Evaluation of the shear stability of aerobic granular sludge from a pilot-scale membrane bioreactor: Establishment of a quantitative method.

This work established a quantitative method to access the shear stability of aerobic granular sludge (AGS) and validated its feasibility by using the mature AGS from a pilot-scale (50 tons/day) membrane bioreactor (MBR) for treating real municipal wastewater. The results showed that the changing rate (ΔS) of the peak area (S) of granule size distribution (GSD) exhibited an exponential relationship (R2≥0.76) with the shear time (y=a-b·cx), which was a suitable indicative index to reflect the shear stability of different AGS samples. The limiting granule size (LGS) was defined and proposed to characterize the equilibrium size for AGS after being sheared for a period of time, whose value in terms of Dv50 showed high correlation (R2=0.92) with the parameter a. The free Ca2+ (28.44-34.21 mg/L) in the influent specifically interacted with polysaccharides (PS) in the granule's extracellular polymeric substance (EPS) as a nucleation site, thereby inducing the formation of Ca precipitation to enhance its Young's modulus, while Ca2+ primarily interacted with PS in soluble metabolic product (SMP) during the initial granulation process. Furthermore, the Young's modulus significantly affected the parameter a related to shear stability (R2=0.99). Since the parameter a was more closely related (R2=1.00) to ΔS than that of the parameter b or c, the excellent correlation (R2=0.99) between the parameter a and the wet density further verified the feasibility of this method.

Effect of gradual increase of salt on performance and microbial community during granulation process.

Salinity was considered to have effects on the characteristics, performance microbial communities of aerobic granular sludge. This study investigated granulation process with gradual increase of salt under different gradients. Two identical sequencing batch reactors were operated, while the influent of Ra and Rb was subjected to stepwise increments of NaCl concentrations (0-4 g/L and 0-10 g/L). The presence of filamentous bacteria may contribute to granules formed under lower salinity conditions, potentially leading to granules fragmentation. Excellent removal efficiency achieved in both reactors although there was a small accumulation of nitrite in Rb at later stages. The removal efficiencies of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) in Ra were 95.31%, 93.70% and 88.66%, while the corresponding removal efficiencies in Rb were 94.19%, 89.79% and 80.74%. Salinity stimulated extracellular polymeric substances (EPS) secretion and enriched EPS producing bacteria to help maintain the integrity and stability of the aerobic granules. Heterotrophic nitrifying bacteria were responsible for NH4+-N and NO2--N oxidation of salinity systems and large number of denitrifying bacteria were detected, which ensure the high removal efficiency of TN in the systems.

Disentangling microbial coupled fillers mechanisms for the permeable layer optimization process in multi-soil-layering systems.

The multi-soil-layering (MSL) systems is an emerging solution for environmentally-friendly and cost-effective treatment of decentralized rural domestic wastewater. However, the role of the seemingly simple permeable layer has been overlooked, potentially holding the breakthroughs or directions to addressing suboptimal nitrogen removal performance in MSL systems. In this paper, the mechanism among diverse substrates (zeolite, green zeolite and biological ceramsite) coupled microorganisms in different systems (activated bacterial powder and activated sludge) for rural domestic wastewater purification was investigated. The removal efficiencies performed by zeolite coupled with microorganisms within 3 days were 93.8% for COD, 97.1% for TP, and 98.8% for NH4+-N. Notably, activated sludge showed better nitrification and comprehensive performance than specialized nitrifying bacteria powder. Zeolite attained an impressive 89.4% NH4+-N desorption efficiency, with a substantive fraction of NH4+-N manifesting as exchanged ammonium. High-throughput 16S rRNA gene sequencing revealed that aerobic and parthenogenetic anaerobic bacteria dominated the reactor, with anaerobic bacteria conspicuously absent. And the heterotrophic nitrification-aerobic denitrification (HN-AD) process was significant, with the presence of denitrifying phosphorus-accumulating organisms (DPAOs) for simultaneous nitrogen and phosphorus removal. This study not only raises awareness about the importance of the permeable layer and enhances comprehension of the HN-AD mechanism in MSL systems, but also provides valuable insights for optimizing MSL system construction, operation, and rural domestic wastewater treatment.

