The prevalence patterns and risk factor profiles of poor muscle health and its associated components in multiethnic older Asians: The PIONEER study.

BACKGROUND: We aim to determine the multiethnic patterns of the prevalence and associated factors of poor muscle health and its associated components in older Chinese, Malays, and Indian Asian adults. METHODS: We included 2199 participants (mean age ± SD: 72.9 ± 8.3 years; 54.3% female) from the baseline assessment of the Population Health and Eye Disease Profile in Elderly Singaporeans (PIONEER; 2017-2022) cohort study. Poor muscle health was defined as the presence of either low muscle mass (DEXA), or low muscle strength (handgrip strength), or low physical performance (gait speed). Its components include poor muscle function (low muscle strength and/or low physical performance without low muscle mass), pre-sarcopenia (low muscle mass only), and any sarcopenia (low muscle mass with low muscle strength and/or low physical performance). Sociodemographic, clinical, and lifestyle factors were assessed using biochemistry, clinical tests, and validated questionnaires. Regression models were utilized to evaluate the independent risk factors of poor muscle health and its components. RESULTS: The national census-adjusted prevalence of poor muscle health (88%) was similar across the three ethnic groups. However, Chinese individuals had higher prevalence of pre-sarcopenia and any sarcopenia, and a lower prevalence of poor muscle function compared with Indians or Malays. We observed ethnic differences in modifiable risk factors (low physical activity, diabetes, osteoporosis, and obesity) of poor muscle health and its components. Although obesity was protective of pre-sarcopenia (RRR = 0.19, 95% CI: 0.11, 0.36) and any sarcopenia (RRR = 0.29, 95% CI: 0.18, 0.47) in the overall population and across ethnic groups, it was associated with 1.7 times (95% CI: 1.07, 2.67) the likelihood of poor muscle function in the entire population. CONCLUSIONS: Almost 90% of community dwelling Singaporean aged ≥60 years have poor muscle health across the three ethnic groups with ethnic disparities in modifiable risk factors, highlighting an urgent need for community-wide targeted interventions to promote muscle health.

Reduced exercise capacity occurs before intrinsic skeletal muscle dysfunction in experimental rat models of pulmonary hypertension.

Reduced exercise capacity in pulmonary hypertension (PH) significantly impacts quality of life. However, the cause of reduced exercise capacity in PH remains unclear. The objective of this study was to investigate whether intrinsic skeletal muscle changes are causative in reduced exercise capacity in PH using preclinical PH rat models with different PH severity. PH was induced in adult Sprague-Dawley (SD) or Fischer (CDF) rats with one dose of SU5416 (20 mg/kg) injection, followed by 3 weeks of hypoxia and additional 0-4 weeks of normoxia exposure. Control s rats were injected with vehicle and housed in normoxia. Echocardiography was performed to assess cardiac function. Exercise capacity was assessed by VO2 max. Skeletal muscle structural changes (atrophy, fiber type switching, and capillary density), mitochondrial function, isometric force, and fatigue profile were assessed. In SD rats, right ventricular systolic dysfunction is associated with reduced exercise capacity in PH rats at 7-week timepoint in comparison to control rats, while no changes were observed in skeletal muscle structure, mitochondrial function, isometric force, or fatigue profile. CDF rats at 4-week timepoint developed a more severe PH and, in addition to right ventricular dysfunction, the reduced exercise capacity in these rats is associated with skeletal muscle atrophy; however, mitochondrial function, isometric force, and fatigue profile in skeletal muscle remain unchanged. Our data suggest that cardiopulmonary impairments in PH are the primary cause of reduced exercise capacity, which occurs before intrinsic skeletal muscle dysfunction.

Physiotherapy for continence and muscle function in prostatectomy: a randomised controlled trial.

