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1.
J Mech Behav Biomed Mater ; 157: 106631, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38986216

RESUMEN

Fall-related hip fractures are a serious public health issue in older adults. As most mechanistic hip fracture risk prediction models incorporate tissue tolerance, test methods that can accurately characterize the fracture force of the femur (and factors that influence it) are imperative. While bone possesses viscoelastic properties, experimental characterization of rate-dependencies has been inconsistent in the whole-femur literature. The goal of this study was to investigate the influence of experimental paradigm on loading rate and fracture force (both means and variability) during mechanical tests simulating lateral fall loadings on the proximal femur. Six pairs of matched femurs were split randomly between two test paradigms: a 'lower rate' materials testing system (MTS) with a constant displacement rate of 60 mm/s, and a hip impact test system (HIT) comprised of a custom-built vertical drop tower utilizing an impact velocity of 4 m/s. The loading rate was 88-fold higher for the HIT (mean (SD) = 2465.49 (807.38) kN/s) compared to the MTS (27.78 (10.03) kN/s) paradigm. However, no difference in fracture force was observed between test paradigms (mean (SD) = 4096.4 (1272.6) N for HIT, and 3641.3 (1285.8) N for MTS). Within-paradigm variability was not significantly different across paradigms for either loading rate or fracture force (coefficients of variation ranging from 0.311 to 0.361). Within each test paradigm, significant positive relationships were observed between loading rate and fracture force (HIT adjusted R2 = 0.833, p = 0.007; MTS adjusted R2 = 0.983, p < 0.0001). Overall, this study provides evidence that energy-based impact simulators can be a valid method to measure femoral bone strength in the context of fall-related hip fractures. This study motivates future research to characterize potential non-linear relationships between loading rate and fracture threshold at both macro and microscales.


Asunto(s)
Accidentes por Caídas , Fémur , Ensayo de Materiales , Soporte de Peso , Humanos , Fémur/fisiología , Anciano , Masculino , Pruebas Mecánicas , Femenino , Fenómenos Biomecánicos , Fracturas del Fémur/fisiopatología , Anciano de 80 o más Años , Estrés Mecánico , Fracturas Femorales Proximales
2.
Artículo en Inglés | MEDLINE | ID: mdl-39073365

RESUMEN

BACKGROUND: Body composition may be related to survival in clear cell renal cell carcinoma (ccRCC) patients but studies have not simultaneously considered adipose and muscle tissue quantity and radiodensity. METHODS: We analyzed data from 1,022 ccRCC patients who underwent nephrectomy between 2000 -2020 at Memorial Sloan Kettering Cancer Center. Skeletal muscle, visceral adipose, and subcutaneous adipose tissue index (SMI, VATI, SATI respectively; cm2/m2) and radiodensity (SMD, VATD, SATD respectively; Hounsfield Units [HU]) were assessed from non-contrast pre-surgical computed tomography scans; clinical and demographic characteristics were available from the time of surgery. Hazard ratios (HR) and confidence intervals (CI) were estimated for overall (OS) and disease-free survival (DFS) through March 2023 in multivariable models that simultaneously accounted for all body composition measures. RESULTS: Median age was 58 years, 69% were male, and 90% White. There were 169 OS events over 8,392 person-years, and 253 DFS events over 7,753 person-years of follow-up. In adjusted analyses, poor OS was associated with lower SMD (-10 HU, HR (95% CI): 1.37 [1.05, 1.77]), and greater VATD (+10 HU: 1.66 [1.06, 2.59]), with similar findings for DFS. Poor survival was also associated with greater VATI (+40 cm2/m2, OS: 1.32 [0.97, 1.79]; DFS: 1.33 [1.04, 1.71]). Associations with SMD were limited to patients with stage 1/2 disease. CONCLUSIONS: Radiodensities of skeletal muscle and visceral adipose tissue may be novel pre-surgical prognostic factors for ccRCC patients. IMPACT: Findings underscore the importance of evaluating the full range of body composition features simultaneously in multivariable models.

