Evaluation of muscle aging with TD NIRS and DCS

Muscle aging is characterized by the loss of muscle mass and strength that starts mostly after 50yr and, according to the World Health Organization (2000), it is one of the major causes of independence loss and a risk factor for the development of morbidities at older age. Early diagnosis and treatment are paramount for the progression of the disease. The “Trajector-AGE” project focuses on the study of neuromuscular decline in middle-aged and old populations. Within this project, different techniques are exploited to investigate muscle health (e.g., biopsy, electromyography, Near Infrared Spectroscopy), and among them, Time Domain Near Infrared Spectroscopy (TD-NIRS) and diffuse correlation spectroscopy (DCS) are non-invasive optical techniques which enable to assess muscle oxidative metabolism and perfusion respectively. During the project life, we plan to recruit 100 individuals to evaluate differences among the hemodynamics and microcirculation responses of the vastus lateralis to arterial occlusion and incremental cycling in different age-groups (55–60yrs, middle-aged population; 75-80yrs, old population). The main parameters extrapolated will be the time courses for oxy- (HbO2), deoxy- (HHb), total- hemoglobin (tHb), tissue oxygen saturation (StO2) and blood flow index (BFI). From these, biomarkers for the neuromuscular decline will be defined. At the time of this work, 21 subjects were already acquired. Here, we present the preliminary results from 1 healthy volunteer.