Inspiratory Muscle Training in Phase 1 and 2 Postoperative Cardiac Rehabilitation Following Coronary Artery Bypass Graft Surgery: Systematic Review with Meta-Analysis.

OBJECTIVE: This study aimed to determine the effects of inspiratory muscle training (IMT) on exercise capacity, respiratory muscle strength, length of hospital stay (LOS), and quality of life (QOL) following coronary artery bypass graft surgery. METHODS: The search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Cochrane Handbook and included the databases MEDLINE, EMBASE, CINAHL, Scopus, and CENTRAL. The review included randomized controlled trials utilizing IMT during phase 1 or 2 postoperative cardiac rehabilitation (PoCR) versus alternative treatment (active or passive control) in patients following coronary artery bypass graft surgery. RESULTS: Fifteen studies were included (11 phase 1 studies, 4 phase 2 studies) with no reported adverse events. In phase 1 PoCR, IMT reduced the LOS (-1.02 days; 95% CI = -2.00 to -0.03) and increased exercise capacity (6-minute walk distance [6MWD]).(+75.46 m; 95% CI = 52.34 to 98.57), and maximal inspiratory pressure (MIP) (10.46 cm H2O; 95% CI = 2.83 to 18.10), but had no effect on maximal expiratory pressure. In phase 2 PoCR, IMT increased 6MWD (45.84 m; 95% CI = 10.89 to 80.80), MIP (-23.19 cm H2O; 95% CI = -31.31 to -15), maximal expiratory pressure (20.18 cm H2O; 95% CI = 9.60 to 30.76), and QOL (-11.17; 95% CI = -17.98 to -4.36), with no effect on peak oxygen uptake. There was a high risk of bias for MIP (75% of the phase 1 studies) and 6MWT (1 of 4 phase 2 studies). The quality of the evidence ranged from very low to moderate. CONCLUSIONS: IMT significantly improves exercise capacity, respiratory muscle strength, LOS, and QOL in phase 1 and 2 PoCR. IMPACT: IMT may benefit patients during phase 1 and 2 of PoCR, considering the safety, low cost, and potential benefits.

Investigating the Effects of Diet-Induced Prediabetes on Skeletal Muscle Strength in Male Sprague Dawley Rats.

Type 2 diabetes mellitus, a condition preceded by prediabetes, is documented to compromise skeletal muscle health, consequently affecting skeletal muscle structure, strength, and glucose homeostasis. A disturbance in skeletal muscle functional capacity has been demonstrated to induce insulin resistance and hyperglycemia. However, the modifications in skeletal muscle function in the prediabetic state are not well elucidated. Hence, this study investigated the effects of diet-induced prediabetes on skeletal muscle strength in a prediabetic model. Male Sprague Dawley rats were randomly assigned to one of the two groups (n = 6 per group; six prediabetic (PD) and six non-pre-diabetic (NPD)). The PD group (n = 6) was induced with prediabetes for 20 weeks. The diet that was used to induce prediabetes consisted of fats (30% Kcal/g), proteins (15% Kcal/g), and carbohydrates (55% Kcal/g). In addition to the diet, the experimental animals (n = 6) were supplied with drinking water that was supplemented with 15% fructose. The control group (n = 6) was allowed access to normal rat chow, consisting of 35% carbohydrates, 30% protein, 15% fats, and 20% other components, as well as ordinary tap water. At the end of week 20, the experimental animals were diagnosed with prediabetes using the American Diabetes Association (ADA) prediabetes impaired fasting blood glucose criteria (5.6-6.9 mmol/L). Upon prediabetes diagnosis, the animals were subjected to a four-limb grip strength test to assess skeletal muscle strength at week 20. After the grip strength test was conducted, the animals were euthanized for blood and tissue collection to analyze glycated hemoglobin (HbA1c), plasma insulin, and insulin resistance using the homeostatic model of insulin resistance (HOMA-IR) index and malondialdehyde (MDA) concentration. Correlation analysis was performed to examine the associations of skeletal muscle strength with HOMA-IR, plasma glucose, HbA1c, and MDA concentration. The results demonstrated increased HbA1c, FBG, insulin, HOMA-IR, and MDA concentrations in the PD group compared to the NPD group. Grip strength was reduced in the PD group compared to the NPD group. Grip strength was negatively correlated with HbA1c, plasma glucose, HOMA-IR, and MDA concentration in the PD group. These observations suggest that diet-induced prediabetes compromises muscle function, which may contribute to increased levels of sedentary behavior during prediabetes progression, and this may contribute to the development of hyperglycemia in T2DM.