3.
J Biomech ; 172: 112213, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38968649

RESUMEN

Hip fractures are a severe health concern among older adults. While anthropometric factors have been shown to influence hip fracture risk, the low fidelity of common body composition metrics (e.g. body mass index) reduces our ability to infer underlying mechanisms. While simulation approaches can be used to explore how body composition influences impact dynamics, there is value in experimental data with human volunteers to support the advancement of computational modeling efforts. Accordingly, the goal of this study was to use a novel combination of subject-specific clinical imaging and laboratory-based impact paradigms to assess potential relationships between high-fidelity body composition and impact dynamics metrics (including load magnitude and distribution and pelvis deflection) during sideways falls on the hip in human volunteers. Nineteen females (<35 years) participated. Body composition was assessed via DXA and ultrasound. Participants underwent low-energy (but clinically relevant) sideways falls on the hip during which impact kinetics (total peak force, contract area, peak pressure) and pelvis deformation were measured. Pearson correlations assessed potential relationships between body composition and impact characteristics. Peak force was more strongly correlated with total mass (r = 0.712) and lean mass indices (r = 0.510-0.713) than fat mass indices (r = 0.401-0.592). Peak deflection was positively correlated with indices of adiposity (all r > 0.7), but not of lean mass. Contact area and peak pressure were positively and negatively associated, respectively, with indices of adiposity (all r > 0.49). Trochanteric soft tissue thickness predicted 59 % of the variance in both variables, and was the single strongest correlate with peak pressure. In five-of-eight comparisons, hip-local (vs. whole body) anthropometrics were more highly associated with impact dynamics. In summary, fall-related impact dynamics were strongly associated with body composition, providing support for subject-specific lateral pelvis load prediction models that incorporate soft tissue characteristics. Integrating soft and skeletal tissue properties may have important implications for improving the biomechanical effectiveness of engineering-based protective products.


Asunto(s)
Composición Corporal , Tamaño Corporal , Fracturas de Cadera , Humanos , Femenino , Composición Corporal/fisiología , Adulto , Tamaño Corporal/fisiología , Fracturas de Cadera/fisiopatología , Accidentes por Caídas , Cadera/fisiología , Fenómenos Biomecánicos
4.
Nutrition ; 125: 112494, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38843564

RESUMEN

BACKGROUND AND AIMS: Measurement of body composition using computed tomography (CT) scans may be a viable clinical tool for low muscle mass assessment in oncology. However, longitudinal assessments are often infeasible with CT. Clinically accessible body composition technologies can be used to track changes in fat-free mass (FFM) or muscle, though their accuracy may be impacted by cancer-related physiological changes. The purpose of this study was to examine the agreement among accessible body composition method with criterion methods for measures of whole-body FFM measurements and, when possible, muscle mass for the classification of low muscle in patients with cancer. METHODS: Patients with colorectal cancer were recruited to complete measures of whole-body DXA, air displacement plethysmography (ADP), and bioelectrical impedance analysis (BIA). These measures were used alone, or in combination to construct the criterion multicompartment (4C) mode for estimating FFM. Patients also underwent abdominal CT scans as part of routine clinical assessment. Agreement of each method with 4C model was analyzed using mean constant error (CE = criterion - alternative), linear regression including root mean square error (RMSE), Bland-Altman limits of agreement (LoA) and mean percentage difference (MPD). Additionally, appendicular lean soft tissue index (ALSTI) measured by DXA and predicted by CT were compared for the absolute agreement, while the ALSTI values and skeletal muscle index by CT were assessed for agreement on the classification of low muscle mass. RESULTS: Forty-five patients received all measures for the 4C model and 25 had measures within proximity of clinical CT measures. Compared to 4C, DXA outperformed ADP and BIA by showing the strongest overall agreement (CE = 1.96 kg, RMSE = 2.45 kg, MPD = 98.15 ± 2.38%), supporting its use for body composition assessment in patients with cancer. However, CT cutoffs for skeletal muscle index or CT-estimated ALSTI were lower than DXA ALSTI (average 1.0 ± 1.2 kg/m2) with 24.0% to 32.0% of patients having a different low muscle classification by CT when compared to DXA. CONCLUSIONS: Despite discrepancies between clinical body composition assessment and the criterion multicompartment model, DXA demonstrates the strongest agreement with 4C. Disagreement between DXA and CT for low muscle mass classification prompts further evaluation of the measures and cutoffs used with each technique. Multicompartment models may enhance our understanding of body composition variations at the individual patient level and improve the applicability of clinically accessible technologies for classification and monitoring change over time.


Asunto(s)
Absorciometría de Fotón , Composición Corporal , Neoplasias Colorrectales , Impedancia Eléctrica , Músculo Esquelético , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Persona de Mediana Edad , Absorciometría de Fotón/métodos , Anciano , Tomografía Computarizada por Rayos X/métodos , Neoplasias Colorrectales/diagnóstico por imagen , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/fisiopatología , Pletismografía/métodos , Adulto
5.
J Cachexia Sarcopenia Muscle ; 15(2): 726-734, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38263932

