Blood Heart Research Articles

Effectiveness of Preoperative Alpha Wave Entrainment in Pediatric Dental Patients: A Randomized Controlled Trial.

Background Pediatric dental anxiety is a significant barrier to effective dental care, necessitating non-pharmacological interventions. Alpha wave entrainment has shown promise in adult studies for reducing procedural anxiety and pain perception, but its effectiveness in pediatric dental settings remains underexplored. Objective This study aims to evaluate the effectiveness of preoperative alpha wave entrainment in alleviating anxiety in gender-specific participants to the interventions. Methods We conducted a randomized controlled trial involving 252 pediatric patients (aged 7-12) with cooperative dispositions. Participants were randomly assigned to either an experimental group receiving alpha wave entrainment or a control group receiving conventional behavior management techniques. The experimental interventioninvolved 10-minute sessions of binaural beats with visualstimulation designed to induce alpha-wave synchronization. Anxiety levels were assessed using physiological measures (heart rate and blood pressure), both pre- and post-interventions. Results The intervention group demonstrated a significant reduction in heart rate and systolic blood pressure post-intervention compared to the control group. These changes indicate a decrease in anxiety levels, with no significant gender differences in the response to the intervention. Conclusion Alpha wave entrainment effectively reduces dental anxiety in pediatric patients, with similar efficacy observed across genders. This study supports the incorporation of alpha wave entrainment into pediatric dental practices as a viable alternative to traditional anxiety management techniques.

The impact of stress on the risk decision-making process.

The effect of stress on risk-taking or risk-averse behavior in decision-making has been inconclusive in previous research, with few studies revealing the underlying neural mechanisms. This study employed event-related potentials technique and combined a social cold pressor assessment test with a mental arithmetic task to induce stress responses, aiming to investigate the influence of exogenous stress on the risk decision-making process. Stress induction results indicated that, in addition to raising heart rate and blood pressure, stress responses were accompanied by enhanced negative emotions, diminished positive emotions, and alterations in neural activity. The outcomes of risk decision-making showed that stress did not significantly affect risk preference or time of choice but did reduce the feedback-related negativity/reward positivity, with a particularly significant effect observed for large outcomes. Stress also altered the amplitude of the P3 component, with stress decreasing the P3 value for winning outcomes relative to losing outcomes. The study suggests that understanding how stress affects risk preference should consider the emotional valence induced by stress. Contrary to the reward sensitivity hypothesis, stress weakened reward sensitivity. Stress led to changes in the allocation of cognitive resources for outcome evaluation: compared to negative outcomes, stress reduced cognitive resources for positive outcomes, which might be related to the enhanced negative emotions induced by stress. The study highlights the importance of focusing on the subjective emotional experience induced by stress in future research on stress and risk decision-making.

Effects of glycopyrrolate and atropine for oral secretions and perioperative hemodynamics in children undergoing tonsillectomy and adenoidectomy: a prospective, single-center, randomized, double-blind, controlled trial

