Vitamin D as an intervention for improving quadriceps muscle strength in patients after anterior cruciate ligament reconstruction: study protocol for a randomized double-blinded, placebo-controlled clinical trial.

BACKGROUND: The goal of anterior cruciate ligament reconstruction (ACLR) is to restore the preinjury level of knee function to return to play (RTP). However, even after completing the rehabilitation programme, some patients may have persistent quadriceps muscle weakness affecting knee function which ultimately leads to a failure in returning to play. Vitamin D has been long recognized for its musculoskeletal effects. Vitamin D deficiency may impair muscle strength recovery after ACLR. Correcting vitamin D levels may improve muscle strength. METHODS: This is a double-blinded, randomized controlled trial to investigate the effects of vitamin D supplementation during the post-operative period on quadriceps muscle strength in anterior cruciate ligament (ACL)-injured patients. Patients aged 18-50 with serum vitamin D < 20 ng/ml, unilateral ACL injury, > 90% deficit in total quadriceps muscle volume on the involved leg compared with uninvolved leg, Tegner score 7 + , and no previous knee injury/surgery will be recruited. To assess patient improvement, we will perform isokinetic and isometric muscle assessments, ultrasound imaging for quadriceps thickness, self-reported outcomes, KT-1000 for knee laxity, biomechanical analysis, and Xtreme CT for bone mineral density. To investigate the effect of vitamin D status on quadriceps strength, blood serum samples will be taken before and after intervention. DISCUSSION: Patients with low vitamin D levels had greater quadriceps fibre cross-sectional area loss and impaired muscle strength recovery after ACL. The proposed study will provide scientific support for using vitamin D supplementation to improve quadriceps strength recovery after ACLR. TRIAL REGISTRATION: ClinicalTrials.gov NCT05174611. Registered on 28 November 2021.

Correlación entre marcadores inflamatorios con función física y composición corporal en adultos mayores de la comunidad: estudio transversal / Correlation between inflammatory markers with physical function and bodycomposition in community older adults: a cross-sectional study

Introducción: El envejecimiento está relacionado con diversas enfermedades crónicas que causan inflamación sistémica, caracterizada por un aumento en los niveles sanguíneos de interleucina 6 (IL-6) y factor de necrosis tumoral alfa (TNF-α). La función física y la composición corporal podrían estar relacionadas con estos marcadores inflamatorios en adultos mayores.Objetivo: Analizar la correlación entre marcadores inflamatorios sanguíneos, función física y composición corporal en adultos mayores de la comunidad.Metodología: Estudio transversal con 245 adultos mayores (hombres 68±6 años; mujeres: 69%) de la ciudad de Londrina, Brasil. Se analizaron los niveles sanguíneos de IL-6 y TNF-α con citometría de flujo. Para la evaluación física fue considerado el equilibrio estático con la prueba de estación unipodal (PEU), la fuerza de prensión manual (FPM) utilizando un dinamómetro digital y la capacidad aeróbica con la prueba de caminata de seis minutos (PC6M). Para la evaluación de la composición corporal, fueron considerados los siguientes perímetros: cadera, pantorrilla, cuádriceps, bíceps braquial, tríceps braquial y cintura. Se analizó la correlación de las variables inflamatorias con las de función física y composición corporal, utilizando Pearson o Spearman con el software SPSS versión 22.Resultados: Los niveles de IL-6 se correlacionaron con la PEU (r: -0.22; p: 0.002), el perímetro de tríceps (r: 0.16; p: 0.023) y el de cintura (r: 0.34; p: 0.000). Los niveles de TNF-α se correlacionaron con FPM (r: -0.15; p: 0.035), el perímetro de tríceps (r: 1.79; p: 0.012) y el de cintura (r: 0.27; p< 0.001). Conclusión: Los marcadores inflamatorios están relacionados con menor fuerza, equilibrio estático y un aumento en el perímetro de tríceps y cintura en adultos mayores de la comunidad.(AU)