RESUMEN

INTRODUCTION: Most studies on body composition in kidney cancer have been conducted among patients with metastatic disease. Given that aggressive tumours can adversely impact body composition and even non-metastatic tumours can be aggressive, we evaluated associations between pre-surgical body composition features and tumour pathological features in patients with non-metastatic clear cell renal cell cancer (ccRCC). METHODS: The Resolve Cohort consists of 1239 patients with non-metastatic ccRCC who underwent nephrectomy at Memorial Sloan Kettering Cancer Center between 2000 and 2020. The cross-sectional areas and radiodensities of skeletal muscle, visceral adipose, and subcutaneous adipose tissues were determined from pre-surgical computed tomography (CT) scans at the third lumbar vertebrae using Automatica software. Pearson's correlation coefficients describe inter-relationships among BMI and body composition variables, while odds ratios (OR) and 95% confidence intervals (CI) estimate associations between continuous body composition features (per 1-standard deviation) and advanced stage (Stage III vs. Stages I-II) and high Fuhrman grade (Grades 3-4 vs. 1-2) from multivariable logistic regression models that considered the potential impact of biological sex, contrast enhanced CTs, and early age at onset of ccRCC. RESULTS: The cohort was predominantly male (69%), white (89%), and had a median age of 58. The proportion of patients presenting with advanced stage and high-grade disease were 31% and 51%, respectively. In models that adjusted for demographics and all body composition variables simultaneously, decreasing skeletal muscle radiodensity (i.e., more fat infiltration) but increasing visceral adipose tissue radiodensity (i.e., more lipid depletion) were associated with advanced tumour features. Per 8.4 HU decrease in skeletal muscle radiodensity, the odds of presenting with advanced stage was 1.61 (95% CI: 1.34-1.93). Per 7.22 HU increase in visceral adipose tissue radiodensity, the odds of presenting with advanced stage was 1.45 (95% CI: 1.22-1.74). Skeletal muscle index (i.e., sarcopenia) was not associated with either tumour feature. Similar associations were observed for Fuhrman grade, a more direct marker of tumour aggressiveness. Associations did not differ by sex, contrast use, or age at onset of ccRCC. CONCLUSIONS: Lipid infiltrated skeletal muscle, but lipid depleted visceral adipose tissue were independently associated with advanced tumour features in non-metastatic ccRCC. Findings highlight the importance of evaluating the full range of body composition features simultaneously in multivariable models. Interpreting pre-surgical CTs for body composition for patients may be a novel and non-invasive way to identify patients with aggressive renal tumours, which is clinically relevant as renal biopsies are not routinely performed.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Sarcopenia , Humanos , Masculino , Femenino , Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/patología , Sarcopenia/patología , Lípidos
6.
Phys Ther ; 103(10)2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37669136

RESUMEN

OBJECTIVE: The purpose of this trial is to evaluate the effect of twice-weekly, moderate-to-high intensity progressive resistance training (PRT) for 1 year on lumbar spine bone mineral density (BMD) in individuals with low BMD, compared to attention control. Secondary analyses will examine if resistance training improves other health outcomes; if high intensity is more effective than moderate intensity resistance training for all outcomes; the cost of intervention versus benefit; the willingness to pay; and harms. METHODS: For this study, 324 men or postmenopausal women aged ≥50 years with a femoral neck, total hip, or lumbar spine BMD T-score of ≤-1, or a Fracture Risk Assessment Tool probability of ≥20% for major osteoporotic fracture or ≥ 3% for hip fracture are being recruited to participate in a randomized controlled trial with 1:1:1 randomization. Participants will be stratified by site (3 centers) to twice-weekly, supervised PRT at moderate intensity (about 10 repetitions maximum), to high intensity PRT (≤6 repetitions maximum), or to a home posture and balance exercise program (attention control) for 1 year (resistance training to comparator allocation ratio of 2:1). The primary outcome is lumbar spine BMD via dual-energy X-ray absorptiometry. Secondary outcomes include trabecular bone score, proximal femur and total hip BMD and structure, bone-free and appendicular lean mass, physical functioning, falls, fractures, glucose metabolism, cost per life-year gained, adverse events, and quality of life. Between-group differences will be tested in intention-to-treat and per-protocol analyses using analysis of covariance, chi-square tests, or negative binomial or logistic regression, adjusting for site and baseline values. IMPACT: The Finding the Optimal Resistance Training Intensity For Your Bones trial will support decision making on resistance training for people at risk of fracture.

7.
J Surg Oncol ; 128(5): 769-780, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37291908

RESUMEN

BACKGROUND & OBJECTIVES: Low muscle mass, measured using computed tomography (CT), is associated with poor surgical outcomes. We aimed to include CT-muscle mass in malnutrition diagnosis using the Global Leadership Initiative on Malnutrition (GLIM) criteria, compare it to the International Classification of Diseases 10th Revision (ICD-10) criteria, and assess the impact on postoperative outcomes after oesophagogastric (OG) cancer surgery. METHODS: One hundred and eight patients who underwent radical OG cancer surgery and had preoperative abdominal CT imaging were included. GLIM and ICD-10 malnutrition data were assessed against complication and survival outcomes. Low CT-muscle mass was determined using predefined cut-points. RESULTS: GLIM-defined malnutrition prevalence was significantly higher than ICD-10-malnutrition (72.2% vs. 40.7%, p < 0.001). Of the 78 patients with GLIM-defined malnutrition, low muscle mass (84.6%) was the predominant phenotypic criterion. GLIM-defined malnutrition was associated with pneumonia (26.9% vs. 6.7%, p = 0.010) and pleural effusions (12.8% vs. 0%, p = 0.029). Postoperative complications did not correlate with ICD-10 malnutrition. Severe GLIM (HR: 2.51, p = 0.014) and ICD-10 (HR: 2.15, p = 0.039) malnutrition were independently associated with poorer 5-year survival. CONCLUSIONS: GLIM criteria appear to identify more malnourished patients and more closely relate to surgical risk than ICD-10 malnutrition, likely due to incorporating objective muscle mass assessment.


