Effects of occlusion pressure on hemodynamic responses recorded by near-infrared spectroscopy across two visits.

Ischemic Preconditioning (IPC) has emerged as a promising approach to mitigate the impact of hypoxia on physiological functions. However, the heterogeneity of occlusion pressures for inducing arterial occlusion has led to inconsistent hemodynamic outcomes across studies. This study aims to evaluate the peripheral hemodynamic responses to partial and total blood-flow occlusions on the left arm at rest, using absolute or individualized pressures, on two occasions.

Effects of Yoga and Mindfulness Meditation on Stress-Related Variables: A Randomized Controlled Trial.

Stressful situations lead to change in or damage to the central nervous system, the hypothalamic-pituitary-adrenal axis, and autonomic function. Techniques for reducing stress such as yoga and mindfulness meditation have been reported to improve emotional regulation and mindfulness skill, as well as stress response. Mindfulness skill relies on intense focus to quiet the mind and bring concentration to the present moment.

Accuracy and reliability of the optoelectronic plethysmography and the heart rate systems for measuring breathing rates compared with the spirometer.

Measuring breathing rates without a mouthpiece is of interest in clinical settings. Electrocardiogram devices and, more recently, optoelectronic plethysmography (OEP) methods can estimate breathing rates with only a few electrodes or motion-capture markers placed on the patient. This study estimated and compared the accuracy and reliability of three non-invasive devices: an OEP system with 12 markers, an electrocardiogram device and the conventional spirometer.

Artificial Intelligence for Cardiac Diseases Diagnosis and Prediction Using ECG Images on Embedded Systems.

The electrocardiogram (ECG) provides essential information about various human cardiac conditions. Several studies have investigated this topic in order to detect cardiac abnormalities for prevention purposes. Nowadays, there is an expansion of new smart signal processing methods, such as machine learning and its sub-branches, such as deep learning.

Intra- and Inter-Day Reliability of the NIRS Portamon Device after Three Induced Muscle Ischemias.

(1) Background: Near-infrared spectroscopy (NIRS) is an innovative and non-invasive technology used to investigate muscular oxygenation. The aim of this study is to assess the within- and between-session reliability of the NIRS Portamon (Artinis, Elst, Netherlands) device following three sets of induced muscle ischemia. (2) Methods: Depending on the experimental group (G1, G2 or G3), a cuff was inflated three times on the left upper arm to 50 mmHg (G1), systolic blood pressure (SBP) + 50 mmHg (G2) or 250 mmHg (G3).

The effect of a single spinal manipulation on cardiovascular autonomic activity and the relationship to pressure pain threshold: a randomized, cross-over, sham-controlled trial.

Background: The autonomic nervous system interacts with the pain system. Knowledge on the effects of high velocity low amplitude spinal manipulations (SM) on autonomic activity and experimentally induced pain is limited. In particular, the effects of SM on autonomic activity and pain beyond the immediate post intervention period as well as the relationship between these two outcomes are understudied.

Effect of the Anode Placement on the Antagonist Muscles Recruitment: Implication for the Interpolated Twitch Technique Outcome.

The aim of the present study was to compare the recruitment of the antagonist muscles and its effect on the measurement of the voluntary activation level (VA) of the knee extensor (KE) muscles for different anode placements used to stimulate the femoral nerve. We hypothesized that when the anode is positioned over the gluteal fold (GF), the antagonist muscles recruitment would be greater and, thus the VA overestimated, than when the anode is placed midway between the greater trochanter and the lower border of the iliac crest (Mid). Thirteen healthy men (23 ± 4 yr) were tested in both conditions (GF vs.

New physiological bench test reproducing nocturnal breathing pattern of patients with sleep disordered breathing.

Previous studies have shown that Automatic Positive Airway Pressure devices display different behaviors when connected to a bench using theoretical respiratory cycle scripts. However, these scripts are limited and do not simulate physiological behavior during the night. Our aim was to develop a physiological bench that is able to simulate patient breathing airflow by integrating polygraph data.

Effects of Age, Exercise Duration, and Test Conditions on Heart Rate Variability in Young Endurance Horses.

Although cardiac recovery is an important criterion for ranking horses in endurance competitions, heart rate variability (HRV) has hardly ever been studied in the context of this equestrian discipline. In the present study, we sought to determine whether HRV is affected by parameters such as age, exercise duration and test site. Accordingly, HRV might be used to select endurance horses with the fastest cardiac recovery.

Effect of oral glucocorticoid intake on autonomic cardiovascular control.

This study analyzed baroreflex sensitivity, heart rate and systolic blood pressure variabilities during an oral 1 week administration of prednisone. This study examined the hypothesis that prednisone might change both systolic blood pressure level and baroreflex sensitivity. Twelve physically active male subjects participated to a double-blind, randomized cross-over study consisting of two 1-week periods of treatment separated by a 4-week drug-free washout period: placebo (PLA) or prednisone (PRED).

Speed and Cardiac Recovery Variables Predict the Probability of Elimination in Equine Endurance Events.

Nearly 50% of the horses participating in endurance events are eliminated at a veterinary examination (a vet gate). Detecting unfit horses before a health problem occurs and treatment is required is a challenge for veterinarians but is essential for improving equine welfare. We hypothesized that it would be possible to detect unfit horses earlier in the event by measuring heart rate recovery variables.

Effect of "Touch Rugby" Training on the Cardiovascular Autonomic Control In Sedentary Subjects.