Dietary Inflammatory Index and Dietary Diversity Score Associated with Sarcopenia and Its Components: Findings from a Nationwide Cross-Sectional Study.

Little is known about the independent and joint effects of the energy-adjusted dietary inflammatory index (E-DII) and dietary diversity score (DDS) on sarcopenia and its components (low muscle mass, low muscle strength, and low physical performance). A total of 155,669 UK Biobank participants with ≥1 (maximum 5) 24 h dietary assessments were included in this cross-sectional analysis. We used logistic regression models to investigate the associations of E-DII and DDS with sarcopenia and its three components. We further examined the joint effects of E-DII and DDS on sarcopenia and its components using additive and multiplicative interaction analyses. We observed that lower E-DII and higher DDS were associated with lower odds of sarcopenia and its components. There were significant joint associations of E-DII and DDS with sarcopenia and low physical performance (p-interaction < 0.05) on the multiplicative interactive scale. Our study suggests that lower dietary inflammatory potential and higher dietary diversity might be important protective factors against sarcopenia and its components. More cases of sarcopenia and low physical performance might be preventable by adherence to a more anti-inflammatory diet combined with a higher dietary diversity.

Ankle Muscle Strength and Gait Function After Dorsal Closing Wedge Calcaneal Osteotomy for Haglund Exostosis-Related Heel Pain.

BACKGROUND: Haglund exostosis-related heel pain may be surgically treated with dorsal closing wedge calcaneal osteotomy (DCWCO). Recent reports on this technique show good clinical and self-reported outcomes. However, uncertainty about functional consequences related to ankle muscle strength and gait function due to a shortened Achilles tendon lever arm exists. METHODS: Fifteen patients (15 feet) with Haglund exostosis-related heel pain were surgically treated with DCWCO and evaluated before and 1 year after surgery. Isometric plantar flexion and dorsiflexion strength was quantified for both the involved and the uninvolved limb. Gait analysis was performed at a self-selected walking speed using a 3D motion capture system including force plates. Self-reported outcomes (Foot Function Index and Global Treatment Outcome) were also assessed. RESULTS: Before surgery, as well as after surgery, plantar flexion strength of the involved limb was significantly lower compared to the uninvolved limb while dorsiflexion strength did not differ between limbs at both time points. Step length and time, ankle flexion angles, power generation, and propulsive impulses during gait did not differ between limbs both before and after surgery. Propulsive impulse and step length of the involved limb increased from pre- to postsurgery with an effect size of 1.04 and 0.48, respectively, revealing a general improvement in gait dynamics. Total Foot Function Index improved by 48% after surgery, and 80% of patients rated their surgery as "helped" or "helped a lot" (Global Treatment Outcome). CONCLUSION: In this relatively small cohort, we found that patients treated for Haglund exostosis-related heel pain with DCWCO surgery had minor interlimb differences in gait kinematics and kinetics and generally improved gait dynamics and self-reported function at 1-year follow-up. LEVEL OF EVIDENCE: Level II, observational prospective cohort study.

Effects of CICARE model combined with traditional Chinese medicine encapsulation on muscle strength and depression levels in hemiplegic patients with sequelae of cerebrovascular disease.