Asunto(s)
Desnutrición , Neoplasias , Humanos , Clasificación Internacional de Enfermedades , Incidencia , Liderazgo , Desnutrición/diagnóstico , Desnutrición/epidemiología , Evaluación Nutricional , Estado Nutricional
8.
J Appl Biomech ; 39(4): 217-222, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37225172

RESUMEN

Breast cancer affects one in 8 females with a 5-year survival rate of 89%. Up to 72% of breast cancer survivors have trouble with activities of daily living (ADL) following treatment. Increased time-from-treatment improves some measures of function, yet ADL limitations persist. Therefore, this study assessed the effect of time-from-treatment on upper extremity kinematics during ADLs in breast cancer survivors. Twenty-nine female breast cancer survivors were divided into 2 groups: <1 year (n = 12) and 1-2 years (n = 17) from treatment. Kinematics were collected during 6 ADL tasks, and humerothoracic joint angles were quantified. A 2-way mixed analysis of variance assessed the effects of time-from-treatment and arm on maximum angles for each ADL. Decreased maximum angle existed for breast cancer survivors with increased time-from-treatment during all ADLs. Breast cancer survivors in the 1-2 years group used ∼28° to 32° lower elevation, ∼14° to 28° lower axial rotation, and ∼10° to 14° lower plane of elevation range across tasks. Decreased ranges of arm movement during ADLs with increased time-from-treatment may reflect compensatory movement strategies. Recognizing this shift in strategies and accompanying underlying disease progression can help inform responses to functional performance limitations in breast cancer survivors as delayed effects are present posttreatment.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Humanos , Femenino , Actividades Cotidianas , Fenómenos Biomecánicos , Extremidad Superior , Rango del Movimiento Articular
9.
Appl Physiol Nutr Metab ; 48(6): 427-435, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36848646

RESUMEN

The objective of this study was to explore the experiences and perspectives of individuals with chronic health conditions who had an adverse event (AE) as a result of resistance training (RT). We conducted web conference or telephone-based one-on-one semi-structured interviews with 12 participants with chronic health conditions who had an AE as a result of RT. Interview data were analyzed using the thematic framework method. Six themes were identified: (1) personal experiences with aging influence perceptions of RT; (2) physical and emotional consequences of AEs limit activities and define future RT participation; (3) injury recovery defines the severity of AE; (4) health conditions influence the perceived risks and benefits of participating in RT; (5) RT setting and trained supervision influence exercise behaviors and risk perceptions; and (6) experiencing a previous AE influences future exercise behavior. Despite participant awareness of the value and benefits of RT in both the context of aging and chronic health conditions, there is concern about experiencing exercise-related AEs. The perceived risks of RT influenced the participants' decision to engage or return to RT. Consequently, to promote RT participation, the risks, not just the benefits, should be properly reported in future studies, translated, and disseminated to the public. Novelty: -To increase the quality of published research with respect to AE reporting in RT studies. -Health care providers and people with common health conditions will be able to make evidence-based decisions as to whether the benefits of RT truly outweigh the risks.


Asunto(s)
Entrenamiento de Fuerza , Humanos , Entrenamiento de Fuerza/efectos adversos , Ejercicio Físico , Enfermedad Crónica
10.
Crit Care Med ; 51(2): e24-e36, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36661463