OBJECTIVE: To assess the effectiveness of pre- and postoperative supervised pelvic floor muscle training (PFMT) on the recovery of continence and pelvic floor muscle (PFM) function after robot-assisted laparoscopic radical prostatectomy (RARP). PATIENTS AND METHODS: We carried out a single-blind randomised controlled trial involving 54 male patients scheduled to undergo RARP. The intervention group started supervised PFMT 2 months before RARP and continued for 12 months after surgery with a physiotherapist. The control group was given verbal instructions, a brochure about PFMT, and lifestyle advice. The primary outcome was 24-h pad weight (g) at 3 months after RARP. The secondary outcomes were continence status (assessed by pad use), PFM function, and the Expanded Prostate Cancer Index Composite (EPIC) score. RESULTS: Patients who participated in supervised PFMT showed significantly improved postoperative urinary incontinence (UI) compared with the control group (5.0 [0.0-908.0] g vs 21.0 [0.0-750.0] g; effect size: 0.34, P = 0.022) at 3 months after RARP based on 24-h pad weight. A significant improvement was seen in the intervention compared with the control group (65.2% continence [no pad use] vs 31.6% continence, respectively) at 12 months after surgery (effect size: 0.34, P = 0.030). Peak pressure during a maximum voluntary contraction was higher in the intervention group immediately after catheter removal and at 6 months, and a longer duration of sustained contraction was found in the intervention group compared with the control group. We were unable to demonstrate a difference between groups in EPIC scores. CONCLUSION: Supervised PFMT can improve postoperative UI and PFM function after RARP. Further studies are needed to confirm whether intra-anal pressure reflects PFM function and affects continence status in UI in men who have undergone RARP.

PGC-1α participates in regulating mitochondrial function in aged sarcopenia through effects on the Sestrin2-mediated mTORC1 pathway.

BACKGROUND: Mitochondrial dysregulation in skeletal myocytes is considered a major factor in aged sarcopenia. In this study, we aimed to study the effects of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) on Sestrin2-mediated mechanistic target of rapamycin complex 1 (mTORC1) in aged skeletal muscles. METHODS: C2C12 myoblasts were stimulated by 50 µM 7ß-hydroxycholesterol (7ß-OHC) to observe the changes of DNA damage, mitochondrial membrane potential (Δψm), mitochondrial ROS and PGC-1α protein. The PGC-1α silence in the C2C12 cells was established by siRNA transfection. The levels of DNA damage, Δψm, mitochondrial ROS, Sestrin2 and p-S6K1/S6K1 proteins were observed after the PGC-1α silence in the C2C12 cells. Recombinant Sestrin2 treatment was used to observe the changes of DNA damage, Δψm, mitochondrial ROS and p-S6K1/S6K1 protein in the 7ß-OHC-treated or PGC-1α siRNA-transfected C2C12 cells. Wild-type (WT) mice and muscle-specific PGC-1α conditional knockout (MKO) mice, including young and old, were used to analyse the effects of PGC-1α on muscle function and the levels of Sestrin2 and p-S6K1 in the white gastrocnemius muscles. Recombinant Sestrin2 was administrated to analyse its effects on muscle function in the old WT mice and old MKO mice. RESULTS: 7ß-OHC treatment induced DNA damage, mitochondrial dysfunction and decrease of PGC-1α protein in the C2C12 cells. PGC-1α silence also induced DNA damage and mitochondrial dysfunction in the C2C12 cells. Additionally, PGC-1α silence or 7ß-OHC treatment decreased the levels of Sestrin2 and p-S6K1/S6K1 protein in the C2C12 cells. Recombinant Sestrin2 treatment significantly improved the DNA damage and mitochondrial dysfunction in the 7ß-OHC-treated or PGC-1α siRNA-transfected C2C12 cells. At the same age, muscle-specific PGC-1α deficiency aggravated aged sarcopenia and decreased the levels of Sestrin2 and p-S6K1 in the white gastrocnemius muscles when compared to the WT mice. Recombinant Sestrin2 treatment improved muscle function and increased p-S6K1 levels in the old two genotypes. CONCLUSION: This research demonstrates that PGC-1α participates in regulating mitochondrial function in aged sarcopenia through effects on the Sestrin2-mediated mTORC1 pathway.

Test-retest reliability of lower limb muscle strength, jump and sprint performance tests in elite female team handball players.

