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Introducción: Sólo Oga et al. (AJRCCM 2003) relacionaron supervivencia y capacidad aeróbica en pacientes EPOC, pero en hombres y seguimiento a 5 años. Objetivos: Evaluar la supervivencia de una cohorte de pacientes EPOC grave según el consumo de oxígeno pico (VO2p) ajustado al peso. Material y Métodos: Se evaluó la supervivencia a largo plazo desde el diagnóstico de pacientes con EPOC (GOLD). Se midió el VO2p ajustado por peso en prueba cicloergo- métrica máxima (gases espirados). Se usaron técnicas estadísticas convencionales y análisis de supervivencia de LogRank (Mantel-Cox). Resultados: 70 pacientes (27% femenino); edad 68 años (RIQ 63-73); %FEV1 postBD: 39,95±2,09; VO2p: 9,25 ± 3,17 ml/kg/min. GOLD D/B/A 84,3/14,2/1,5%; GOLD II/III/IV: 15,7/61,4/22,9%. A 14 años de seguimiento, 75% había fallecido. Supervivencia: primer cuartilo de VO2p (ml/kg/min) fue 38,5 meses (RIQ 18,25-58,5) y para el cuarto cuartilo 68 meses (RIQ 48-93). A 103 meses, la diferencia en supervivencia fue: primer cuartilo vs. cuarto cuartilo de VO2p (p<0,01) y segundo vs. cuarto cuartilo (p<0,03); a 145 meses entre segundo vs. cuarto cuartilo (p=0,049). En el análisis multivariado, el VO2p alto es un factor protector sobre la mortalidad. En cambio, otras variables independientes como sexo masculino, edad >70, grado de obstrucción bronquial severo y fenotipo exacerbador frecuente se asociaron a mortalidad. Conclusión: A largo plazo, en una cohorte de pacientes hombres y mujeres EPOC grave, en análisis multivariado, el VO2p alto es factor protector sobre la mortalidad. En cambio, otras variables independientes como sexo masculino, edad >70, grado de obstrucción bronquial severo y exacerbador frecuente se asociaron a mortalidad.

Introduction: Only Oga et al. (AJRCCM 2003) related survival and aerobic capacity, but only in chronic obstructive pulmonary disease (COPD) men with 5 years of follow-up. Objective: To determine survival in a cohort of patients with severe COPD due to aerobic capacity (VO2max) adjusted by weight. Methods: Survival of COPD patients was evaluated to long-term (GOLD definition). Patients performed maximal exercise test in cicloergometry (expired gases) evaluating (VO2max). Conventional statistics and Log-Rank survival analysis (Mantel-Cox) were used. Results: We included 70 patients (27% female) followed up 60.77 months (RIQ 29- 87.85); age 68 years (RIQ 63-73); %FEV1 postBD: 39.95±2.09; VO2p: 9.25± 3.17 ml/kg/ min. GOLD D/B/A 84.3/14.2/1.5%; GOLD II/III/IV: 15.7/61.4/22.9%. After 14 years of follow-up, 75% of patients died. Survival: VO2p (ml/kg/min) first quartil was 38.5 months (RIQ 18,25-58,5); second quartil 66 months (RIQ 35-84.5); third quartil 70 months (RIQ 15-96) and fourth quartil 68 months (RIQ 48-93). After 103 months of follow-up, survival was compared: 1st vs 4rd quartil of VO2p (p<0.01) and 2nd vs. 4rd quartil (p<0.03); comparing at 145 months: 2nd vs. 4rd quartil (p=0.049). In a multivariate analysis, high VO2p is a protective factor on mortality, nevertheless other independent variables as male gender, age >70, severe airway obstruction and frequent exacerbators were associated to mortality. Conclusion: At long term of follow-up, a cohort of severe COPD patients (males and fe- males), in multivariate analysis, high VO2p is a protective factor of mortality, nevertheless other independent variables as male gender, age >70, severe airway obstruction and frequent exacerbators were associated to mortality.