OBJECTIVE: To investigate the impact of the combination of CICARE (C - Connect, I - Introduce, C - Communicate, A - Ask, R - Respond, E - Exit) communication model and traditional Chinese medicine (TCM) poultice on muscle strength and depression levels in patients. METHODS: Patients were divided into three groups: basic treatment group, basic treatment + TCM poultice group, and combined treatment group. Conventional rehabilitation therapy, TCM poultice external application, and the combination of both with the CICARE communication model were applied in the respective groups. Muscle strength (AMA muscle strength grading scale), self-care abilities (Barthel Index), depression symptoms (Hamilton Depression Rating Scale), neurological deficit status (NIHSS score) and serum inflammatory factor levels were assessed at admission, 3 weeks, and 8 weeks of treatment. RESULTS: After 3 and 8 weeks of treatment, the combined treatment group had higher AMA muscle strength scores and improved Barthel Index scores compared to other groups (P < 0.05). Depressive symptoms also improved significantly in the combined treatment group, with lower HDRS scores at 3 and 8 weeks (P < 0.05). After 8 weeks, IL-1, IL-6, and hs-CRP levels decreased in all groups, with the combined treatment group showing the lowest levels (P < 0.05). NIHSS scores decreased significantly in all groups post-intervention, with the combined treatment group showing the greatest improvement (P < 0.05). CONCLUSION: The integration of CICARE communication model with TCM poultice shows notable benefits in enhancing muscle strength, daily living self-care abilities, reducing depression, neurological impairment, and inflammatory factors in post-stroke hemiplegia patients.

Stiffness Changes in Shoulder Muscles between Pitchers and Position Players after Throwing Overhead Using Shear Wave Elastography and Throwing Motion Analysis.

Objectives: The objective is to compare stiffness changes around the shoulder muscles between pitchers and position players after throwing overhead using shear wave elastography (SWE) in relation to throwing motion analysis and muscle strength. Methods: A total of 32 male college baseball players (12 pitchers and 20 position players) were observed throwing 20 times, and SWE was performed to evaluate 13 shoulder muscle items-tendons (supraspinatus, infraspinatus, subscapularis, and teres minor), muscles (supraspinatus, infraspinatus [transverse and oblique part], teres minor, lower trapezius, latissimus dorsi, and pectoralis minor), and capsules (posterior and posteroinferior). Motion analysis was used to assess elbow torque, forearm angle, forearm rotation speed, and maximum external rotation angle of the shoulder. Muscle strength was measured using a dynamometer for abduction, internal/external rotation of the shoulder at an abduction of 0°, internal/external rotation of the shoulder at an abduction of 90°, and internal/external rotation of shoulder at a flexion of 90°. Results: In the pitcher group, SWE values for the teres minor muscle and latissimus dorsi muscle increased significantly after throwing. In the position player group, SWE values for the teres minor muscle significantly increased, and SWE values of the pectoralis minor muscle decreased after throwing. In the pitcher group, positive correlations were found between the teres minor muscle and forearm rotation speed and between the latissimus dorsi muscle and forearm angle. No significant difference was found in muscle strength after throwing in any of the groups. Conclusions: Stiffness changes occurred after throwing and were related to the motion analysis, but the regions in which stiffness occurred varied between pitchers and position players.

Association of taurine intake with changes in physical fitness among community-dwelling middle-aged and older Japanese adults: an 8-year longitudinal study.

Introduction: Taurine has diverse valuable biological functions, including antioxidant activity and regulation of osmotic pressure. Maintaining physical fitness from middle age is important for healthy life expectancy. Although taurine administration improves muscle endurance and strength, its role in maintenance remains unclear. We aimed to clarify the longitudinal taurine intake association with fitness changes. Methods: Participants comprised men and women aged ≥40 years who participated in the third (2002-2004; Baseline) and seventh (2010-2012; Follow-up) waves of the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) and completed a 3-day dietary weights recording survey at baseline. A table of taurine content was prepared for 751 foods (including five food groups: Seaweed; Fish and shellfish; Meat; Eggs; and Milk and dairy products) from the Standard Tables of Food Composition in Japan (1,878 foods) 2010. Four physical fitness items (knee extension muscle strength, sit-and-reach, one-leg standing with eyes closed, and maximum walking speed) were measured at baseline and follow-up. We analyzed the association of taurine intake with physical fitness change, employing a general linear model (GLM) and trend tests for baseline taurine intake and follow-up fitness change. Adjustments included baseline variables: sex, age, height, weight, educational level, self-rated health, smoking status, depressive symptoms, and clinical history. Results: The estimated average daily taurine intake (standard deviation) was 207.5 (145.6) mg/day at the baseline. When examining the association with the four physical fitness parameters, higher taurine intake positively increased the change in knee extension muscle strength (T1; 0.1, T2; 0.8, T3; 1.1 (kgf) GLM, p < 0.05; p for trend <0.05) and reduced the decline in knee extension muscle strength in the subgroup analysis of participants aged ≥65 years (T1: -1.9, T2: -1.7, T3: -0.4 kgf; GLM p < 0.05, p for trend <0.05). No relationship was found between taurine intake and the remaining three fitness factors. Conclusion: Estimation of taurine intake showed that dietary taurine intake potentially contributes to the maintenance of knee extension muscle strength over 8 years among Japanese community-dwelling middle-aged and older individuals. This is the first study to investigate the association of dietary taurine intake with muscle strength.

