Peripheral impairments of oxidative metabolism after a 10-day bed rest are upstream of mitochondrial respiration

In order to identify peripheral biomarkers of impaired oxidative metabolism during exercise following a 10-day bed rest, 10 males performed an incremental exercise (to determine peak pulmonary V˙O 2 (V˙O 2 p)) and moderate-intensity exercises, before …

Circulating biomarkers of nitric oxide bioactivity and impaired muscle vasoreactivity to exercise in adults with uncomplicated type 1 diabetes

Aims/hypothesis: Early compromised endothelial function challenges the ability of individuals with type 1 diabetes to perform normal physical exercise. The exact mechanisms underlying this vascular limitation remain unknown, but may involve either …

Interpretation of near-infrared spectroscopy (NIRS) signals in skeletal muscle

Near-infrared spectroscopy (NIRS) uses the relative absorption of light at 850 and 760 nm to determine skeletal muscle oxygen saturation. Previous studies have used the ratio of both signals to report muscle oxygen saturation. Purpose: The purpose of …

Regional differences in mitochondrial capacity in the finger flexors of piano players

Background: Near-infrared spectroscopy (NIRS) has been used to measure oxidative capacity, but regional differences have not been identified. Piano players are also a novel group of subjects for this lab. Methods: Controls (n = 13) and piano players …

An Investigation into the Effect of Skeletal Muscle Metabolic Function & Cardio-Respiratory Fitness on Exercise Capacity in the Presence and Absence of Disease

It is uncommon for cardio-respiratory fitness and skeletal muscle metabolic function to be assessed independently within an exercise test. Exercise capacity may require adaptation of one or other of these systems to a greater or lesser extent and the …

Critical determinants of combined sprint and endurance performance: An integrative analysis from muscle fiber to the human body

Optimizing physical performance is a major goal in current physiology. However, basic understanding of combining high sprint and endurance performance is currently lacking. This study identifies critical determinants of combined sprint and endurance …

Reproducibility of NIRS assessment of muscle oxidative capacity in smokers with and without COPD

Low muscle oxidative capacity contributes to exercise intolerance in chronic obstructive pulmonary disease (COPD). Near-infrared spectroscopy (NIRS) allows non-invasive determination of the muscle oxygen consumption (mV̇O2) recovery rate constant …

Impact of flavonoid-rich black tea and beetroot juice on postprandial peripheral vascular resistance and glucose homeostasis in obese, insulin-resistant men: A randomized controlled trial

Background: Insulin-stimulated muscle blood flow facilitates plasma glucose disposal after a meal, a mechanism that is impaired in obese, insulin-resistant volunteers. Nitrate- or flavonoid-rich products, through their proposed effects on nitric …

Noninvasive measurement of lower extremity muscle oxygen extraction fraction under cuff compression paradigm

Background To demonstrate the feasibility of using a susceptibility-based MRI technique with asymmetric spin-echo (ASE) sequence to assess the lower extremity muscle oxygen extraction fraction (OEF) alternations under cuff compression paradigm. …

Recent developments in near-infrared spectroscopy (NIRS) for the assessment of local skeletal muscle microvascular function and capacity to utilise oxygen

Purpose of review Continuous wave near infrared spectroscopy (CW NIRS) provides non-invasive technology to measure relative changes in oxy- and deoxy-haemoglobin in a dynamic environment. This allows determination of local skeletal muscle O2 …

Influence of exercise training with resveratrol supplementation on skeletal muscle mitochondrial capacity

Physical inactivity reduces, and exercise training increases, mitochondrial capacity. In rodents, exercise training effects can be augmented by large doses of resveratrol supplementation but whether this can occur in humans with a smaller dose is …

The use of near-infrared spectroscopy in understanding skeletal muscle physiology: Recent developments

This article provides a snapshot of muscle near-infrared spectroscopy (NIRS) at the end of 2010 summarizing the recent literature, offering the present status and perspectives of the NIRS instrumentation and methods, describing the main NIRS studies …

Nonuniform quadriceps O2 consumption revealed by near infrared multipoint measurements

Single location muscle monitoring does not reflect the heterogeneous activation of the muscle group(s) during a given exercise. Vastus lateralis and rectus femoris O2 consumption (VO2) was investigated, non-invasively, at rest and during maximal …