near infrared spectroscopy muscle oxygen

SIGNIFICANCE: Non-invasive optical measurements of deep tissue (e.g., muscle) need to take into account confounding contributions from baseline and dynamic optical properties of superficial tissue (adipose tissue). AIM: Discriminate superficial and deep tissue hemodynamics using data collected with frequency-domain (FD) near-infrared spectroscopy (NIRS) in a dual-slope (DS) configuration. APPROACH: Experimental data were collected in vivo on the forearm of three human subjects during a 3-min arterial occlusion or 1-min venous occlusion...

BACKGROUND: Few studies have examined changes in skeletal muscle physiology post-stroke. This study examined changes in tissue oxygen saturation (StO2 ) of the vastus lateralis (VL) muscle of stroke survivors and age-matched control participants during maximal and submaximal isometric contractions of the knee extensor muscles. OBJECTIVES: We hypothesized that tissue oxygen desaturation (ΔStO2 ) during knee extensor muscle contractions would be less in the VL in the paretic vs...

BACKGROUND AND OBJECTIVES: Limb ischemia or compartment syndrome, requiring surgery, are some of the frequent cannula-related complications in patients supported with veno-arterial extracorporeal membrane oxygenation (VA-ECMO). The purpose of this exploratory study is to depict and evaluate the dynamic changes in the lower limb muscles with ultrasound shear wave elastography as marker for early lower limb ischemia. METHODS: Eleven patients with VA-ECMO after cardiac arrest were included in this study...

SIGNIFICANCE: Mechanical ventilation (MV) is a cornerstone technology in the intensive care unit as it assists with the delivery of oxygen in critical ill patients. The process of weaning patients from MV can be long, and arduous and can lead to serious complications for many patients. Despite the known importance of inspiratory muscle function in the success of weaning, current clinical standards do not include direct monitoring of these muscles. AIM: The goal of this project was to develop and validate a combined frequency domain near infrared spectroscopy (FD-NIRS) and diffuse correlation spectroscopy (DCS) system for the noninvasive characterization of inspiratory muscle response to a load...

Objective. 
In this paper, we present a detailed in vivo characterization of the optical and hemodynamic properties of the human sternocleidomastoid muscle (SCM), obtained through ultrasound-guided near-infrared time-domain and diffuse correlation spectroscopies.
 Approach. 
A total of sixty-five subjects (forty-nine females, sixteen males) among healthy volunteers and thyroid nodule patients have been recruited for the study. Their SCM hemodynamic (oxy-, deoxy- and total hemoglobin concentrations, blood flow, blood oxygen saturation and metabolic rate of oxygen extraction) and optical properties (wavelength dependent absorption and reduced scattering coefficients) have been measured by the use of a novel hybrid device combining in a single unit time-domain near-infrared spectroscopy, diffuse correlation spectroscopy and simultaneous ultrasound imaging...

BACKGROUND: Repetitive piano movements have been associated with playing-related musculoskeletal disorders (PRMDs) such as forearm myalgia and symptoms of lateral epicondylopathy. Despite the high prevalence of PRMDs among pianists, there is poor understanding regarding the underlying physiological mechanisms. Intramuscular oxygenation may play a role in the development of PRMDs. Therefore, this observational study aimed to explore the effect variability of playing piano repertoire on the oxygenation of the extensor carpi radialis brevis (ECRB)...

BACKGROUND: Peripheral muscle fractional tissue oxygen extraction (pFTOE) represents the relative extraction of oxygen from the arterial to venous compartment, providing information about dynamic changes of oxygen delivery and oxygen consumption. The aim of the present study was to establish reference values of pFTOE during the first 24 h after birth in stable term and late preterm neonates. METHODS: The present study is a post-hoc analysis of secondary outcome parameters of prospective observational studies...

This study aimed to assess the reliability and validity of estimating the respiratory compensation point (RCP) in trained endurance athletes by analyzing intercostal muscles' NIRS-derived tissue oxygenation dynamics. Seventeen experienced trail runners underwent an incremental treadmill protocol on two separate occasions, with a 7-day gap between assessments. Gas exchange and muscle oxygenation data were collected, and the oxygen saturation breakpoint (SmO2 BP) measured in the intercostal muscles was compared to the RCP, which was identified by the increase in the VE/V...

Exercise increases the cost of breathing (COB) due to increased lung ventilation (V˙E), inducing respiratory muscles deoxygenation (∇SmO2 ), while the increase in workload implies ∇SmO2 in locomotor muscles. This phenomenon has been proposed as a leading cause of exercise intolerance, especially in clinical contexts. The use of high-flow nasal cannula (HFNC) during exercise routines in rehabilitation programs has gained significant interest because it is proposed as a therapeutic intervention for reducing symptoms associated with exercise intolerance, such as fatigue and dyspnea, assuming that HFNC could reduce exercise-induced ∇SmO2 ...

It remains unclear whether accurate motor performance and cortical activation differ among grasping forms across several force levels. In the present study, a ballistic target force matching task (20%, 40%, 60%, and 80% of maximum voluntary force) with power grip, side pinch, and pulp pinch was utilized to explore the accuracy of the forces generated as well as the muscular activity of intrinsic and extrinsic hand muscles. By using near-infrared spectroscopy, we also examined bilateral dorsolateral prefrontal cortex (DLPFC) activation during the preparatory phase (initial 10 s) of the task...