Electrotherapy in stroke rehabilitation can improve lower limb muscle characteristics: a systematic review and meta-analysis.

PURPOSE: This review assesses the effect of electrotherapy (e.g. functional electrical stimulation (FES), motor and sensor therapeutic electrical stimulation (TES)) on muscle strength and skeletal muscle characteristics in individuals post-stroke compared to conventional or sham therapy. METHODS: A systematic literature search was conducted in MEDLINE, SCOPUS, and Web of Science, focusing on randomized controlled trials investigating the effect of electrotherapy. Data of interest was extracted from eligible studies, and risk of bias was assessed. RESULTS: In total, 23 studies (933 people post-stroke) were included, of which 17, which mainly focus on patients in a chronic stage of stroke recovery and the implementation of FES, were incorporated in the meta-analysis. A significant increase in muscle strength was found favoring electrotherapy over conventional therapy (SMD 0.63, 95% CI 0.34-0.91, I2 = 37%, p = 0.07) and over sham therapy (SMD 0.44, 95% CI 0.20-0.68, I2 = 38%, p = 0.08). Three studies investigated the effect on muscle thickness and found a significant increase in favor of electrostimulation when compared to conventional therapy (MD 0.11 cm, 95% CI 0.06-0.16, I2 = 0%, p = 0.50). CONCLUSION: Current evidence suggests electrotherapy in combination with physiotherapy has positive effects on lower limb muscle strength and skeletal muscle characteristics in patients recovering from stroke.

As stroke is known to cause long term disability, the implementation of strengthening interventions in rehabilitation becomes an indispensable part to optimize recovery.Peripheral electrical stimulation might be a useful intervention since it has the potential to repetitively activate the sensory-motor system via electrical pulses to nerves and muscles of the paretic limb.Results of the meta-analysis indicate a beneficial effect of electrotherapy on muscle strength when compared to conventional and sham therapy, and muscle thickness when compared to conventional therapy.

Feasibility of virtual reality and comparison of its effectiveness to biofeedback in children with Duchenne and Becker muscular dystrophies.

INTRODUCTION/AIMS: The utilization of virtual reality (VR) and biofeedback training, while effective in diverse populations, remains limited in the treatment of Duchenne and Becker muscular dystrophies (D/BMD). This study aimed to determine the feasibility of VR in children with D/BMD and compare the effectiveness of VR and biofeedback in children with D/BMD. METHODS: The study included 25 children with D/BMD. Eight children in the control group participated in a routine follow-up rehabilitation program, while the remaining children were randomly assigned to the VR (n = 9) and biofeedback (n = 8) groups for a 12-week intervention. The following evaluations were performed before, during (week 6), and after treatment: Muscle pain and cramps, laboratory studies, muscle strength, timed performance, function (Motor Function Measurement Scale-32, Vignos, and Brooke Scales), and balance (Pediatric Functional Reach Test and Balance Master System). Motivation for rehabilitation was determined. RESULTS: The median ages were 9.00 (VR), 8.75 (biofeedback), and 7.00 (control) years. The study found no significant differences between groups in pretreatment assessments for most measures, except for tandem step width (p < .05). VR and biofeedback interventions significantly improved various aspects (pain intensity, cramp frequency, cramp severity, muscle strength, timed performance, functional level, and balance) in children with D/BMD (p < .05), while the conventional rehabilitation program maintained patients' current status without any changes. The study found VR and biofeedback equally effective, with VR maintaining children's motivation for rehabilitation longer (p < .05). DISCUSSION: The study showed that both VR and biofeedback appear to be effective for rehabilitation this population, but additional, larger studies are needed.

