Effects of coca chewing on metabolic and hormonal changes during graded incremental exercise to maximum. Spielvogel, Hilde, Esperanza Caceres, Harry Koubi, Brigitte Sempore, Michel Sauvain, and Roland Favier. Instituto Boliviano de Biologia de Altura, Casilla 717 - La Paz -Bolivia, URA 1341 CNRS - Laboratoire de Physiologie, Universit[acute]e Claude Bernard, 69373 Lyon Cedex08 - France, Institut Fran[cedilla]cais de Recherche Scientifique pour le D[acute]eveloppement en Coop[acute]eration (ORSTOM) - Casilla 9214 - La Paz - Bolivia
APStracts 2:0429A, 1995.
We examined the effects of one hour of coca chewing on metabolic and hormonal responses during incremental exercise to exhaustion in traditional coca chewers (C, n=8) and the results were compared to a group of non-chewers (NC, n=13). During one hour, C chewed approximately 12 grams of coca leaves which resulted in the apparition of cocaine in blood which reached 72 +/- 9 ng/ml. In resting conditions, eventhough sympathoadrenergic activity (as assessed by norepinephrine and epinephrine plasma levels) was similar in both groups, C displayed a higher level of plasma free fatty acids (FFA). Oxygen uptake measured at exhaustion (VO2peak) and delta work efficiency (h) during exercise were similar in both groups. During the incremental exercise, C displayed a significantly lower arterial oxygen saturation (SaO2) which cannot be explained by a reduced ventilatory response after coca chewing. In fact, even at maximal exercise, both ventilatory output and ventilatory equivalent (VE /VO2) were higher in C as compared to NC. It is concluded that the beneficial effects of coca chewing on exercise tolerance reported frequently by traditional coca users is not related to either an improved maximal exercise capacity or to an increased work efficiency. However, during incremental exercise, coca chewing appeared to result in an increased FFA availability which could be beneficial for prolonged submaximal exercise. 

Received 6 March 1995; accepted in final form 15 September 1995.
APS Manuscript Number A251-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 6 November 95