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In recent years, absorbers related to metamaterials have been heavily investigated. In particular, VO2 materials have received focused attention, and a large number of researchers have aimed at multilayer structures. This paper presents a new concept of a three-layer simple structure with VO2 as the base, silicon dioxide as the dielectric layer, and graphene as the top layer. When VO2 is in the insulated state, the absorber is in the closed state, Δf = 1.18 THz (absorption greater than 0.9); when VO2 is in the metallic state, the absorber is open, Δf = 4.4 THz (absorption greater than 0.9), with ultra-broadband absorption. As a result of the absorption mode conversion, a phenomenon occurs with this absorber, with total transmission and total reflection occurring at 2.4 THz (A = 99.45% or 0.29%) and 6.5 THz (A = 90% or 0.24%) for different modes. Due to this absorption property, the absorber is able to achieve full-transmission and full-absorption transitions at specific frequencies. The device has great potential for applications in terahertz absorption, terahertz switching, and terahertz modulation.

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With the development of technology, multifunctional multiband emitters have been paid much attention due to their wide range of applications, such as LIDAR detection, spectroscopic sensing, and infrared thermal management. However, the development of such emitters is impeded by incompatible structural requirements of different electromagnetic wavebands. Here, we demonstrate coupled modulation between near-infrared (NIR) laser-wavelength and long-wavelength-infrared by constructing a multifunctional emitter (MFE) with a structure of Al/HfO2/VO2, utilizing the phase transition of VO2. The MFE displays excellent thermal modulation capability within the 8-14 µm range, achieving a thermal insulation effect (ε8-14 µm = 0.18) at low temperatures, and heat dissipation effect (ε8-14 µm = 0.64) at high temperatures. The MFE's radiation power regulation capability is 145.06 W m-2 between a temperature of 0 to 60 °C. Moreover, the MFE possesses a large reflectivity modulation value of 0.78 at NIR laser-wavelength (1.06 µm) with a short phase transition time of 1003 ms under 3 W cm-2 laser irradiation. This study provides a guideline for the coordinated control of electromagnetic waves and intelligent collaborative thermal management through simple structural design, thus, having broad implications in energy saving and thermal information processing.

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People with HIV (PWH) are at increased risk for metabolic disorders affecting body mass index (BMI), chronic symptoms, and impaired physical function and capacity. Although physical activity improves health and well-being, PWH often do not meet activity recommendations necessary to achieve these benefits. Despite the known impact of symptoms, physical activity, and physical function on health, little is known about the relationships and interactions between these variables and BMI and maximum oxygen consumption during exercise (VO2 max) in a multinational population of PWH. We examined the relationship of BMI with PROMIS-29 measures, physical activity, strength, flexibility, and VO2 max in a diverse sample of PWH. Additionally, we examined the relationship of VO2 max with PROMIS-29 measures. Data from 810 PWH who participated in a cross-sectional study conducted by the International Nursing Network for HIV Research (Study VII) were analyzed. Participants were recruited from 8 sites across the United States, Thailand, and South Africa. BMI was calculated from collected height and weight data. Physical function and symptoms were assessed using the PROMIS-29 measure. Physical activity was assessed using the 7-day Physical Activity Recall. VO2 max was calculated using sex at birth, age, BMI and the 6-minute Walk Test. Data were analyzed using descriptive, correlational, and regression statistical analyses. Participants had an average age of 49.1 (± 11.1) years, 44% were female, and the average BMI of the sample group was 27 kg/m2 (± 6.7). Increased BMI was associated with decreased 6-minute Walk Test (ß=-2.18, p < 0.001), flexibility (ß=-0.279, p < 0.001), and VO2 max (ß=-0.598, p < 0.001), even after controlling for covariates (age, sex at birth, country, years living with HIV, and antiretroviral therapy status). BMI was not associated with self-reported physical activity. Increased VO2 max was associated with increased physical function (ß = 0.069, p < 0.001), and decreased pain (ß=-0.047, p < 0.006), even after controlling for covariates (country, years living with HIV, and antiretroviral therapy status). Future research should explore development of effective and sustainable symptom self-management interventions in PWH accounting for the potential impact of BMI and VO2 max.

