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Background: Firefighters have lower levels of physical activity while on call. It is critical to understand the impact of firefighters' physical activity on arterial stiffness. This study classified groups by physical activity level and combined peripheral vascular monitor measurement to explore the relationships between the level of physical activity and cardiovascular (CV) risk and physical fitness (PF) of firefighters, as well as the acute response to arterial stiffness (AS) following maximal aerobic exercise test (MAET) intervention. Methods: The International Physical Activity Questionnaire (IPAQ) was used to classify the participants into 3 groups: low, moderate, and high level of physical activity group, respectively. A total of 36 participants were recruited, 12 in each group. Participants were assessed for body composition, rest brachial-ankle pulse wave velocity (baPWV), handgrip strength (HGS), maximal oxygen uptake (VÌO2max), and MAET baPWV. Results: In the three groups, significant differences were observed in VÌO2max, HGS, relative fat mass (%FM), body mass index (BMI), muscle mass ratio (MMR), and Rest baPWV (p < 0.05). After maximal aerobic exercise, the MAET baPWV values decreased significantly in all groups (all p < 0.001). Rest baPWV was significantly correlated with firefighters' age, seniority, metabolic equivalents (METs), height and muscle mass (MM) (p < 0.05). Conclusions: Firefighters with high levels of physical activity had better body composition and physical fitness and lower Rest baPWV. In all three groups, baPWV was lower after the MAET than before it. Therefore, regardless of a firefighter's level of physical activity, high-intensity aerobic exercise may have a beneficial effect on arterial stiffness.
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Ejercicio Físico , Bomberos , Aptitud Física , Rigidez Vascular , Humanos , Rigidez Vascular/fisiología , Masculino , Adulto , Aptitud Física/fisiología , Ejercicio Físico/fisiología , Análisis de la Onda del Pulso , Composición Corporal/fisiología , Prueba de Esfuerzo/métodos , Fuerza de la Mano/fisiología , Consumo de Oxígeno/fisiología , Persona de Mediana Edad , Índice de Masa Corporal , Índice Tobillo Braquial , Femenino , Encuestas y CuestionariosRESUMEN
Determining an athlete's maximal peak power (MPP) is crucial in profiling endurance sports participants. While short (3 to 6 seconds) all-out efforts have been validated for MPP assessment, prior studies mainly involved non-endurance trained athletes. This study aimed to assess the intra- and inter-day reliability of a 6-second Wingate test for MPP determination in endurance athletes. Endurance-trained participants (22 males, 5 females) completed nine 6-second Wingate tests over four days (3 trials at baseline, 2 trials on each subsequent day). Analysis revealed no systematic differences in MPP (F(4.09, 106.3) = 1.88, p = 0.117) or time to peak power (χ2 (8) = 5.23, p = 0.732) across the trials. Reliability, assessed through the intraclass correlation coefficient (ICC) and standard error of measurement (SEM), was excellent across all trials (ICC = 0.95, SEM = 40.0W, SEM% = 3.7%). Absolute reliability improved when selecting the average or the best MPP values from each day (SEM% = 2.7% and 2.9%, respectively). Within-day reliability was consistently rated as excellent, with the best values on the 4th day of tests. No significant differences in MPP values occurred between the first and second 6-second Wingate tests on days 1 to 3, with both trials demonstrating similar reliability values (SEM%: 3.2% vs 2.8%, for the first and second trials, respectively). The test also demonstrated a good sensitivity to detect a meaningful change in MPP values. In conclusion, the 6-second Wingate test proves reliable for determining MPP in endurance-trained athletes. Two trials are recommended on the first day of testing, with a single MPP likely sufficient to determine the athlete's MPP on subsequent days.
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Atletas , Prueba de Esfuerzo , Resistencia Física , Humanos , Masculino , Femenino , Resistencia Física/fisiología , Reproducibilidad de los Resultados , Adulto , Prueba de Esfuerzo/métodos , Adulto JovenRESUMEN
Standard cardiopulmonary exercise testing (CPET) produces a rich dataset but its current analysis is often limited to a few derived variables such as maximal or peak oxygen uptake (VÌO2). We tested whether breath-by-breath CPET data could be used to determine sample entropy (SampEn) in 81 healthy children and adolescents (age 7-18 years old, equal sex distribution). To overcome challenges of the relatively small time-series CPET data size and its nonstationarity, we developed a Python algorithm for short-duration physiological signals. Comparing pre- and post-ventilatory threshold (VT1) CPET phases, we found: (1) SampEn decreased by 9.46% for VÌO2 and 5.01% for VÌCO2 (p < 0.05), in the younger, early-pubertal participants; and (2) HR SampEn fell substantially by 70.8% in the younger and 77.5% in the older participants (p < 0.001). Across all ages, females exhibited greater HR SampEn than males during both pre- and post VT1 CPET phases by 14.10% and 23.79%, respectively, p < 0.01. In females, late-pubertal had 17.6% lower HR SampEn compared to early-pubertal participants (p < 0.05). Breath-by-breath gas exchange and HR data from CPET are amenable to SampEn analysis that leads to novel insight into physiological responses to work intensity, and sex and maturational effects.