El trabajo de fuerza muscular en la atención a adultos mayores con sarcopenia

El proceso de envejecimiento está marcado por el sedentarismo y la escasa actividad física, lo que se asocia a la disminución rápida y continua de las capacidades funcionales, la dependencia y la fragilidad. El objetivo del trabajo se orienta a valorar, mediante el test de repeticiones máximas con pesos no extremos, el efecto de la aplicación de ejercicios con pesas para la atención de la sarcopenia. Se aplicaron métodos de los niveles teóricos y empíricos como el analítico, sintético, inductivo, deductivo, revisión documental, análisis documental, observación, encuesta y entrevista. Se aplicó, como instrumento de trabajo, una batería de ejercicios físicos de resistencia a la fuerza, y aeróbicos que permitieron utilizar el método de medición en siete adultos mayores con sarcopenia, atendidos en el Centro de Actividad Física y Salud de la Universidad de las Ciencias de la Cultura Física y Deportes ¨ Manuel Fajardo. Se evaluó el trabajo de fuerza muscular mediante el test mencionado, lo que permitió identificar el peso real de la carga física con la que deben entrenar y, sobre esa base, se elaboró la batería de ejercicios con pesas. En los resultados preliminares registrados, mediante la aplicación del test, se constató que la integración del trabajo con pesas y el aeróbico influyen de manera favorable en la ganancia de fuerza en el adulto mayor.

O processo de envelhecimento é marcado por um estilo de vida sedentário e pouca atividade física, o que está associado ao declínio rápido e contínuo das capacidades funcionais, à dependência e à fragilidade. O objetivo do trabalho visa avaliar, por meio do teste de repetições máximas com pesos não extremos, o efeito da aplicação de exercícios com carga no tratamento da sarcopenia. Foram aplicados métodos dos níveis teórico e empírico como analítico, sintético, indutivo, dedutivo, revisão documental, análise documental, observação, levantamento e entrevista. Como instrumento de trabalho foi aplicada uma bateria de exercícios físicos resistidos de força e aeróbios que permitiu a utilização do método de mensuração em sete idosos com sarcopenia atendidos no Centro de Atividade Física e Saúde da Universidade de Ciências da Cultura Física e. Desporto ¨ Manuel Fajardo. O trabalho de força muscular foi avaliado por meio do referido teste, que possibilitou identificar o real peso da carga física com a qual devem treinar e, com base nisso, foi desenvolvida a bateria de exercícios com pesos. Nos resultados preliminares registrados, por meio da aplicação do teste, foi confirmado que a integração do trabalho com pesos e do trabalho aeróbio influencia favoravelmente o ganho de força em idosos.

The aging process is marked by a sedentary lifestyle and little physical activity, which is associated with the rapid and continuous decline in functional capacities, dependency and fragility. The objective of the work is aimed at assessing, through the test of maximum repetitions with non-extreme weights, the effect of the application of exercises with weights for the care of sarcopenia. Methods from the theoretical and empirical levels such as synthetic analytical, inductive-deductive, documentary review, documentary analysis, observation, survey and interview were applied. As a working instrument, a set of strength endurance and aerobic physical exercises was applied that allowed the measurement method to be used in seven older adults with sarcopenia, treated at the Center for Physical Activity and Health of the University of Sciences. of Physical Culture and Sports ¨Manuel Fajardo¨. The muscular strength work was evaluated using the aforementioned test, which made it possible to identify the real weight of the physical load with which they must train and, on that basis, the set of exercises with weights was developed. In the preliminary results recorded, through the application of the test, it was confirmed that the integration of weight work and aerobic work favorably influences strength gain in the older adults.

MR Assessment of Acute Changes of Cerebral Perfusion, Metabolism, and Blood-Brain Barrier Permeability in Response to Aerobic Exercise.