Introduction: Aging is associated with various chronic dis-eases that cause systemic inflammation, characterized by an in-crease in blood levels of interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α). Physical function and body compositionmay be related to these inflammatory markers in older adults.Objective: To analyze the correlation between blood in-flammatory markers, physical function and body compositionin community-dwelling older adults.Methodology: A cross-sectional study was carried out with242 community-dwelling older adults (mean age was 68±6years for males and 70±6 years for females; the percentageof men was 36.6% and 69.4% of women) from the city ofLondrina, Brazil. Blood levels of IL-6 and TNF-α were analyzedwith flow cytometry. For the physical evaluation, static balancewas measured with the one-legged stance test (OLS), hand-grip strength (HGS) using a digital dynamometer and aerobiccapacity with the six-minute walk test (6MWT). For the evalu-ation of body composition, the following perimeters were con-sidered: hip, calf, quadriceps, biceps brachii, triceps brachiiand waist. The correlation of inflammatory variables withthose of physical function and body composition was analyzedusing Pearson or Spearman with SPSS version 22 software.Results: IL-6 levels were correlated with OLS (r: -0.22;p:0.002), triceps circumference (r: 0.16; p:0.023) and waist cir-cumference (r: 0.34; p:0.000). TNF-α levels were correlatedwith HGS (r: -0.15; p:0.035), triceps circumference (r: 1.79;p:0.012) and waist circumference (r: 0.27; p < 0.001).Conclusion: Inflammatory biomarkers are related to lowmuscle strength, static balance, and an increase in tricepsand waist circumference.(AU)

Creatine supplementation and resistance training to preserve muscle mass and attenuate cancer progression (CREATINE-52): a protocol for a double-blind randomized controlled trial.

BACKGROUND: Muscle mass is important for metastatic prostate cancer survival and quality of life (QoL). The backbone of treatment for men with metastatic castration sensitive prostate cancer (mCSPC) is androgen deprivation therapy (ADT) with an androgen signaling inhibitor. ADT is an effective cancer treatment, but it facilitates significant declines in muscle mass and adverse health outcomes important to mCSPC survivors, such as fatigue, and reductions in physical function, independence, insulin sensitivity, and QoL. In non-metastatic CSPC survivors, resistance training (RT) preserves muscle mass and improves these related health outcomes, but the biggest barrier to RT in CSPC survivors of all stages is fatigue. Creatine monohydrate supplementation coupled with RT (Cr + RT) may address this barrier since creatine plays a critical role in energy metabolism. Cr + RT in cancer-free older adults and other clinical populations improves muscle mass and related health outcomes. Evidence also suggests that creatine supplementation can complement cancer treatment. Thus, Cr + RT is a strategy that addresses gaps in survivorship needs of people with mCSPC. The purpose of this parallel, double-blind randomized controlled trial is to test the effects of 52-weeks of Cr + RT compared with placebo (PLA) and RT (PLA + RT) on muscle mass, other related health outcomes, and markers of cancer progression. METHODS: We will carry out this trial with our team's established, effective, home-based, telehealth RT program in 200 mCSPC survivors receiving ADT, and evaluate outcomes at baseline, 24-, and 52-weeks. RT will occur twice weekly with elastic resistance bands, and an established creatine supplementation protocol will be used for supplementation delivery. Our approach addresses a major facilitator to RT in mCSPC survivors, a home-based RT program, while utilizing a supervised model for safety. DISCUSSION: Findings will improve delivery of comprehensive survivorship care by providing a multicomponent, patient-centered lifestyle strategy to preserve muscle mass, improve health outcomes, and complement cancer treatment (NCT06112990).

Modification of velopharyngeal closure pressures during phonation by neuromuscular electrical stimulation in healthy individuals.

Introduction: Rhinophonia aperta may result from velopharyngeal insufficiency. Neuromuscular electrical stimulation (NMES) has been discussed in the context of muscle strengthening. The aim of this study was to evaluate in healthy subjects whether NMES can change the velopharyngeal closure pattern during phonation and increase muscle strength. Method: Eleven healthy adult volunteers (21-57 years) were included. Pressure profiles were measured by high resolution manometry (HRM): isolated sustained articulation of /a/ over 5 s (protocol 1), isolated NMES applied to soft palate above motor threshold (protocol 2) and combined articulation with NMES (protocol 3). Mean activation pressures (MeanAct), maximum pressures (Max), Area under curve (AUC) and type of velum reactions were compared. A statistical comparison of mean values of protocol 1 versus protocol 3 was carried out using the Wilcoxon signed rank test. Ordinally scaled parameters were analyzed by cross table. Results: MeanAct values measured: 17.15±20.69 mmHg (protocol 1), 34.59±25.75 mmHg (protocol 3) on average, Max: 37.86±49.17 mmHg (protocol 1), 87.24±59.53 mmHg (protocol 3) and AUC: 17.06±20.70 mmHg.s (protocol 1), 33.76±23.81 mmHg.s (protocol 3). Protocol 2 produced velum reactions on 32 occasions. These presented with MeanAct values of 13.58±12.40 mmHg, Max values of 56.14±53.14 mmHg and AUC values of 13.84±12.78 mmHg.s on average. Statistical analysis comparing protocol 1 and 3 showed more positive ranks for MeanAct, Max and AUC. This difference reached statistical significance (p=0.026) for maximum pressure values. Conclusions: NMES in combination with articulation results in a change of the velopharyngeal closure pattern with a pressure increase of around 200% in healthy individuals. This might be of therapeutic benefit for patients with velopharyngeal insufficiency.