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Background: This meta-analysis aimed to evaluate the impact of aerobic exercise on Peak VO2 (Oxygen Consumption) in postoperative patients with congenital heart disease (CHD). Besides this, we also tried to discover whether the improvement was influenced by patient ages, modes of supervision, types of exercise, the total dose of exercise, intervention periods, and types of CHD. Methods: Following the Population Intervention Comparison Outcome Study Design (PICOS) principle, a comprehensive search of the PubMed, Web of Science, Embase and Cochrane Library databases was conducted for randomized controlled trials (RCTs) evaluating the intervention effects of aerobic exercise on cardiopulmonary function in postoperative CHD patients until December 2023. This meta-analysis and publication bias tests were conducted using Stata 17.0, and the mean differences (MDs) with 95% confidence intervals (CIs) were used as effect sizes in statistics. Results: A total of 15 RCTs (762 cases) were included in this meta-analysis, with 407 cases in the experimental group and 355 cases in the control group. Meta-analysis showed that aerobic exercise had a positive effect on Peak VO2 in postoperative CHD patients (MD = 2.14, 95% CI (1.34, 2.94), p < 0.00001, I2 = 36%). The analysis of subgroups showed that intervention effects of aerobic exercise were superior to the control group when patients were > 18 years old (MD = 2.53, p < 0.00001), ≤ 18 years old (MD = 1.63, p = 0.01), under supervision (MD = 2.23, p < 0.00001), unsupervised (MD = 2.06, p < 0.00400), performing aerobic exercise (MD = 1.87, p = 0.0003), performing aerobic exercise combined with resistance training (MD = 2.57, p < 0.00010), with a total dose of exercise ≥ 1440 minutes (MD = 2.45, p < 0.00010), with the intervention period of 10-12 weeks (MD = 2.31, p < 0.00001), with that > 12 weeks (MD = 1.97, p = 0.00300), or with mixed types of CHD (MD = 2.34, p < 0.00001). Conclusions: This meta-analysis did not deduct points for limitations, inconsistency, indirectness, imprecision, or publication bias, so the quality of evidence was graded as high. Aerobic exercise has a significantly positive impact on improving Peak VO2 in postoperative CHD patients. Moreover, it was found that for patients aged 18 and above, supervised aerobic exercise combined with resistance training, implemented for 10-12 weeks with a total dose of exercise ≥ 1440 minutes, had a better intervention effect on Peak VO2. This finding provided evidence-based medicine for the exercise rehabilitation of postoperative CHD patients, and explored the optimal exercise prescription for clinical practice as well. Clinical Trial registration: Registered on INPLASY No.202440016 (https://inplasy.com).

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Polarized Raman spectroscopy was used to analyze aqueous solutions of sodium orthophosphate and orthovanadate over a wide concentration range (0.00891-0.702 mol/L) at 23 °C. The isotropic scattering profiles were obtained by measuring polarized Raman scattering spectra. Furthermore, R-normalized spectra were calculated and presented. The tetrahedral ions, VO43-(aq) and PO43-(aq), demand four Raman active bands which have been subsequently characterized and assigned. For the PO43-(aq) ion, the deformation modes ν2(e) and ν4(f2) appear at 415 and 557 cm-1, and these modes are depolarized. In the P-O stretching region, the strongest Raman band appears at 936.5 cm-1, which is totally polarized with a depolarization ratio (ρ-value) of 0.002. The broad and depolarized mode at 1010 cm-1 constitutes the antisymmetric stretching band ν3(f2). The Raman spectrum of VO43- shows two depolarized deformation modes ν2(e) and ν4(f2) at 327 and 345.6 cm-1, which are severely overlapped. These bands are very weak. The strongest band in the Raman spectrum of VO43-(aq) is the symmetric stretching mode ν1(a1) at 820.2 cm-1 which is totally polarized with a ρ-value at 0.004. The depolarized antisymmetric stretching mode ν3(f2) appeared at 785 cm-1 as a broad and weak band. Both anions are strongly hydrated and showed extensive hydrolysis in an aqueous solution. Orthovanadate is a much stronger base than orthophosphate in aqueous solution. Therefore, a large amount of NaOH was used to suppress the hydrolysis of VO43-(aq) sufficiently, so, it was possible to characterize the VO43- modes. Quantitative Raman spectroscopy was applied to follow the hydrolysis of PO43- over a wide concentration range from 0.00891 to 0.592 mol/L. The hydrolysis data allowed the calculation of the pKa3 value for H3PO4 to be 12.330 ± 0.02 (25 °C). The hydrolysis of the VO43- ion is ∼21 times larger than that of the PO43-. The pKa3 value for H3VO4 is estimated to be 13.65 ± 0.1 (25 °C).

