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OBJECTIVE: To explore the relationship between knee crepitus, quadriceps muscle thickness and isometric strength in individuals with patellofemoral pain (PFP). DESIGN: Cross-sectional. PARTICIPANTS: Individuals with PFP. MAIN OUTCOME MEASURES: Participants with PFP underwent assessments for presence, frequency and severity of knee crepitus. Real-time ultrasound images of the quadriceps muscles (rectus femoris, vastus medialis and lateralis) at rest and during contraction were obtained, muscle thickness was measured in both conditions. Maximal voluntary isometric contraction tests were performed to measure knee extensor strength. The relationship between knee crepitus and quadriceps muscle thickness and knee extensor strength was explored using logistic and linear regressions. RESULTS: Sixty individuals with PFP were included (age: 24; 60% women; 38% with crepitus). Knee crepitus severity was related to rectus femoris and vastus medialis thickness during rest (R2 = 0.19 and 0.09, respectively) and contraction (R2 = 0.16 and 0.07, respectively) and with vastus lateralis during contraction (R2 = 0.08). Isometric knee extensor strength was not related to knee crepitus presence, frequency, or severity. CONCLUSION: Higher severity of knee crepitus is related to lower quadriceps muscle thickness in individuals with PFP. There is no relationship between the presence and frequency of knee crepitus with quadriceps muscle thickness or knee extensor strength.
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Contração Isométrica , Força Muscular , Síndrome da Dor Patelofemoral , Músculo Quadríceps , Ultrassonografia , Humanos , Estudos Transversais , Músculo Quadríceps/diagnóstico por imagem , Músculo Quadríceps/fisiopatologia , Músculo Quadríceps/fisiologia , Feminino , Força Muscular/fisiologia , Masculino , Síndrome da Dor Patelofemoral/fisiopatologia , Síndrome da Dor Patelofemoral/diagnóstico por imagem , Contração Isométrica/fisiologia , Adulto Jovem , Adulto , Articulação do Joelho/fisiopatologia , Articulação do Joelho/diagnóstico por imagemRESUMO
This study aimed to verify the relationship between changes in thigh muscle-localized bioelectrical impedance analysis (ML-BIA) parameters and performance in a multiple-set exercise. The sample consisted of 30 female university students (22.1 ± 3.2 years). The ML-BIA parameters, including localized muscle resistance (ML-R), reactance (ML-Xc), and phase angle (ML-AngF), were evaluated using a tetrapolar bioelectric impedance device operating at a frequency of 50 KHz. The multiple sets protocol was performed with an isokinetic dynamometer. For body composition, total and leg lean soft tissue (LST) were evaluated using dual X-ray absortiometry. Student's t-test for paired samples was used to compare the ML-BIA parameters and thigh circumference pre and postexercise. Linear regression analysis was performed to verify the ∆ML-PhA as a predictor of peak torque for the three sets alone while controlling for total and leg LST. There were differences in the ML-R (∆ = 0.02 ± 1.45 Ω; p = 0.001; and E.S = 0.19), ML-Xc (∆ = 2.90 ± 4.12 Ω; p = 0.043; and E.S = 0.36), and thigh circumference (∆ = 0.82 ± 0.60 cm; p < 0.001; and E.S = 0.16) pre- and post-multiple sets. ΔML-PhA was a predictor of performance in the first set (p = 0.002), regardless of total and leg LST. However, the ΔML-PhA lost its explanatory power in the other sets (second and third), and the variables that best explained performance were total and leg LST. The ML-BIA (ML-R and ML-Xc) parameters were sensitive and changed after the multiple sets protocol, and the ΔML-PhA was a predictor of performance in the first set regardless of the total and leg LST.