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Prueba de Esfuerzo , Frecuencia Cardíaca , Intercambio Gaseoso Pulmonar , Humanos , Niño , Masculino , Adolescente , Femenino , Prueba de Esfuerzo/métodos , Prueba de Esfuerzo/normas , Intercambio Gaseoso Pulmonar/fisiología , Frecuencia Cardíaca/fisiología , Consumo de Oxígeno/fisiología , EntropíaRESUMEN
Mitral regurgitation (MR) is associated with morphological and functional alterations of left atrium (LA) and ventricle (LV), possibly inducing LA-LV misalignment. We aimed to: (1) characterize angulation between LA and mitral annulus from conventional cine MRI data and feature-tracking (FT) contours, (2) assess their associations with functional capacity in MR patients, as assessed by oxygen consumption (peak-VO2) and minute ventilation to carbon dioxide production (VE/VCO2) slope, in comparison with MRI LA/LV strain indices. Thirty-two asymptomatic primary MR patients (56 [40; 66] years, 12 women) underwent cardiac MRI resulting in LA/LV conventional FT-derived strain indices. Then, end-diastolic angles were derived from FT LA contours: (1) α, centered on the LA centre of mass and defined by mitral valve extremities, (2) γ, centered on the mitral ring anterior/lateral side, and defined by LA centre and the other extremity of the mitral ring. Cardiopulmonary exercise testing with simultaneous echocardiography were also performed; peak-VO2 and VE/VCO2 slope were measured. While peak-VO2 and VE/VCO2 slope were not correlated to LA/LV strains, they were significantly associated with angles (α: r = 0.50, p = 0.003 and r = - 0.52, p = 0.003; γ: r = - 0.53, p = 0.002 and r = 0.52, p = 0.003; respectively), independently of age and gender (R2 ≥ 0.29, p ≤ 0.03). In primary MR, the new LA/mitral annulus angles, computed directly from standard-of-care MRI, are better correlated to exercise tolerance than conventional LA/LV strain.
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Ventrículos Cardíacos , Imagen por Resonancia Cinemagnética , Insuficiencia de la Válvula Mitral , Humanos , Femenino , Masculino , Persona de Mediana Edad , Imagen por Resonancia Cinemagnética/métodos , Insuficiencia de la Válvula Mitral/fisiopatología , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Anciano , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Adulto , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Prueba de Esfuerzo/métodos , Consumo de Oxígeno , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/fisiopatología , Ecocardiografía/métodosRESUMEN
Aortic valve replacement (AVR) leads to reverse cardiac remodeling in patients with aortic stenosis (AS). The aim of this secondary pooled analysis was to assess the degree and determinants of changes in myocardial perfusion post AVR, and its link with exercise capacity, in patients with severe AS. A total of 68 patients underwent same-day echocardiography and cardiac magnetic resonance imaging with adenosine stress pre and 6-12 months post-AVR. Of these, 50 had matched perfusion data available (age 67 ± 8 years, 86% male, aortic valve peak velocity 4.38 ± 0.63 m/s, aortic valve area index 0.45 ± 0.13cm2/m2). A subgroup of 34 patients underwent a symptom-limited cardiopulmonary exercise test (CPET) to assess maximal exercise capacity (peak VO2). Baseline and post-AVR parameters were compared and linear regression was used to determine associations between baseline variables and change in myocardial perfusion and exercise capacity. Following AVR, stress myocardial blood flow (MBF) increased from 1.56 ± 0.52 mL/min/g to 1.80 ± 0.62 mL/min/g (p < 0.001), with a corresponding 15% increase in myocardial perfusion reserve (MPR) (2.04 ± 0.57 to 2.34 ± 0.68; p = 0.004). Increasing severity of AS, presence of late gadolinium enhancement, lower baseline stress MBF and MPR were associated with a greater improvement in MPR post-AVR. On multivariable analysis low baseline MPR was independently associated with increased MPR post-AVR. There was no significant change in peak VO2 post-AVR, but a significant increase in exercise duration. Change in MPR was associated with change in peak VO2 post AVR (r = 0.346, p = 0.045). Those with the most impaired stress MBF and MPR at baseline demonstrate the greatest improvements in these parameters following AVR and the magnitude of change in MPR correlated with improvement in peak VO2, the gold standard measure of aerobic exercise capacity.