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Advancing cathode materials is crucial for the broader application of aqueous zinc-ion batteries (ZIBs) in energy storage systems. This study presents amorphous H/VO4 (HVO), a novel cathode material engineered by substituting H+ for Mg2+ in Mg2VO4 (MgVO), designed to enhance performance of ZIBs. Initial exploration of MgVO through ab initio molecular dynamics (AIMD) simulations and density functional theory (DFT) calculations revealed a favorable Mg2+ and Zn2+ exchange mechanism. This mechanism notably reduces electrostatic interactions and facilitates ion diffusion within the host lattice. Building upon these findings, in this work, theoretical calculations analysis indicated that amorphous HVO offers a higher diffusion coefficient for Zn2+ ions and fewer electrostatic interactions compared to its crystalline MgVO precursor. Subsequent empirical validation is achieved by synthesizing amorphous HVO using a rapid ion-exchange process, effectively replacing Mg2+ with H+ ions. The synthesized amorphous HVO demonstrated 100% capacity retention after 18000 cycles at a current density of 2 A g-1 and exhibited exceptional rate performance. These findings underscore the significant potential of HVO cathodes to enhance the durability and efficiency of aqueous ZIBs, positioning them as promising candidates for future energy storage technologies.

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Vanadium dioxide (VO2) materials exhibit significant theoretical specific capacity, which is ascribed to multi-electron transfer reactions and unique tunneled structures. However, the low electronic conductivity and sluggish reaction kinetics of VO2 have impeded its further development. Hence, in this study, we employed a synergistic strategy of defect engineering and compositing with a calabash carbon matrix to reduce Zn2+ diffusion barriers and accelerate electron transfer. The VO2 cathode provided a high specific capacity at a low rate of 303 mA h g-1 at 0.1 A g-1 after 191 cycles, along with good rate performance (168 mA h g-1 at 10 A g-1) and satisfactory long-term stability (170 mA h g-1 at 1 A g-1 after 1100 cycles). The exhaustive structural analyses indicated that oxygen vacancies accelerated the Zn2+ diffusion rate, while a uniform calabash-like hollow carbon matrix improved electronic conductivity during cycling. Moreover, ex-situ measurements demonstrated that during discharge, the composite cathode transformed to layered Zn3+x(OH)2V2O7·2H2O, which then facilitated the subsequent intercalation of Zn2+. This cooperative strategy advances the practical application of aqueous zinc ion batteries by leveraging vanadium-based electrodes.