Mitochondrial targeted catalase improves muscle strength following arteriovenous fistula creation in mice with chronic kidney disease.

Hand dysfunction is a common observation after arteriovenous fistula (AVF) creation for hemodialysis access and has a variable clinical phenotype; however, the underlying mechanism responsible is unclear. Grip strength changes are a common metric used to assess AVF-associated hand disability but has previously been found to poorly correlate with the hemodynamic perturbations post-AVF placement implicating other tissue-level factors as drivers of hand outcomes. In this study, we sought to test if expression of a mitochondrial targeted catalase (mCAT) in skeletal muscle could reduce AVF-related limb dysfunction in mice with chronic kidney disease (CKD). Male and female C57BL/6J mice were fed an adenine-supplemented diet to induce CKD prior to placement of an AVF in the iliac vascular bundle. Adeno-associated virus was used to drive expression of either a green fluorescent protein (control) or mCAT using the muscle-specific human skeletal actin (HSA) gene promoter prior to AVF creation. As expected, the muscle-specific AAV-HSA-mCAT treatment did not impact blood urea nitrogen levels (P = 0.72), body weight (P = 0.84), or central hemodynamics including infrarenal aorta and inferior vena cava diameters (P > 0.18) or velocities (P > 0.38). Hindlimb perfusion recovery and muscle capillary densities were also unaffected by AAV-HSA-mCAT treatment. In contrast to muscle mass and myofiber size which were not different between groups, both absolute and specific muscle contractile forces measured via a nerve-mediated in-situ preparation were significantly greater in AAV-HSA-mCAT treated mice (P = 0.0012 and P = 0.0002). Morphological analysis of the post-synaptic neuromuscular junction uncovered greater acetylcholine receptor cluster areas (P = 0.0094) and lower fragmentation (P = 0.0010) in AAV-HSA-mCAT treated mice. Muscle mitochondrial oxidative phosphorylation was not different between groups, but AAV-HSA-mCAT treated mice had lower succinate-fueled mitochondrial hydrogen peroxide emission compared to AAV-HSA-GFP mice (P < 0.001). In summary, muscle-specific scavenging of mitochondrial hydrogen peroxide significantly improves neuromotor function in mice with CKD following AVF creation.

Does inspiratory muscle training improve lung function and quality of life in people with inclusion body myositis? A pilot study.

Inclusion body myositis is the most common acquired myositis in adults, predominantly weakening forearm flexor and knee extensor muscles. Subclinical respiratory muscle weakness has recently been recognised in people with inclusion body myositis, increasing their risk of respiratory complications. Inspiratory muscle training, a technique which demonstrates efficacy and safety in improving respiratory function in people with neuromuscular disorders, has never been explored in those with inclusion body myositis. In this pilot study, six adults with inclusion body myositis (age range 53 to 81 years) completed eight weeks of inspiratory muscle training. Measures of respiratory function, quality of life, sleep quality and a two-minute walk test were performed pre and post-intervention. All participants improved their respiratory function, with maximal inspiratory pressure, sniff nasal inspiratory pressure and forced vital capacity increasing by an average of 50 % (p = .002), 43 % (p = .018) and 13 % (p = .003) respectively. No significant change was observed in quality of life, sleep quality or two-minute walk test performance. No complications occurred due to inspiratory muscle training This pilot study provides the first evidence that inspiratory muscle training may be safe and effective in people with Inclusion Body Myositis, potentially mitigating the complications of poor respiratory function.

20 years of neuromuscular electrical stimulation in COPD.