IntroductionGlycopyrrolate is commonly researched as a preoperative medication or in conjunction with cholinesterase inhibitors to counteract the lingering muscarinic effects of non-depolarizing muscarinic agents. However, studies have yielded inconsistent results regarding the superiority of glycopyrrolate over other anti-cholinergic drugs, such as atropine, particularly its effect on heart rate, blood pressure (BP), and glandular secretions. This study aimed to evaluate the differences in perioperative oral secretions, hemodynamics, and recovery quality with glycopyrrolate versus those with atropine before anesthesia induction in children undergoing tonsillectomy and adenoidectomy.MethodsIn this prospective, single-center, randomized, double-blind, controlled trial, a total of 103 children were randomly assigned to group A (n = 51, glycopyrrolate 0.005 mg/kg) or B (n = 52, atropine 0.01 mg/kg). The follow-up anesthetic induction and maintenance protocols were the same in both groups. Vital signs, duration of surgery, extubation time, degree of wetness around the vocal cords during tracheal intubation, weight of oral secretions, and perioperative complications were recorded.ResultsNo significant differences were observed in the degree of wetness around the vocal cords during tracheal intubation, as well as in the weight of oral secretions, duration of surgery, or extubation time, between the two groups. The intraoperative and postoperative heart rates were lower in group A than in group B (110.18 ± 10.58 vs. 114.94 ± 11.14, p = 0.028; 96.96 ± 10.81 vs. 103.38 ± 10.09, p = 0.002). The differences observed in the intraoperative and preoperative heart rates were lower in group A than in group B (23.84 ± 9.62 vs. 29.65 ± 8.75, p = 0.002). The differences observed in the postoperative and preoperative heart rates were lower in group A than in group B (10.63 ± 9.97 vs. 18.09 ± 9.39, p = 0.000).ConclusionGlycopyrrolate showed a smoother change in heart rate than atropine during and after tonsillectomy and adenoidectomy, with no effect on BP or recovery quality, and did not increase oral secretions. The findings indicate that glycopyrrolate can serve as an alternative to atropine to prevent secretions in anesthesia induction for tonsillectomy and adenoidectomy in children.Trial registration: This study was registered with the Chinese Clinical Trial Registry (Registration Number: ChiCTR2200063578; Date of Registration: 12/09/2022).

The prognostic value of HEART score in patients with known heart failure evaluated at the emergency department for acute chest pain

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Heart Lung and Blood Institute (United States). Background Chest pain is a common and concerning symptom in emergency care, often necessities further risk stratification for adverse cardiovascular events on short-term follow up. Patients with known heart failure (HF) constitutes a unique sub-population that would greatly benefit from short-term risk stratification to guide appropriate clinical interventions and optimize resource allocation. HEART (History, ECG, Age, Risk factors, Troponin) is a well-validated risk score that has been shown to outperform other clinical risk scores in patients with chest pain. It remains unknown if HEART score can be safely used in patients with known HF presenting to the emergency department with chest pain. Purpose We sought to evaluate the prognostic value of HEART score in patients with known HF compared to their counterparts. Method This was a prospective observational cohort study of consecutive adult patients evaluated at the emergency department for non-traumatic chest pain. HEART score was computed from charts by independent physician reviewers. The primary study outcome was major adverse cardiac events (MACE) defined as acute coronary syndrome, invasive revascularization, reinfarction, death, cardiac arrest, ventricular tachyarrhythmia, or acute exacerbation within 30 days of indexed admission. Outcomes were adjudicated by two independent reviewers (Kappa = 0.908). Classification performance between groups was compared using area under receiver operator characteristic curve (AUROC), sensitivity, and negative predictive value (NPV). Results Our cohort included 4,132 patients (age 59±16, 47% female, 33% Black). Overall, 921 patients (22.3%) experienced 30-day MACE. The classification performance of HEART score in those without HF (n = 3,329, 81%) was AUROC of 0.831 (95% CI 0.813-0.848), compared to only 0.633 (95% CI 0.592-0.673) in those with known HF (n = 803, 19%) (z score = 8.771, p < 0.001, Figure). The sensitivity and NPV of HEART score among those without HF were 87.4% and 95.3%, compared to 81.2% and 73.3%, respectively, among those with known HF. Conclusion Our findings suggest that the prognostic value of HEART score for predicting 30-day MACE is inferior and suboptimal in patients with known HF evaluated for chest pain at the emergency department compared to their counterparts. These findings emphasize the need for more tailored risk assessment and management strategies in this specific patient population. Further research is warranted to better understand the limitations and potential enhancements of the HEART score in patients with HF.Classification Performance of HEART score

ST-2560, a selective inhibitor of the NaV1.7 sodium channel, affects nocifensive and cardiovascular reflexes in non-human primates.