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Estenosis de la Válvula Aórtica , Válvula Aórtica , Prueba de Esfuerzo , Tolerancia al Ejercicio , Implantación de Prótesis de Válvulas Cardíacas , Humanos , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Masculino , Anciano , Femenino , Tolerancia al Ejercicio/fisiología , Prueba de Esfuerzo/métodos , Válvula Aórtica/cirugía , Válvula Aórtica/fisiopatología , Válvula Aórtica/diagnóstico por imagen , Persona de Mediana Edad , Circulación Coronaria , Índice de Severidad de la Enfermedad , Ecocardiografía , Imagen por Resonancia Magnética/métodosRESUMEN
OpenPose-based motion analysis (OpenPose-MA), utilizing deep learning methods, has emerged as a compelling technique for estimating human motion. It addresses the drawbacks associated with conventional three-dimensional motion analysis (3D-MA) and human visual detection-based motion analysis (Human-MA), including costly equipment, time-consuming analysis, and restricted experimental settings. This study aims to assess the precision of OpenPose-MA in comparison to Human-MA, using 3D-MA as the reference standard. The study involved a cohort of 21 young and healthy adults. OpenPose-MA employed the OpenPose algorithm, a deep learning-based open-source two-dimensional (2D) pose estimation method. Human-MA was conducted by a skilled physiotherapist. The knee valgus angle during a drop vertical jump task was computed by OpenPose-MA and Human-MA using the same frontal-plane video image, with 3D-MA serving as the reference standard. Various metrics were utilized to assess the reproducibility, accuracy and similarity of the knee valgus angle between the different methods, including the intraclass correlation coefficient (ICC) (1, 3), mean absolute error (MAE), coefficient of multiple correlation (CMC) for waveform pattern similarity, and Pearson's correlation coefficients (OpenPose-MA vs. 3D-MA, Human-MA vs. 3D-MA). Unpaired t-tests were conducted to compare MAEs and CMCs between OpenPose-MA and Human-MA. The ICCs (1,3) for OpenPose-MA, Human-MA, and 3D-MA demonstrated excellent reproducibility in the DVJ trial. No significant difference between OpenPose-MA and Human-MA was observed in terms of the MAEs (OpenPose: 2.4° [95%CI: 1.9-3.0°], Human: 3.2° [95%CI: 2.1-4.4°]) or CMCs (OpenPose: 0.83 [range: 0.99-0.53], Human: 0.87 [range: 0.24-0.98]) of knee valgus angles. The Pearson's correlation coefficients of OpenPose-MA and Human-MA relative to that of 3D-MA were 0.97 and 0.98, respectively. This study demonstrated that OpenPose-MA achieved satisfactory reproducibility, accuracy and exhibited waveform similarity comparable to 3D-MA, similar to Human-MA. Both OpenPose-MA and Human-MA showed a strong correlation with 3D-MA in terms of knee valgus angle excursion.
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Aprendizaje Profundo , Humanos , Reproducibilidad de los Resultados , Adulto Joven , Masculino , Femenino , Fenómenos Biomecánicos , Articulación de la Rodilla/fisiología , Grabación en Video , Adulto , Estudios de Tiempo y Movimiento , Algoritmos , Prueba de Esfuerzo/métodos , Ejercicio Pliométrico , Rango del Movimiento Articular/fisiología , Imagenología TridimensionalRESUMEN
Enhancing peak landing forces and ensuring faster stabilization in the lower limbs during jumping activities can significantly improve performance and decrease the risk of injury among basketball players. This study aimed to compare the effects of unilateral (uPJT) and bilateral plyometric jump training (bPJT) programs on various performance measures, including countermovement jump (CMJ), squat jump (SJ), and single-leg land and hold (SLLH) test outcomes, assessed using force plates. A randomized multi-arm study design was employed, comprising two experimental groups (n = 25; uPJT and n = 25; bPJT) and one control group (n = 25), conducted with youth male regional-level basketball players (16.3 ± 0.6 years old). Participants underwent assessment twice, both before and after an 8-week intervention training period. The uPJT program exclusively involved plyometric drills (e.g., vertical jump exercises; horizontal jump exercises) focusing on single-leg exercises, whereas the bPJT program utilized drills involving both legs simultaneously. The outcomes analyzed included CMJ peak landing force, CMJ peak power, SJ peak force, SJ maximum negative displacement, SLLH time to stabilization, and SLLH peak landing force. The control group exhibited significantly greater SLLH time to stabilization compared to both the uPJT (p < 0.001) and bPJT (p < 0.030) groups. Additionally, time to stabilization was also significantly higher in bPJT than in uPJT (p = 0.042). Comparisons between groups in regards SLLH peak landing force after intervention revealed that the value was significantly smaller in uPJT than in bPJT (p = 0.043) and control (p < 0.001). In the remaining outcomes of CMJ and SJ, both uPJT and bPJT showed significant improvement compared to the control group (p > 0.05), although there was no significant difference between them. In conclusion, our study suggests that utilizing uPJT is equally effective as bPJT in enhancing performance in bilateral jump tests. However, it significantly outperforms bPJT in improving time to stabilization and peak landing forces during single-leg land and hold test. uPJT could be advantageous not for maximizing performance but also for potentially decreasing injury risk by enhancing control and balance during single-leg actions, which are common in basketball.