Although a lung disease, COPD is also associated with extrapulmonary manifestations including, among others, limb muscle dysfunction. Limb muscle dysfunction is a key systemic consequence of COPD that impacts patients' physical activity, exercise tolerance, quality of life and survival. Deconditioning is the main mechanism underlying the development of limb muscle dysfunction in COPD, which can be partially improved with exercise. However, some patients may not be able to tolerate exercise because of incapacitating breathlessness or unwillingness to undertake whole-body exercise. Alternative training modalities that do not give rise to dyspnoea, such as neuromuscular electrical stimulation (NMES), are urged. Over the past 20 years, NMES in COPD has presented conflicting conclusions in meta-analysis. In this review, we try to understand the reason for this result by analysing possible biases and factors that brought conflicting conclusions. We discuss the population (the intervention group, but also the control group), the outcome measures, the frequency of stimulation, the rehabilitation protocol (i.e. NMES alone versus standard care/rehabilitation or NMES plus conventional exercise training versus conventional exercise training alone or NMES versus sham treatment) and the trial design. The main reason for this discrepancy is the lack of dedicated guidelines for NMES. Further research is urged to determine the optimal parameters for an NMES programme. Despite this, NMES appears to be an effective means of enhancing quadriceps strength and exercise capacity in COPD with the potential to break the vicious circle induced by the disease and COPD patients' lifestyle.

Current state of research on exercise for the treatment of myasthenia gravis: A scoping review.

OBJECTIVE: To provide a comprehensive overview of existing evidence, research gaps, and future research priorities concerning the treatment of myasthenia gravis (MG) using exercise therapies. METHOD: Clinical studies on exercise treatment for MG were searched in nine databases to conduct a scoping review. Two independent researchers screened the literature and comprehensively analyzed the characteristics and limitations of the included articles. RESULTS: A total of 5725 studies were retrieved, of which 24 were included. The included studies were conducted in 16 different countries/regions and 456 patients were enrolled. Study designs included both interventional and observational studies. Exercise interventions included aerobic exercise, resistance exercise, balance training, and stretch training, and are typically administered in conjunction with medication, usual care, or some other interventions. The intensity, frequency, and duration of exercise interventions varied hugely among studies. Six-minute walk test, adverse events, muscle strength, MG quality of life-15 scale, forced vital capacity, quantitative MG scale, and MG activities of daily living scale were the most frequently used outcomes. All studies reported results in favor of the efficacy and safety of exercise in MG, and exercise-related adverse events were reported in two studies. CONCLUSION: This scoping review provides an overview of the evidence concerning exercise treatment for MG. Key gaps in evidence include a limited number of participants, complex interventions, variability in outcome selection, and insufficient reporting in publications. The promotion of exercise treatment for MG still encounters several obstacles. A larger population, rigorous study design and conduction, standardized interventions and outcomes, and standardized reporting are essential.

Systematic review and meta-analysis of nutrient supplements for treating sarcopenia in people with chronic obstructive pulmonary disease.

Individuals with chronic obstructive pulmonary disease (COPD) are prone to malnutrition and sarcopenia as a result of nutritional deficiencies and increased energy metabolism. However, the effects of nutrient supplements (NS) on treating sarcopenia in patients with COPD are not well established from systematic evidence. This meta-analysis examined the effect of NS on sarcopenia in patients with COPD. A systematic search of multiple databases was conducted, and 29 randomized controlled trials involving 1625 participants (age, mean [SD] = 67.9 [7.8] years) were analyzed. NS demonstrated significant improvements in body weight (MD,1.33 kg; 95% CI, 0.60, 2.05 kg; P = 0.0003; I2 = 87%), fat-free mass index (MD, 0.74 kg/m2; 95% CI, 0.21, 1.27 kg/m2; P = 0.007; I2 = 75%), and 6-min walk test (MD, 19.43 m; 95% CI, 4.91, 33.94 m; P = 0.009; I2 = 81%) compared with control. However, NS had nonsignificant effects on handgrip strength (SMD, 0.36; 95% CI, - 0.15, 0.88; P = 0.16; I2 = 87%) and quadriceps muscle strength (SMD, 0.11; 95% CI, -  0.06, 0.27; P = 0.20; I2 = 25%) compared with the control. In conclusion, NS may be an effective treatment for improving body composition and physical performance in COPD. Future studies should explore the effects of intervention durations, specific NS types, or combined training in patients with COPD and sarcopenia.