Dysphagia After Total Laryngectomy: An Exploratory Study and Clinical Phase II Rehabilitation Trial with the Novel Swallowing Exercise Aid (SEA 2.0).

The aims of this exploratory study and clinical phase II trial were to assess the specific nature and extent of dysphagia in laryngectomized patients with self-reported dysphagia, and its rehabilitation potential using the novel Swallowing Exercise Aid (SEA 2.0). Twenty laryngectomized patients participated in a six-week exercise program with the SEA 2.0. Exercises consisted of Chin Tuck Against Resistance (CTAR), Jaw Opening Against Resistance (JOAR), and Effortful Swallow Against Resistance, conducted three times per day. Swallowing was assessed at baseline (T0), six (T1) and 14 (T2) weeks, consisting of patient-reported outcomes, BMI, videofluoroscopy, swallowing capacity, and muscle strength measurements. Dysphagia significantly impacts quality of life, with impaired swallowing speed and bolus propulsion as main reported issues. Subjective dysphagia parameters, swallowing capacity, and pharyngeal residue clearance were reduced, but BMI was normal. Muscle and tongue strength were within normal ranges. All participants managed to use the SEA 2.0. Adherence was 95%. At T1, subjective swallowing parameters (MDADI and EAT-10) showed clinically relevant improvements. Objectively, CTAR and JOAR strength increased with 27.4 and 20.1 Newton, respectively. Also, swallowing capacity (from 2.4 g/s to 3.8 g/s) and pharyngeal residue clearance improved. At T2, results were slightly lower than at T1, but still better than at baseline. Dysphagia in laryngectomized patients affects quality of life, but swallowing can be improved with a six-week rehabilitation program using the novel SEA 2.0. Adherence was excellent and several subjective and objective swallowing parameters improved.

Effectiveness of Virtual Reality-Based Interventions for Upper Limb Rehabilitation in Breast Cancer Patients: Systematic Review and Meta-Analysis.

Purpose: To investigate the effectiveness of virtual reality (VR)-based interventions for functional rehabilitation of the upper limb in breast cancer patients through a systematic review and meta-analysis. Methods: The PubMed, Cochrane, Web of Science, CINAHL, Scopus, CNKI, Wanfang, and VIP databases were systematically searched for relevant literature published from the establishment of the database to June 2023. Differences in the effectiveness of VR-based interventions and other intervention therapies were compared using random effects model meta-analysis and standard deviation (SMD). Results: Seven eligible articles were identified and included in the meta-analysis. The combined analysis found that VR-based interventions had a positive impact on patients' upper limb mobility in terms of flexion (SMD = 1.33, 95% confidence interval; CI [0.48-2.19], P = 0.002), abduction (SMD = 1.22, 95% CI [0.58-1.86], P = 0.0002), and external rotation (SMD = 0.94, 95% CI [0.48-1.40], P < 0.0001). In addition, VR-based interventions could significantly improve the postoperative pain of patients with breast cancer. However, in grip strength (SMD = 0.43, 95% CI [-3.05 to 3.92], P = 0.81), shoulder muscle strength in flexion strength (SMD = 0.05, 95% CI [-2.07 to 2.18], P = 0.96), abduction strength (SMD = -0.10, 95% CI [-1.32 to 1.12], P = 0.88), external rotation strength (SMD = 0.46, 95% CI [-1.96 to 2.88], P = 0.71), and lymphedema, VR was as effective as other intervention treatments. A subgroup analysis showed that patients younger than 55 years had more benefit with VR-based rehabilitation than with other interventions and showed improvements with the intervention within 2 weeks. The intervention effect of using auxiliary equipment such as robotic arms is better than VR exercise based solely on games. Conclusion: The results of meta-analysis show that the intervention measures based on VR have positive effects on the improvement of upper limb mobility and pain relief in breast cancer patients. However, considering the low quality of evidence and small sample size, more clinical studies should be conducted to improve the credibility of the results.