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Composição Corporal , Impedância Elétrica , Dinamômetro de Força Muscular , Músculo Esquelético , Humanos , Feminino , Adulto Jovem , Composição Corporal/fisiologia , Músculo Esquelético/fisiologia , Adulto , Coxa da Perna/fisiologia , Torque , Força Muscular/fisiologia , Exercício Físico/fisiologia , Desempenho Atlético/fisiologiaRESUMO
Breast cancer is the most common cancer in women worldwide, and its treatment usually involves a combination of many medical procedures, including surgery, chemotherapy, radiotherapy, and hormonal therapy. One of the detrimental effects on physical function is reduced upper limb muscle strength. This study aimed to evaluate upper body strength intra-day and inter-day (test-retest) reliability using the handgrip strength test (HGS) and the bilateral isometric bench press (BIBP) and the test-retest reliability of the one repetition maximum on the bench press (BP-1RM) in breast cancer survivors (BCS). Thirty-two (52.94 ± 8.99 yrs) BCS participated in this study. The muscle strength tests were performed in two different moments, three to seven days apart. Intraclass coefficient correlation (ICC) and coefficient of variation (CV) were used to assess the reliability. Standard error of measurement (SEM), typical error of measurement (TEM), and minimally detectable change (MDC) analyses were performed. The Bland-Altman analysis was used to assess the agreement between test-retest. We found a reliability that can be described as "high" to "very high" (ICC ≥ 0.88; CV ≤ 10%) for intra-day and test-retest. SEM% and MDC% were lower than 5% and 11%, respectively, for all intra-day testing. SEM% and TEM% ranged from 3% to 11%, and MDC% ranged from 9% to 23% in the test-retest reliability. The agreement demonstrated a systematic bias ranging from 2.3% to 6.0% for all testing, and a lower systematic bias may be presented in the non-treated side assessed by HGS and BIBP. HGS, BIBP, and BP-1RM assessments are reliable for measuring upper-body muscle strength in BCS.
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Neoplasias da Mama , Sobreviventes de Câncer , Força da Mão , Força Muscular , Humanos , Feminino , Reprodutibilidade dos Testes , Pessoa de Meia-Idade , Força Muscular/fisiologia , Força da Mão/fisiologia , Adulto , Contração Isométrica/fisiologia , Extremidade Superior/fisiopatologiaRESUMO
Spinal cord injury (SCI) is a condition that significantly affects the quality of life (QoL) of individuals, causing motor, physiological, social, and psychological impairments. Physical exercise plays a crucial role in maintaining the health and functional capacity of these individuals, helping to minimize the negative impacts of SCI. The aim of this study was to evaluate the effect of detraining (DT) (reduction or cessation of physical exercise) during the pandemic on five individuals with thoracic SCI. We assessed muscle strength using strength tests, functional capacity using a functional agility test, mental health using anxiety and depression inventories, and body composition using dual-energy X-ray absorptiometry (DEXA). The results after 33 months of DT showed significant losses in functional agility and MS, as well as a worsening in symptoms of anxiety and depression. It was observed that total body mass and fat mass (FM) exhibited varied behaviors among the individuals. Similarly, the results for lean body mass were heterogeneous, with one participant showing significant deterioration. It is concluded that DT caused by the pandemic worsened the physical and mental condition of individuals with SCI, highlighting the importance of continuous exercise for this population and underscoring the need for individual assessments to fully understand the impacts of DT.
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Composição Corporal , Saúde Mental , Força Muscular , Traumatismos da Medula Espinal , Humanos , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/psicologia , Masculino , Adulto , Pessoa de Meia-Idade , Feminino , COVID-19/psicologia , Exercício Físico , Qualidade de Vida , Ansiedade/fisiopatologia , Depressão/fisiopatologiaRESUMO
The greater muscle fiber cross-sectional area (CSA) is associated with greater skeletal muscle mass and strength, whereas muscle fiber atrophy is considered a major feature of sarcopenia. Muscle fiber size is a polygenic trait influenced by both environmental and genetic factors. However, the genetic variants underlying inter-individual differences in muscle fiber size remain largely unknown. The aim of our study was to determine whether 1535 genetic variants previously identified in a genome-wide association study of appendicular lean mass are associated with the CSA of fast-twitch muscle fibers (which better predict muscle strength) in the m. vastus lateralis of 148 physically active individuals (19 power-trained and 28 endurance-trained females, age 28.0 ± 1.1; 28 power-trained and 73 endurance-trained males, age 31.1 ± 0.8). Fifty-seven single-nucleotide polymorphisms (SNPs) were identified as having an association with muscle fiber size (p < 0.05). Of these 57 SNPs, 31 variants were also associated with handgrip strength in the UK Biobank cohort (n = 359,729). Furthermore, using East Asian and East European athletic (n = 731) and non-athletic (n = 515) cohorts, we identified 16 SNPs associated with athlete statuses (sprinter, wrestler, strength, and speed-strength athlete) and weightlifting performance. All SNPs had the same direction of association, i.e., the lean mass-increasing allele was positively associated with the CSA of muscle fibers, handgrip strength, weightlifting performance, and power athlete status. In conclusion, we identified 57 genetic variants associated with both appendicular lean mass and fast-twitch muscle fiber size of m. vastus lateralis that may, in part, contribute to a greater predisposition to power sports.