The voltage-gated sodium channel isoform NaV1.7 is a high-interest target for the development of non-opioid analgesics due to its preferential expression in pain-sensing neurons. NaV1.7 is also expressed in autonomic neurons, yet its contribution to involuntary visceral reflexes has received limited attention. The small molecule inhibitor ST-2560 was advanced into pain behaviour and cardiovascular models to understand the pharmacodynamic effects of selective inhibition of NaV1.7. Potency of ST-2560 at NaV1.7 and off-target ion channels was evaluated by whole-cell patch-clamp electrophysiology. Effects on nocifensive reflexes were assessed in non-human primate (NHP) behavioural models, employing the chemical capsaicin and mechanical stimuli. Cardiovascular parameters were monitored continuously in freely-moving, telemetered NHPs following administration of vehicle and ST-2560. ST-2560 is a potent inhibitor (IC50 = 39 nM) of NaV1.7 in primates with ≥1000-fold selectivity over other isoforms of the human NaV1.x family. Following systemic administration, ST-2560 (0.1-0.3 mg·kg-1, s.c.) suppressed noxious mechanical- and chemical-evoked reflexes at free plasma concentrations threefold to fivefold above NaV1.7 IC50. ST-2560 (0.1-1.0 mg·kg-1, s.c.) also produced changes in haemodynamic parameters, most notably a 10- to 20-mmHg reduction in systolic and diastolic arterial blood pressure, at similar exposures. Acute pharmacological inhibition of NaV1.7 is antinociceptive, but also has the potential to impact the cardiovascular system. Further work is merited to understand the role of NaV1.7 in autonomic ganglia involved in the control of heart rate and blood pressure, and the effect of selective NaV1.7 inhibition on cardiovascular function.

A Novel Approach of Cloud Computing Network for Authentication and Security Enhancement of IoT Enabled Cancer Forecasting System

Recently, a variety of approaches have been employed to address a broad spectrum of real-world issues; these methodology cover a variety of areas, including healthcare systems. Previous researchers concentrated on health-care monitoring software. It had several shortcomings, such as poor health-care data storage, time, expense, and processing complexity. This paper proposes a unique IoT-enabled and secured clinical monitoring paradigm to address these issues. Initially, implant several sensors to gather information on vital indicators like body temperature fluctuation. Phone numbers, marital status, heart rate deviation, residence, name, age, and blood pressure are among the patient's health information. The IoT medical sensor dataset is used in this investigation. During pre-processing, extra unnecessary attributes are removed, resulting in data size reduction and normalization. A convolutional neural network supporting the classification of cancer sickness that is based on the improved teaching-learning optimization (CNN-ITLO) method. The CNN-ITLO model ascertains whether or not the patient is cancer-prone based on the sensor input. The management of the hospital receives the gathered data after which it is analyzed. Lastly, the homomorphic encryption approach is used to encrypt and store the patient's data on the cloud. The Java platform will be used to carry out the recommended work. According to the experiment results, the suggested method performed better than current cutting-edge practices.

Effects of Acute Hyperoxia on Autonomic Function and Coronary Tone in Patients with Peripheral Artery Disease.

Numerous studies have shown that oxidative stress plays an important role in peripheral artery disease (PAD). Prior reports suggested autonomic dysfunction in PAD. We hypothesized that responses of the autonomic nervous system and coronary tone would be impaired in patients with PAD during exposure to acute hyperoxia, an oxidative stressor. In 20 PAD patients and 16 healthy, sex and age-matched controls, beat-by-beat heart rate (HR, from ECG) and blood pressure (BP, with Finometer) were recorded for 10 minutes during room air breathing and 5 minutes of hyperoxia. Cardiovagal baroreflex sensitivity and HR variability (HRV) were evaluated as measures of autonomic function. Transthoracic coronary echocardiography was used to assess peak coronary blood flow velocity (CBV) in the left anterior descending coronary artery. Cardiaovagal baroreflex sensitivity at rest was lower in PAD than in healthy controls. Hyperoxia raised BP solely in the patients with PAD, with no change observed in healthy controls. Hyperoxia induced an increase in cardiac parasympathetic activity assessed by the high-frequency component of HRV in healthy controls but not in PAD. Indices of parasympathetic activity were lower in PAD than in healthy controls throughout the trial as well as during hyperoxia. Hyperoxia induced coronary vasoconstriction in both groups, while the coronary perfusion time fraction was lower in PAD than in healthy controls. These results suggest that the response in parasympathetic activity to hyperoxia (i.e., oxidative stress) is blunted and the coronary perfusion time is shorter in PAD patients.

