Publications using the PortaLite
Oxygenation time course and neuromuscular fatigue during repeated cycling sprints with bilateral blood flow restriction
The aim was to evaluate changes in peripheral and cerebral oxygenation, cardiorespiratory, and performance differences, as well as neuromuscular fatigue across multiple levels of blood flow restriction (BFR) during a repeated cycling sprint test to …
One-week cocoa flavanol intake increases prefrontal cortex oxygenation at rest and during moderate-intensity exercise in normoxia and hypoxia
During exercise in hypoxia, O2 delivery to brain and muscle is compromised, and oxidative stress is elicited. Cocoa flavanols (CF) have antioxidant capacities and can increase blood flow by stimulating endothelial function. We aimed to examine the …
NIRS-based experimental evaluation of driver back fatigue during long-term driving
Most research on the relationship between driver fatigue, driving comfort, stability and other factors related to driving has consisted subjective assessments via surveys. Bio-signal measurements allow more objective evaluations but the measurement …
Optimization measurement of muscle oxygen saturation under isometric studies using FNIRS
Development of functional near infrared spectroscopy (fNIRS) technologies has advanced quantification signal using multiple wavelength and detector to investigate hemodynamic response in human muscle. These non-invasive technologies have been widely …
Assessing prefrontal cortex oxygenation after sport concussion with near-infrared spectroscopy
Background: Clinicians typically rely on neuropsychological and balance tests to track concussion recovery. The aforementioned tests imply impairments that are based on performance, but these tests do not directly measure brain physiology throughout …
Effects of trying ‘not to move' instruction on cortical load and concurrent cognitive performance
Motor and cognitive tasks often interfere when performed concurrently. The amount of interference typically scales with difficulty of the tasks involved. Thus, supposedly ‘easy' motor tasks with restricted movement amplitude, like sitting on a chair, …
Neurovascular coupling during cognitive activity in adults with controlled hypertension
Hypertension even when controlled, may accelerate arterial stiffening and impair the ability of the cerebrovasculature to increase blood flow to support neural activity, i.e., neurovascular coupling (NVC). Optimal NVC depends on continuous, …
Prefrontal cortex oxygenation evoked by convergence load under conflicting stimulus-to-accommodation and stimulus-to-vergence eye-movements measured by NIRS
Purpose: To extend our knowledge of the functional linkages between visual fatigue and regional cerebral prefrontal cortex (PFC) oxygenation, we measured time related hemodynamic changes over the right dorsolateral prefrontal cortex (dlPFC) during …
Reliability of muscle blood flow and oxygen consumption response from exercise using near-infrared spectroscopy
New Findings: What is the central question of this study? Continuous-wave near-infrared spectroscopy, coupled with venous and arterial occlusions, offers an economical, non-invasive alternative to measuring skeletal muscle blood flow and oxygen …
Treadmill walking reduces pre-frontal activation in patients with Parkinson's disease
Background: Among patients with Parkinson's disease (PD), gait is typically disturbed and less automatic. These gait changes are associated with impaired rhythmicity and increased prefrontal activation, presumably in an attempt to compensate for …
Influence of exercise duration on cardiorespiratory responses, energy cost and tissue oxygenation within a 6 hour treadmill run
Purpose. The physiological mechanisms for alterations in oxygen utilization (V˙O2) and the energy cost of running (Cr) during prolonged running are not completely understood, and could be linked with alterations in muscle and cerebral tissue …
When is Higher Level Cognitive Control Needed for Locomotor Tasks Among Patients with Parkinson's Disease?
Turning has been implicated as a complex task that requires both motor and cognitive resources. Accumulating evidence shows that patients with Parkinson's disease (PD) require more steps and more time to complete a turn, however, the role of the …
Prediction of oxygen uptake dynamics by machine learning analysis of wearable sensors during activities of daily living
Currently, oxygen uptake (VO2) is the most precise means of investigating aerobic fitness and level of physical activity; however, VO2 can only be directly measured in supervised conditions. With the advancement of new wearable sensor technologies …
Oxygenation dynamics of sepsis patients undergoing far-infrared intervention based on near-infrared spectroscopy
Near-infrared spectroscopy (NIRS; continuous wave type) is a noninvasive tool for detecting the relative change of oxyhemoglobin and deoxyhemoglobin. To make this change, intervention methods must be applied. This study determined the hemodynamics of …
Effects of aging on prefrontal brain activation during challenging walking conditions
Background Deficits in cognitive domains, in particular, those related to the prefrontal cortex, contribute to diminished walking performance in complex conditions in older age. Studies using functional near infra-red spectroscopy (fNIRS) reported …
Possible Influence of Perturbation Implication, a Neurorehabilitation Model, On Brain Plasticity Using NIRS System
Improvements in the treatment of stroke lead to an increase in the number of patients living with the consequences of stroke. Although stroke induces cognitive impairment, a lack in mobility or difficulties in walking are common problems for stroke …
Sex differences in the oxygen delivery, extraction, and uptake during moderate-walking exercise transition
Previous studies in children and older adults demonstrated faster oxygen uptake (VO2) kinetics in males compared with females, but young healthy adults have not been studied. We hypothesized that young men would have faster aerobic system dynamics in …
Measuring prefrontal cortical activity during dual task walking in patients with Parkinson's disease: Feasibility of using a new portable fNIRS device
Background: Many patients with Parkinson's disease (PD) have difficulties in performing a second task during walking (i.e., dual task walking). Functional near-infrared spectroscopy (fNIRS) is a promising approach to study the presumed contribution …
Effect of hypoxia on cerebrovascular and cognitive function during moderate intensity exercise
Exercise in hypoxia places added demands on the brain and cerebrovasculature that can impact cognitive function. The purpose of this study was to investigate the effect of acute hypoxia on cerebrovascular hemodynamics, markers of neuro-steroidal …
Forearm muscle oxidative capacity index predicts sport rock-climbing performance
Abstract: Rock-climbing performance is largely dependent on the endurance of the forearm flexors. Recently, it was reported that forearm flexor endurance in elite climbers is independent of the ability to regulate conduit artery (brachial) blood …