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In the extreme space environment, spacecraft endure dramatic temperature variations that can impair their functionality. A VO2-based smart radiator device (SRD) offers an effective solution by adaptively adjusting its radiative properties. However, current research on VO2-based thermochromic films mainly focuses on optimizing the emissivity tunability (Δε) of single-cycle sandwich structures. Although multi-cycle structures have shown increased Δε compared to single-cycle sandwich structures, there have been few systematic studies to find the optimal cycle structure. This paper theoretically discusses the influence of material properties and cyclic structure on SRD performance using Finite-Difference Time-Domain (FDTD) software, which is a rigorous and powerful tool for modeling nano-scale optical devices. An optimal structural model with maximum emissivity tunability is proposed. The BaF2 obtained through optimization is used as the dielectric material to further optimize the cyclic resonator. The results indicate that the tunability of emissivity can reach as high as 0.7917 when the BaF2/VO2 structure is arranged in three periods. Furthermore, to ensure a longer lifespan for SRD under harsh space conditions, the effects of HfO2 and TiO2 protective layers on the optical performance of composite films are investigated. The results show that when TiO2 is used as the protective layer with a thickness of 0.1 µm, the maximum emissivity tunability reaches 0.7932. Finally, electric field analysis is conducted to prove that the physical mechanism of the smart radiator device is the combination of stacked Fabry-Perot resonance and multiple solar reflections. This work not only validates the effectiveness of the proposed structure in enhancing spacecraft thermal control performance but also provides theoretical guidance for the design and optimization of SRDs for space applications.

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The purpose of this study was to investigate the potential ergogenic effects of an oral lactate supplement. For this double-blind, randomized, placebo-controlled crossover design, fifteen recreational exercisers (nine males, six females) ingested a placebo or a commercially available lactate supplement prior to cycle ergometer exercise. Primary outcomes included peak oxygen uptake (VO2peak; via indirect calorimetry), VO2 at the ventilatory threshold, and work rate at the lactate threshold (arterialized venous blood from a heated hand) determined during incremental exercise to fatigue, and power output during a 20-min cycling time trial. Compared with placebo, the oral lactate supplement (19 ± 1 mg/kg body mass) did not influence VO2peak (placebo: 44.3 ± 7.8 vs. oral lactate: 44.3 ± 7.1 mL/kg/min (mean ± SD); p = 0.87), VO2 at the ventilatory threshold (placebo: 1.63 ± 0.25 vs. oral lactate: 1.65 ± 0.23 L/min; p = 0.82), or work rate at the lactate threshold (placebo: 179 ± 69 vs. oral lactate: 179 ± 59 W; p = 0.41). Throughout the 20-min time trial, the work rate was slightly greater (4%) with oral lactate (204 ± 41 W) compared with placebo (197 ± 41 W; main effect of treatment p = 0.02). Collectively, these data suggest that this commercially available lactate supplement did not acutely influence the physiological responses to incremental cycle ergometer exercise but elicited a modest ergogenic effect during the short-duration time trial.

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BACKGROUND: This study was designed to evaluate the effect of using maximal cadence criteria cut points established during overground and treadmill walking, on intensity outputs measured during community ambulation. The second aim was to establish the relationship between cardiovascular fitness (predicted VO2 max capacity) and community ambulation intensity performance, in typically developing individuals. RESEARCH QUESTION: What is the effect on intensity measures when using cadence cut point criteria derived from overground and treadmill walking and does predicted VO2 max correlate with exercise related community activity in a typically developing population? METHODS: A group of 37 typically developing participants between 8 and 27 years of age, underwent a graded submaximal VO2 testing protocol followed by a typical week of community ambulation, recorded with a step activity monitor. Maximum cadence criteria established during overground and treadmill walking were applied and the data were compared. The weekly step activity variables included: total steps, total ambulatory time, intensity, duration, and volume. Predicted VO2 Max was calculated, and correlations calculated to step activity outputs. RESULTS: Results showed significant differences (p<0.001) between cadence cut point criteria across all intensity measures except in the amount of time spent in the 30-60 % intensity category (p=0.182). Predicted VO2 max did not significantly correlate with step activity outputs related to exercise (moderate+ intensity and long duration ambulatory bouts; p>0.277). SIGNIFICANCE: This study illustrates the importance of close consideration in applying recommended cut off criteria when assessing intensity outputs from step activity data. Cadence from both overground and treadmill walking were collected in a controlled lab setting, but the influence of the treadmill mechanical and forced cadence criteria must be considered when selecting intensity cut points.