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Rendimiento Atlético , Baloncesto , Ejercicio Pliométrico , Humanos , Baloncesto/fisiología , Masculino , Ejercicio Pliométrico/métodos , Adolescente , Rendimiento Atlético/fisiología , Extremidad Inferior/fisiología , Prueba de Esfuerzo/métodos , Fenómenos Biomecánicos , Fuerza Muscular/fisiología , Pierna/fisiología , Acondicionamiento Físico Humano/métodos , Acondicionamiento Físico Humano/fisiologíaRESUMEN
PURPOSE: Following acute myocardial infarction (AMI), patients with diabetes mellitus (DM) have a poorer prognosis than those without DM. This study aimed to investigate the benefit of cardiac rehabilitation on cardiorespiratory fitness in patients with AMI, examining whether this effect varied depending on DM and glycated hemoglobin (HbA1c) levels. METHODS: Data were collected from the medical records of 324 patients diagnosed with AMI who were subsequently referred to participate in a supervised exercise-based cardiac rehabilitation program. Cardiorespiratory fitness was assessed using cardiopulmonary exercise testing before and at 3 and 6 mo after the start of cardiac rehabilitation. Linear mixed models were used to evaluate changes in cardiorespiratory fitness between patients with and without DM during the follow-up period. RESULTS: In total, 106 patients (33%) had DM. Both patients with and without DM showed a significant improvement in cardiorespiratory fitness from baseline to the 6-mo follow-up. However, the improvement was significantly lower in patients with DM than in those without DM (1.9 ± 1.5 vs. 3.7 ± 3.2 mL/kg/min, P < .001). Among patients with DM, those with HbA1c levels < 7% showed a greater improvement in cardiorespiratory fitness than those with HbA1c ≥ 7% (2.7 ± 1.5 vs. 1.1 ± 1.8 mL/kg/min, P < .001) during the follow-up period. CONCLUSIONS: Improvements in cardiorespiratory fitness following cardiac rehabilitation were significantly lower in patients with AMI and DM. The response to cardiac rehabilitation in patients is influenced by HbA1c levels. These findings suggest potential implications for individualizing cardiac rehabilitation programming and ensuring optimal glycemic control in patients with AMI and DM.
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Rehabilitación Cardiaca , Capacidad Cardiovascular , Diabetes Mellitus , Hemoglobina Glucada , Infarto del Miocardio , Humanos , Masculino , Hemoglobina Glucada/análisis , Femenino , Infarto del Miocardio/rehabilitación , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/sangre , Capacidad Cardiovascular/fisiología , Persona de Mediana Edad , Rehabilitación Cardiaca/métodos , Diabetes Mellitus/fisiopatología , Diabetes Mellitus/sangre , Anciano , Terapia por Ejercicio/métodos , Prueba de Esfuerzo/métodos , Estudios RetrospectivosRESUMEN
PURPOSE: Given the difficulty to perform exercise training wearing a mask, we examined differences in functional capacity improvement between masking during the coronavirus disease 2019 (COVID-19) pandemic and non-masking prior to the pandemic for patients undergoing cardiac rehabilitation (CR). METHODS: Records of 660 patients who underwent and completed ≥ 18 sessions of CR in 2018 (n = 318, non-masking) and in 2022 (n = 342, masking) at an academic health system were analyzed. The primary outcome was post-CR change in functional capacity in metabolic equivalents (MET) measured by exercise stress test. Sessions of CR participation and changes in depression, anxiety, and quality of life scores were secondary outcomes. We used multivariable linear regression to adjust for differences in baseline CR outcome measures, demographics, American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR) risk, and comorbid conditions. RESULTS: Baseline age (64.6 ± 0.46 yr), sex (28% female), and racial distribution (85% white) were similar between the masking and non-masking groups. Non-masking patients were more likely to be classified in the AACVPR high risk category and had lower anxiety scores at baseline compared to masking patients. After CR, both groups had similar and significant improvements in depression, anxiety, and quality of life scores, but the improvement in functional capacity was lower in the masking group (-0.62 ± 0.12 MET, P < .001) compared to the non-masking group. Results remained significant after multivariable adjustment. CONCLUSIONS: Cardiac rehabilitation patients requiring masking during the COVID-19 pandemic had less improvement in functional capacity than patients who did not wear masks during CR prior to the pandemic. Interventions to mitigate the potential side effects of masking for CR patients may require further exploration.