Is sarcopenia a real concern in ankylosing spondylitis? A systematic literature review.

PURPOSE: Sarcopenia is a condition defined as loss of muscle mass and strength, associated with poor functional performance and disability. Sarcopenia can be exacerbated or worsened in presence of inflammation, sedentary lifestyle and cytokine imbalance, thus it frequently occurs in people affected by rheumatic diseases. This systematic literature review aims to explore the association between sarcopenia and spondyloarthritis (SpA) and its most frequent manifestation, i.e. ankylosing spondylitis (AS). METHODS: The Scopus, PubMed, and Web of Science databases were searched for articles on muscle mass, muscle strength and axial SpA, from any date to November 2023. Only studies written in English were considered. The methodological quality of the studies included in the review was evaluated using the Newcastle-Ottawa Scales for observational studies and for case-control studies. RESULTS: 190 papers were retrieved from the searches, 14 of which met the inclusion criteria. Rather than diagnosis of sarcopenia, pre-sarcopenia or probable sarcopenia were frequent in people with AS, with a great reduction especially of muscle strength. The pre-sarcopenia status appears to be related to high AS disease activity, suggesting that chronic inflammation resulting in pain, less movement and decreased physical activity could play a role in the muscle heath of AS patients. CONCLUSIONS: Our review confirms the existence of an association between AS and loss of muscle strength-likely sarcopenia-already at a young age. Preventive and early strategies should be adopted to ensure successful aging for individuals with AS.

Why don't women engage in muscle strength exercise? An integrative review.

ISSUE ADDRESSED: Women are 'at-risk' population for failing to meet muscle strengthening guidelines. Health benefits specific to this exercise mode include maintenance of muscle mass, which is associated with reduced risk of chronic disease and falls. Of significance is the progressive decline in muscle strength exercise participation in women aged 35-54 in Australia. This period is critical for maintaining muscle strength as it establishes foundations for older women's engagement. This integrative review examined available evidence regarding factors influencing muscle strength exercise participation, specifically in women aged 35-54. METHODS: Seven databases were searched. Study inclusion criteria were: (1) peer reviewed, (2) English language, (3) sample populations of healthy female adults or general adult sample population differentiating females from males, (4) mean age between 35 and 54 years, (5) focused on muscle strength exercise and measured as the primary outcome factors of participation in muscle strength exercise. FINDINGS: Five of 1895 studies met inclusion criteria. Five key factors were associated with participation in muscle strength exercise of women aged 35-54 years: perceived time constraints; knowledge and education; modality and intensity; social support and behavioural strategies. CONCLUSIONS: Focused education on strength exercise and guidelines, plus initiatives and strategies that suit the needs of this cohort, are necessary to achieve health and wellbeing benefits. Responsive approaches by health professionals to these women's circumstances can potentially address current low participation levels. SO WHAT?: Creating conditions where health professionals respect a woman's exercise preferences can positively impact these women's musculoskeletal health into older age.

Association of Muscle Strength, Psychological Factors, and Central Sensitization With Movement-Evoked Pain in Patients With Nonspecific Chronic Low Back Pain: The BACKFIT Project.