Exome-Based Amino Acid Optimization: A Dietary Strategy to Satisfy Human Nutritional Demands and Enhance Muscle Strength in Breast Tumor Mice Undergoing Chemotherapy.

Breast cancer patients undergoing chemotherapy often experience muscle wasting and weakness, which impact their quality of life. A potential solution lies in customizing amino acid compositions based on exome-derived formulations (ExAAs). The study hypothesized that tailoring dietary amino acids using ExAAs could enhance muscle health. Theoretical amino acid requirements were calculated from the genome's exome region, and a breast cancer mouse model undergoing paclitaxel treatment was established. The mice were supplemented with a cancer-specific nutritional formula (QJS), and the effects of QJS and amino acid-adjusted QJS (adjQJS) were compared. Both formulations improved the nutritional status without compromising tumor growth. Notably, adjQJS significantly enhanced muscle strength compared to QJS (1.51 ± 0.25 vs. 1.30 ± 0.08 fold change, p < 0.05). Transcriptome analysis revealed alterations in complement and coagulation cascades, with an observed upregulation of C3 gene expression in adjQJS. Immune regulation also changed, showing a decrease in B cells and an increase in monocytes in skeletal muscle with adjQJS. Importantly, adjQJS resulted in a notable increase in Alistipes abundance compared to QJS (10.19 ± 0.04% vs. 5.03 ± 1.75%). This study highlights the potential of ExAAs as valuable guide for optimizing amino acid composition in diets for breast cancer patients undergoing chemotherapy.

Relationship between hemoglobin and grip strength in older adults: the ActiFE study.

INTRODUCTION: Although anemia is associated with low muscle strength, hemoglobin has been rarely studied considering ferritin. AIM: To analyze the association between hemoglobin and grip strength in community-dwelling older adults. METHODS: We used data from a German cohort of adults ≥ 65 years, excluding those with CRP > 10 mg/L or taking iron supplements. Grip strength (kg) was measured using a Jamar dynamometer. Analysis was performed using multiple linear regression, adjusted for established confounders. Due to interaction, age-stratified (< 80, 80 +), further sex-stratified analysis in those < 80 years old and ferritin-stratified in men < 80 years were performed. RESULTS: In total, 1294 participants were included in this analysis (mean age 75.5 years, 549 (42.3%) women, 910 (70.3%) < 80 years). On average, hemoglobin and grip strength were 14.9 g/dL and 41.3 kg for men, 13.9 g/dL and 25.1 kg for women. Hemoglobin was significantly positively associated with grip strength only among women < 80 years (ß 0.923 [95% CI 0.196, 1.650]). For men < 80 years, the association was significant when ferritin was ≥ 300 µg/L (ß 2.028 [95% CI 0.910, 3.146]). No association was detected among those participants 80 + . DISCUSSION AND CONCLUSIONS: Our data show an association between hemoglobin and grip strength only in women < 80 years old. For men < 80 years, the association was only significant with ferritin levels ≥ 300 µg/L. Considering the decreasing levels of hemoglobin and grip strength and the high prevalence of iron deficiency in older adults further analyses investigating this relationship with more iron specific parameters such as transferrin saturation are warranted.

Effects of upper limbs' neuromuscular electrical stimulation (NMES) superimposed to voluntary contraction added to a protocol of intradialytic leg cycle ergometer exercise, in muscle strength, functional capacity and quality of life of adult patients with CKD: a randomized clinical trial protocol.

OBJECTIVE: To investigate the effects of unilateral upper limbs' (ULM) neuromuscular electrical stimulation (NMES) superimposed on a voluntary contraction added to a protocol of intradialytic leg cycle ergometer exercise on muscle strength, functional capacity and quality of life of adult patients with chronic kidney disease (CKD). METHODS: This randomized controlled clinical trial will be carried out at a Brazilian University Hospital. The patients will be evaluated and randomly allocated to an intervention group (i.e., unilateral NMES on the upper limb without hemodialysis fistula for 20 min and leg cycle ergometer for 30 min) or a control group (i.e., unilateral NMES-Sham on the upper limb without hemodialysis fistula for 20 min and leg cycle ergometer for 30 min). The patients will be treated for 8 weeks, with three weekly treatment sessions totaling 24 sessions. MEASUREMENTS: ULM muscle strength, functional capacity, quality of life and also the feasibility, safety and patient adherence to the exercise protocol. All physical measurements will be collected by trained researchers before treatment (week 0) and at the end of treatment (week 9), always in the second hemodialysis session of the week. It will be used in an intention-to-treat analysis. RESULTS/CONCLUSIONS: The outcomes of this clinical trial protocol may help to know the possible benefits of unilateral ULM' NMES superimposed on a voluntary contraction added to a protocol of leg cycle ergometer for patients with CKD and to aid clinical decisions about future implementation or not of this technique (NMES) in intradialytic physical training programs.