BACKGROUND: It remains unclear how a single bout of exercise affects brain perfusion, oxygen metabolism, and blood-brain barrier (BBB) permeability. Addressing this unresolved issue is essential to understand the acute changes in cerebral physiology induced by aerobic exercise. PURPOSE: To dynamically monitor the acute changes in cerebral physiology subsequent to a single aerobic exercise training session using noninvasive MRI measurements. STUDY TYPE: Prospective. POPULATION: Twenty-three healthy participants (18-35 years, 10 females/13 males) were enrolled and divided into 10-minute exercising (N = 10) and 20-minute exercising (N = 13) groups. FIELD STRENGTH/SEQUENCE: 3.0 T/Phase Contrast (PC) MRI (gradient echo), T2-Relaxation-Under-Spin-Tagging (TRUST) MRI (gradient echo EPI), Water-Extraction-with-Phase-Contrast-Arterial-Spin-Tagging (WEPCAST) MRI (gradient echo EPI) and T1-weighted magnetization-prepared-rapid-acquisition-of-gradient-echo (MPRAGE) (gradient echo). ASSESSMENT: A baseline MR measurement plus four repeated MR measurements immediately after 10 or 20 minutes moderate running exercise. MR measurements included cerebral blood flow (CBF) as measured by PC MRI, venous oxygenation (Yv) and cerebral metabolic rate of oxygen (CMRO2) as assessed by TRUST MRI, water extraction fraction (E), and BBB permeability-surface-area product (PS) as determined by WEPCAST MRI. STATISTICAL TESTS: The time dependence of the physiological parameters was studied with a linear mixed-effect model. Additionally, pairwise t-tests comparison of the physiological parameters at each time point was conducted. A P-value of <0.05 was considered statistically significant. RESULTS: There was an initial drop (8.22 ± 2.60%) followed by a recovery in CBF after exercise, while Yv revealed a significant decrease (6.37 ± 0.92%), i.e., an increased oxygen extraction, and returned to baseline at later time points. CMRO2 showed a trend of increase (5.68 ± 3.04%) and a significant interaction between time and group. In addition, E increased significantly (3.86% ± 0.89) and returned to baseline level at later time points, while PS remained elevated (13.33 ± 4.79%). DATA CONCLUSION: A single bout of moderate aerobic exercise can induce acute alterations in cerebral perfusion, metabolism, and BBB permeability. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.

Hybrid Training System Consisting of Synchronized Neuromuscular Electrical Stimulation for Voluntary Exercise Using an Articular Motion Sensor.

Neuromuscular electrical stimulation (NMES) is widely used for improving muscle strength, preventing muscle atrophy, and decreasing pain. Recently, NMES has become a substitute for exercise therapy for metabolism improvement and functional capacity improvement. However, NMES has several disadvantages. First, slow-twitch muscle contractions are insufficient because the recruitment pattern of NMES does not obey Henneman's size principle. Second, when using surface electrodes, it is difficult to contract deep skeletal muscles at the application site. Third, electrical stimulation causes discomfort. Therefore, we devised a simultaneous combination of NMES and voluntary muscle contractions to overcome the weak points of NMES. A hybrid training system (HTS) that resists the motion of a volitionally contracting agonist muscle with force generated by its electrically stimulated antagonist was developed as a technique to combine the application of NMES and volitional contractions. This motion sensor makes it possible to simultaneously combine voluntary movements with NMES. Our HTS synchronizes with voluntary movements, enhancing safety and reducing discomfort. This HTS enhances the exercise effect of even simple exercise. So far, our HTS has been reported to be effective for muscle strength enhancement, prevention of muscle atrophy, improvement of physical function, pain relief, enhancement of physical fitness, and improvement of metabolic function. HTS are expected to be useful methods in environments where sufficient exercise load is not available or for individuals with low exercise tolerance.

STAT3 drives the expression of HIF1alpha in cancer cells through a novel super-enhancer.

Aerobic glycolysis is one of the major hallmarks of malignant tumors. This metabolic reprogramming benefits the rapid proliferation of cancer cells, facilitates the formation of tumor microenvironment to support their growth and survival, and impairs the efficacy of various tumor therapies. Therefore, the elucidation of the mechanisms driving aerobic glycolysis in tumors represents a pivotal breakthrough in developing therapeutic strategies for solid tumors. HIF1α serves as a central regulator of aerobic glycolysis with elevated mRNA and protein expression across multiple tumor types. However, the mechanisms contributing to this upregulation remain elusive. This study reports the identification of a novel HIF1α super enhancer (HSE) in multiple cancer cells using bioinformatics analysis, chromosome conformation capture (3C), chromatin immunoprecipitation (ChIP), and CRISPR/Cas9 genome editing techniques. Deletion of HSE in cancer cells significantly reduces the expression of HIF1α, glycolysis, cell proliferation, colony and tumor formation ability, confirming the role of HSE as the enhancer of HIF1α in cancer cells. Particularly, we demonstrated that STAT3 promotes the expression of HIF1α by binding to HSE. The discovery of HSE will help elucidate the pathways driving tumor aerobic glycolysis, offering new therapeutic targets and potentially resolving the bottleneck in solid tumor treatment.