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COVID-19 , Rehabilitación Cardiaca , Máscaras , Calidad de Vida , Humanos , COVID-19/epidemiología , Masculino , Femenino , Rehabilitación Cardiaca/métodos , Persona de Mediana Edad , SARS-CoV-2 , Anciano , Terapia por Ejercicio/métodos , Tolerancia al Ejercicio/fisiología , Ansiedad , Prueba de Esfuerzo/métodos , Depresión , Pandemias , Estudios RetrospectivosRESUMEN
Low-cost, portable devices capable of accurate physiological measurements are attractive tools for coaches, athletes, and practitioners. The purpose of this study was primarily to establish the validity and reliability of Movesense HR+ ECG measurements compared to the criterion three-lead ECG, and secondarily, to test the industry leader Garmin HRM. Twenty-one healthy adults participated in running and cycling incremental test protocols to exhaustion, both with rest before and after. Movesense HR+ demonstrated consistent and accurate R-peak detection, with an overall sensitivity of 99.7% and precision of 99.6% compared to the criterion; Garmin HRM sensitivity and precision were 84.7% and 87.7%, respectively. Bland-Altman analysis compared to the criterion indicated mean differences (SD) in RR' intervals of 0.23 (22.3) ms for Movesense HR+ at rest and 0.38 (18.7) ms during the incremental test. The mean difference for Garmin HRM-Pro at rest was -8.5 (111.5) ms and 27.7 (128.7) ms for the incremental test. The incremental test correlation was very strong (r = 0.98) between Movesense HR+ and criterion, and moderate (r = 0.66) for Garmin HRM-Pro. This study developed a robust peak detection algorithm and data collection protocol for Movesense HR+ and established its validity and reliability for ECG measurement.
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Electrocardiografía , Carrera , Humanos , Masculino , Adulto , Electrocardiografía/métodos , Carrera/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Reproducibilidad de los Resultados , Ciclismo/fisiología , Prueba de Esfuerzo/métodos , Adulto JovenRESUMEN
Elite athletes in speed roller skates perceive skating to be a more demanding exercise for the groin when compared to other cyclic disciplines, increasing their risk of injury. The objective of this study was to monitor the kinematic and electromyographic parameters of roller speed skaters, linearly, on a treadmill, and to compare different skating speeds, one at 20 km/h and one at 32 km/h, at a 1° inclination. The acquisition was carried out by placing an inertial sensor at the level of the first sacral vertebra, and eight surface electromyographic probes on both lower limbs. The kinematic and electromyographic analysis on the treadmill showed that a higher speed requires more muscle activation, in terms of maximum and average values and co-activation, as it not only increases the intrinsic muscle demand in the district, but also the athlete's ability to coordinate the skating technique. The present study allows us to indicate not only how individual muscle districts are activated during skating on a surface different from the road, but also how different speeds affect the overall district load distributions concerning effective force, which is essential for the physiotherapist and kinesiologist for preventive and conditional purposes, while also considering possible variations in the skating technique in linear advancement.
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Electromiografía , Patinación , Humanos , Electromiografía/métodos , Fenómenos Biomecánicos/fisiología , Patinación/fisiología , Masculino , Adulto , Prueba de Esfuerzo/métodos , Adulto Joven , Atletas , Músculo Esquelético/fisiología , FemeninoRESUMEN
The objective of this study was to assess the concurrent validity of the Kunwei force plate system in relation to variables during a counter-movement jump (CMJ) task, in comparison to the Kistler in-ground force plate system, which is considered the "gold standard". METHODS: In a single testing session, the Kunwei force plates were placed directly on top of the in-ground Kistler force plate. This allowed for the simultaneous collection of vertical ground reaction forces from 30 participants (male, age = 22.8 ± 2.8 years, body mass = 74.3 ± 12.3 kg, height 178.2 ± 4.6 cm) during CMJ tests. The consistency between force plate systems was assessed using ordinary least products regression (OLPR) with bootstrapped 95% confidence intervals and the Interclass Correlation Coefficient (ICC). RESULTS: There was no fixed or proportional bias in the CMJ variables measured between the force plate systems. The variables exhibited a strong correlation across the force plates during the CMJ task (ICC > 0.950, p < 0.01). CONCLUSION: The findings of this study indicate that there was no statistical difference between the Kunwei and Kistler force plate systems when evaluating common CMJ strategy and outcome variables, which are considered the gold standard. Hence, the Kunwei force plate can be regarded as a reliable substitute for the established industry benchmark in evaluating the force-time characteristics of the CMJ. Researchers, athletes, and coaches have the option to utilize this affordable and portable choice as a substitute for the more expensive laboratory-based force plate system. This alternative allows for the precise measurement of CMJ performance and force-time variables.
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Movimiento , Humanos , Masculino , Movimiento/fisiología , Adulto Joven , Adulto , Fenómenos Biomecánicos/fisiología , Prueba de Esfuerzo/métodos , Rendimiento Atlético/fisiologíaRESUMEN
People with end-stage kidney disease (ESKD) often exhibit impaired cardiac structure and function, which may contribute to poor exercise capacity. This study used multimodal exercise testing to investigate the central and peripheral mechanisms of exercise limitation in adults with ESKD, also comparing in-centre hemodialysis (ICHD) to home hemodialysis (HHD). Seventeen adults (55.5 ± 14.5 years; n = 14 male; n = 12 HHD) participated. Resting cardiac examinations, followed by submaximal cycling cardiopulmonary exercise testing (CPET) and functional exercise testing, revealed cardiac structural abnormalities (increased left ventricular mass) and cardiac injury. Aerobic fitness in adults with ESKD was low, with pulmonary oxygen uptake (VÌO2) at the gas exchange threshold (GET) occuring at 39 ± 8% predicted VÌO2peak. O2 pulse, an estimate of stroke volume (SV), was higher in HHD at rest (p = 0.05, ES = 0.58) and during unloaded cycling (p = 0.05, ES = 0.58) compared to ICHD. However, thoracic bioreactance derived SV at the GET was significantly higher in adults receiving ICHD versus HHD (p = 0.01, ES = 0.74). In adults with ESKD, cardiac output was positively associated with VÌO2 at the GET (r = 0.61, p = 0.04). This study highlights prevalent exercise dysfunction in adults with ESKD undergoing dialysis, with potential distinct differences between in-centre and home hemodialysis, mechanistically linked to underlying cardiac abnormalities.
