PURPOSE: Previous studies have used near-infrared spectroscopy (NIRS) to measure skeletal muscle mitochondrial capacity. This study tested the hypothesis that NIRS-measured mitochondrial capacity would improve with endurance exercise training and …
Purpose: Previous work identified an asymmetry in tissue desaturation changes in the left and right quadriceps muscles during on-ice skating at maximal speed in males. The effect of changing race distance on the magnitude of desaturation or leg …
Wearable, wireless near-infrared (NIR) spectrometers were used to compare changes in on-ice short-track skating race simulations over 1,500 m with a 3-min cycle ergometry test at constant power output (400 W). The subjects were six male elite …
Near-infrared spectroscopy (NIRS) is a non-invasive optical imaging technique, which is increasingly used to measure hemodynamic responses in the motor cortex. The location at which the NIRS optodes are placed on the skull is a major factor in …
Caffeine has been shown to modulate cerebral blood flow, with little evidence of tolerance to these effects following habitual use. However, previous studies have focused on caffeine levels much higher than those found in dietary servings and have …
The purpose of the study was to investigate the effect of 30-min voluntary hyperpnoea on cerebral, respiratory and leg muscle balance between O2 delivery and utilization during a subsequent constant-power test. Eight males performed a V̇O2max test, …
This study investigated the pattern of changes in muscle oxygenation, deoxygenation and blood volume in the sternocleidomastoid (SCM) in comparison with the parasternal (PS) and intercostal (IC) muscles during a bout of incremental inspiratory …
The study examined the influence of cerebral (prefrontal cortex) and muscle (vastus lateralis) oxygenation on the ability to perform repeated, cycling sprints. Thirteen team-sport athletes performed ten, 10-s sprints (with 30 s of rest) under …
To study elbow muscle load sharing we investigated the effect of external flexion-extension (FE) and pronation-supination (PS) moments and elbow angle on muscle activation and oxygen consumption (V̇O2).Two data sets were obtained. First, (n=6) …
Fatigability and muscle oxygen consumption (mVO2) during sustained voluntary isometric knee extensions are less at extended (30° knee angle; 07deg;, full extension) versus flexed knee angles (907deg;). This lower energy consumption may partially …
Sufficient O2-supply to the brain is necessary for an adequate cerebral energy metabolism, function and growth. To elucidate the relation between changes in, respectively, mean arterial blood pressure (MABP) and cerebral O2-supply and changes in the …
Inverse-dynamic models often use cost functions to solve the load-sharing problem. Although it is often assumed that energy is minimised, most cost functions are based on mechanically related measures like muscle force or stress. The aim of this …
Local oxygen consumption in a muscle (V̇O2) can be determined by near infrared spectroscopy (NIRS). In principle it should be possible to use this measure to validate musculoskeletal models. However, the relationship between V̇O2 and external force, …
The aim of this study was to investigate the performance of in vivo quantitative near-infrared spectroscopy (NIRS) in skeletal muscle at various workloads. NIRS was used for the quantitative measurement of O2 consumption (mVO2) in the human flexor …
Interrogation of tissue with light offers the potential for noninvasive chemical measurement, and penetration with near-infrared wavelengths (750-1000 nm) is greater than with visible light. Specific absorption by clinically relevant compounds such …
Conventional near infrared spectroscopy (NIRS), introduced by Jobsis in 1977, can be considered as a reliable trend monitor for cerebral oxygenation. Quantisation, however, is complex and cumbersome. Recently a relatively simple system for cerebral …
The aim of this study was to determine oxygen consumption (VO2) during isometric exercise in human muscles using near infrared spectroscopy (NIRS). The technique was used to study the relationship between VO2 in the soleus muscle and the level of …
A short history of oximetry During the second half of the 19th century it was discovered that blood cells contain a colouring substance whose spectrum is influenced by various blood gases [Hoppe, 1862]. Stokes discovered that this coloured substance …