BACKGROUND: People with chronic pain might evade certain movements to prevent their experience of pain. Movement-evoked pain (MEP) might induce lower functionality during daily activities. HYPOTHESIS: (1) MEP after physical fitness tests would vary depending on the main musculature involved in the test; (2) physical and psychological factors would be associated with MEP in patients with NSCLBP. STUDY DESIGN: Cross-sectional design. LEVEL OF EVIDENCE: Level 3. METHODS: A total of 104 (69 women) patients aged 51.0 ± 10.3 years with NSCLBP participated. MEP was measured with a visual analog scale (VAS) at baseline and immediately after performing each physical fitness test, that is, the Biering-Sørensen, prone bridging, handgrip, chair-stand, and 8-foot time-up-and-go tests, measuring back extensor, back flexor, upper- and lower-body muscle strength, and motor agility, respectively. Global muscle strength was calculated with normalized index (z-score) procedure. Depression, anxiety, pain catastrophizing, and central sensitization were assessed with the Beck Depression Inventory II, State Trait Anxiety Inventory I, Pain Catastrophizing Scale, and Central Sensitization Inventory (CSI), respectively. RESULTS: Patients showed greater pain after completion of the Biering-Sørensen (mean difference 95% CI, 0.02, 1.11), prone bridging (0.15, 1.21), lower pain after handgrip (-1.46, -0.52), and the 8-foot time-up-and-go (-1.43, 0.46) tests (all P ≤ 0.04). Lower global muscular strength (ß between -0.18 and -0.30), and greater pain catastrophizing (ß = 0.16), and CSI scoring (ß between 0.18 and 0.27) were associated with greater MEP (all P ≤ 0.04). CONCLUSION: Greater MEP was observed after tests measuring core musculature strength than after tests measuring distal (limbs) strength and agility. Greater MEP was overall associated with lower muscle strength, greater pain catastrophizing, and central sensitization. CLINICAL RELEVANCE: Fitness testing might be implemented as a complementary tool for the monitoring of NSCLBP in clinical settings.

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.

Relationships between muscle strength, lung function, and cognitive function in Chinese middle-aged and older adults: A study based on the China health and retirement longitudinal study (CHARLS).

OBJECTIVE: As the population ages, concerns about cognitive decline have become increasingly relevant in medical consultations. This study aims to analyze the interaction between muscle strength, lung function, and cognitive function in Chinese middle-aged and older adults, providing a theoretical basis for better prevention of cognitive decline. METHODS: This study used data from the China Health and Retirement Longitudinal Study (CHARLS) wave 3, including 13 716 participants aged 45 years or older. Cognitive function was assessed through two dimensions, resulting in a total score ranging from 0 to 31 points, with higher scores indicating better cognitive function. Muscle strength was measured using normalized grip strength and chair-standing time, while lung function was evaluated using peak expiratory flow (PEF). RESULTS: Total cognitive function scores exhibited significant correlations with grip strength, chair-standing time, and PEF. Muscle strength and lung function demonstrated significant associations with cognitive function, with lung function emerging as a notable mediating factor. This relationship persisted even after adjusting for potential confounding variables. Specifically, PEF played a substantial mediating role in linking grip strength to cognitive function scores (estimated indirect effect = 0.0132, boot-strapped standard error = 0.0015, boot-strapped standard 95% confidence interval = 0.0104, 0.0162). Additionally, PEF served as a significant mediator in the association between chair-standing time and cognitive function scores (estimated indirect effect = -0.0204, boot-strapped standard error = 0.0023, boot-strapped standard 95% confidence interval = -0.0251, -0.0159). CONCLUSION: The study highlights the importance of addressing declines in muscle strength and lung function to identify risk factors associated with cognitive function. Understanding these relationships can provide insights into potential pathways linking these variables and may aid in better prevention of cognitive decline. Further long-term longitudinal cohort studies are needed to explore the causality between these factors.

Association of kidney function with physical performance: the Maastricht study.

