001). The rate of perceived exertion was 7.0% lower in the Post-race menthol vs. Post-race placebo (P = 0.007). Middle- and long-distance races can subsequently elevate muscle soreness and induce respiratory and metabolic stress, but post-race menthol application to the lower legs can mitigate these responses and reduce exercise exertion in long-distance runners.