Scapular stabilization exercise training improves treatment effectiveness on shoulder pain, scapular dyskinesis, muscle strength, and function in patients with subacromial pain syndrome: A randomized controlled trial.

INTRODUCTION: Subacromial pain syndrome (SPS) is a common cause of shoulder pain, and is associated with functional limitation, workdays lost, disability, and poor quality of life. PURPOSE: Our purpose was to investigate the effects of scapular stabilization exercises in patients with SPS. METHOD: Sixty-four patients with SPS who also exhibit observable scapular dyskinesis defined by the scapular dyskinesis test were recruited and randomized to scapular stabilization exercise training group or to control group. All participants received the same rehabilitation protocol including glenohumeral and scapular mobilization, pendulum exercises, shoulder stretching, range of motion exercises, strengthening, and proprioceptive exercises. Patients in the scapular stabilization exercise training group performed additional scapular stabilization exercises. The presence of scapular dyskinesis, shoulder pain severity, motion, muscle strength, scapular upward rotation, and shoulder disability were assessed before and after the four-week rehabilitation program. RESULTS: The scapular stabilization exercise training group had better improvement in scapular dyskinesis, pain, muscle strength, and shoulder disability compared to the control group (p < 0.05). However, there was no statistically significant time-group interaction regarding shoulder motion and scapular upward rotation (p > 0.05). CONCLUSIONS: Scapular stabilization exercises added to the shoulder mobilization, stretching, and strengthening are effective in improving scapular dyskinesis, reducing pain, increasing muscle strength and shoulder function in patients with SPS accompanied by scapular dyskinesis.

Effect of foam rolling recovery on pain and physical capacity after resistance exercises: A randomized crossover trial.

OBJECTIVES: To compare the effects of passive recovery (PR), active recovery (AR), and recovery through self-massage with the aid of foam rolling (FRR) on pain and physical capacity in healthy volunteers after a resistance exercise (RE) session. METHODS: The sample of this randomized crossover trial comprised 37 physically healthy men who underwent three sessions of RE (squat, leg press, and leg extension), involving four sets of 10 repetitions with 80% of 10MR, with an interval of seven days between sessions. PR consisted of sitting for 20min, AR included a cycle ergometer for 20min at 50% maximum heart rate, and FRR involved 10 repetitions per target body area, followed by 1min rest. Variables of physical capacity (strength, power, agility, joint range of motion, flexibility, speed, and fatigue resistance) were assessed 1h after RE, whereas pain was assessed 24h, 48h, and 72h after RE. RESULTS: In the dominant lower limb, the percentage of strength decreased (p < 0.001) by 16.3% after RE but improved (p < 0.001) by 5.2% after AR and FRR in relation to PR. Similar results were observed in the non-dominant lower limb. Agility was enhanced (p < 0.001) by 3.6% in AR and 4.3% in FRR compared with the baseline assessment. The recoveries for the other physical variables were similar. Only FRR reduced (p < 0.001) pain at 24h (22.8%), 48h (39.2%), and 72h (59.7%) compared to PR. CONCLUSIONS: Self-massage using a foam roll reduced pain and improved agility and muscle strength during recovery after exercise. TRIAL REGISTRATION NUMBER: NCT04201977.

Correlation between hip muscle strength and the lower quarter Y-balance test in athletes following anterior cruciate ligament reconstruction.