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Fibras Musculares Esqueléticas , Polimorfismo de Nucleotídeo Único , Humanos , Masculino , Feminino , Polimorfismo de Nucleotídeo Único/genética , Adulto , Fibras Musculares Esqueléticas/patologia , Estudo de Associação Genômica Ampla , Genômica , Força da Mão , Força Muscular/genética , AtletasRESUMO
INTRODUCTION AND HYPOTHESIS: Transcranial direct current stimulation (tDCS) can enhance muscle function in healthy individuals. However, it is unknown if tDCS associated with pelvic floor muscle training (PFMT) can improve pelvic floor muscle function (PFMF) in healthy women. The aim of this study was to investigate the acute effect of a single session of tDCS in PFMF compared with sham-tDCS in healthy women. METHODS: A double-blind, cross-over, randomized clinical trial was conducted with healthy, nulliparous and sexually active women. PFMF was assessed by bidigital palpation (PERFECT scale) and intravaginal pressure by a manometer (Peritron™). Participants randomly underwent two tDCS sessions (active and sham) 7 days apart. The electrode was positioned equal for both protocols, the anode electrode in the supplementary motor area (M1) and the cathode electrode in the right supraorbital frontal cortex (Fp2). The current was applied for 20 min at 2 mA in active stimulation and for 30 s in sham-tDCS. The tDCS applications were associated with verbal instructions to PFMT in a seated position. After each tDCS session PFMF was reevaluated. RESULTS: Twenty young healthy women (aged 23.4 ± 1.7 years; body mass index 21.7 ± 2.2 kg/m2) were included. No difference was observed in power, endurance, and intravaginal pressure of PFMF (p > 0.05). The number of sustained contractions improved from 3.0 (2.0-3.5) to 4.0 (3.0-5.0) after active-tDCS (p = 0.0004) and was superior to sham-tDCS (p = 0.01). CONCLUSION: The number of sustained contractions of PFM improved immediately after a single active-tDCS session, with a difference compared with the post-intervention result of sham-tDCS in healthy young women.
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Estudos Cross-Over , Diafragma da Pelve , Estimulação Transcraniana por Corrente Contínua , Humanos , Feminino , Diafragma da Pelve/fisiologia , Método Duplo-Cego , Adulto Jovem , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto , Voluntários Saudáveis , Contração Muscular/fisiologiaRESUMO
BACKGROUND: Phase angle (PhA) is an indicator of cellular health, function, and integrity. PhA has been considered an indicator of nutritional and health status, but it is uncertain whether it could be used as a fitness or athletic performance indicator. OBJECTIVE: To analyze the relationship between PhA and the fitness and athletic performance of adolescent boxers and to know whether this association is independent of body composition. METHODS: Thirty-seven trained youth boxers (15-18 y old) participated in the study. Participants underwent anthropometry and bioelectrical impedance assessments. The following tests were conducted: Fitness-Gram battery; speed, agility, and quickness; ball throws; punch impact force; bench press maximal strength; and vertical and horizontal jumps. Linear regression models were estimated and adjusted by covariates. RESULTS: The PhA was related to upper-limb strength. Nevertheless, in linear regression models, after adjusting models by body composition, only PhA remained as a predictor of relative maximal strength. The PhA was not a predictor of speed, agility, and quickness; cardiorespiratory fitness; or lower-limb power, in which adiposity was the main predictor of fitness. CONCLUSIONS: In adolescent boxers, PhA can predict upper-limb maximal strength independently of bioelectrical impedance analysis premises. However, compared with mucle mass, PhA is not a better predictor of upper-limb maximal strength.
