Dose and preparation of coffees
High-dose espresso coffee (HDC) drink was obtained from the combination of 14 g of caffeinated ground coffee (Lavazza Espresso Italiano, double shot). Placebo (PLA) was obtained from the combination of 14 g of decaffeinated ground coffee (Lavazza Espresso Decaffeinato, double shot). Low-dose espresso coffee (LDC) drink was obtained from the combination of 7 g of caffeinated ground coffee and 7 g of decaffeinated ground coffee. The approximate amount of caffeine in LDC, HDC, and PLA was 60 mg, 125 mg, and 10 mg, respectively. The amount and temperature (180–190 F