Title:“Measuring Muscle Oxygenation in Endurance Sports with Wearable NIRS – From Validation to Application”
Thesis Supervisor: Dr. Michael Koehle
Committee Members: Dr. Jordan Guenette, Dr. Dave Clarke, Dr. Ben Sporer
Chair: Dr Nicola Hodges
Abstract: Wearable NIRS devices are becoming more suitable for field application, with better ergonomic design, connectivity to smart watches and sport computers, and the ability to monitor multiple muscle sites simultaneously. Despite an increasing popularity of wearable NIRS use in research, the validity, reproducibility, and comparability of wearable NIRS with other endurance performance markers remains unreported. This gap must be addressed to advance the use of NIRS as a tool capable of measuring the capacity for peripheral working muscle to extract oxygen to produce mechanical work. This is a key factor for athletic performance, with muscle tissue hypoxia being a known limiting factor to exercise tolerance. Many studies have shown the importance of measuring muscle oxygenation (SmO2) using near infrared spectroscopy (NIRS) in athletes, both during a single training bout and across a training cycle. Assessing muscle oxygenation in conjunction with cardiopulmonary measurements yields an interrelated measure of O2 transport within the cardiovascular system and peripheral muscles. As with other physiological markers used to track physical exercise, it is important to correctly interpret the NIRS signals, while comparing the profiles with established metabolic markers during exercise. Wearable NIRS devices use high frequency sampling (0.5 – 2Hz) which allows interpretation of onset and recovery kinetics during stochastic type exercise, even during short bout (5 – 10s) maximal efforts. Wearable NIRS devices are becoming more suitable for field applications, with better ergonomic design and connectivity to smart watches and sport computers. Validating and establishing guidelines for data interpretation in the context of sport science will allow athletes, coaches, and researchers to collect reliable measures of muscle oxygenation. The aim of this proposed body of work is to validate and investigate the applicability of wearable NIRS for endurance performance.