RESUMEN

OBJECTIVE: Significant variations exist in the use of respiratory muscle ultrasound in intensive care with no society-level consensus on the optimal methodology. This systematic review aims to evaluate, synthesize, and compare the clinimetric properties of different image acquisition and analysis methodologies. DATA SOURCES: Systematic search of five databases up to November 24, 2021. STUDY SELECTION: Studies were included if they enrolled at least 50 adult ICU patients, reported respiratory muscle (diaphragm or intercostal) ultrasound measuring either echotexture, muscle thickness, thickening fraction, or excursion, and evaluated at least one clinimetric property. Two independent reviewers assessed titles, abstracts, and full text against eligibility. DATA EXTRACTION: Study demographics, ultrasound methodologies, and clinimetric data. DATA SYNTHESIS: Sixty studies, including 5,025 patients, were included with 39 studies contributing to meta-analyses. Most commonly measured was diaphragm thickness (DT) or diaphragm thickening fraction (DTF) using a linear transducer in B-mode, or diaphragm excursion (DE) using a curvilinear transducer in M-mode. There are significant variations in imaging methodology and acquisition across all studies. Inter- and intrarater measurement reliabilities were generally excellent, with the highest reliability reported for DT (ICC, 0.98; 95% CI, 0.94-0.99). Pooled data demonstrated acceptable to excellent accuracy for DT, DTF, and DE to predicting weaning outcome after 48 to 72 hours postextubation (DTF AUC, 0.79; 95% CI, 0.73-0.85). DT imaging was responsive to change over time. Only three eligible studies were available for intercostal muscles. Intercostal thickening fraction was shown to have excellent accuracy of predicting weaning outcome after 48-hour postextubation (AUC, 0.84; 95% CI, 0.78-0.91). CONCLUSIONS: Diaphragm muscle ultrasound is reliable, valid, and responsive in ICU patients, but significant variation exists in the imaging acquisition and analysis methodologies. Future work should focus on developing standardized protocols for ultrasound imaging and consider further research into the role of intercostal muscle imaging.


Asunto(s)
Diafragma , Desconexión del Ventilador , Adulto , Humanos , Desconexión del Ventilador/métodos , Reproducibilidad de los Resultados , Ultrasonografía/métodos , Diafragma/diagnóstico por imagen , Cuidados Críticos
11.
Clin Cancer Res ; 28(23): 5180-5189, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36190538

RESUMEN

PURPOSE: High body mass index (BMI) may lead to improved immune-checkpoint blockade (ICB) outcomes in metastatic clear cell renal cell carcinoma (mccRCC). However, BMI is a crude body size measure. We investigated BMI and radiographically assessed body composition (BC) parameters association with mccRCC ICB outcomes. EXPERIMENTAL DESIGN: Retrospective study of ICB-treated patients with mccRCC. BMI and BC variables [skeletal muscle index (SMI) and multiple adiposity indexes] were determined using pretreatment CT scans. We examined the associations between BMI and BC variables with ICB outcomes. Therapeutic responses per RECIST v1.1 were determined. We compared whole-transcriptomic patterns with BC variables in a separate cohort of 62 primary tumor samples. RESULTS: 205 patients with mccRCC were included in the cohort (74% were male, 71% were overweight/obese, and 53% were classified as low SMI). High-BMI patients experienced longer overall survival (OS) than normal-weight patients [unadjusted HR, 0.66; 95% confidence interval (CI), 0.45-0.97; P = 0.035]. The only BC variable associated with OS was SMI [unadjusted HR comparing low vs. high SMI 1.65 (95% CI: 1.13-2.43); P = 0.009]. However, this OS association became nonsignificant after adjusting for International Metastatic Renal Cell Carcinoma Database Consortium score and line of therapy. No OS association was seen for adiposity and no BC variable was associated with progression-free survival or radiological responses. Tumors from patients with low SMI displayed increased angiogenic, inflammatory, and myeloid signals. CONCLUSIONS: Our findings highlight the relevance of skeletal muscle in the BMI paradox. Future studies should investigate if addressing low skeletal muscle in metastatic patients treated with ICB can improve survival.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Masculino , Femenino , Carcinoma de Células Renales/patología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Renales/patología , Estudios Retrospectivos , Obesidad/complicaciones , Obesidad/tratamiento farmacológico , Composición Corporal
12.
Appl Physiol Nutr Metab ; 47(12): 1172-1186, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36108334

RESUMEN

Exercise and nutrition interventions are often recommended for frailty; however, effective strategies are required for real-world implementation. Our primary aim was to assess the feasibility and acceptability of telephone and virtual delivery of MoveStrong, an 8-week exercise and nutrition program with a 4-week follow-up for older pre-frail and frail adults. A priori criteria for success included: recruitment (≥25/12 weeks), retention at follow-up (≥80%), and adherence to exercise and nutrition sessions (≥70%). We recruited community-dwelling Ontario residents; ≥60 years, ≥1 chronic condition, ≥1 FRAIL scale score. Participants received mailed materials, a personalized exercise program, 11 remote one-on-one training sessions with an exercise physiologist and 3 online dietitian-led nutrition education sessions. We completed exploratory analyses of secondary outcomes including physical function and dietary protein intake. Semi-structured interviews supported program evaluation. In total, 30 participants were enrolled. 28 (93%) participants completed program and follow-up assessments. Adherence to exercise and nutrition sessions (CI) was 84% (77%-91%) and 82% (70%-93%) respectively. At program end and follow-up [mean change (CI)], significant improvements were measured in 30-second chair stand test [3.50 (1.12-5.86), 4.54 (1.94-7.13) chair stands] and dietary protein intake [12.9 (5.7-20.0), 9.2 (0.4-18.1) g]. Overall, participants were satisfied with program delivery. Trial registration number: NCT04663685.