Mechanisms underlying the detrimental impact of micro(nano)plastics on the stability of aerobic granular sludge: Interactions between micro(nano)plastics and extracellular polymeric substances.

Microplastics (MPs) and nanoplastics (NPs) present in wastewater can pose a negative impact to aerobic granular sludge (AGS). Herein, this study found that MPs and NPs (20 mg/L) deteriorated the sludge settleability and granule integrity, resulting in a 15.7 % and 21.9 % decrease in the total nitrogen removal efficiency of the AGS system, respectively. This was possibly due to the reduction of the extracellular polymeric substances (EPS) content. The subsequent analysis revealed that tyrosine, tryptophan, and humic acid-like substances in EPS exhibited a higher propensity for chemisorption and inhomogeneous multilayer adsorption onto NPs compared to MPs. The binding of EPS onto the surface of plastic particles increased the electronegativity of the MPs, but facilitated the aggregation of NPs through reducing the electrostatic repulsion, thereby mitigating the adverse effects of MPs/NPs on the AGS stability. Additionally, comprehensive analysis of the extended Derjaguin-Landau-Verwey-Overbeek theory indicated that the suppressed aggregation of microorganisms was the internal mechanisms contributing to the inadequate stability of AGS induced by MPs/NPs. This study provides novel insights into the detrimental mechanisms of MPs/NPs on the AGS stability, highlighting the key role of EPS in maintaining the structural stability of AGS when exposed to MPs/NPs.

Aerobic exercise as a non-pharmacological intervention for improving metabolic and hemodynamic profiles in type 2 diabetes.

BACKGROUND: Type 2 Diabetes Mellitus (T2DM) is a global health concern associated with numerous complications. Aerobic exercise is recognized as a crucial non-pharmacological intervention for T2DM management, but its specific effects on key health parameters warrant further investigation. OBJECTIVE: This study aimed to evaluate the impact of a structured 8-week aerobic exercise program on fasting blood glucose (FBG), glycated haemoglobin (HbA1c), body mass index (BMI), blood pressure (BP), and resting heart rate (RHR) in individuals with T2DM. METHODS: A prospective study was conducted with 100 participants diagnosed with T2DM. The intervention group (n = 50) underwent a supervised aerobic exercise program for eight weeks, while the control group (n = 50) received no structured exercise intervention. Pre- and post-intervention assessments were conducted to measure FBG, HbA1c, BMI, BP, RHR, and VO2 max were taken. RESULTS: The aerobic group exhibited a significant reduction in FBG, declining from 141 to 132 mg/dl. Correspondingly, HbA1c decreased from 7.93 to 7.15%. Additionally, the aerobic group demonstrated a notable decrease in RHR from 72 to 66 bpm, indicating improved cardiovascular fitness. Concurrently, VO2 max increased from 22 to 26 mL/kg/min, further supporting the enhancement of cardiorespiratory capacity. Trends toward improvement were also observed in SBP and DBP. Correlation analysis revealed significant relationships between various health parameters, highlighting the interconnectedness of these variables in T2DM management. CONCLUSIONS: This study provides robust evidence supporting the benefits of aerobic exercise in individuals with T2DM. The improvements in glycemic control, blood pressure, and cardiorespiratory fitness underscore the importance of incorporating structured exercise programs into diabetes management protocols. The results emphasize the importance of incorporating regular physical activity into diabetes management strategies to optimize health outcomes and reduce the risk of complications.

Degradation of paper-based boxes for food delivery in composting and anaerobic digestion tests.