PURPOSE: This study aimed to assess the reliability of lower limb muscle function (knee extensor/flexor peak torque, rate of torque development (RTD), impulse, and countermovement jump (CMJ) performance) and sprint performance (acceleration capacity). METHODS: CMJ performance was evaluated on a force plate. MVIC, RTD and impulse variables were investigated using a portable isometric dynamometer and sprint performance was assessed with dual-beam photocells in elite female athletes. RESULTS: CMJ test variables maximal vertical jump height, peak and mean power, concentric work, and body center of mass displacement demonstrated good-to-excellent test-retest correlations between Test 1 and Test 2 (ICC ≥ 0.70, CWw-s = 3.4-11.0%). Peak MVIC torque for the knee extensors and flexors demonstrated excellent test-retest correlations (both ICC = 0.84) along with CVw-s values of 6.8 and 6.0%, respectively. Late-phase (0-100 ms, 0-200 ms) RTD for the knee flexors demonstrated excellent test-retest correlations (ICC = 0.89-0.91, CVw-s = 4.8-8.5%). Sprint times at 10- and 20-m demonstrated excellent test-retest reproducibility (ICC = 0.83 and ICC = 0.90, respectively) with CVw-s values of 1.9 and 1.5%. For 5-m sprint times, test-retest reproducibility was good (ICC = 0.71) with CVw-s of 2.8%. Sprint testing performed while dribbling a handball improved (p < 0.05) from test to retest at 5-, 10- and 20-m. CONCLUSION: In conclusion, the force plate, the mobile isometric dynamometer, and dual-beam photocells provide reproducible tools for field-based testing of countermovement jump performance, knee extensor and flexor strength and sprint performance.

Effects of arthroscopic rotator cuff repair on isokinetic muscle function 6-months following surgery: influence of tear type, tear size and tendon retraction.

BACKGROUND: Rotator cuff tears are a common musculoskeletal condition which can lead to functional limitations and impairments in quality of life. The purpose of the present study was to investigate the effects of arthroscopic repair surgery on isokinetic muscle function before and 6-months after surgery. Additionally, the mediating effects of tear type, tear size and tendon retraction were examined. METHODS: Data from n = 67 patients (56 ± 9 years) with full-thickness rotator cuff tears were analyzed. Before and 6-months after surgery, isokinetic muscle function in external/internal rotation and abduction/adduction movements was assessed. Further, tear size, tear type (Collin classification) and tendon retraction (Patte classification) were analyzed using magnetic resonance imaging (MRI). RESULTS: After statistical analysis, a significant increase in limb symmetry index (LSI) of external (p < 0.001), internal rotation (p < 0.01), abduction (p < 0.001) and adduction (p < 0.001) were observed from pre- to post-surgery. The results revealed that tear size and tendon tear type significantly mediated the functional outcome, with no significant effect of tendon retraction. CONCLUSION: The present findings point towards the notion that the functional outcome following rotator cuff repair was significantly dependent on tear type and tear size but not tendon retraction. Patients with larger sized tears presented pronounced deficits following 6-months indicating that rehabilitation times need to be adjusted accordingly.

The Mood-Muscle Meta Bridge (Brain Muscle Axis).

Psychological well-being is essential for the maintenance of good metabolic health. Modern management of most chronic metabolic disorders rightly focusses on improving the health-related quality of life of persons living with disease. In this brief communication we describe the bidirectional association between muscle function and mood (psychological health), explore the various pathways that link these aspects of health, and underscore their clinical implications. This paper emphasizes the importance of maintaining good mental health through exercise and vice a versa.

Can pelvic floor muscle function before surgery determine the outcome of surgical treatment of stress urinary incontinence in women?

AIM: The study aimed to determine whether pelvic floor muscle (PFM) function before surgery may correlate with the success of surgical interventions for treating stress urinary incontinence (SUI). Our hypothesis was that addressing identified variables in preoperative rehabilitation could potentially improve surgical outcomes. METHODS: This prospective observational study was conducted at a single center and enrolled women qualified to mid-urethral tape insertion for SUI between 2020 and 2022. Digital palpation and manometry (Peritron™ 9300 V) were used to evaluate PFM function. The following parameters were acquired: vaginal resting pressure, vaginal pressure during maximal voluntary contraction (MVC), the area under the curve during a 10-second MVC, moreover the ability to perform correct PFM contraction, reflexive PFM contraction during cough and relaxation were assessed. All measurements were performed before the surgical treatment and during follow-up assessments at 1, 3, and 6 months postoperatively. The primary endpoint of the study was defined as objective cure, characterized by a negative cough stress test (CST), along with a subjective assessment based on the Urogenital Distress Inventory-6 (UDI-6) and Incontinence Impact Questionnaire-7 (IIQ-7). RESULTS: The study involved 57 eligible female participants, all of whom completed the 6-month follow-up. Objective cure was observed in 75.44% of cases, while subjective cure was reported in 33%. There was no association between PFM parameters and surgical outcomes. CONCLUSION: The success of surgical treatment of SUI 6 months postsurgery is not related to preoperative pelvic floor muscle function.

