PortaMon
The gold-standard research device for the measurement of muscle oxygenation
Publications using the PortaMon
Effects of 6-day ischaemic preconditioning on adaptations to an altitude training camp in cross-country skiers
To determine whether ischaemic preconditioning (IPC) administered prior to an altitude training camp could enhance aerobic fitness and endurance performance in athletes. In a randomized controlled trial, 19 competitive (Tiers 3–5) cross-country (XC) …
Exercise Intensity but Not Cadence Affects the Dynamics of Muscle Oxygenation and Pulmonary Oxygen Uptake at the Onset of Exercise in Trained Cyclists
Purpose: This study examined how exercise intensity and pedaling cadence influence the on-transient kinetics of pulmonary oxygen uptake ( V˙O2) and muscle oxygenation in trained cyclists. Specifically, we evaluated responses during transitions to …
Inter-effort hypoxia recovery during high-intensity intermittent exercise enhances oxygen uptake at the onset of efforts while maintaining exercise tolerance
Exercise training in hypoxia enhances physiological adaptations improving exercise performance. However, acute hypoxia generally reduces high-intensity exercise tolerance, limiting its application in sports training. Here, we investigated whether …
Metabolic, V̇O$_textrm2$ kinetics, and muscle oxygenation responses at and above maximal lactate steady state in trained male rowers
This study aimed to compare physiological responses during rowing ergometer exercise at the maximal lactate steady state (MLSS) and 5% above the MLSS (MLSS+5%). Blood lactate concentration (BLC), oxygen uptake (V̇O2) kinetics, heart rate (HR), and …
Peak oxygen consumption is positively associated with estimates of oxygen extraction and microvascular blood volume in veterans with chronic kidney disease
Peak oxygen consumption (V_ O2peak) is reduced in patients with chronic kidney disease (CKD). Although cardiovascular and skeletal muscle factors are implicated in the declines of V_ O2peak, few studies have evaluated muscle oxygenation responses …
Preserved muscle oxidative capacity in COPD patients with hypoxemia treated by long term O2 therapy
Long-term oxygen therapy (LTOT) is an established treatment for patients with chronic obstructive pulmonary disease (COPD) diagnosed with hypoxemia at rest or during activity. Chronic hypoxemia is a potential mediator of loss of muscle mass and …
The effects of ischemic preconditioning and placebo maneuvers are similar during arm-cranking performance in upper-body trained athletes
This study aimed to examine the effects of local ischemic preconditioning (IPC) on 45 s arm-crank Wingate Anaerobic Test (WAnT) performance and accompanying physiological responses in athletes.
Thresholds Derived From Muscle NIRS Signal, Heart Rate Variability, and Ventilatory Parameters During an Incremental Cycling Test: An Agreement Analysis
This study aimed to compare different thresholds obtained from the muscle near-infrared spectroscopy (NIRS), heart rate variability (HRV), HR and ventilatory parameters during a maximal incremental cycling test. Twenty trained male cyclists performed …
Acute Effect of Inspiratory Muscle Training on Peripheral Tissue Oxygenation Behavior in Individuals With COPD: A Randomized Crossover Study
Background and Purpose Chronic Obstructive Pulmonary Disease (COPD) is a pulmonary condition characterized by airflow obstruction, which progresses with systemic alterations such as changes in muscle composition and metabolism, anticipating the …
Assessment of muscle oxygenation following eccentric exercise-induced muscle damage using near-infrared spectroscopy
Exercise-induced muscle damage (EIMD) disrupts muscle structure and function, impairing recovery and performance. Near-infrared spectroscopy (NIRS) offers a non-invasive method to assess muscle oxygenation, yet its sensitivity to EIMD-related changes …
The Acute Physiological Effects of Multiple Muscle Stimulation
Neuromuscular electrical stimulation (NMES) has been shown to provide health benefits similar to those of exercise. The aim of this study was to quantify the acute physiological effects of multiple muscle stimulation on the whole body and individual …
A Single Bout of Continuous Blood Flow Restriction Walking Does Not Negatively Affect Lower Limb Microvascular Function: Original Research
Introduction: Diminished macrovascular vasodilatory function has been reported following one blood flow restriction (BFR) walking bout. The primary aim was to investigate the potential effect that walking exercise (control, BFR) and cool-down …
Ischemic Preconditioning Does Not Improve Climbing Specific Performance in Elite Athletes
Platzer, H-P, Köck, A, Schobersberger, W, and Dünnwald, T. Ischemic preconditioning does not improve climbing specific performance in elite athletes. J Strength Cond Res 40(1): e69–e75, 2026—The aim of the present investigation was to analyze the …
Muscle oxygen consumption and microvascular function in healthy aging assessed by near-infrared spectroscopy: effect of adipose tissue thickness and physical fitness
A decline in skeletal muscle function is a key factor contributing to reduced functional capacity and quality of life with aging. While the mechanisms are multifactorial, impairments in mitochondrial and microvascular function are believed to play a …
Pulmonary Obstruction and Age, Not Activity, Associate With Muscle Oxidative Impairment in Smokers With and Without COPD
Background Low muscle oxidative capacity is an extrapulmonary manifestation of chronic obstructive pulmonary disease (COPD) with unclear aetiology. We sought to characterize locomotor muscle oxidative capacity in never smokers and ever smokers with …
Standard V̇ o2 measures underestimate metabolic demand during blood flow-restricted exercise
Systemic oxygen consumption (V_ O2) has traditionally been the gold standard for assessing aerobic metabolic demand. However, under conditions that alter normal blood flow or ventilation, such as blood flow restriction (BFR), V_ O2 may no longer reflect …
Steepest near-infrared spectroscopy-derived deoxygenation slopes during arterial occlusions provide more reliable assessments of muscle mitochondrial capacity
Assessment of near-infrared spectroscopy (NIRS)-derived muscle oxidative capacity relies on analysing deoxygenation slopes from NIRS signal versus time curves during brief arterial occlusions, which reflect the rate of post-exercise recovery of …
Acute physiological responses during repeated sprint training with maximum end-expiratory breath-holds
Purpose Repeated sprint training in hypoxia (RSH) performed with voluntary hypoventilation at low lung volumes (RSH-VHL) has been proposed as an alternative to RSH. Recently, repeated sprint training combined with end-expiratory breath hold until the …
Effects of fractional inspired O$_textrm2$ on the O$_textrm2$ pathway during submaximal and maximal exercise in male endurance athletes
We utilized non-invasive methods and novel computational approaches to examine the effects of acutely varying fractional inspired O2 (FIO2) on convective and diffusive steps of O2 transport and muscle tissue (de)oxygenation during incremental cycling …
417PA pilot study to explore a non-invasive measure of mitochondrial dysfunction
Grip strength is a simple and inexpensive clinical test. However, by limiting measurement to the force of an isolated contraction, we are missing functionally, and mechanistically relevant information. Skeletal muscle ATP consumption can increase …