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Vanadium dioxide has attracted much interest due to the drastic change of the electrical and optical properties it exhibits during the transition from the semiconductor state to the metallic state, which takes place at a critical temperature of about 68 °C. Much study has been especially devoted to developing advanced fabrication methodologies to improve the performance of VO2 thin films for phase-change applications in optical devices. Films structural and morphological characterisation is normally performed with expensive and time consuming equipment, as x-ray diffractometers, electron microscopes and atomic force microscopes. Here we propose a purely optical approach which combines Polarized Raman Mapping and Phase-Transition by Continuous Wave Optical Excitation (PTCWE) to acquire through two simple measurements structural, morphological and thermal behaviour information on polycrystalline VO2 thin films. The combination of the two techniques allows to reconstruct a complete picture of the properties of the films in a fast and effective manner, and also to unveil an interesting stepped appearance of the hysteresis cycles probably induced by the progressive stabilization of rutile metallic domains embedded in the semiconducting monoclinic matrix.

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PURPOSE: Fat free mass (FFM) is considered the metabolically active component of human body and is positively associated with maximal oxygen uptake ( VO 2 max ). However, FFM is composed of metabolically active and inactive subcomponents whose proportion can vary depending on body composition and clinical condition, possibly affecting such association. Although it is known that in facioscapulohumeral dystrophy (FSHD) peculiar changes in body composition occur, it is unclear whether there are alterations in FFM composition and, if so, whether such alterations affect the association towards VO 2 max compared to healthy subjects (HS). METHODS: To address this issue, 27 FSHD patients (mean age 37.3; 9 female) and 27 sex and age matched HS, underwent an assessment of VO 2 max by cardiopulmonary exercise tests (CPET) and body composition, with reference to FFM and its subcomponents, by bioimpedance analysis. RESULTS: In between-groups comparison, patients showed lower amounts of body cell mass (BCM) and intracellular water (ICW) which reflect in lower BCM/FFM ratio and higher extracellular to intracellular water ratio (ECW/ICW). Patients' VO 2 max was lower than HS and, even if with lower associative values than HS, correlated with FFM and BCM, while BCM/FFM and ECW/ICW ratios associations were observed only in HS. CONCLUSION: FSHD patients showed lower amount of BCM and ICW. BCM resulted as the parameter with the highest associative value with VO2max in both groups. Since VO 2 max is associated with functional ability in dystrophic patients, BCM, rather than FFM, could be an additional body composition-based clinical stratification factor.

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Chest deformities in children with scoliosis may result in cardiopulmonary disorders, lowering cardiopulmonary capacity levels. However, results regarding the dependence of cardiopulmonary capacity on the severity level of scoliosis remain controversial. We aimed to use dynamic cardiopulmonary exercise testing (CPET) to investigate exercise capacity in reference to spinal deformity in patients with mild or moderate idiopathic scoliosis by means of multivariate analyses. Methods: We included 92 children and adolescents aged 10-17 years with mild and moderate idiopathic scoliosis and 94 healthy peers. The study consisted of three parts: (1) medical record analyses; (2) anthropometric measurements; and (3) CPET. Results: Our results revealed that the mean VO2peak and VO2peak/kg values of the participants with scoliosis were 0.27 L/min and 0.37 mL/min/kg lower than their healthy peers, respectively, regardless of age and gender. Furthermore, the occurrence of scoliosis correlates with a mean decrease in minute ventilation volume by 10.10 L/min, tidal volume by 0.11 L, breathing frequency by 3.78 bpm, and breathing reserve by 14.34%, regardless of the age and gender of the participants. Children and adolescents with mild-to-moderate scoliosis during CPET exhibit a lower ventilation capacity and lower VO2 max than healthy adolescents matched in age but their cardiorespiratory fitness parameters do not depend on the Cobb angle value and the angle rotation of the primary spinal curvature. Conclusions: Physical therapy and activity should be recommended to prevent cardiorespiratory failure in later life in patients with scoliosis. This study may also provide CPET reference values for healthy children and adolescents with scoliosis.