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Background: The present study aimed to investigate the effects of post-activation performance enhancement (PAPE) after three warm-up protocols on back squat performance in trained men. Methods: Fourteen resistance-trained men performed conditioning activity (CA) with high-load (HL-CA), low-load (LL-CA), or usual specific warm-up as a control (CON). HL-CA consisted of one set of three repetitions with 90% of one repetition maximum (RM); LL-CA consisted of one set of six repetitions with 45% of 1 RM performed at maximal velocity; CON involved eight repetitions with 45% of 1 RM at controlled velocity. The participant's performance was measured using the total number of repetitions and volume load (reps × load × sets). Results: There were no significant differences between warm-up for the total number of repetitions (p = 0.17) or total volume load (p = 0.15). There was no difference between conditions for the number of repetitions (main condition effect; p = 0.17); however, participants achieved a significantly higher volume load after HL-PAPE than after CON for the first set (p = 0.04). Conclusion: High or low equated-load CA used as warm-up strategies did not potentiate subsequent performance enhancement in multiple-set back squat exercise performed until muscle failure in comparison with usual warm-up.
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Exercício de Aquecimento , Humanos , Masculino , Exercício de Aquecimento/fisiologia , Adulto , Treinamento Resistido/métodos , Adulto Jovem , Força Muscular/fisiologia , Desempenho Atlético/fisiologiaRESUMO
Background/Objectives: Post-COVID-19 condition can manifest through various symptoms such as dyspnea, cognitive disturbances, and fatigue, with mechanisms related to these symptoms, particularly those related to fatigue, still requiring further clarification. Therefore, our aim was to assess the clinical and physiological variables in patients with post-COVID-19 condition and persistent fatigue. Methods: After one year post-COVID-19 infection, the patients underwent a comprehensive evaluation, including a complete blood count, a metabolic panel, complete spirometry, and assessments of dyspnea, quality of life, anxiety and depression, physical capacity, body composition, muscle strength, comorbidities, and medications. The participants were categorized into two groups: G1-fatigue and G2-non-fatigue. Results: Seventy-seven patients (53% female; 55 ± 11.8 years) were included, 37 in G1 and 40 in G2. As for clinical markers and symptoms of illness, in those with persistent fatigue symptoms, a greater sensation of dyspnea [BDI score: 7.5 (6-9) vs. 12 (9-12), p < 0.001; mMRC score: 1 (1-2) vs. 0 (0-1), p = 0.002], worse quality of life [SGRQ total score: 1404 (1007-1897) vs. 497 (274-985); p < 0.001], higher levels of anxiety [HADS-A score: 8 (5-9) vs. 3 (0.5-4); p < 0.001], and a reduction in peripheral and inspiratory muscle strength [handgrip strength: 34 (28-40) vs. 40 (30-46.5) kgf, p = 0.044; MIP: -81 ± 31 vs. -111 ± 33 mmHg, p < 0.001)] were observed. Conclusions: Those with persistent fatigue exhibited a greater sensation of dyspnea, higher levels of anxiety, reduced peripheral and inspiratory muscle strength, and a greater impairment of quality of life. The severity of fatigue was influenced by the worsening quality of life, heightened anxiety levels, and decreased peripheral muscle strength. Additionally, the worse quality of life was associated with a higher sensation of dyspnea, lower muscle strength, and reduced physical capacity.
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This study aimed to determine, through the use of a highly sensitive statistical tool, whether real changes in performance were present; and compare the rates of meaningful variations in strength, speed, and power parameters at different time-points during the competitive season in national team rugby players. Thirty-two players were assessed 5 times across the season using the following tests: squat jump and countermovement jump tests; 30-m sprint velocity; and one-repetition maximum (1RM) in the half-squat and bench-press exercises. A repeated-measures analysis of variance was conducted to test for differences between successive time-points. Individual coefficients of variation values were used to set target scores for post-measurements and examine whether changes in performance parameters were greater than the natural test variance, thus providing an indication of whether "true changes" occurred. No significant changes were detected in the vertical jump height, 1RM measures, and sprint velocity and momentum throughout the 11-month period (P > 0.05). True changes occurred much more frequently for strength-power measures than for sprint velocity and momentum. Elite rugby union players did not exhibit significant variations in neuromuscular performance across the competitive period, when a group-based analysis was conducted. However, at the individual level, "true changes" in strength-power-(but not in speed-) related qualities were consistently observed over the competitive season.