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Prueba de Esfuerzo , Tolerancia al Ejercicio , Fallo Renal Crónico , Diálisis Renal , Humanos , Masculino , Persona de Mediana Edad , Femenino , Fallo Renal Crónico/fisiopatología , Fallo Renal Crónico/terapia , Proyectos Piloto , Anciano , Adulto , Prueba de Esfuerzo/métodos , Diálisis Renal/efectos adversos , Tolerancia al Ejercicio/fisiología , Consumo de OxígenoRESUMEN
A cardiopulmonary exercise test (CPET) is a test assessing an individual's physiological response during exercise. Results may be affected by body composition, which is best evaluated through imaging techniques like magnetic resonance imaging (MRI). The aim of this study was to assess relationships between body composition and indices obtained from CPET. A total of 234 participants (112 female), all aged 50 years, underwent CPETs and whole-body MRI scans (> 1 million voxels). Voxel-wise statistical analysis of tissue volume and fat content was carried out with a method called Imiomics and related to the CPET indices peak oxygen consumption (VÌO2peak), VÌO2peak scaled by body weight (VÌO2kg) and by total lean mass (VÌO2lean), ventilatory efficiency (VÌE/VÌCO2-slope), work efficiency (ΔVÌO2/ΔWR) and peak exercise respiratory exchange ratio (RERpeak). VÌO2peak showed the highest positive correlation with volume of skeletal muscle. VÌO2kg negatively correlated with tissue volume in subcutaneous fat, particularly gluteal fat. RERpeak negatively correlated with tissue volume in skeletal muscle, subcutaneous fat, visceral fat and liver. Some associations differed between sexes: in females ΔVÌO2/ΔWR correlated positively with tissue volume of subcutaneous fat and VÌE/VÌCO2-slope with tissue volume of visceral fat, and, in males, VÌO2peak correlated positively to lung volume. In conclusion, voxel-based Imiomics provided detailed insights into how CPET indices were related to the tissue volume and fat content of different body structures.
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Composición Corporal , Prueba de Esfuerzo , Imagen por Resonancia Magnética , Consumo de Oxígeno , Humanos , Femenino , Masculino , Persona de Mediana Edad , Composición Corporal/fisiología , Prueba de Esfuerzo/métodos , Imagen por Resonancia Magnética/métodos , Consumo de Oxígeno/fisiología , Músculo Esquelético/fisiología , Músculo Esquelético/diagnóstico por imagen , Ejercicio Físico/fisiologíaRESUMEN
Ground reaction force (GRF) data is often collected for the biomechanical analysis of running, due to the performance and injury risk insights that GRF analysis can provide. Traditional methods typically limit GRF collection to controlled lab environments, recent studies have looked to combine the ease of use of wearable sensors with the statistical power of machine learning to estimate continuous GRF data outside of these restrictions. Before such systems can be deployed with confidence outside of the lab they must be shown to be a valid and accurate tool for a wide range of users. The aim of this study was to evaluate how accurately a consumer-priced sensor system could estimate GRFs whilst a heterogeneous group of runners completed a treadmill protocol with three different personalised running speeds and three gradients. Fifty runners (25 female, 25 male) wearing pressure insoles made up of 16 resistive sensors and an inertial measurement unit ran at various speeds and gradients on an instrumented treadmill. A long short term memory (LSTM) neural network was trained to estimate both vertical ( G R F v ) and anteroposterior ( G R F a p ) force traces using leave one subject out validation. The average relative root mean squared error (rRMSE) was 3.2% and 3.1%, respectively. The mean ( G R F v ) rRMSE across the evaluated participants ranged from 0.8% to 8.8% and from 1.3% to 17.3% in the ( G R F a p ) estimation. The findings from this study suggest that current consumer-priced sensors could be used to accurately estimate two-dimensional GRFs for a wide range of runners at a variety of running intensities. The estimated kinetics could be used to provide runners with individualised feedback as well as form the basis of data collection for running injury risk factor studies on a much larger scale than is currently possible with lab based methods.