The effects of muscle starting length on work loop power output of isolated mouse soleus and extensor digitorum longus muscle.

Force-length (F-L) relationships derived from isometric activations may not directly apply to muscle force production during dynamic contractions. As such, different muscle starting lengths between isometric and dynamic conditions could be required to achieve maximal force and power. Therefore, this study examined effects of starting length (± 5-10% of length corresponding to maximal twitch force [L0]) on work loop (WL) power output (PO), across a range of cycle frequencies, of soleus and extensor digitorum longus muscle (EDL; N=8-10) isolated from ∼8-week-old C57 mice. Furthermore, passive work was examined at a fixed cycle frequency to determine association of passive work and active net work. Starting length affected maximal WL PO of soleus and EDL across evaluated cycle frequencies (P<0.030, ηp2 >0.494). For soleus, PO produced at -5% L0 was greater than most starting lengths (P<0.015, d>0.6), except vs. -10% L0 (P=0.135, d<0.4). However, PO produced at -10%L0 vs. L0 did not differ (P=0.138, d=0.35-0.49), indicating -5%L0 is optimal for maximal soleus WL PO. For EDL, WL PO produced at -10%L0 was lower than most starting lengths (P<0.032, d>1.08), except vs. -5%L0 (P=0.124, d<0.97). PO produced at other starting lengths did not differ (P>0.163, d<1.04). For soleus, higher passive work was associated with reduced PO (Spearman's r=0.709, P<0.001), but no relationship was observed between passive work and PO of EDL (Pearson's r=0.191, r2=0.04, P=0.184). This study suggests that starting length should be optimised for both static and dynamic contractions and confirms that the F-L curve during dynamic contractions is muscle specific.

Muscle activity and rehabilitation in spinal stenosis (MARSS) after conservative therapy and surgical decompression with or without fusion: Protocol for a partially randomized patient preference trial on rehabilitation timing.

Background: Patients affected by lumbar spinal stenosis (LSS) suffer from a multifactorial degeneration of the lumbar spine resulting in narrowing of the neuroforamina and spinal canal, leading to various functional limitations. It remains unclear whether LSS patients after surgery would benefit from early post-operative rehabilitation, or if a delayed rehabilitation would be more advantageous. The purpose of this partially randomized patient preference trial is to evaluate the impact of post-operative rehabilitation timing as well as surgical intervention type on psychometric properties and functional outcomes in patients with LSS. Methods: Data for this patient preference trial are collected before and after surgical (decompression only or decompression and fusion) and rehabilitative interventions as well as six, 12 and 24 months after completing rehabilitation. The study participants are patients diagnosed with LSS who are at least 18 years old. After a medical check-up, participants will complete patient-reported outcome measures (PAREMO-20, SIBAR, FREM-8, SF-12, SFI, ODI) and different functional assessments (functional reach test, loaded reach test, handgrip strength, standing balance control, 6-min walk test). Ethics and dissemination: The results of this study will be published through peer-reviewed publications and scientific contributions at national and international conferences. This research has been approved by the Institutional Review Board of Martin Luther University Halle-Wittenberg (reference number: 2022-128).

Effects of proprioceptive neuromuscular facilitation and both sides up ball exercise on pain level, range of motion, muscle function after total knee arthroplasty.