BACKGROUND: Kidney failure has been associated with decreased physical capacity, although evidence regarding the physical performance of individuals with earlier stages of chronic kidney disease (CKD) remains limited. METHODS: Cross-sectional data were derived from the prospective, population-based Maastricht Study. Multivariate linear regression models were fitted to assess the association of estimated glomerular filtration rate (eGFR) and albuminuria categories with physical performance test outcomes. RESULTS: Overall, 7396 participants were included. Compared to eGFR 60-90 ml/min/1.73 m2, values < 60 ml/min/1.73 m2 were associated with significantly shorter 6-min walk distance (ß: - 13.04 m, 95% confidence intervals-CI - 19.95; - 6.13), worse timed chair rise stand test time (ß: 0.91 s, 95% CI 0.36; 1.47), lower maximal grip (ß: - 0.83 kg, 95% CI - 1.50; - 0.15) and elbow flexion (ß: - 3.64 Nm, 95% CI - 7.11; - 0.16) strength. Additionally, eGFR > 90 ml/min/1.73 m2 was linked to significantly shorter 6-min walk distance (ß: - 6.13 m, 95% CI - 9.44; - 2.82). Urinary albumin excretion > 30 mg/24 h was associated with shorter 6-min walk distance (ß: - 12.48 m, 95% CI - 18.28; - 6.68), worse timed chair rise stand test time (ß: 0.51 s, 95% CI 0.11; 1.06), lower maximal grip (ß: - 1.34 kg, 95% CI - 1.91; - 0.76) and elbow flexion strength (ß: - 3.31 Nm, 95% CI - 5.80; - 0.82). CONCLUSIONS: Reduced eGFR and higher albuminuria levels were associated with worse physical performance, especially shorter 6-min walk distance and lower muscle strength. The relationship between eGFR and physical function was non-linear, with also high eGFR values being associated with worse performance, especially in the six-minute walk test.

Post-activation potentiation after isometric contractions is strongly related to contraction intensity despite the similar torque-time integral.

Post-activation potentiation (PAP) is defined as an enhanced contractile response of a muscle following its own contractile activity and is influenced by the intensity and duration of the conditioning contraction. The aim of this study was to determine if the combination of intensity and duration, that is, torque-time integral (TTI) is a determinant of PAP amplitude. We compared PAP amplitude following low-to-maximal voluntary conditioning contraction intensities with and without similar TTI in the knee extensors. Twelve healthy males completed two experimental sessions. Femoral nerve stimulation was applied to evoke single twitches on the relaxed quadriceps before and after isometric conditioning contractions of knee extensors. In one session, participants performed conditioning contractions without similar TTI (6 s at 100, 80, 60, 40 and 20% maximal voluntary contraction (MVC)), while they performed conditioning contractions with similar TTI in the other session (6 s at 100%, 7.5 s at 80%, 10 s at 60%, 15 s at 40%, and 30 s at 20% MVC). In both sessions, PAP amplitude was related to conditioning contraction intensity. The higher the conditioning contraction intensity with or without similar TTI, the higher PAP. Significant correlations were found (i) between PAP and conditioning contraction intensity with (r2 = 0.70; P < 0.001) or without similar TTI (r2 = 0.64; P < 0.001), and (ii) between PAP with and without similar TTI (r2 = 0.82; P < 0.001). The results provide evidence that TTI has a minor influence on PAP in the knee extensors. This suggests that to optimize the effect of PAP, it is more relevant to control the intensity of the contraction rather than the TTI.

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.

Test-Retest Reliability of Isokinetic Strength in Lower Limbs under Single and Dual Task Conditions in Women with Fibromyalgia.

Background: Previous research has established good test-retest reliability for isokinetic dynamometry in fibromyalgia. However, the reliability of this test under dual-task conditions has not been investigated in fibromyalgia. Methods: A total of 10 women with fibromyalgia participated in this study. Participants completed the concentric/concentric test. The dual-task condition involved subtracting two by two while performing the test. Results: Reliability analysis under the single condition showed "poor" to "excellent" values for maximum peak torque in knee extension and "moderate" to "excellent" values for average. "Poor" to "excellent" reliability values were found in knee flexion for the maximum and average. Dual-task condition in knee extension ranged from "moderate" to "excellent" for maximum and average values, and in knee flexion, it ranged from "poor" to "excellent" for maximum value and from "moderate" to "excellent" for average value. Conclusions: Isokinetic dynamometry demonstrated sufficient reliability for measuring strength in knee extension maximum and average during single-task and dual-task conditions, along with knee flexion dual-task average in fibromyalgia. For knee flexion single-task maximum and average and knee flexion dual-task maximum, we did not obtain sufficiently reliable measurements. Only the concentric/concentric test has been studied, and future studies with a larger sample size are needed in order to generalize the results.