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BACKGROUND: Whole body vibration (WBV) exercise is a therapy used for individuals with low tolerance to conventional exercises, such as patients with chronic obstructive pulmonary disease (COPD). This study aimed to assess the impact of WBV exercise on the functional capacity, muscle strength, and health-related quality of life (HRQoL) in severe COPD patients. METHODS: Studies published until March 2024 were reviewed, encompassing randomized clinical trials (RCTs) without temporal or linguistic constraints, comparing WBV exercise with other interventions. The PubMed/MEDLINE, Scopus, Cochrane Airways Trials Register, and CINAHL databases were queried. The Revised Cochrane risk-of-bias tool for randomized trials 2.0A was employed for quality assessment. RESULTS: Among 351 screened studies, 7 met the criteria, totaling 356 participants (WBV group, n = 182; control group, n = 174). Meta-analysis revealed a significant mean difference of 41.36 m [95%CI (13.28-69.44); p = .004] in the 6-minute walk test distance favoring the WBV group for functional capacity. Lower limb muscle strength improved in 57.14% of included studies. HRQoL meta-analysis demonstrated a 1.13-point difference [95%CI -1.24-3.51; p = .35] favoring WBV, although group differences were not significant. A mean difference of 2.31 points favored the control group in health condition [95%CI (-1.32-5.94); p = .021]. CONCLUSION: WBV exercise is recognized as a promising therapeutic modality for severe COPD patients, notably enhancing functional capacity. Although heterogeneous study protocols weaken the evidence for clinically relevant outcomes, improvements in lower limb muscle strength and HRQoL were also observed, differences between groups were not significant.
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Obesity is a major health burden worldwide. Although bariatric surgery (BS) is recognized as an effective strategy for weight loss and comorbidities improvement, its impact on muscle strength and quality is still unclear. We aimed to examine postoperative changes in muscle strength and quality and their relationship with body mass index (BMI) changes among adults undergoing BS. To this end, we systematically searched the WoS, PubMed, EBSCO, and Scopus databases. The meta-analyses, which included 24 articles (666 participants), showed that BS reduces absolute lower-limb isometric strength (ES = -0.599; 95% CI = -0.972, -0.226; p = 0.002). Subjects who experienced a more significant reduction in BMI after BS also suffered a higher loss of absolute muscle strength. Similarly, absolute handgrip strength showed a significant decrease (ES = -0.376; 95% CI = -0.630, -0.121; p = 0.004). We found insufficient studies investigating medium- and long-term changes in muscle strength and/or quality after BS. This study provides moderate-quality evidence that BS-induced weight loss can reduce the strength of appendicular muscles in the short term, which should be addressed in management these subjects. More high-quality studies are needed to evaluate the impact of BS on muscle strength and the different domains of muscle quality in the medium and long term (registered on PROSPERO CRD42022332581).
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Cirurgia Bariátrica , Força Muscular , Humanos , Força Muscular/fisiologia , Redução de Peso/fisiologia , Obesidade/cirurgia , Obesidade/fisiopatologia , Índice de Massa Corporal , Músculo Esquelético/fisiologia , Força da Mão/fisiologiaRESUMO
BACKGROUND & AIMS: Functional muscle quality, as assessed through the muscle quality index (MQI), represents a contemporary method to measure the capacity to generate force. Despite its potential, the prognostic significance of MQI remains uncertain in various clinical conditions, particularly among patients following acute myocardial infarction (AMI). In light of this, our study sought to evaluate the prognostic relevance of MQI concerning major adverse cardiovascular events (MACE) in patients following AMI. METHODS AND RESULTS: This is a secondary analysis of a prospective cohort study that included subjects aged ≥20 years from a Cardiovascular Unit Hospital. Functional muscle quality was estimated using MQI, defined as the ratio of handgrip strength (HGS) to muscle mass (MM) derived from bioelectrical impedance analysis. The outcomes included prolonged length of hospital stay, new adverse cardiovascular events (AMI, stroke and hospital readmission for unstable angina), and cardiovascular mortality. A composite score comprising all adverse events over the 1-year follow-up was calculated and defined as MACE. This study included 163 patients, with a median age of 61 years (IQ: 54-69 years), and the majority consisted of males (76.1%). Individual components of the functional muscle quality (HGS and MM) were not associated with any of the adverse outcomes. Only MQI was associated mortality over the 1-year follow-up. For each increase in MQI, the hazard of mortality decreases: adjusted HR: 0.08 (95% CI 0.01-0.84). CONCLUSION: Functional muscle quality assessed by the MQI may be a valuable clinical predictor of 1-year cardiovascular mortality in patients hospitalized post-AMI.