Effects of Acupuncture on Autonomic Nervous System Parameters and Salivary Cortisol Level Among Mental Stress University Students: A Pilot Randomized Controlled Trial

Stress is a common and often unavoidable aspect of daily life that can negatively impact the autonomic nervous system, which controls the functions of internal organs and glands. Chronic stress has been associated with an imbalance in autonomic nervous system function, leading to a range of health conditions. Acupuncture is a medical treatment modality that has been applied to health care in different dimensions including physical, mental, and spiritual. This study aimed to investigate the effect of acupuncture on blood pressure, heart rate, and salivary cortisol level in mild stress university students, a population particularly vulnerable to stress. Twenty-eight university students were recruited and divided into two groups, a real acupuncture group and a sham acupuncture group. Heart rate, blood pressure, and salivary cortisol level were evaluated before and after a 30-minute acupuncture session on the ST36 acupoint. The results showed that the real acupuncture group had a significant decrease in blood pressure and heart rate, whereas the sham acupuncture group showed no change. Both groups had a slightly decrease in salivary cortisol level with no statistically significant. There was a statistically significant difference in the decrease of systolic blood pressure and heart rate after acupuncture between the two groups, but there was no significant difference between the groups in salivary cortisol level after acupuncture. The findings suggest that the acupuncture can be a valuable treatment for restoring balance to the symptoms of the autonomic nervous system in university students experiencing stress. A larger sample size, a non-intervention control, as well as different sources and times of cortisol collection, could contribute to the validation of the findings in this study.

Engagement of mental effort in response to mental fatigue: A psychophysiological analysis

Acute mental fatigue, characterized by a transient decline in cognitive efficiency during or following prolonged cognitive tasks, can be managed through adaptive effort deployment. In response to mental fatigue, individuals can employ two main behavioral patterns: engaging a compensatory effort to limit performance decrements, or disengaging effort, leading to performance deterioration. This study investigated the behavioral pattern used by participants in mental fatigue conditions. Fifty participants underwent a sequential-tasks protocol with counterbalanced sessions who took place in two separate sessions: a 30-min incongruent Stroop task (fatiguing session) or a 30-min documentary viewing task (control session), followed by a time-to-exhaustion (TTE) handgrip task at 13% of maximal voluntary contraction. Psychophysiological measures included the preejection period, heart rate variability, blood pressure, and respiration. Behavioral results showed deteriorated TTE handgrip performance after the Stroop task compared to after the documentary viewing task. During the Stroop task participants were more conservative and prioritized accuracy over speed. Self-reported fatigue was greater after the Stroop task. Psychophysiological data revealed a gradual decrease in sympathetic activity over time in both tasks, with the Stroop task showing a more pronounced decrease. Taken together, these findings suggest a disengagement of effort for a large proportion of participants (49%) that could be partly attributed to a habituation to the demands of the Stroop task. This study illustrates the interplay of behavioral patterns of effort investment in the context of mental fatigue and underscores the role of disengagement as a dominant response to this phenomenon among healthy participants.