This study aimed to explore the effects of "touch-rugby" training on the cardiovascular autonomic control in sedentary subjects. 22 adults (30-64 years old) were included in this study. Before (pre-test) and after (post-test) the period of training, cardio-respiratory recordings were achieved at rest and during a graded maximal exercise on a treadmill.

Improved tolerance of peripheral fatigue by the central nervous system after endurance training.

Purpose: The purposes of this study were to evaluate the effect of endurance training on central fatigue development and recovery.

Methods: A control group was compared to a training group, which followed an 8-week endurance-training program, consisting in low-force concentric and isometric contractions. Before (PRE) and after (POST) the training period, neuromuscular function of the knee extensor (KE) muscles was evaluated before, immediately after and during 33 min after an exhausting submaximal isometric task at 15 % of the maximal voluntary contraction (MVC) force.

Time-course of prednisone effects on hormonal and inflammatory responses at rest and during resistance exercise.

Glucocorticoids are among the most commonly used drugs. They are widely administered for acute and chronic musculoskeletal pain, as well as for several other pain syndromes, although their therapeutic use is sometimes diverted for doping purposes. Their time-course effects on hormonal and inflammatory responses nevertheless remain poorly understood, both at rest and during exercise.

Ergogenic and metabolic effects of oral glucocorticoid intake during repeated bouts of high-intensity exercise.

All systemically administered glucocorticoids (GC) are prohibited in-competition, because of the potential ergogenic effects. Although short-term GC intake has been shown to improve performance during submaximal exercise, literature on its impact during brief intense exercise appears to be very scant. The purpose of this study was to examine the ergogenic and metabolic effects of prednisone during repeated bouts of high-intensity exercise.

Effects of endurance training on the maximal voluntary activation level of the knee extensor muscles.

Purpose: The aim of this study was to investigate the neural adaptations to endurance training, and more specifically the adaptation of the cortical voluntary activation of the knee extensor (KE) muscles.

Methods: Sixteen sedentary men were randomly allocated into an endurance training (n = 8) or a control group (n = 8). All subjects performed a maximal aerobic speed test (MAS) before and immediately after the training period.

Therapeutic glucocorticoid administration alters the diurnal pattern of dehydroepiandrosterone.

Significant alteration in hypothalamic-pituitary-adrenal function has been demonstrated in patients after short-term glucocorticoid therapy, but its impact on the circadian rhythm of steroid hormones has never been investigated. This study examined the effects of short-term prednisone administration on the diurnal patterns of dehydroepiandrosterone (DHEA) and testosterone. Saliva samples were collected from 11 healthy, physically active, male volunteers for DHEA and testosterone analysis, as follows: every 4 h from 0800 to 2000 h on 2 control days without medication, and after 1 week of oral therapeutic prednisone treatment (60 mg daily) (days 0-3).

GC-MS analysis of cuticular lipids in recent and older scavenger insect puparia. An approach to estimate the postmortem interval (PMI).

An analytical method was developed to characterize puparia cuticular lipids (hydrocarbons, waxes) and to compare the molecular distribution patterns in the extracts from either recent or older puparia. Acid-catalyzed transesterification and solvent extraction and purification, followed by combined gas chromatography coupled to mass spectrometry, were optimized for the determination of hydrocarbons and fatty acid ethyl esters from transesterified waxes, extracted from a single species of a fly scavenger (Hydrotaea aenescens Wiedemann, 1830). Comparison between recent (2012) or older (1997) puparia contents has highlighted significant composition differences, in particular, a general decrease of the chain length in the n-alkane distribution pattern and, on the contrary, an increase of the ester chain length.

Effect of playing surface properties on neuromuscular fatigue in tennis.

Purpose: The aim of this study was to evaluate the effect of the playing surface properties on the development of neuromuscular fatigue in tennis.

Methods: Ten subjects played randomly two tennis matches on hard court (HARD) and clay court (CLAY) for an effective playing duration of 45 min (i.e.

Oxygen consumption and gait variables of Arabian endurance horses measured during a field exercise test.

Reasons For Performing Study: Arabian horses have morphological, muscular and metabolic features designed for endurance races. Their gas exchange and gait variables were therefore measured during a field exercise test. This study presents original respiratory and locomotor data recorded in endurance horses under field conditions.

Validation of a semi-classical signal analysis method for stroke volume variation assessment: a comparison with the PiCCO technique.

This study proposes a Semi-Classical Signal Analysis (SCSA) method for stroke volume (SV) variations assessment from arterial blood pressure measurements. One of the SCSA parameters, the first systolic invariant (INVS₁), has been shown to be linearly related to SV. To technically validate this approach, the comparison between INVS₁ and SV measured with the currently used PiCCO technique was performed during a 15-min recording in 20 mechanically ventilated patients in intensive care.

Relationship between ventilatory thresholds and systolic blood pressure variability.

During exercise, an increase in respiratory rate amplifies the blood pressure oscillations. This phenomenon is usually intensified when exercise rate exceeds the ventilatory thresholds (VTs). The present study examined whether VTs assessment was possible from systolic blood pressure variability (SBPV) analysis to give blood pressure ventilatory thresholds (BPVTs).

Role of brainstem centers in cardiorespiratory phase difference during mechanical ventilation.

During mechanical ventilation, large inter-patient and intra-patient variations of the phase of respiratory sinus arrhythmia (RSA) were described. To determine whether these variations were neurally mediated, we compared the RSA phase between: (1) 12 control subjects, (2) 23 mechanically ventilated patients without brain injury (MV group) and (3) 12 brain dead, mechanically ventilated patients, whose central nervous functions were abolished (BD group). ECG and ventilatory flow were recorded during 15 min and the RSA phase was then continuously computed by complex demodulation.