Asunto(s)
Anciano Frágil , Fragilidad , Humanos , Anciano , Estudios de Factibilidad , Terapia por Ejercicio , Proteínas en la Dieta
13.
J Biomech ; 141: 111192, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35764013

RESUMEN

Metrics of femur geometry and body composition have been linked to clinical hip fracture risk. Mechanistic explanations for these relationships have generally focused on femur strength; however, impact loading also modulates fracture risk. We evaluated the potential effects of femur geometry and body composition on femoral neck stresses during lateral impacts. Fifteen female volunteers completed low-energy sideways falls on to the hip. Additionally, participants completed ultrasound and dual-energy x-ray absorptiometry imaging to characterize trochanteric soft tissue thickness (TSTT) over the hip and six metrics of femur geometry, respectively. Subject-specific beam models were developed and utilized to calculate peak femoral neck stress (σNeck), utilizing experimental impact dynamics. Except for femoral neck axis length, all metrics of femur geometry were positively correlated with σNeck (all p < 0.05). Larger/more prominent proximal femurs were associated with increased force over the proximal femur, whereas a wider neck-shaft angle was associated with greater stress generation independent of force (all p < 0.05). Body mass index (BMI) and TSTT were negatively correlated with σNeck (both p < 0.05). Despite strong correlations, these metrics of body composition appear to influence femoral neck stresses through different mechanisms. Increased TSTT was associated with reduced force over the proximal femur, whereas increased BMI was associated with greater resistance to stress generation (both p < 0.05). This study provided novel insights into the mechanistic pathways through which femur geometry and body composition may modulate hip fracture risk. Our findings complement clinical findings and provide one possible explanation for incongruities in the clinical fracture risk and femur strength literature.


Asunto(s)
Cuello Femoral , Fracturas de Cadera , Absorciometría de Fotón/métodos , Composición Corporal , Densidad Ósea , Femenino , Fémur , Cuello Femoral/diagnóstico por imagen , Humanos
14.
Health Promot Chronic Dis Prev Can ; 42(6): 238-251, 2022 Jun.
Artículo en Inglés, Francés | MEDLINE | ID: mdl-35766913

RESUMEN

BACKGROUND: This 8-week pilot stepped-wedge randomized controlled trial evaluated the MoveStrong program for teaching adults who have frailty/pre-frailty about balance and functional strength training and sufficient protein intake to prevent falls and improve mobility. METHODS: We recruited individuals aged 60 years and over, with a FRAIL scale score of 1 or higher and at least one chronic condition, who were not currently strength training. The program included 16 exercise physiologist-led hour-long group sessions and two dietitian-led hour-long nutrition sessions. We analyzed secondary outcomes-weight, gait speed, grip strength, physical capacity (fatigue levels), sit-to-stand functioning, dynamic balance, health-related quality of life (HRQoL), physical activity levels and protein intake-using a paired t test and a generalized estimating equation (GEE). RESULTS: Of 44 participants (mean [SD] age 79 [9.82] years), 35 were pre-frail and 9 were frail. At follow-up, participants had significantly improved grip strength (1.63 kg, 95% CI: 0.62 to 2.63); sit-to-stand functioning (2 sit-to-stands, 95% CI: 1 to 3); and dynamic balance (1.68 s, 95% CI: 0.47 to 2.89). There were no significant improvements in gait speed, HRQoL index scores, self-rated health, physical activity levels (aerobic activity and strength training) or protein intake. GEE analysis revealed an interaction between exposure to MoveStrong and gait speed, sit-to-stand functioning, dynamic balance and HRQoL index scores. The total cost to administer the program and purchase equipment was CAD 14 700, equivalent to CAD 377 per participant. CONCLUSION: Exploratory analyses suggest MoveStrong exercises may improve gait speed, sit-to-stand functioning, dynamic balance and HRQoL index scores in older individuals who are frail and pre-frail.


Asunto(s)
Fragilidad , Anciano , Ejercicio Físico , Terapia por Ejercicio , Fragilidad/prevención & control , Humanos , Persona de Mediana Edad , Proyectos Piloto , Calidad de Vida
15.
Clin Biomech (Bristol, Avon) ; 96: 105666, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35636306