This study evaluated the fate of food delivery boxes when subjected to biological treatments, reproducing at the lab-scale the conditions of full-scale plants. Four paper-based boxes were composted: two made of paper only, one coupled with polylactic acid (PLA), and one with a barrier coating. One paper only box and the box with PLA were also investigated for their anaerobic degradability with biochemical methane potential (BMP) and semi-continuous tests. During composting, the boxes were not recognisable inside the compost after four (paper only boxes), eight (box with PLA), and twelve (box with barrier coating) weeks. In BMP tests, the paper only box showed a degradability similar to that of food waste (92 %), while the box with PLA degraded only at 76 %. Furthermore, undigested pieces of PLA were found in semi-continuous tests. Accordingly, paper resulted suitable for biological treatments, while the presence of PLA or other barrier coatings can be critical.

Genomic analysis and metabolic characteristics provide insights into inorganic nitrogen metabolism of novel bacterium Acinetobacter pittii J08.

A novel A. pittii J08 with heterotrophic nitrification and aerobic denitrification (HN-AD) isolated from pond sediments could rapidly degrade inorganic nitrogen (N) and total nitrogen (TN-N) with ammonium (NH4+-N) preference. N degradation rate of NH4+-N, nitrite (NO2--N) and nitrate (NO3--N) were 3.9 mgL-1h-1, 3.0 mgL-1h-1 and 2.7 mgL-1h-1, respectively. In addition, strain J08 could effectively utilize most of detected low-molecular-weight carbon (LMWC) sources to degrade inorganic N with a wide adaptability to various culture conditions. Whole genome sequencing (WGS) analysis revealed that assembled genome of stain J08 possessed the crucial genes involved in dissimilatory/assimilatory NO3--N reduction and NH4+-N assimilation. These results indicated that strain J08 could be applied to wastewater treatment in aquaculture.

The effects of combining visual-auditory stimuli with exercise on short-term affect improvement: a randomized controlled trial.

ABSTRAC T: Prior research has explored the effects of engaging with real or virtual natural landscapes and listening to music during aerobic exercise on short-term affect, however, the specific differences in the improvement of short-term affect by different combinations of Virtual Reality (VR) and music rhythm require further investigation. The objective of this study is to investigate the effects of various combinations of VR and music on short-term mood, thereby providing a reference for future research on public fitness. This study recruited 132 valid participants (mean age 24.0 ± 0.9 years), with a gender distribution of 68 males and 64 females. Participants were randomly assigned to one of four groups: Visual-Music (V-M), Music-Visual (M-V), Visual-only (V), and Music-only (M). The exercise mode was 15 min of aerobic power cycling with 2 min of low-intensity power cycling intervals in the middle. After the exercise, the participants were asked to sit and then performed either a VR intervention or a music intervention for 15 min. The collected indicators included blood pressure, positive/negative affect, and heart rate variability indicators (RMSSD, SDNN, LF/HF). Data analysis included descriptive statistics, repeated measures ANOVA, and multifactor ANOVA. The effect of different VR and Music combined with exercise interventions on the improvement of short-term affect was analyzed based on the effect size (ɳp2) and combined with the significance p-value. Intra-group results showed that DBP, positive and negative affect, SDNN, RMSSD indicators in V-M group were significant differences (p < 0.05), while SBP, positive affect, negative affect, SDNN, RMSSD, LF/HF indicators in M-V group were significant differences (p < 0.05). Only SDNN and RMSSD indicators in M group had significant differences (p < 0.05), and only SBP and RMSSD indicators in V group had significant differences (p < 0.05). The results between groups showed that only SDNN and LH/HF groups had a significant difference (p < 0.05), other indicators had a trend of improvement or positive promotion to a certain extent, but the statistical difference was not significant (p > 0.05). Aerobic exercise with consistent intensity and the combined visual-auditory interventions (M-V and V-M) significantly improved blood pressure, and the short-term affect of physiological responses (LF/HF, SDNN, RMSSD), along with subjective affect measures, compared to other groups. These findings suggest that incorporating VR and music with exercise can effectively enhance short-term affect, recommending an integrated approach to aerobic exercise and relaxation through music and visual exposure to natural environments.

Effects of physical training on coagulation parameters, interleukin-6, and angiotensin-converting enzyme-2 in COVID-19 survivors.

