ABSTRACT
The work of breathing occupied a quiet spot in the field of physiology until the 1950s (Milic Emili, 1991) although the scientific foundations for much of the subsequent research were provided by Liljestrand (1918) and Rohner (1925) more than 70 years ago. In the last 25 years there has been growing interest in respiratory muscle energetics in the normal subject, and the major issues in this area have been discussed in several excellent reviews and original works (Hill, 1964; Momrnaerts, 1969 Wilkie, 1974; Gibbs, 1978; Homsher and Kean, 1978; Curtin and Woldge, 1978; Gibbs and Chapman, 1979; Roussos, 1985).