RESUMEN

BACKGROUND: There is a growing number of breast cancer survivors from improved cancer treatments. However, treatments often impair upper limb function, specifically range of motion and strength, reducing quality of life and function. The primary purpose of this study was to quantify differences in strength and range of motion following treatment. The secondary purpose aimed to measure the activation of each upper limb muscle in the completion of tasks. METHODS: 29 breast cancer survivors were categorized into two groups based on time-since-treatment: 1) up to 1-year post-treatment, and 2) 1 to 2 years post-treatment. Participants completed maximal strength and range of motion tasks. During trials eight muscles were monitored bilaterally. Maximal force output was taken during strength trials, and kinematics were monitored during range of motion trials. A 2 by 2 mixed ANOVA (limb (affected, unaffected) x time-since-treatment) examined interaction and main effects of these factors on task peak force, angle and mean activation. FINDINGS: Time-since-treatment influenced strength (flexion, extension, internal and external rotation) and range of motion (flexion, scapular abduction), wherein the group further from treatment had 11.5-15.5° less range of motion and 27.7-43.6 N less force production. A main effect of time-since-treatment influenced muscular behaviours during both tasks, where activation was higher in the group 1-2 years from treatment. INTERPRETATION: Effects of treatment may manifest in a delayed manner whereby strength and range of motion are reduced in breast cancer survivors to a greater extent in those who are past 1 year of treatment cessation.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Articulación del Hombro , Neoplasias de la Mama/terapia , Femenino , Humanos , Calidad de Vida , Rango del Movimiento Articular/fisiología , Extremidad Superior
16.
JPEN J Parenter Enteral Nutr ; 46(6): 1232-1242, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35437785

RESUMEN

The Global Leadership Initiative on Malnutrition (GLIM) provides consensus criteria for the diagnosis of malnutrition that can be widely applied. The GLIM approach is based on the assessment of three phenotypic (weight loss, low body mass index, and low skeletal muscle mass) and two etiologic (low food intake and presence of disease with systemic inflammation) criteria, with diagnosis confirmed by any combination of one phenotypic and one etiologic criterion fulfilled. Assessment of muscle mass is less commonly performed than other phenotypic malnutrition criteria, and its interpretation may be less straightforward, particularly in settings that lack access to skilled clinical nutrition practitioners and/or to body composition methodologies. In order to promote the widespread assessment of skeletal muscle mass as an integral part of the GLIM diagnosis of malnutrition, the GLIM consortium appointed a working group to provide consensus-based guidance on assessment of skeletal muscle mass. When such methods and skills are available, quantitative assessment of muscle mass should be measured or estimated using dual-energy x-ray absorptiometry, computerized tomography, or bioelectrical impedance analysis. For settings where these resources are not available, then the use of anthropometric measures and physical examination are also endorsed. Validated ethnic- and sex-specific cutoff values for each measurement and tool are recommended when available. Measurement of skeletal muscle function is not advised as surrogate measurement of muscle mass. However, once malnutrition is diagnosed, skeletal muscle function should be investigated as a relevant component of sarcopenia and for complete nutrition assessment of persons with malnutrition.


Asunto(s)
Desnutrición , Sarcopenia , Femenino , Humanos , Liderazgo , Masculino , Desnutrición/diagnóstico , Desnutrición/etiología , Músculos , Evaluación Nutricional , Estado Nutricional , Sarcopenia/diagnóstico , Pérdida de Peso
17.
Clin Nutr ; 41(6): 1425-1433, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35450768

RESUMEN

The Global Leadership Initiative on Malnutrition (GLIM) provides consensus criteria for the diagnosis of malnutrition that can be widely applied. The GLIM approach is based on the assessment of three phenotypic (weight loss, low body mass index, and low skeletal muscle mass) and two etiologic (low food intake and presence of disease with systemic inflammation) criteria, with diagnosis confirmed by any combination of one phenotypic and one etiologic criterion fulfilled. Assessment of muscle mass is less commonly performed than other phenotypic malnutrition criteria, and its interpretation may be less straightforward, particularly in settings that lack access to skilled clinical nutrition practitioners and/or to body composition methodologies. In order to promote the widespread assessment of skeletal muscle mass as an integral part of the GLIM diagnosis of malnutrition, the GLIM consortium appointed a working group to provide consensus-based guidance on assessment of skeletal muscle mass. When such methods and skills are available, quantitative assessment of muscle mass should be measured or estimated using dual-energy x-ray absorptiometry, computerized tomography, or bioelectrical impedance analysis. For settings where these resources are not available, then the use of anthropometric measures and physical examination are also endorsed. Validated ethnic- and sex-specific cutoff values for each measurement and tool are recommended when available. Measurement of skeletal muscle function is not advised as surrogate measurement of muscle mass. However, once malnutrition is diagnosed, skeletal muscle function should be investigated as a relevant component of sarcopenia and for complete nutrition assessment of persons with malnutrition.