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Aprendizaje Profundo , Carrera , Dispositivos Electrónicos Vestibles , Humanos , Carrera/fisiología , Masculino , Femenino , Adulto , Fenómenos Biomecánicos/fisiología , Prueba de Esfuerzo/instrumentación , Prueba de Esfuerzo/métodos , Adulto JovenRESUMEN
BACKGROUND: Invasive cardiopulmonary exercise testing (iCPET) combines traditional cardiopulmonary exercise testing with invasive hemodynamic measurements to assess exercise intolerance, which can be caused by preload insufficiency (PI), characterized by low ventricular filling pressures and reduced cardiac output during exertion. We hypothesize that plasma catecholamine levels at rest and during exercise correlate with hemodynamic parameters in PI. METHODS: We included adult patients who underwent iCPET for exercise intolerance and had plasma catecholamines measured at rest and peak exercise. RESULTS: Among 84 patients, PI was identified in 57 (67.8 %). Compared to patients without PI, those with PI were younger [median (IQR) 37 (28, 46) vs 47 (39,55) years, p = 0.005] and had lower workload at peak exercise [81 (66, 96) vs 95 (83.5, 110.50) Watts, p = 0.006]. Patients with PI had higher heart rates at rest and peak exercise [87 (78, 97) vs 79 (74, 87) bpm, p = 0.04; and 167 (154, 183) vs 156 (136, 168) bpm, p = 0.01, respectively]. In all patients, epinephrine and norepinephrine at peak exercise directly correlated with peak workload (r:0.41, p < 0.001 and r:0.47, p < 0.001, respectively). Resting epinephrine was higher in patients with PI [136 (60, 210) vs 77 (41, 110) pg/mL, p = 0.02]. There was no significant difference in the change in catecholamines from rest to peak exercise between patients with or without PI. CONCLUSION: PI patients exhibited elevated heart rate and epinephrine at rest, indicating increased sympathetic activity. We did not find strong associations between catecholamines and cardiac filling pressures, suggesting that catecholamine levels are predominantly influenced by peak workload.
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Catecolaminas , Prueba de Esfuerzo , Tolerancia al Ejercicio , Humanos , Prueba de Esfuerzo/métodos , Persona de Mediana Edad , Masculino , Tolerancia al Ejercicio/fisiología , Femenino , Catecolaminas/sangre , Adulto , Norepinefrina/sangre , Hemodinámica/fisiología , Frecuencia Cardíaca/fisiología , Epinefrina/sangre , Ejercicio Físico/fisiología , Gasto Cardíaco/fisiologíaRESUMEN
Lactate analysis plays an important role in sports science and training decisions for optimising performance, endurance, and overall success in sports. Two parameters are widely used for these goals: aerobic (AeT) and anaerobic (AnT) thresholds. However, determining AeT proves more challenging than AnT threshold due to both physiological intricacies and practical considerations. Thus, the aim of this study was to determine AeT and AnT thresholds using machine learning modelling (ML) and to compare ML-obtained results with the parameters' values determined using conventional methods. ML seems to be highly useful due to its ability to handle complex, personalised data, identify nonlinear relationships, and provide accurate predictions. The 183 results of CardioPulmonary Exercise Test (CPET) accompanied by lactate and heart ratio analyses from amateur athletes were enrolled to the study and ML models using the following algorithms: Random Forest, XGBoost (Extreme Gradient Boosting), and LightGBM (Light Gradient Boosting Machine) and metrics: R2, mean absolute error (MAE), mean squared error (MSE) and root mean square error (RMSE). The regressors used belong to the group of ensemble learning algorithms that combine the predictions of multiple base models to improve overall performance and counteract overfitting to training data. Based on evaluation metrics, the following models give the best predictions: for AeT: Random Forest has an R2 value of 0.645, MAE of 4.630, MSE of 44.450, RMSE of 6.667; and for AnT: LightGBM has an R2 of 0.803, the highest among the models, MAE of 3.439, the lowest among the models, MSE of 20.953, and RMSE of 4.577. Outlined research experiments, a comprehensive review of existing literature in the field, and obtained results suggest that ML models can be trained to make personalised predictions based on an individual athlete's unique physiological response to exercise. Athletes exhibit significant variation in their AeT and AT, and ML can capture these individual differences, allowing for tailored training recommendations and performance optimization.