Knee osteoarthritis (OA) is a degenerative joint disease caused tearing and progressive wear of articular cartilage, and total knee arthroplasty (TKA) is recommended to patients with OA. The purpose of this study was to investigate the effect of proprioceptive neuromuscular facilitation (PNF) and both sides up ball (BOSU) exercises on pain, range of motion (ROM), and muscle function in patients following TKA. Ten participants who have limitation of the knee joint from TKA were divided into two groups: the continuous passive motion (CPM)+PNF exercise group (n=5) and the CPM+BOUS exercise group (n=5). Exercise rehabilitation program consisted of PNF and BOSU exercises, and both exercises were performed twice a day for 2 weeks. To examine effect of exercise rehabilitation, visual analogue scale (VAS), sit and reach flexibility, knee ROM, and Timed Up and Go test (TUG) were measured before and after exercise intervention. A two-way repeated analysis of variance was used to confirm the main effect. If there was a significant interaction effect, an independent t-test between groups or a paired t-test between times was applied. VAS, sit and reach flexibility, knee ROM and TUG did not show interaction between the PNF and BOSU exercise groups, but all measured variables showed significant differences over time. Present findings provide information that PNF and BOSU exercise rehabilitation after TKA might be an important part of ensuring successful surgical outcomes as they have a positive impact on reducing pain, increasing ROM, improving muscle strength, and enhancing daily life movements.

Optimization of mHealth behavioral interventions for patients with chronic lymphocytic leukemia: the HEALTH4CLL study.

PURPOSE: This pilot study of a diet and physical activity intervention (HEALTH4CLL) was conducted to reduce fatigue and improve physical function (PF) in patients with chronic lymphocytic leukemia (CLL). METHODS: The HEALTH4CLL study used a randomized factorial design based on the multiphase optimization strategy (MOST). Patients received diet, exercise, and body weight management instructional materials plus a Fitbit and were randomized to undergo one of 16 combinations of 4 evidence-based mHealth intervention strategies over 16 weeks. Patients' fatigue, PF, health-related quality of life, behavior changes, and program satisfaction and retention were assessed. Paired t-tests were used to examine changes in outcomes from baseline to follow-up among patients. Factorial analysis of variance examined effective intervention components and their combinations regarding improvement in fatigue and PF scores. RESULTS: Among 31 patients, we observed significant improvements in fatigue (+ 11.8; t = 4.08, p = 0.001) and PF (+ 2.6; t = 2.75, p = 0.01) scores. The combination of resistance and aerobic exercise with daily self-monitoring was associated with improved fatigue scores (ß = 3.857, SE = 1.617, p = 0.027). Analysis of the individual components of the MOST design demonstrated greater improvement in the PF score with resistance plus aerobic exercise than with aerobic exercise alone (ß = 2.257, SE = 1.071, p = 0.048). CONCLUSIONS: Combined aerobic and resistance exercise and daily self-monitoring improved PF and reduced fatigue in patients with CLL. IMPLICATIONS FOR CANCER SURVIVORS: This pilot study supported the feasibility of a low-touch mHealth intervention for survivors of CLL and provided preliminary evidence that exercising, particularly resistance exercise, can improve their symptoms and quality of life.

Developmental changes in motor unit activity patterns: child-adult comparison using discrete motor unit analysis.

Using global surface electromyography (sEMG) and the sEMG threshold it has been suggested that children activate their type-II motor unit (MU) to a lesser extent compared with adults. However, when age-related differences in discrete MU activation are examined using sEMG decomposition this phenomenon is not observed. Furthermore, findings from these studies are inconsistent and conflicting. Therefore, the purpose of this study was to examine differences in discrete MU activation of the vastus lateralis (VL) between boys and men during moderate-intensity knee extensions. Seventeen boys and 20 men completed two laboratory sessions. Following a habituation session, maximal voluntary isometric knee extension (MVIC) torque was determined before completing trapezoidal contractions at 70% MVIC. sEMG of the VL was captured and mathematically decomposed into individual MU action potential trains. Motor unit action potential amplitude (MUAPamp), recruitment threshold (RT), and MU firing rates (MUFR) were calculated. We observed that MUAPamp-RT slope was steeper in men compared with boys (p < 0.05) even after accounting for fat thickness and quadriceps muscle depth. The mean MUFR and y-intercept of the MUFR-RT relationship were significantly (p < 0.001) lower in boys than in men. The slope of the MUFR-RT relationship tended to be steeper in men, but the differences did not reach statistical significance (p = 0.056). Overall, our results suggest that neural strategies used to produce torque are different among boys and men. Such differences may be related, in part, to boys' lower MUFR and lesser ability to activate their higher-threshold MUs. Although, other factors (e.g., muscle composition) likely also play a role.

Basketball Fatigue Impact on Kinematic Parameters and 3-Point Shooting Accuracy: Insights across Players' Positions and Cardiorespiratory Fitness Associations of High-Level Players.