Asunto(s)
Desnutrición , Estado Nutricional , Femenino , Humanos , Liderazgo , Masculino , Desnutrición/etiología , Prolapso de la Válvula Mitral , Músculo Esquelético , Miopía , Evaluación Nutricional , Enfermedades de la Piel , Pérdida de Peso
18.
Appl Physiol Nutr Metab ; 47(9): 893-902, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35442808

RESUMEN

The objectives of our study were to understand researchers' current practices and perspectives on adverse event (AE) reporting in clinical trials of resistance training (RT) and to identify barriers and facilitators of AE reporting. We conducted web conference or telephone-based one-on-one semistructured interviews with 14 researchers who have published RT studies. We audio-recorded and transcribed the interviews and analyzed the data using the thematic framework method. Four themes were identified: (1) researchers lack guidance and/or motivation for rigorous AE reporting; (2) researchers who undertake AE reporting educate and value participants, use trained personnel, and implement standardized guidelines; (3) suboptimal implementation of existing AE reporting standards and the perception that available guidelines do not apply to exercise trials; and (4) acceptability and feasibility of an exercise-specific guide for AE reporting depend on its content and format. In conclusion, AE reporting methods in the field of exercise science do not align with best practice. Strategies to reduce inconsistent and suboptimal AE reporting in RT trials are urgently needed and could be based on the barriers and facilitators identified in this study.


Asunto(s)
Entrenamiento de Fuerza , Humanos , Investigación Cualitativa , Entrenamiento de Fuerza/efectos adversos
19.
Gait Posture ; 94: 58-66, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35247826

RESUMEN

BACKGROUND: Muscle capacity utilization reflects the percentage of maximal knee extensor strength required to complete physical activities. RESEARCH QUESTION: Is pain associated with muscle capacity utilization during walking in older adults with knee osteoarthritis? Secondarily, is muscle capacity utilization in older adults with knee osteoarthritis sex-specific? METHODS: Twenty-three participants (15 females) with symptomatic knee OA completed this study [age 67 ( ± 8) years, body mass index 29.7 ( ± 3.9) kg/m2, gait speed during the Six Minute Walk test 1.25 ( ± 0.25) m/s]. Pain was measured using the Knee injury and Osteoarthritis Outcome Score. Muscle capacity utilization was quantified as the peak external knee flexor moment during level walking normalized to knee extensor maximum voluntary isometric contraction. The knee flexor moment was calculated from kinematic and kinetic data during barefoot level walking at a self-selected speed and at 1.1 m/s. Knee extensor maximum voluntary isometric contraction was measured on a dynamometer. Multiple linear regressions were used to determine the relationship between pain and muscle capacity utilization after adjusting for age, sex, body mass index, and gait speed. Independent sample t-tests examined sex differences. RESULTS: Pain was not associated with muscle capacity utilization during self-selected and standardized walking speeds (p = 0.38 and p = 0.36, respectively). Females did not require a greater muscle capacity utilization than males to complete gait at self-selected and standardized speeds (p = 0.28, and p = 0.40, respectively). SIGNIFICANCE: Muscle capacity utilization was not associated with pain during walking in people with knee osteoarthritis. Future work should explore more challenging activities of daily living in knee OA.


Asunto(s)
Osteoartritis de la Rodilla , Actividades Cotidianas , Anciano , Femenino , Marcha/fisiología , Humanos , Articulación de la Rodilla , Masculino , Fuerza Muscular , Músculos , Osteoartritis de la Rodilla/complicaciones , Dolor/etiología , Caminata/fisiología
20.
Appl Physiol Nutr Metab ; 47(5): 521-528, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35104155

RESUMEN

Dual-energy X-ray absorptiometry (DXA) appendicular lean tissue is used to screen older adults for sarcopenia. However, emerging data indicates that ageing-related muscle atrophy largely occurs within specific muscles, which may be masked using appendicular lean tissue. Comparisons between appendicular lean tissue and site-specific measures of muscle in relation to strength and physical function are needed to advance our understanding of these features in the context of poor muscle function in aged adults. Our primary objective was to compare correlations between lean tissue and site-specific muscle characteristics in relation to strength and physical function in older males. Older males (≥65 years) were evaluated for muscle strength, physical function (6-minute walk and 30-second sit-to-stand), and muscle size (appendicular and site-specific) and composition (echo intensity) using DXA and ultrasound. Of the 32 older males (75.4 ± 7.9 years), 12 had low appendicular lean tissue. All DXA and ultrasound muscle characteristics were associated (r = 0.39 to 0.83, p < 0.05) with torque or power producing capabilities. Except for the knee flexors, no differences in correlation coefficients were observed between muscle thickness or regional lean tissue in relation to muscle strength. Neither DXA nor ultrasound muscle characteristics were associated with physical function. In older males, ultrasound-based muscle thickness and DXA lean tissue provided similar associations with strength. Novelty: Lean tissue and muscle thickness provide similar associations with strength. Muscle thickness can distinguish low and normal appendicular lean tissue in older adults.


Asunto(s)
Músculo Esquelético , Sarcopenia , Absorciometría de Fotón , Anciano , Envejecimiento , Composición Corporal , Fuerza de la Mano , Humanos , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/diagnóstico por imagen , Sarcopenia/diagnóstico por imagen
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