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Força da Mão , Tempo de Internação , Músculo Esquelético , Infarto do Miocárdio , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/diagnóstico , Idoso , Fatores de Tempo , Medição de Risco , Prognóstico , Fatores de Risco , Músculo Esquelético/fisiopatologia , Readmissão do Paciente , Valor Preditivo dos Testes , Impedância Elétrica , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/diagnóstico , Angina Instável/mortalidade , Angina Instável/fisiopatologia , Angina Instável/diagnósticoAssuntos
Esôfago , Contração Muscular , Força Muscular , Músculo Esquelético , Humanos , Força Muscular/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Esôfago/fisiologia , Esôfago/fisiopatologia , Masculino , Feminino , Adulto , Voluntários Saudáveis , Manometria/métodos , Adulto JovemRESUMO
Murine models lacking CLOCK/BMAL1 proteins in skeletal muscle (SkM) present muscle deterioration and mitochondria abnormalities. It is unclear whether humans with lower levels of these proteins in the SkM have similar alterations. Here we evaluated the association between BMAL1 and CLOCK protein mass with mitochondrial dynamics parameters and molecular and functional SkM quality markers in males. SkM biopsies were taken from the vastus lateralis of 16 male (non-athletes, non-obese and non-diabetic) subjects (8-9 a.m.). The morphology of mitochondria and their interaction with the sarcoplasmic reticulum (mitochondria-SR) were determined using transmission electron microscopy images. Additionally, protein abundance of the OXPHOS complex, mitochondria fusion/fission regulators, mitophagy and signalling proteins related to muscle protein synthesis were measured. To evaluate the quality of SkM, the cross-sectional area and maximal SkM strength were also measured. The results showed that BMAL1 protein mass was positively associated with mitochondria-SR distance, mitochondria size, mitochondria cristae density and mTOR protein mass. On the other hand, CLOCK protein mass was negatively associated with mitochondria-SR interaction, but positively associated with mitochondria complex III, OPA1 and DRP1 protein mass. Furthermore, CLOCK protein mass was positively associated with the protein synthesis signalling pathway (total mTOR, AKT and P70S6K protein mass) and SkM strength. These findings suggest that the BMAL1 and CLOCK proteins play different roles in regulating mitochondrial dynamics and SkM function in males, and that modulation of these proteins could be a potential therapeutic target for treating muscle diseases. KEY POINTS: In murine models, reductions in BMAL1 and CLOCK proteins lead to changes in mitochondria biology and a decline in muscle function. However, this association has not been explored in humans. We found that in human skeletal muscle, a decrease in BMAL1 protein mass is linked to smaller intermyofibrillar mitochondria, lower mitochondria cristae density, higher interaction between mitochondria and sarcoplasmic reticulum, and reduced mTOR protein mass. Additionally, we found that a decrease in CLOCK protein mass is associated with a higher interaction between mitochondria and sarcoplasmic reticulum, lower protein mass of OPA1 and DRP1, which regulates mitochondria fusion and fission, lower protein synthesis signalling pathway (mTOR, AKT and P70S6K protein mass), and decreased skeletal muscle strength. According to our findings in humans, which are supported by previous studies in animals, the mitochondrial dynamics and skeletal muscle function could be regulated differently by BMAL1 and CLOCK proteins. As a result, targeting the modulation of these proteins could be a potential therapeutic approach for treating muscle diseases and metabolic disorders related to muscle.