This study investigated the impact of basketball-induced fatigue on 3-point jump shooting accuracy, the ball's entry angle (EA) into the hoop, shot release time (RT), their relationship with player positions in high-level basketball, and the correlation between cardiorespiratory fitness markers and potential shooting performance changes. Guards (n = 13), forwards (n = 13), and centers (n = 12) underwent physiological assessments. Sequentially, they performed 15 jump shots (PRE), a basketball exercise simulation (BEST) involving 24 × 30 s circuit activities, and a repeated shooting test (POST). The study design was double-blind. The results revealed significant differences (p ≤ 0.05) in RT, EA, and successful shots (SSs) between PRE and POST in each group. The percentage changes from PRE to POST conditions across guards, forwards, and centers were for RT: 25.34% [95%CI: 1.7-48.98], 19.73% [95%CI: -1.9-41.36], 14.95% [95%CI: -5.23-35.13]; for EA: -3.89% [95%CI: -14.82-7.04], -3.13% [95%CI: -12.9-6.64], -3.47% [95%CI: -14.19-7.25]; and for SS: -14.42% [95%CI: -36.5-7.66], -16.76% [95%CI: -40.81-7.29], -19.44% [95%CI: -46.7-7.82], respectively. Post-test differences (p ≤ 0.05) highlighted greater fatigue impact on RT, EA, and SS from guards to centers. Additionally, significant correlations (p ≤ 0.05) were found between the ventilatory threshold, mean HR during BEST, and changes in RT, EA, and SS. This study highlights the substantial impact of basketball-induced fatigue on 3-point shooting parameters across player positions and the interplay with cardiorespiratory factors post-fatigue. Tailored training, considering heart rate, is crucial to optimizing shooting performance.

Association of inflammatory markers with muscle and cognitive function in early and late-aging older adults.

OBJECTIVES: Age-related loss in muscle and cognitive function is common in older adults. Numerous studies have suggested that inflammation contributes to the decline in physical performance and increased frailty in older adults. We sought to investigate the relationship of inflammatory markers, including CRP, IL-6, IL-10, TNF-α, TNFR1, and TNFR2, with muscle and cognitive function in frail early-aging and non-frail late-aging older adults. DESIGN: Secondary analysis of a cross-sectional study. SETTINGS AND PARTICIPANTS: Two hundred community-dwelling older men and women were included. They had been recruited in two groups based on age and functional status: 100 early-agers (age 65-75, who had poor functional status, and more co-morbidities) and 100 late-agers (older than 75 years, who were healthier and had better functional status). MEASUREMENTS: We assessed CRP, IL-6, IL-10, TNF-α, TNFR1, TNFR2, grip strength, Short Physical Performance Battery (SPPB) score, and cognitive function. We used correlation coefficients, partial correlations, and regression modeling adjusted for age, BMI, gender, and exercise frequency. RESULTS: The mean age in the two groups were 70.4 and 83.2, respectively. In regression models adjusting for age, BMI, gender and exercise frequency, early-agers demonstrated significant associations between inflammatory markers and outcomes. Each mg/dl of CRP was associated with (regression coefficient ± standard error) -0.6 ± 0.2 kg in grip strength (p = 0.0023). Similarly, each pg/mL of TNF-α was associated with -1.4 ± 0.7 (p = 0.0454), each 500 pg/mL of TNFR1 was associated with -1.9 ± 0.6 (p = 0.0008), and each 500 pg/mL of TNFR2 was associated with -0.5 ± 0.2 (p = 0.0098) in grip strength. Each 500 pg/mL of TNFR1 was associated with -0.4 ± 0.2 point in SPPB (p = 0.0207) and each pg/mL in IL-10 with 0.2 ± 0.1 point in MoCA (p = 0.0475). In late-agers, no significant correlation was found between any of the inflammatory markers and functional outcomes. CONCLUSION: In early-agers with frailty and more co-morbidities, the inflammatory markers CRP, TNF-α, TNFR1, and TNFR2 were associated with grip strength, TNFR1 was correlated with physical performance, and IL-10 was correlated with cognitive function. However, in healthier late-agers, no relationship was found between inflammatory markers and muscle or cognitive function. Our findings suggest presence of a relationship between inflammation and loss of muscle performance and cognitive function in frailer and sicker individuals, regardless of their chronological age.