Randomized trial of pharmacokinetic and pharmacodynamic effects of 13.2 mg intranasal epinephrine treatment in congestion

BackgroundNasal congestion could affect the absorption of an epinephrine nasal spray (ENS). ObjectiveTo compare the pharmacokinetics of 13.2 mg ENS with nasal congestion vs without congestion and vs intramuscular (IM) treatments. MethodsThis phase I, open-label, 4-period randomized crossover study enrolled 51 healthy adults with seasonal allergies into cohorts that received a single dose of 13.2 mg ENS (NDS1C; Bryn Pharma, Lebanon, New Jersey) administered as 2 consecutive sprays in either opposite nostrils (cohort 1) or the same nostril (cohort 2). Both cohorts received 13.2 mg ENS with and without nasal allergen challenge (NAC), 0.3 mg IM epinephrine by autoinjector, and 0.5 mg IM epinephrine by manual syringe (MS). ResultsThe ENS after NAC resulted in higher extent and peak exposures and more rapid time to maximum plasma concentration vs ENS without NAC and IM treatments. In cohort 1, the maximum observed baseline-adjusted epinephrine plasma concentration (pg/mL) of ENS with NAC, IM autoinjector, IM MS, or ENS without NAC was 458.0, 279.0, 364.2, and 270.1, respectively, and in cohort 2 was 436.3, 228.2, 322.3, and 250.8, respectively. The maximum observed baseline-adjusted epinephrine plasma concentration geometric mean ratio (90% CI) for ENS with NAC vs without NAC in cohort 1 was 170% (123%-234%), and in cohort 2 was 174% (115%-263%). In cohort 1, the rapid time to maximum plasma concentration was 15, 21, 45, and 25 minutes, respectively, and in cohort 2 was 18, 20, 45, and 20 minutes, respectively (P < .01 for ENS with NAC vs IM MS). The postdose mean heart rate and blood pressure remained stable and relatively similar to predose values regardless of plasma epinephrine concentration. Mild nausea and headache were the most common adverse events with ENS. ConclusionThe 13.2 mg ENS with congestion exhibited enhanced absorption vs IM treatments and ENS without congestion and seemed to be well tolerated. There was no clinically impactful relationship between pharmacodynamic effects and plasma epinephrine concentration.

Segmentation and Volumetric Analysis of Heart from Cardiac CT Images.

Cardiac CT is a valuable diagnostic tool in evaluating cardiovascular diseases. Accurate segmentation of the heart and its structures from cardiac CT and MRI images is essential for diagnosing functional abnormalities, treatment plans and cardiovascular diseases management. Accurate segmentation and quantitative assessments are still a challenge. Manual delineation of the heart from the scan images is labour-intensive, time-consuming, and error prone as it depends on the radiologist's experience. Thus, automated techniques are highly desirable as they can significantly improve the efficiency and accuracy of image analysis. This work addresses the above problems. A new, image-driven, fast, and fully automatic segmentation method was developed to segment the heart from CT images using a processing pipeline of adaptive median filter, multi-level thresholding, active contours, mathematical morphology, and the knowledge of human anatomy to delineate the regions of interest. The algorithm proposed is simple to implement and validate and requires no human intervention. The method is tested on the 'Image CHD' DICOM images (multi-centre, clinically approved single-phase de-identified images), and the results obtained were validated against the ground truths provided with the dataset. The results show an average Dice score, Jaccard score, and Hausdorff distance of 0.866, 0.776, and 33.29mm, respectively, for the segmentation of the heart's chambers, aorta, and blood vessels. The results and the ground truths were compared using Bland-Altmon plots. The heart was correctly segmented from the CT images using the proposed method. Further this segmentation technique can be used to develop AI based solutions for segmentation.

The National Sleep Research Resource: making data findable, accessible, interoperable, reusable and promoting sleep science.

