Graham T, Battram D, Dela F, El Sohemy A, Thong F. Does caffeine alter muscle carbohydrate and fat metabolism during exercise?. Appl Physiol Nutr Metab. 2008;33:1311-8 pubmed publisher
..Individuals may, however, respond differently to the effects of caffeine, and there is growing evidence that this could be explained by common genetic variations. ..
Graham T, Adamo K, Shearer J, Marchand I, Saltin B. Pro- and macroglycogenolysis: relationship with exercise intensity and duration. J Appl Physiol (1985). 2001;90:873-9 pubmed
..0 and 10.8 +/- 5.6. The MG pool appeared to be more resistant to mobilization, and, when activated, its catabolism was inhibited more rapidly than that of PG. This suggests that the metabolic regulation of the two pools must be different...