Impact of preterm birth on muscle mass and function: a systematic review and meta-analysis.

Individuals born preterm present lower exercise capacity. Along with the cardiopulmonary responses and activity level, muscle strength is a key determinant of exercise capacity. This systematic review aimed to summarize the current knowledge on the impact of preterm birth on skeletal muscle mass and function across the lifespan. The databases PubMed, MEDLINE, EBM, Embase, CINAHL Plus, Global Index Medicus, and Google Scholar were searched using keywords and MeSH terms related to skeletal muscle, preterm birth, and low birth weight. Two independent reviewers undertook study selection, data extraction, and quality appraisal using Covidence review management. Data were pooled to estimate the prematurity effect on muscle mass and function using the R software. From 4378 studies retrieved, 132 were full-text reviewed and 25 met the inclusion/exclusion criteria. Five studies presented a low risk of bias, and 5 had a higher risk of bias due to a lack of adjustment for confounding factors and presenting incomplete outcomes. Meta-analyses of pooled data from homogenous studies indicated a significant reduction in muscle thickness and jump test (muscle power) in individuals born preterm versus full-term with standardized mean difference and confidence interval of - 0.58 (0.27, 0.89) and - 0.45 (0.21, 0.69), respectively.    Conclusion: Overall, this systematic review summarizing the existing literature on the impact of preterm birth on skeletal muscle indicates emerging evidence that individuals born preterm, display alteration in the development of their skeletal muscle mass and function. This work also highlights a clear knowledge gap in understanding the effect of preterm birth on skeletal muscle development. What is Known: • Preterm birth, which occurs at a critical time of skeletal muscle development and maturation, impairs the development of different organs and tissues leading to a higher risk of comorbidities such as cardiovascular diseases. • Preterm birth is associated with reduced exercise capacity. What is New: • Individuals born preterm display alterations in muscle mass and function compared to individuals born at term from infancy to adulthood. • There is a need to develop preventive or curative interventions to improve skeletal muscle health in preterm-born individuals.

Trunk Muscle Function and Core Stability in Women Who Had Muscle-Sparing Pedicled Transverse Rectus Abdominis Myocutaneous Flap Breast Reconstruction.

OBJECTIVE: The long-term effects of the unilateral muscle-sparing pedicled transverse rectus abdominis myocutaneous (TRAMmsp) flap procedure on trunk muscle performances and core stability were investigated in women with breast cancer. METHODS: Forty women (mean age = 42.6 years) who had received breast reconstruction with the unilateral TRAMmsp flap procedure no less than 6 months earlier (mean = 10.3 [SD = 4.9] months) (TRAM group) participated, and 30 women who were healthy and matched for age (mean age = 41.2 years) served as controls (control group). Their abdominal and back muscle strength was assessed using the curl-up and prone extension tests, respectively, and their static abdominal muscle endurance and back extensor endurance were assessed using the sit-up endurance test in the crook-lying position and the Biering-Sørensen test, respectively. Core stability strength was assessed using a 4-level limb-lowering test (abdominal muscle test) and core stability endurance was assessed while lying supine with both flexed legs 1 inch off the mat while keeping the pelvis in a neutral position with a pressure biofeedback unit. RESULTS: Compared with the control group, trunk muscles of the TRAM group were weaker, showing less endurance, as were their core stability strength and endurance. Static trunk muscle endurances and trunk flexion strength were associated with core stability in both groups. CONCLUSIONS: Women exhibit trunk flexor and extensor weakness along with poor endurance and impaired core stability even after an average of 10 months from receiving the TRAMmsp flap procedure. Immobilization after surgery, with possible systemic inflammatory effects from surgery and chemotherapy, might have further contributed to the generalized weakness subsequent to the partial harvesting of the rectus abdominis. IMPACT: Women after breast reconstruction with the TRAMmsp flap procedure show long-lasting deficits of strength and endurance in abdominal muscles, back extensors, and core stability. Proactive measures including early detection and evaluation of impairments as well as timely intervention targeting these clients are important to minimize the dysfunction and support their return to community participation.

Do pelvic floor muscle function parameters differ in women according to continence status? A systematic review.