This paper presents a comprehensive overview of the National Sleep Research Resource (NSRR), a National Heart Lung and Blood Institute-supported repository developed to share data from clinical studies focused on the evaluation of sleep disorders. The NSRR addresses challenges presented by the heterogeneity of sleep-related data, leveraging innovative strategies to optimize the quality and accessibility of available datasets. It provides authorized users with secure centralized access to a large quantity of sleep-related data including polysomnography, actigraphy, demographics, patient-reported outcomes, and other data. In developing the NSRR, we have implemented data processing protocols that ensure de-identification and compliance with FAIR (Findable, Accessible, Interoperable, Reusable) principles. Heterogeneity stemming from intrinsic variation in the collection, annotation, definition, and interpretation of data has proven to be one of the primary obstacles to efficient sharing of datasets. Approaches employed by the NSRR to address this heterogeneity include (1) development of standardized sleep terminologies utilizing a compositional coding scheme, (2) specification of comprehensive metadata, (3) harmonization of commonly used variables, and (3) computational tools developed to standardize signal processing. We have also leveraged external resources to engineer a domain-specific approach to data harmonization. We describe the scope of data within the NSRR, its role in promoting sleep and circadian research through data sharing, and harmonization of large datasets and analytical tools. Finally, we identify opportunities for approaches for the field of sleep medicine to further support data standardization and sharing.

Intraoperative Hypoxemia in the Right Lateral Decubitus Position: A Case Report

Platypnea-Orthodeoxia syndrome (POS), an exceptionally uncommon condition, is characterized by decreased oxygen saturation in an upright posture with corresponding improvement in the supine position. Recently, an 85-year-old female patient presented for surgery due to a left femoral neck fracture. Following successful tracheal intubation and anesthesia induction, the ventilator indicated an airway pressure of 15mmHg. While in the right lateral decubitus position, the patient developed hypoxia despite normal arterial blood pressure and symmetrical breath sounds. Attempts to alleviate the hypoxia through pure oxygen ventilation, tympanic lung ventilation, and high-frequency ventilation were unsuccessful. Subsequently, there was a notable decrease in both blood pressure and heart rate, prompting an immediate halt to the surgery and repositioning the patient to the supine position. This resulted in the normalization of the patient&amp;apos;s heart rate, oxygen saturation, and blood pressure. To investigate the etiology, a TEE probe was inserted, revealing the presence of a patent foramen ovale (PFO) and a significant right-to-left shunt while the patient was in the lateral position. The procedure was performed in a specific right lateral decubitus position. This case may represent a unique manifestation of POS syndrome, expanding the differential diagnosis for intraoperative position-related hypoxemia. Given the severe hypoxemia observed with intraoperative positional changes, a strong suspicion of POS syndrome is warranted.

Evidence that personalized racial stress procedures elicit a stress response and increases alcohol craving among Black adults with alcohol use disorder: A laboratory pilot study

BackgroundThe objective of this study was to pilot test newly developed personalized imagery procedures to investigate the impact of racial stress on alcohol craving and emotional and physiological response in Black adults with alcohol use disorder (AUD). MethodsTwenty Black adults (45% women, meanage=37.05, SDage=13.19) with AUD participated in two sessions. In the first, participants described a stressful personal event involving their race and a neutral relaxing situation and these descriptions were used to develop scripts for the subsequent laboratory exposure session. The second session was an experimental provocation session in which participants reported on alcohol craving and emotional response before and after imagined exposure to stress and neutral conditions using personalized racial stress and neutral/relaxing scripts. Conditions were randomized and counterbalanced across subjects, and heart rate and blood pressure were assessed before and after each image. ResultsAlcohol craving and negative emotions significantly increased, and positive emotions decreased following the racial stress script relative to the neutral/relaxing script. We found no differences in physiological response. Exploratory analyses found that increase in alcohol craving was correlated with racial identity exploration but not racial identity commitment, men reported greater reductions in anger than women in the neutral condition only, and income was correlated with fear in the racial stress condition only. ConclusionsThis study provides evidence that personalized racial stress procedures elicit a stress response and increases alcohol craving and emotional response but not physiological response among Black adults with AUD. These findings warrant replication in a larger study.

Revolutionizing Glucose Monitoring: Enzyme-Free 2D-MoS2 Nanostructures for Ultra-Sensitive Glucose Sensors with Real-Time Health-Monitoring Capabilities.