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The aim of this systematic review was to assess the effects of plyometric-jump training (PJT) on the physical fitness of youth with cerebral palsy (CP) compared with controls (i.e., standard therapy). The PRISMA 2020 guidelines were followed. Eligibility was assessed using the PICOS approach. Literature searches were conducted using the PubMed, Web of Science, and SCOPUS databases. Methodological study quality was assessed using the PEDro scale. Data were meta-analyzed by applying a random-effects model to calculate Hedges' g effect sizes (ES), along with 95% confidence intervals (95% CI). The impact of heterogeneity was assessed (I2 statistic), and the certainty of evidence was determined using the GRADE approach. Eight randomized-controlled studies with low-to-moderate methodological quality were included, involving male (n = 225) and female (n = 138) youth aged 9.5 to 14.6 years. PJT interventions lasted between 8 and 12 weeks with 2-4 weekly sessions. Compared with controls, PJT improved the muscle strength (ES = 0.66 [moderate], 95% CI = 0.36-0.96, p < 0.001, I2 = 5.4%), static (ES = 0.69 [moderate], 95% CI= 0.33-1.04, p < 0.001, I2 = 0.0%) and dynamic balance (ES = 0.85 [moderate], 95% CI = 0.12-1.58, p = 0.023, I2 = 81.6%) of youth with CP. Therefore, PJT improves muscle strength and static and dynamic balance in youth with CP compared with controls. However, more high-quality randomized-controlled trials with larger sample sizes are needed to provide a more definitive recommendation regarding the use and safety of PJT to improve measures of physical fitness.
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AIM: This study aimed to investigate the associations between upper- and lower-limb muscle strength, mass, and quality and health-related quality of life (HRQoL) among community-dwelling older adults. METHODS: A cross-sectional study was conducted with 428 Brazilian community-dwelling older adults aged 60 to 80 years. Upper- and lower-limb muscle strength were evaluated through the handgrip strength (HGS) test and the 30-s chair stand test, respectively. Muscle mass was assessed by dual-energy X-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA). Muscle quality was evaluated using the muscle quality index (MQI). HRQoL was assessed using the World Health Organization Quality of Life Brief Version questionnaire. RESULTS: Lower-limb, but not upper-limb, muscle strength and quality were independently associated with HRQoL, particularly within the domains of physical capacity, environment, and overall HRQoL for both males and females (P < 0.05). DXA- and BIA-derived analyses provided similar results in relation to muscle mass and muscle quality. CONCLUSIONS: Lower-limb, but not upper-limb, muscle strength and quality were independently associated with HRQoL among community-dwelling older adults. Moreover, the results obtained from both BIA and DXA were similar, highlighting that BIA can serve as a viable surrogate method for estimating body composition in resource-limited clinical settings. Geriatr Gerontol Int 2024; 24: 683-692.
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Vida Independente , Extremidade Inferior , Força Muscular , Qualidade de Vida , Extremidade Superior , Humanos , Idoso , Masculino , Feminino , Estudos Transversais , Força Muscular/fisiologia , Idoso de 80 Anos ou mais , Extremidade Superior/fisiologia , Brasil , Extremidade Inferior/fisiologia , Pessoa de Meia-Idade , Absorciometria de Fóton , Força da Mão/fisiologia , Impedância Elétrica , Avaliação Geriátrica/métodos , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: We investigated the accuracy of the 10-item Physical Function (PF-10) questions of the SF-36 quality of life questionnaire as a sarcopenia screening tool among patients on hemodialysis. METHODS: A cross-sectional, multicenter study that included adult patients on hemodialysis. The revised European Working Group on Sarcopenia in Older People was used to diagnose sarcopenia. The 10 questions about daily activities from the SF-36 quality of life questionnaire were used to appoint the PF-10, where the final score could range from 10 to 30, and the lower the worse the physical function. The PF-10 accuracy to identify confirmed sarcopenia (low muscle strength + low muscle mass) was assessed through a receiver operating characteristic curve and the cutoff was calculated using the Youden index. RESULTS: One hundred eighty-five patients were included (median 59 years; 45% female). Prevalence of confirmed sarcopenia was 31.4%. The median PF-10 score was 23 (interquartile range: 17-27) and a significant association with all sarcopenia measurements was found (all P < .05). The best cutoff calculated from the receiver operating characteristic curve was ≤26 points (area under the curve = 0.69, 95% confidence interval 0.61-0.77) with sensitivity and specificity of 96.6% and 71.0%, respectively. Moreover, patients with ≤26 points (n = 133, 72%) had a higher prevalence of low muscle strength by handgrip (53 vs. 19%; P < .001) and 5-time sit-to-stand (41 vs. 10%; P < .001), low gait speed (44 vs. 19%; P = .002), confirmed sarcopenia (39 vs. 11%; P < .001), and severe sarcopenia (26 vs. 4%; P = .001), but not low muscle mass (49 vs. 35%; P = .08), in comparison with those >26 points (n = 52, 28%). CONCLUSION: The PF-10 may be a useful physical dysfunction and sarcopenia screening tool in patients on hemodialysis. A PF-10 threshold of around 26 points appeared to display the fairest accuracy for diagnosing sarcopenia.