COVID-19 is a highly contagious virus that uses Angiotensin-converting enzyme 2 (ACE2) as a receptor to enter human cells. The virus leads to an increase in inflammatory cytokines (i.e. IL-6) and an impaired coagulation system, which can cause serious complications during and after the disease. Physical exercise has been shown to improve COVID-19 complications through various mechanisms, such as modulation of the immune and coagulation systems. Therefore, this study investigated the effects of 8 weeks of training on inflammatory, coagulation, and physical factors in patients with COVID-19 during the recovery phase. Twenty-seven male and female volunteers (age 20-45 years) who recently recovered from COVID-19 were assigned to the control (n = 13) or the training group (n = 14). Blood samples, aerobic capacity and muscle endurance were collected 24 h before the start of the interventions and 24 h after the final training session in week 4 and 48 h after the final training session in week 8. IL-6, ACE2, fibrinogen, and D-dimer were measured using ELISA. The training group showed a significant increase in muscle endurance (p = 0.004) and aerobic capacity (p = 0.009) compared to the control group. Serum levels of IL-6 and fibrinogen decreased in the training group but this decrease was not statistically significant (p > 0.05). Despite a slight increase in the quality of life and sleep in the training group, no statistically significant difference was observed between the training and the control group. It appears that physical training has beneficial effects on the coagulation system, inflammatory factors, and sleep quality and can facilitate the recovery of COVID-19 patients.

The Effect of Aerobic Exercise on Visuospatial Attention in Young Adults.

Our objective in this study was to investigate the effect of moderate-intensity aerobic exercise on visuospatial attention bias. We examined line bisection performance at rest before exercise and then immediately after exercise in 20 young adults. Pre-exercise, there was a larger leftward bias in subjective midpoint judgment of all participants than post-exercise (p < .001). Thus, leftward error magnitude decreased according to aerobic exercise, as there were rightward shifts after the exercise. The participants' performancse were modulated by the hand used to perform manual bisection tasks (p < .02). Participants erred to the left of the true midpoint with the non-dominant hand and to the right of the true midpoint with the dominant hand. The use of the non-dominant hand led to greater leftward error than the errors obtained using the dominant hand, though there was no interaction effect between hand use and effort. These findings suggest that moderate aerobic exercise can benefit visuospatial attention in adults.

Enhancing cognitive performance and mitigating dyslipidemia: the impact of moderate aerobic training on sedentary older adults.

BACKGROUND: The present study aimed to evaluate the effects of 24 weeks of moderate aerobic exercise on lipids and lipoprotein levels; Lipo (a) markers, and their association with cognitive performance in healthy older adults. METHODS: A total of 150 healthy subjects (100 males and 50 females; age range: 65-95 years) were recruited for this study. Based on the LOTCA test score, subjects were classified into two groups: the control group (n = 50) and the cognitive impairment group (n = 100). Cognitive functioning, leisure-time physical activity (LTPA), lipid profile, total cholesterol, TG, HDL-c, LDL-C, and lipo(a) were assessed at baseline and post-24-week aerobic exercise interventions using LOTCA battery, pre-validated Global Physical Activity Questionnaire (GPAQ) version II, colorimetric, and immunoassay techniques, respectively. RESULTS: Significant improvements in cognitive function and modulation in lipid profile and lipoprotein (a) markers were reported in all older subjects following 24 weeks of moderate exercise. LOTCA-7-sets scores significantly correlated with physical activity status and the regulation of lipids and Lipo (a) markers. Physically active persons showed higher cognitive performance along with a reduction in the levels of T-Cholest., TG, LDL-C, Lipo (a), and an increase in the levels of HDL-C and aerobic fitness VO2max compared with sedentary participants. Cognitive performance correlated positively with increased aerobic fitness, HDL-C, and negatively with T-Cholest., TG, LDL-C, and Lipo (a). However, a significant increase in the improvement of motor praxis, vasomotor organization, thinking operations, attention, and concentration were reported among older adults. CONCLUSIONS: The study findings revealed that supervised moderate aerobic training for 24 weeks significantly enhances cognitive functions via mitigating older adults' lipid profiles and lipoprotein (a). Cognitive performance is positively correlated with aerobic fitness and HDL-C level and negatively with T-Cholest., TH, LDL-C, and Lipo (a).

Cardiorespiratory and aerobic demands of squat exercise.