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Based on the unique insulator-metal phase transition property of vanadium dioxide (VO2), we propose an integrated metasurface with a switchable mechanism between ultra-broadband absorption and polarization conversion, operating in the terahertz (THz) frequency range. The designed metasurface device is constructed using a stacked structure composed of VO2 quadruple rings, a dielectric layer, copper stripes, VO2 film, a dielectric layer, and a copper reflection layer. Our numerical simulations demonstrate that our proposed design, at high temperatures (above 358 K), exhibits an ultra-broadband absorption ranging from 4.95 to 18.39 THz, maintaining an absorptivity greater than 90%, and achieves a relative absorption bandwidth of up to 115%, significantly exceeding previous research records. At room temperature (298 K), leveraging VO2's insulating state, our proposed structure transitions into an effective polarization converter, without any alteration to its geometry. It enables efficient conversion between orthogonal linear polarizations across 3.51 to 10.26 THz, with cross-polarized reflection exceeding 90% and a polarization conversion ratio over 97%. More importantly, its relative bandwidth reaches up to 98%. These features highlight its wide-angle, extensive bandwidth, and high-efficiency advantages for both switching functionalities. Such an ultra-broadband convertible design offers potential applications in optical switching, temperature dependent optical sensors, and other tunable THz devices in various fields.

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Introduction: Advanced heart failure (HF) is an epidemic that affects multiple organ systems with high morbidity and mortality rates despite optimal medical therapy (OMT) and remains the leading cause of hospitalizations in type 2 diabetes-related cardiovascular disease. The addition of sodium-glucose co-transporter inhibitors (SGLT2i) in treating these patients has seen improved mortality and hospital admission rates. As such, we felt it was important to investigate whether the use of SGLT2i improved functional capacity in patients with HF when compared to OMT by evaluating maximum oxygen consumption (peak VO2) using cardiopulmonary exercise testing (CPET). Methods: We found 94 heart failure patients between August 2020 and August 2021 who underwent CPET before and after treatment at Mayo Clinic in Florida. 50 patients received OMT and 44 received OMT and SGLT2i therapy. CPET results before and after were compared for each group. Results: The baseline ejection fraction was not significantly different between groups, with the OMT group at 38% and the SGLT2i group at 33%, p = 0.10. OMT patients were found to have a significantly lower hemoglobin A1c of 5.7 (5.4-6.1) compared to those with SGLT2i therapy of 6.4 (5.8-7.1), p = 0.01. The baseline peak VO2 was 17.3 ml/kg/min (13.3-21.6) in the OMT group and 17.3 ml/kg/min (14.4-18.9) in the SGLT2i group, p = 0.18, not significantly different. The interesting finding is that the follow-up peak VO2 at one year for the OMT group was 17 ml/kg/min (13.3-21.6), which was not significantly different from the SGLT2i group peak VO2 of 17 ml/kg/min (14.6-19.6), p = 0.19. Our study is the first to compare before and after peak VO2 values of the OMT+SGLT2i group to the patient's own baseline and we found no significant improvement. Conclusion: Our single-center data shows no improvement in functional capacity after the addition of SGLT2i therapy to OMT in patients with advanced heart failure. Improved hospitalization and symptoms may be attributed to other numerous effects of SGLT2i such as volume management.

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Physical activity promotes metabolic health and prevents lifestyle-related diseases. Adiponectin is specifically produced by adipose tissue and comes in three forms, differing in terms of weight: trimers (LMW), hexamers (MMW), and high-molecular-weight (HMW) oligomers. The oligomers are associated with the beneficial effects of adiponectin. In this study, we aimed to investigate the impact of a single bout of exhaustive exercise on adiponectin expression in 25 male amateur athletes, divided into two groups, one comprising young adults (YAs) (n = 15), and the other comprising middle-aged adults (MAs) (n = 10). Body fat was estimated through skinfold thickness. Adiponectin levels were assessed at baseline and at 15 min and 24 h post-exercise, while HMW oligomer levels were evaluated at baseline and at 24 h post-exercise. We observed a significant increase in total adiponectin at both 15 min and 24 h after exercise, with there being a more evident effect among the YA subjects. HMW oligomers also increased significantly after exercise both in the total sample and among the YA subjects, but this was not the case in the MA subjects. The increase in adiponectin levels was significantly associated with Powerpeak. Furthermore, a significant inverse correlation was found between basal adiponectin and VO2peak and Powerpeak. In conclusion, a single bout of exhaustive exercise can rapidly and significantly enhance the basal circulating adiponectin concentration, which seems to be negatively associated with maximal aerobic capacity.