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PURPOSE: to explore lower limb muscle activity concerning limb dominance, as well as variations in force and power during the standing up and sitting down phases of the instrumented sit-to-stand-to-sit test in sedentary individuals, across isokinetic and isotonic modalities. METHODS: 33 sedentary individuals underwent testing using a functional electromechanical dynamometer in both isokinetic and isotonic modes, accompanied by surface electromyography. RESULTS: In the isokinetic mode, the non-dominant gastrocnemius medialis and vastus medialis exhibited significantly (p < 0.05) higher muscle activity values during the standing up and sitting down phase compared to dominant counterparts. In the isotonic mode standing up phase, significant differences in muscle activity were noted for non-dominant gastrocnemius medialis, vastus medialis, and biceps femoris compared to their dominant counterparts. The sitting down phase in isotonic mode showed higher muscle activity for non-dominant vastus medialis compared to dominant vastus medialis. Regard to performance outcomes, significantly lower (p < 0.0001) values were observed for standing up (12.7 ± 5.1 N/kg) compared to sitting down (15.9 ± 6.1 N/kg) peak force, as well as for standing up (18.7 ± 7.8 W/kg) compared to sitting down (25.9 ± 9.7 W/kg) peak power in isokinetic mode. In isotonic mode, lower values were found for sitting down (6.5 (6.3-7.1) N/kg) compared to standing up (7.8 (7.3-8.9) N/kg) peak force and for sitting down (18.5 (13.2-21.7) W/kg) compared to standing up (33.7 (22.8-41.6) W/kg) peak power. CONCLUSIONS: Limb dominance influences lower-limb muscle activity during the instrumented sit-to-stand-to-sit test, and the choice of testing mode (isokinetic or isotonic) affects muscle engagement and performance outcomes.
Assuntos
Eletromiografia , Extremidade Inferior , Músculo Esquelético , Comportamento Sedentário , Humanos , Masculino , Músculo Esquelético/fisiologia , Adulto , Feminino , Extremidade Inferior/fisiologia , Adulto Jovem , Lateralidade Funcional/fisiologia , Postura Sentada , Força Muscular/fisiologiaRESUMO
INTRODUCTION: Chronic venous disease (CVD) is a highly prevalent disease that presents a wide spectrum of clinical expressions due to abnormalities in the venous system. Patients often have major functional changes that can limit daily activities. However, the functional factors associated with the severity of the disease remain poorly understood. OBJECTIVE: To identify the functional factors associated with CVD severity. METHODS: Seventy-five patients with CVD (92.0% females, 49.6 ± 13.3 years) were evaluated through clinical examination, lower limb perimetry, ankle range of motion (AROM), and lower limb muscle strength by the Heel Rise test, and Sit-to-stand test. Patients were stratified according to the disease severity as mild (telangiectasia, varicose veins, or edema in the lower limbs) or severe CVD (trophic changes or venous ulcer). RESULTS: Patients with severe CVD (n = 13) were older (p = 0.002), predominantly male (p = 0.007), with reduced AROM in dorsiflexion (p = 0.028) and inversion (p = 0.009), reduced lower limb strength by the Heel Rise test (p = 0.040), and greater circumference of the calf (p = 0.020), ankle (p = 0.003), and plantar arch (p = 0.041) when compared to mild CVD (n = 62). Advanced age, male sex, lower ankle range of motion in dorsiflexion, and greater ankle and plantar arch circumferences were associated with CVD severity. However, the ankle circumference (OR 1.258, 95% CI: 1.008-1.570; p = 0.042), together with advanced age and male sex, was the only functional variable that remained independently associated with CVD severity. CONCLUSION: The increased ankle circumference was a determinant of the CVD severity and may assist in risk stratification and guide treatment goals in this population.