BACKGROUND: Current literature highlights the difficulty in identifying which pelvic floor muscle (PFM) functions are correlated with urinary incontinence (UI). AIM: In this study, we compared parameters of PFM function (strength, endurance, tone, control, reaction, and/or coordination) according to continence status in women (presence or absence, type and/or severity of urinary incontinence). EVIDENCE ACQUISITION: A systematic review was conducted following the 2020 PRISMA guidelines. Three databases (Pubmed, Web of Science, and LiSSa) were searched from inception to December 31, 2021. Assessment of risk of bias was performed using the Joanna Briggs Institute critical appraisal checklist. EVIDENCE SYNTHESIS: The initial research yielded 4733 studies. Forty-two studies met the inclusion criteria, including 4015 participants. No statistical association was found between PFM function and the presence or absence of UI, the different type of UI or the different levels of severity of UI. The heterogeneity in methodologies and analyzes of the results only with the P-value are important limitations of this review. CONCLUSION: It appears that muscle function is not always associated with presence or absence of UI. No association is found between PFM function and type or severity of UI. These results reinforce the need to carry out a bio-psycho-social evaluation of UI that does not only focus on PFM functions. As such, the results reported herein can be considered a resource for more specific research.

Corrigendum: Non-invasive methods to assess muscle function in dogs: a scoping review.

[This corrects the article DOI: 10.3389/fvets.2023.1116854.].

Exploring the impact of short daily haemodialysis on muscle strength and bone health in end-stage kidney disease patients.

BACKGROUND: Short-daily haemodialysis (SDH) has been strongly recommended over conventional haemodialysis (CHD) for end-stage kidney disease patients, though few studies have directly compared the effects of these two haemodialysis (HD) modalities on clinical variables related to patient's health. METHODS: We conducted a cross-sectional study in individuals undergoing HD, comparing epidemiological, clinical, metabolic, inflammatory, anthropometric, bone health/metabolism, and skeletal muscle function according to dialysis modality. One-hundred seventy-eight patients (20.8% females, 62 ± 2.5 years old), were analysed in this study, 86 (48%) of whom were undergoing CHD versus 92 (51%) who were undergoing SDH. RESULTS: SDH patients had significantly higher serum albumin levels (3.93 vs. 3.66 g/dL, P < 0.0001) and higher Kt/v (2.6 vs. 2.38, P < 0.0001). SDH group presented a significantly lower number of erythropoietin-stimulating agents compared with CHD group (percentage: 53.3 vs. 83.7%, P < 0.0001) and had lower levels of serum phosphate (4.9 vs. 5.3 mg/dL, P = 0.004) and parathyroid hormone (PTH) (398.4 vs. 480.4 pg/mL, P < 0.001) compared with CHD patients. In terms of bone health and metabolism, SDH patients had significantly higher total BMD, femur BMD, lumbar BMD, and femoral neck BMD compared with CHD patients (all P < 0.05). SDH patients also had lower anti-osteogenic and inflammatory biomarkers, including FGF23, sclerostin, TNF, IL-18, IL-17a, and C-reactive peptide (all P < 0.05). CHD modality was demonstrated to be a risk factor for low BMD (odds ratio: 4.02; 95% CI: 1.59-10.2, P = 0.003). In terms of skeletal muscle function, SDH patients had significantly higher 6-minute walking test (444.6 vs. 424.9 m, P = 0.04) and higher fat-free mass (52.3 vs. 51.68 kg, P = 0.02) compared with CHD patients. Higher fat-free mass and handgrip strength were associated with a 34% and 23% lower risk of low BMD, respectively. SDH patients had lower levels of the uremic toxin asymmetric dimethyl-l-arginine (ADMA) (1.8 vs. 2.07 µM, P = 0.002) and fasting blood glucose (132.6 vs. 141.7 mg/dL, P < 0.02) than CHD group. SDH patients also displayed higher levels of haemoglobin when compared with CHD group (11.9 vs. 10.2 g/dL, P < 0.0001). CONCLUSIONS: The present study improves our understanding of the relationship between dialysis modality and clinical variables that may influence HD patient's health. Grip strength and lean mass were positively correlated with bone mineral density in HD patients regardless of dialysis modality. SDH was associated with better bone mineral density, inflammatory profile, and skeletal muscle function when compared with CHD patients. These findings provide more evidence of the clinical benefits of SDH that should be explored in greater detail.