INTRODUCTION: The lower quarter Y-balance test (YBT-LQ), which measures dynamic postural control, has been reported to be predictive of lower limb injuries in athletes. It requires subjects to control their body while maintaining a single-leg stance, which necessitates sufficient strength of the hip muscles to maintain stability. The purpose of the study was to investigate the correlation between the performance of the YBT-LQ and the hip abductor or extensor muscle strength in athletes following anterior cruciate ligament reconstruction surgery (ACLR). METHODS: Fifteen athletes with post-ACLR participated in this cross-sectional study. The participants completed the YBT-LQ, followed by isokinetic measurement of the hip abductor and extensor muscles of both the legs. The peak and average torque of the hip abductor and extensor muscles were tallied with the composite score of the YBT-LQ for each limb. RESULTS: No correlation was found between the strength of the hip muscles and the YBT-LQ composite score in both injured and non-injured limbs at all velocities except for the eccentric hip abductor and concentric hip extensor torques. The eccentric hip abductor average torque is strongly associated with the YBT-LQ (r = 0.663, p = 0.010) at a speed of 180°/s. The concentric hip extensor peak torque was weakly correlated with balance (r = 0.540, p = 0.046) at a speed of 180°/s. CONCLUSION: Our study demonstrated a positive correlation between the YBT-LQ and eccentric hip abduction and concentric hip extension at higher velocities. This shows the importance of implementing velocity-oriented rehabilitation in an athletic population following ACLR.

Prediction models for physical function in COVID-19 survivors.

BACKGROUND: The burden of caring for patients who have survived COVID-19 will be enormous in the coming years, especially with respect to physical function. Physical function has been routinely assessed using the Post-COVID-19 Functional Status (PCFS) scale. AIM: This study built prediction models for the PCFS scale using sociodemographic data, clinical findings, lung function, and muscle strength. METHOD: Two hundred and one patients with post-COVID-19 syndrome (PCS) completed the PCFS scale to assess physical function. Their levels of general fatigue were also assessed using the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) scale, handgrip strength (HGS), and spirometry. RESULTS: The number of participants who scored 0 (none), 1 (negligible), 2 (slight), 3 (moderate), and 4 (severe) on the PCFS scale was 25 (12%), 40 (20%), 39 (19%), 49 (24%), and 48 (24%), respectively. The PCFS scale was significantly correlated with the following variables: FACIT-F score (r = -0.424, P < 0.001), HGS (r = -0.339, P < 0.001), previous hospitalization (r = 0.226, P = 0.001), body mass index (r = 0.163, P = 0.021), and sex (r = -0.153, P = 0.030). The regression model with the highest coefficient of regression (R = 0.559) included the following variables: age, sex, body mass index, FACIT-F, HGS, and previous hospitalization. CONCLUSIONS: Worse general fatigue and HGS are associated with more severe physical function impairments in PCS patients. Furthermore, a history of prior hospitalization results in worse physical function. Thus, prediction models for the PCFS scale that incorporate objective measures enable a better assessment of the physical function of these patients, thus helping in the selection of candidates for a program of physical reconditioning.

Multimodal and conventional resistance training interventions improve muscle function in older adults: Findings from the Training IMCT study.

Age-associated remodeling processes affect the intramuscular connective tissue (IMCT) network, which may significantly impair muscle function. Thus, we aimed to test whether including exercises shown to efficiently target the IMCT to a conventional resistance exercise intervention (CONV) would result in greater functional gains as compared to CONV alone. Fifty-three men and women (66.2 ± 3.3 years) were assigned to either CONV (n = 15), multimodal training (MULTI; n = 17) or a control (CTRL; n = 21) group. All subjects were tested at baseline, and those assigned to CONV or MULTI underwent a 16-week training intervention. The CONV group followed a progressive resistance training program, in which the number of weekly training sessions gradually increased from 1 to 3. In the MULTI group, one of these sessions was replaced with plyometric training, followed by self-myofascial release. Testing included maximal strength and power, imaging-based muscle volume, architecture, and functional performance. The intervention effects were analyzed using two- or three-way repeated measures ANOVA models (α = 0.05). Briefly, the maximal knee extension isometric contraction, one-repetition maximum, and isokinetic peak torque increased in all groups (p < 0.05), albeit to a lesser extent in CTRL. On the other hand, quadriceps femoris muscle volume (p = 0.019) and vastus lateralis pennation angle (p < 0.001) increased only in the MULTI group. Handgrip strength did not change in response to the intervention (p = 0.312), whereas Sit-to-Stand performance improved in all groups after the first 8-wks, but only in MULTI and CONV after 16-wks (all p < 0.001). In conclusion, we found that a resistance training intervention in which one weekly training session is replaced by plyometric training is feasible and as effective as a program consisting solely of conventional strength training sessions for inducing gains in muscle strength and function in older adults. Muscle size and architecture improved only in the MULTI group. German Clinical Trials: DRKS00015750.