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Umbral Anaerobio , Atletas , Aprendizaje Automático , Humanos , Umbral Anaerobio/fisiología , Masculino , Adulto , Prueba de Esfuerzo/métodos , Femenino , Adulto Joven , Ácido Láctico/sangre , AlgoritmosRESUMEN
Oxygen uptake (VËO2) is an essential metric for evaluating cardiopulmonary health and athletic performance, which can barely be directly measured. Heart rate (HR) is a prominent physiological indicator correlated with VËO2 and is often used for indirect VËO2 prediction. This study investigates the impact of HR placement on VËO2 prediction accuracy by analyzing HR data combined with the respiratory rate (RESP) and minute ventilation (VËE) from three anatomical locations: the chest; arm; and wrist. Twenty-eight healthy adults participated in incremental and constant workload cycling tests at various intensities. Data on VËO2, RESP, VËE, and HR were collected and used to develop a neural network model for VËO2 prediction. The influence of HR position on prediction accuracy was assessed via Bland-Altman plots, and model performance was evaluated by mean absolute error (MAE), coefficient of determination (R2), and mean absolute percentage error (MAPE). Our findings indicate that HR combined with RESP and VËE (VËO2HR+RESP+VËE) produces the most accurate VËO2 predictions (MAE: 165 mL/min, R2: 0.87, MAPE: 15.91%). Notably, as exercise intensity increases, the accuracy of VËO2 prediction decreases, particularly within high-intensity exercise. The substitution of HR with different anatomical sites significantly impacts VËO2 prediction accuracy, with wrist placement showing a more profound effect compared to arm placement. In conclusion, this study underscores the importance of considering HR placement in VËO2 prediction models, with RESP and VËE serving as effective compensatory factors. These findings contribute to refining indirect VËO2 estimation methods, enhancing their predictive capabilities across different exercise intensities and anatomical placements.
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Frecuencia Cardíaca , Consumo de Oxígeno , Frecuencia Respiratoria , Humanos , Frecuencia Cardíaca/fisiología , Masculino , Frecuencia Respiratoria/fisiología , Adulto , Femenino , Consumo de Oxígeno/fisiología , Adulto Joven , Oxígeno/metabolismo , Prueba de Esfuerzo/métodos , Ejercicio Físico/fisiologíaRESUMEN
The purpose of this study was to examine the test-retest reliability of strength-endurance protocols using isometric mid-thigh pull (IMTP). Twenty-eight participants (23.2 ± 4.9 years) completed two protocols across four testing sessions. Protocol one consisted of 10 maximal IMTP tests lasting 5 seconds each with 10 seconds rest between. Protocol two consisted of a prolonged 60 second maximal IMTP. Data from protocol 1 was analysed in two ways; (a) use of the highest peak value from the first three IMTP efforts, and the lowest peak value from the final three IMTP efforts, and (b) use of the mean peak force from the first three IMTP efforts and mean peak force from the final three IMTP efforts. Data from protocol two used the highest and lowest peak values in the first- and final-15 seconds. Analyses revealed excellent reliability for peak force across all four testing sessions (ICC = 0.94), as well as good test-retest reliability for strength-endurance for protocol 1 (a; ICC = 0.81, b; ICC = 0.79). Test-retest reliability for protocol 2 was poor (ICC = 0.305). Bland-Altman bias values were smaller for protocol 1(a = -8.8 Nm, b = 21.7 Nm) compared to protocol 2 = (119.3 Nm). Our data suggest that 10 maximal IMTP tests performed as described herein is a reliable method for exercise professionals to assess both peak force and strength-endurance in a single, time-efficient protocol.
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Contracción Isométrica , Fuerza Muscular , Resistencia Física , Muslo , Humanos , Reproducibilidad de los Resultados , Masculino , Contracción Isométrica/fisiología , Fuerza Muscular/fisiología , Resistencia Física/fisiología , Femenino , Adulto , Adulto Joven , Muslo/fisiología , Prueba de Esfuerzo/métodos , Prueba de Esfuerzo/normas , Músculo Esquelético/fisiologíaRESUMEN
There are over 5.3 million Americans who face acquired brain injury (ABI)-related disability as well as almost 800,000 who suffer from stroke each year. To improve mobility and quality of life, rehabilitation professionals often focus on walking recovery soon after hospital discharge for ABI. Reduced propulsion capacity (force output of the lower limbs to counteract ground reaction forces) negatively impacts walking ability and complicates recovery during rehabilitation for brain injured people. We describe a method, using backward-directed resistance (BDR) in a robotic-based treadmill device, to allow measurement of maximum walking propulsion force (MWPF) that is not otherwise possible during overground walking assessment. Our objective was to test the construct validity of a maximum walking propulsion force (MWPF) measure that reflects a person's propulsive strength against applied BDR, while walking on a robotic treadmill-based device for participants with acquired brain injury (ABI). Our study enrolled 14 participants with ABI at an in inpatient rehabilitation in Galveston, TX from 8/1/21 - 4/31/22. The range of weight-adjusted MWPF was 2.6-27.1% body weight (%BW), mean 16.5 ± 8.4%BW, reflecting a wide range of propulsive force capability. The strongest correlation with overground tests was between the 6-minute walk test (6-MWT) distance and the MWPF values (r = 0.83, p < 0.001) with moderate correlations between the 10-meter walk tests at comfortable (CWS) and fast speeds (FWS). The Five Times Sit-to-Stand (used as a standard clinical measure of functional lower extremity strength) and MWPF tests were poorly correlated (r = 0.26, p = 0.4). Forward model selection included 6-MWT distance, age, and overground CWS as significant partial predictors of MWPF. We conclude that this novel MWPF measure is a valid representation of maximum propulsive force effort during walking for people post-ABI. Additional research could help determine the impact of interventions designed to increase propulsive force generation during rehabilitation training to improve overground walking performance.