Squatting, a traditional resistance exercise classified as strength training, relies on anaerobic pathways, but its aerobic aspects remain unclear. We examined heart rate and oxygen demand during squats, exploring variations across different strength statuses. It fills gaps in understanding the cardiorespiratory effects of squatting, especially during multiple sets. Twenty-two young healthy resistance trained men (age: 28 ± 4 years) participated. Maximal oxygen consumption (V̇O2max) and 1 repetition maximum (RM) of squat were measured. Participants performed 5 sets of squat exercises at 65% of 1RM for 10 repetitions with 3-min rest intervals. Heart rate and pulmonary gas exchange were measured during the squat exercise. Participants were divided into high strength (HS; upper 50%) and low strength (LS; lower 50%) groups based on a median split of their 1 RM squat values (normalized to their body weight). During 5 sets of squat exercise, oxygen consumption (V̇O2) increased up to 47.8 ± 8.9 ml/kg/min, corresponding to 100.6% of predetermined V̇O2max. The HS group achieved a greater highest point of V̇O2 in relation to V̇O2max than the LS group (108.0 vs. 93.7%). During the exercise intervals, V̇O2 exceeded V̇CO2, while during the rest intervals, V̇CO2 surpassed V̇O2. Our findings suggest that the oxygen demand during squatting is notably substantial, which may vary according to the training status.

Influence of coping with stressful situations on changes in aerobic capacity and post-workout restitution coefficient in the period of immediate preparation for the European men's cadet wrestling championship.

Aim of the study: The research goal of the study was to determine the relationship between coping with stressful situations and the level of aerobic capacity and post-workout restitution, as well as the changes that occur between these variables through the period of training camp preceding international men's championship competitions in age cadet. Two research hypotheses were verified. The athletes will maintain or improve the results obtained in the performance test and the post-workout restitution coefficient during the immediate preparation period for the European Championships (H1), and the style of coping with stressful situations significantly affects changes in aerobic capacity and the post-workout restitution coefficient during the immediate preparation period for the European Championships (H2). Materials and methods: The athletes of the National Men's Team of Poland in classical style wrestling (n = 16). Coping with stressful situations was examined using the Coping Inventory for Stressful Situations (CISS). Aerobic capacity was analyzed using the Maximal Multistage 20-m Shuttle Run Test. The level of post-exercise restitution was calculated using the Klonowicz coefficient of restitution. Results: There was a significant increase in aerobic capacity levels (p < 0.001), a decrease in resting HR (p < 0.002), HR 1' after the test (p < 0.0031), and HR 5' after the test (p < 0.007). There was a significant correlation between emotional coping style and avoidant style focused on looking for social contacts vs. HR 3' after the test and (r = 0.60; p < 0.015) and HR 5' after the test (r = 0.57; p < 0.020). In addition, a correlation was noted between avoidant style and maximum aerobic speed (r = -0.64; p < 0.008), and avoidant style focused on substitute activities vs. distance and maximum aerobic speed (r = -0.72; p < 0.002). Conclusion: It is reasonable to implement psychological training and regular monitoring of mental preparation in the national men's team training program for athletes competing in wrestling.

Parkinson's Critical Heart Rate Test: Applying the Critical Power Model for People with Parkinson's Disease.

Aerobic exercise with the correct intensity can attenuate motor and non-motor symptoms of Parkinson's disease (PD) and improve the quality of life. However, a specific, validated, non-invasive, and outside the laboratory protocol that assesses physiological variables to prescribe optimal aerobic exercise intensity for people with PD is nonexistent. Therefore, this study aimed to propose a protocol, the Parkinson's critical heart rate test (Parkinson-CHR test), to determine the critical heart rate (CHR) in individuals with PD and verify its validity, reliability, and sensitivity. Fifteen people with idiopathic PD, who were able to practice exercises, were recruited to participate in the study (71.1 ± 6.6 years). The study consisted of two experiments: i) the first one aimed to assess the validity and reliability of the protocol, with participants performing the test twice at a one-week interval; ii) the second experiment aimed to investigate the protocol sensitivity, with individuals being evaluated before and after an 8-week training program according to Parkinson-CHR intensity. In experiment 1, no differences between test and retest were observed in the time to cover the distances (400, 800 and 1200 m), the total heart rate, the critical heart rate, and critical speed (p > 0.05). In experiment 2, there was a reduction in time to cover 400 and 800 m as well as in the total heart rate for all distances after the 8-week training program. The Parkinson-CHR test is a reliable, reproducible, inexpensive, and non-invasive protocol to assess, prescribe, and monitor aerobic exercise intensity in people with PD.