The growing requirement for real-time monitoring of health factors such as heart rate, temperature, and blood glucose levels has resulted in an increase in demand for electrochemical sensors. This study focuses on enzyme-free glucose sensors based on 2D-MoS2 nanostructures explored by simple hydrothermal route. The 2D-MoS2 nanostructures were characterized by powder X-ray diffraction, energy-dispersive X-ray spectroscopy, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and XPS techniques and were immobilized at GCE to obtain MoS2-GCE interface. The fabricated interface was characterized by electrochemical impedance spectroscopy which shows less charge transfer resistance and demonstrated superior electrocatalytic properties of the modified surface. The sensing interface was applied for the detection of glucose using amperometry. The MoS2-GCE-sensing interface responded effectively as a nonenzymatic glucose sensor (NEGS) over a linearity range of 0.01-0.20 μM with a very low detection limit of 22.08 ng mL-1. This study demonstrates an easy method for developing a MoS2-GCE interface, providing a potential option for the construction of flexible and disposable nonenzymatic glucose sensors (NEGS). Moreover, the fabricated MoS2-GCE electrode precisely detected glucose molecules in real blood serum and urine samples of diabetic and nondiabetic persons. These findings suggest that 2D-MoS2 nanostructured materials show considerable promise as a possible option for hyperglycemia detection and therapy. Furthermore, the development of NEGS might create new prospects in the glucometer industry.

The metabolic effects of habitual leg shaking: A randomized crossover trial.

The adverse effects of sedentary behavior on obesity and chronic diseases are well established. However, the prevalence of sedentary behavior has increased, with only a minority of individuals meeting the recommended physical activity guidelines. This study aimed to investigate whether habitual leg shaking, a behavior traditionally considered unfavorable, could serve as an effective strategy to improve energy metabolism. A randomized crossover study was conducted, involving 15 participants (mean [SD] age, 25.4 [3.6]; mean [SD] body mass index, 22 [3]; 7 women [46.7%]). The study design involved a randomized sequence of sitting and leg shaking conditions, with each condition lasting for 20 min. Energy expenditure, respiratory rate, oxygen saturation, and other relevant variables were measured during each condition. Compared to sitting, leg shaking significantly increased total energy expenditure [1.088 kj/min, 95% confidence interval, 0.69-1.487 kj/min], primarily through elevated carbohydrate oxidation. The average metabolic equivalent during leg shaking exhibited a significant increase from 1.5 to 1.8. Leg shaking also raised respiratory rate, minute ventilation, and blood oxygen saturation levels, while having no obvious impact on heart rate or blood pressure. Electromyography data confirmed predominant activation of lower leg muscles and without increased muscle fatigue. Intriguingly, a significant correlation was observed between the increased energy expenditure and both the frequency of leg shaking and the muscle mass of the legs. Our study provides evidence that habitual leg shaking can boost overall energy expenditure by approximately 16.3%. This simple and feasible approach offers a convenient way to enhance physical activity levels.

The Effect of Different Motocross Circuit Typologies on Internal Load and External Load Responses in Riders

Background: Several physical and physiological changes occur during a motocross race, mainly due to the type of circuits, and therefore the impact of different types of circuits on training load responses continues to need to be fully clarified. Objective: The main aim of the present study was to compare the internal load and external load responses of motocross riders from different classes and on circuits of different types. Method: A quasi experimental design research was used in the study.The sample consisted of 10 motocross riders (28.10 ± 7.53 years; 74.60 ± 9.70 kg; 176.50 ± 7.18 cm; 23.88 ± 2.18 BMI), male., distributed by the Mx Elite and Mx Hobby categories. The pilots were evaluated before and after the race in relation to indicators of external load (accelerations and decelerations, maximum speed and average speed and impacts) and internal load (Heart rate, blood lactate and rating of perceived exertion) on two circuits of different types. Results: There was a trend towards higher internal load responses in the Mx Hobby class compared to the Mx Elite class (p ≤ 0.05), regardless of the circuit. Regarding external load responses, the Mx Hobby class has a tendency towards higher maximum and average speeds, while the Mx Elite class presents the same tendency for accelerations and decelerations. Conclusions: Different circuit types appear to influence pilots’ internal load and external load responses.