This study aimed to associate body composition with fractional oxygen extraction at rest in healthy adult men. Fourteen healthy adults (26.93 ± 2.49 years) from Chile participated. Body composition was assessed with octopole bioimpedance, and resting muscle oxygenation was evaluated in the vastus lateralis quadriceps with near-infrared spectroscopy (NIRS) during a vascular occlusion test, analyzing the muscleVO2 , resaturation velocity during reactive hyperemia via the muscle saturation index (%TSI), and the area above the curve of HHb (AACrep)...

PURPOSE: Autonomic control of orofacial areas is an integral part of the stress response, controlling functions such as pupil dilatation, salivation, and skin blood flow. However, the specific control of blood flow in head muscles during stress is unknown. This study aims to investigate the hemodynamic response of temporalis and masseter muscles in response to five different stressors. METHODS: Sixteen healthy individuals were subjected to a randomized series of stressors, including cold pressor test, mental arithmetic test, apnea, isometric handgrip, and post-handgrip muscle ischemia, while in the sitting posture...

PURPOSE: To compare deoxygenation of the sternocleidomastoid, scalenes, and diaphragm/intercostals (Dia/IC) during submaximal intermittent neck flexion (INF) versus submaximal inspiratory threshold loading (ITL) in healthy adults. METHODS: Fourteen participants performed a randomized, cross-over, repeated measures design. After evaluation of maximal inspiratory pressures (MIP) and maximum voluntary contraction (MVC) for isometric neck flexion, participants were randomly assigned to submaximal ITL or INF until task failure...

BACKGROUND: The local hemodynamic response after cupping therapy has been considered as a contributing factor for improving muscle tissue health; however, the effects of cupping pressure and duration on the spatial hemodynamic response have not been investigated. OBJECTIVE: The objective of this study was to investigate the hemodynamic response inside and outside the cupping cup under various pressures and durations of cupping therapy. METHODS: A 3-way factorial design with repeated measures was used to investigate the main and interaction effects of the location (areas inside and outside the cup), pressure (-225 and -300 mmHg) and duration (5 and 10 min) on the hemodynamic response of the biceps muscle...

OBJECTIVE: Previous research has primarily focused on the association between muscle strength and global cognitive function in older adults, while the connection between muscle strength and advanced cognitive function such as inhibition and working memory (WM) remains unclear. This study aimed to investigate the relationship among muscle strength, WM, and task-related cortex hemodynamics. METHODS: We recruited eighty-one older adults. Muscle strength was measured using a grip and lower limb strength protocol...

BACKGROUND: Unilateral diaphragm dysfunction (UDD) is an underdiagnosed cause of dyspnoea. Inspiratory muscle training (IMT) is the only conservative treatment for UDD, but the mechanisms of improvement are unknown. We characterised the effects of IMT on dyspnoea, exercise tolerance and respiratory muscle function in people with UDD. METHODS: 15 people with UDD (73% male, 61±8 years) were randomised to 6 months of IMT (50% maximal inspiratory mouth pressure ( P I,max ), n=10) or sham training (10% P I,max , n=5) (30 breaths twice per day)...

We investigated the relationship of the time-dependent behaviour of muscle oxygen saturation SmO2 (t), phosphagen energy supply WPCr (t) and blood lactate accumulation ΔBLC(t) during a 60-s all-out cycling sprint and tested SmO2 (t) for correlations with the end of the fatigue-free state tFf , maximal pedalling rate PRmax and maximal blood lactate accumulation rate v̇Lamax . Nine male elite track cyclists performed four maximal sprints (3, 8, 12, 60 s) on a cycle ergometer. Crank force and cadence were monitored continuously to determine PRmax and tFf based on force-velocity profiles...

We developed a multidistance and multiwavelength continuous wave NIRS instrument to detect dynamic changes in oxygenated and deoxygenated hemoglobin (oxy- and deoxy-Hb), oxidized cytochrome-c-oxidase (oxCCO) and water of the brain and muscle. We performed measurements of the forehead during resting state and paced breathing and of the forearm during ischemic challenge in human adults. Time series analysis focusing on rhythmic signals over different time scales and different depths of the tissue revealed specific patterns of phase relationships among the signals in each of the measurement...

The aim of this study was to investigate the longitudinal relationship between the slopes of systemic and quadriceps muscle O2 dynamics in subjects without attenuation point in deoxygenated hemoglobin concentration at vastus lateralis (APdeoxy-Hb@VL ) during high-intensity cycling. Seven young men without APdeoxy-Hb@VL performed ramp cycling exercise until exhaustion before and after 8 weeks, while continuing recreational physical activities throughout that period. Muscle O2 saturation (SmO2 ) and deoxy-Hb were monitored at the vastus lateralis (VL) and rectus femoris (RF) by near infrared spectroscopy oximetry during exercise...

Long periods of bed rest for elderly population, due to a femur fracture event, can cause a deterioration in the muscular capacity. Therefore, monitoring of the muscle oxidative capacity in this fragile population is necessary to define the muscular oxidative metabolism state before and after a rehabilitation period. The time-domain near-infrared spectroscopy (TD-NIRS) technique enables the absolute values to be calculated for hemodynamic parameters such as oxy- (O2 Hb), deoxy- (HHb), total- (tHb) haemoglobin, and tissue oxygen saturation (SO2 ) of the muscular tissue...