Spielvogel H, Caceres E, Koubi H, Sempore B, Sauvain M, Favier R
Instituto Boliviano de Biologia de Altura, La Paz, Bolivia.
J Appl Physiol (1985). 1996 Feb;80(2):643-9. doi: 10.1152/jappl.1996.80.2.643.
We examined the effects of 1 h 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 with a group of nonchewers (n = 13). For 1 h, C chewed approximately 12 g of coca leaves that resulted in the apparition of cocaine in blood that reached 72 +/- 9 ng/ml. In resting conditions, even though 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. Oxygen uptake measured at exhaustion and delta work efficiency during exercise were similar in both groups. During the incremental exercise, C displayed a significantly lower arterial oxygen saturation that cannot be explained by a reduced ventilatory response after coca chewing. In fact, even at maximal exercise, both ventilatory output and ventilatory equivalent were higher in C compared with nonchewers. 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 an increased work efficiency. However, during incremental exercise, coca chewing appeared to result in an increased free fatty acid availability that could be beneficial for prolonged submaximal exercise.
我们研究了古柯咀嚼者（C组；n = 8）在进行递增运动直至力竭过程中，咀嚼1小时古柯对代谢和激素反应的影响，并将结果与一组非咀嚼者（n = 13）进行比较。在1小时内，C组咀嚼了约12克古柯叶，导致血液中出现可卡因，浓度达到72±9纳克/毫升。在静息状态下，尽管两组的交感肾上腺素能活性（通过去甲肾上腺素和肾上腺素血浆水平评估）相似，但C组的血浆游离脂肪酸水平较高。两组在力竭时测得的摄氧量和运动期间的增量工作效率相似。在递增运动期间，C组的动脉血氧饱和度显著较低，这不能用咀嚼古柯后通气反应降低来解释。事实上，即使在最大运动时，C组的通气量和通气当量也比非咀嚼者高。得出的结论是，传统古柯使用者经常报告的咀嚼古柯对运动耐力的有益影响，既与最大运动能力的提高无关，也与工作效率的增加无关。然而，在递增运动期间，咀嚼古柯似乎会导致游离脂肪酸可用性增加，这可能对长时间的次最大运动有益。