Remote Exercise Training Intervention During the COVID-19 Pandemic: Randomized Controlled Trial.

BACKGROUND: Societal measures to contain the spread of COVID-19 (eg, lockdown and contact restrictions) have been associated with decreased health and well-being. A multitude of prepandemic studies identified the beneficial effects of physical exercise on both physical and mental health. OBJECTIVE: We report on the feasibility of a remote physical exercise intervention and its stress-buffering potential in 2 untrained cohorts: a pre-COVID-19 cohort that completed the intervention in 2019 and a lockdown cohort that started the intervention shortly before pandemic-related restrictions were implemented. METHODS: In a randomized controlled trial, participants were assigned to either an intervention group (IG; pre-COVID-19 cohort: n=7 and lockdown cohort: n=9) or a control group (CG; pre-COVID-19 cohort: n=6 and lockdown cohort: n=6). IG participants received weekly individualized training recommendations delivered via web-based support. The intervention period was initially planned for 8 weeks, which was adhered to in the pre-COVID-19 cohort (mean 8.3, SD 0.5 weeks) but was extended to an average of 17.7 (SD 2.0) weeks in the lockdown cohort. Participants' health parameters were assessed before and after the intervention: aerobic capacity was measured as peak oxygen uptake (VO2peak) via cardiopulmonary exercise testing. Depressive symptoms were scored via the depression subscale of the Brief Symptom Inventory-18. RESULTS: Dropout rates were low in both cohorts in the IG (pre-COVID-19 cohort: n=0, 0% and lockdown cohort: n=2, 16.7%) and the CG (pre-COVID-19 cohort: n=0, 0% and lockdown cohort: n=2, 20%). The mean adherence to the training sessions of the IG for both cohorts was 84% (pre-COVID-19 cohort: SD 5.5% and lockdown cohort: SD 11.6%). Aligned rank transform ANOVAs in the lockdown cohort indicated deterioration of VO2peak and depressive symptoms from before to after the intervention in the CG but no longitudinal changes in the IG. Analyses in the pre-COVID-19 cohort revealed significant increases in VO2peak for the IG compared to the CG (P=.04) but no intervention effects on depressive symptoms. CONCLUSIONS: With low dropout rates and high adherence, the remote intervention was feasible for healthy adults under regular conditions and in the face of pandemic-related stressors. Moreover, our results hint at a stress-buffering effect as well as a buffering of a lockdown-induced deconditioning of remote physical exercise interventions in the pandemic scenario, which can be used in future studies to overcome equally stressful periods of life. However, due to limited statistical power, these findings should be replicated in similar scenarios. TRIAL REGISTRATION: German Clinical Trials Register DRKS00018078; https://drks.de/search/en/trial/DRKS00018078.

Acute aerobic exercise modulates cognition and cortical excitability in adults with attention-deficit hyperactivity disorder (ADHD) and healthy controls.

Evidence suggests aerobic exercise has beneficial effects on cognitive performance in adults with attention-deficit hyperactivity disorder (ADHD). The underlying mechanisms might depend on mechanisms of exercise-mediated brain physiology. The study aims to investigate the effects of acute aerobic exercise on cortical excitability and cognitive performance, and the correlation between these phenomena in adults with ADHD. Twenty-six drug-naïve ADHD adults, and twenty-six age-, and gender-matched healthy controls were assessed with respect to cortical excitability and cognitive performance before and after acute aerobic exercise (a single session for 30 min) or a control intervention. The results show significantly enhanced intracortical facilitation (ICF) and decreased short intracortical inhibition (SICI) after aerobic exercise in healthy subjects. In contrast, SICI was significantly enhanced following acute aerobic exercise in ADHD. In ADHD, furthermore inhibitory control and motor learning were significantly improved after the acute aerobic exercise intervention. Alterations of SICI induced by aerobic exercise, and inhibitory control and motor learning improvement were significantly positively correlated in the ADHD group. Aerobic exercise had partially antagonistic effects in healthy controls, and ADHD patients. Furthermore, aerobic exercise-induced cognition-enhancing effects in ADHD depend on specific alterations of brain physiology, which differ from healthy humans.