Investigating the Effects of Ultraendurance Running on Athletes' Heart Rate and Blood Pressure

Investigating the Effects of Ultraendurance Running on Athletes' Heart Rate and Blood Pressure

The Effect of Acute Ketone Supplementation on Time to Fatigue in NCAA Division I Cross-Country Athletes

This study investigated the effect of a commercially available ketone supplement on heart rate (HR), perceived exertion (RPE), blood lactate, glucose, and ketone concentrations, along with time to fatigue (TTF) during a running task to voluntary fatigue. Twelve NCAA Division I cross-country athletes took part in this randomized, double-blind, placebo-controlled cross-over study. Bayesian methodologies were employed for all statistical analyses, and point estimates were determined to be statistically significant if the 95% highest-density intervals (HDI) excluded zero. TTF was not significantly different between conditions with a Meandiff = 48.7 ± 6.3 s (95% HDI: −335, 424) and a 0.39 probability derived from the posterior distribution, indicating the likelihood that the supplement would increase TTF compared to the placebo control. Lactate concentrations immediately post-exercise were significantly lower in the supplement trial relative to placebo with an estimated Meandiff = −4.6 ± 1.9 mmol; 95% HDI: −8.3, −0.9. There were no significant interaction effects observed for either blood glucose or ketone concentrations nor HR or RPE. These findings imply that the acute ingestion of ketones before running at lactate threshold pace has a low probability of increasing TTF in highly trained Division I runners.

Effects of mild hyperbaric oxygen therapy on timing sequence recovery of muscle fatigue in chinese university male athletes

ObjectivesThis study aimed to investigate the timing sequence recovery effects of single and repeated Mild Hyperbaric Oxygen Therapy (MHOT) on muscle fatigue induced by cycling exercise through a comprehensive set of parameters. MethodsThis study employed a controlled crossover design involving 12 Chinese secondary national-level male athletes. Each participant completed two identical trials over six days. Each trial consisted of a 90-min cycling exercise followed by either a Control (CON) intervention (1 atm absolute (ATA), 20.9 % oxygen, 60 min) or MHOT intervention (1.25 ATA, 26%–28 % oxygen, 60 min). Various physiological parameters including Rating of Perceived Exertion (RPE), Heart Rate (HR), Peripheral Oxygen Saturation (SpO2), Perfusion Index (PI%), Creatine Kinase (CK), Lactate Dehydrogenase (LDH), Lactic Acid (LA), Blood Urea Nitrogen (BUN), Superoxide Dismutase (SOD), Malondialdehyde (MDA), and Standing Long Jump Distance (SLJ) were measured at six different time points throughout the trials. ResultsRPE revealed that the MHOT group experienced reduced subjective fatigue in comparison to the CON group (P < 0.05). Additionally, MHOT demonstrated quicker recovery in HR and PI% compared to the CON group (P < 0.05). Regarding CK, LA, BUN, SOD, and MDA levels, the MHOT group exhibited accelerated recovery post-6 intervention and at the 24-h mark after six interventions, showing significant improvement over the CON group (P < 0.05). However, no notable disparity was observed between groups concerning SpO2, LDH, and SLJ. ConclusionsBoth single and repeated sessions of MHOT demonstrated efficacy in alleviating subjective fatigue and promoting recovery of heart rate and blood perfusion following muscle fatigue, ensuring parallel structure and consistency in their effects. Repeated MHOT sessions (six times) exhibit a significant reduction in levels of blood markers associated with muscle damage, metabolites, and oxidative stress. However, the impact of a single MHOT intervention was less pronounced.