Novel dietary strategies to manage sarcopenia.

PURPOSE OF REVIEW: Sarcopenia is a wasting disease, mostly age-related in which muscle strength and mass decline, such as physical performance. With aging, both lower dietary protein intake and anabolic resistance lead to sarcopenia. Moreover, aging and sarcopenia display low-grade inflammation, which also worsen muscle condition. In this review, we focused on these two main targets to study dietary strategies. RECENT FINDINGS: The better understanding in mechanisms involved in sarcopenia helps building combined dietary approaches including physical activity that would slow the disease progression. New approaches include better understanding in the choice of quality proteins, their amount and schedule and the association with antioxidative nutrients. SUMMARY: First, anabolic resistance can be countered by increasing significantly protein intake. If increasing amount remains insufficient, the evenly delivery protein schedule provides interesting results on muscle strength. Quality of protein is also to consider for decreasing risk for sarcopenia, because varying sources of proteins appears relevant with increasing plant-based proteins ratio. Although new techniques have been developed, as plant-based proteins display a lower availability, we need to ensure an adapted overall amount of proteins. Finally, specific enrichment with leucine from whey protein remains the dietary combined approach most studied and studies on citrulline provide interesting results. As cofactor at the edge between anabolic and antioxidative properties, vitamin D supplementation is to recommend. Antioxidative dietary strategies include both fibers, vitamins, micronutrients and polyphenols from various sources for positive effects on physical performance. The ω 3 -polyunsaturated fatty acids also display positive modifications on body composition. Gut microbiota modifiers, such as prebiotics, are promising pathways to improve muscle mass and function and body composition in sarcopenic patients. Nutritional interventions could be enhanced by combination with physical activity on sarcopenia. In healthy older adults, promoting change in lifestyle to get near a Mediterranean diet could be one of the best options. In sarcopenia adults in which lifestyle changes appears unprobable, specific enrichement potentialized with physical activity will help in the struggle against sarcopenia. Longitudinal data are lacking, which makes it hard to draw strong conclusions. However, the effects of a physical activity combined with a set of nutrition interventions on sarcopenia seems promising.

Effects of active vitamin D analogues on muscle strength and falls in elderly people: an updated meta-analysis.

Background: Elderly people are at high risk of falls due to decreased muscle strength. So far, there is currently no officially approved medication for treating muscle strength loss. The active vitamin D analogues are promising but inconsistent results have been reported in previous studies. The present study was to meta-analyze the effect of active vitamin D analogues on muscle strength and falls in elderly people. Methods: The protocol was registered with PROSPERO (record number: CRD42021266978). We searched two databases including PubMed and Cochrane Library up until August 2023. Risk ratio (RR) and standardized mean difference (SMD) with 95% confidence intervals (95% CI) were used to assess the effects of active vitamin D analogues on muscle strength or falls. Results: Regarding the effects of calcitriol (n= 1), alfacalcidol (n= 1) and eldecalcitol (n= 1) on falls, all included randomized controlled trials (RCT) recruited 771 participants. Regarding the effects of the effects of calcitriol (n= 4), alfacalcidol (n= 3) and eldecalcitol (n= 3) on muscle strength, all included RCTs recruited 2431 participants. The results showed that in the pooled analysis of three active vitamin D analogues, active vitamin D analogues reduced the risk of fall by 19%. Due to a lack of sufficient data, no separate subgroup analysis was conducted on the effect of each active vitamin D analogue on falls. In the pooled and separate analysis of active vitamin D analogues, no significant effects were found on global muscle, hand grip, and back extensor strength. However, a significant enhancement of quadriceps strength was observed in the pooled analysis and separate analysis of alfacalcidol and eldecalcitol. The separate subgroup analysis on the impact of calcitriol on the quadriceps strength was not performed due to the lack to sufficient data. The results of pooled and separate subgroup analysis of active vitamin D analogues with or without calcium supplementation showed that calcium supplementation did not affect the effect of vitamin D on muscle strength. Conclusions: The use of active vitamin D analogues does not improve global muscle, hand grip, and back extensor strength but improves quadriceps strength and reduces risk of falls in elderly population.