Wearable sensors for monitoring sports performance and training

Abstract

Textile based devices for biochemical analysis of body fluids represent a new development in the area of wearable sensors. This paper outlines the development of a fluid handling system and wireless sensors for the real-time analysis of sweat pH and sodium levels during exercise. Liquid is drawn into the system using a moisture wicking material and passive pump. The sensor then displays pH induced colorimetric changes, which are recorded using an optical detection system. The device has been tested under laboratory conditions and can easily detect increments of 0.2 pH units. At present, changes in sodium content are determined using a specially constructed classic ion selective electrode and reference electrode, combined to form a single probe. This is placed in contact with the fabric of the fluid handling system in order to obtain a real-time potentiometric sodium measurement. Both devices have successfully been used for the investigation of sweat composition during on-body trials.