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This review investigates the effect of two different concurrent training sequences on endurance performance. The sequences investigated are Endurance-Resistance (ER) and Resistance-Endurance (RE). A literature search is conducted of the SPORTDiscus and Medline databases. The included studies are randomized control trials, which compare the effect of ER and RE on at least one endurance performance variable. A PEDro scale is used to assess the methodological quality of the articles in this review. Of a total of 152 articles identified during the initial screening, 15 studies meet the inclusion criteria. These studies include 426 participants (298 males and 128 females), with 212 of the participants training with ER and 214 with RE. The results are presented as the percentage change of the mean from pre- to post-test. All the studies show an improvement in endurance from pre to post for both interventions, except for the RE group in one study. This review finds small and non-conclusive sequence effects between ER and RE, suggesting that the sequence of concurrent training is not of great importance in relation to endurance performance.

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Sickle cell disease (SCD) is characterized by central (cardiac) and peripheral vascular dysfunctions, significantly diminishing exercise capacity and quality of life. While central cardiopulmonary abnormalities in SCD are known to reduce exercise capacity and quality of life; the impact of hemolysis and subsequent cell-free hemoglobin (Hb)-mediated peripheral vascular abnormalities on those outcomes are not fully understood. Despite the recognized benefits of exercise training for cardiovascular health and clinical management in chronic diseases like heart failure, there remains substantial debate on the advisability of regular physical activity for SCD patients. This is primarily due to concerns that prolonged and/or high-intensity exercise might trigger metabolic shifts leading to vaso-occlusive crises. As a result, exercise recommendations for SCD patients are often vague or nonexistent, reflecting a gap in knowledge about the mechanisms of exercise intolerance and the impact of exercise training on SCD-related health issues. This mini-review sheds light on recent developments in understanding how SCD affects exercise tolerance, with a special focus on the roles of hemolysis and the release of cell-free hemoglobin in altering cardiovascular and skeletal muscle function. Also highlighted here is the emerging research on the therapeutic effects and safety of exercise training in SCD patients. Additionally, the review identifies future research opportunities to fill existing gaps in our understanding of exercise (in)tolerance in SCD.

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Background: Health-related fitness directly depends on the level of physical activity of the individual. Inactivity contributes to around 3.3% of all deaths, making the lack of exercise and sedentary lifestyles among the young generation a current source of concern. There is a paucity of research on the association between PA and health-related physical fitness among young people. In the perspective of this, the objective of this research was to find out the effect of PA levels on physical fitness in healthy adults. Methodology: A total of 419 students between the ages of 18 and 25 participated in this cross-sectional survey. The "Global Physical Activity Questionnaire (GPAQ)" was used to evaluate the PA. Their body fat percentage was measured using a skin fold caliper, followed by measurement of VO2max using a gas analyzer and hand grip strength and endurance assessment with the help of a computerized dynamometer. For statistical analysis, Karl Pearson's correlation coefficients and the ANOVA test were utilized. Results: PA was positively correlated with VO2 max (r=0.429), and handgrip strength (r=0.408) while negatively correlated with body fat % (r=-.315). VO2 max, body fat, and hand grip strength differ significantly amongst participants having different physical activity levels. (p-value =<0.05). Conclusion: This research concludes that PA is associated with physical fitness. PA will lead to a definite improvement in overall physical fitness. With the help of the results of this study, young adults can be motivated for physical fitness.