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Ryan, EJ, Kim, C-H, Fickes, EJ, Williamson, M, Muller, MD, Barkley, JE, Gunstad, J, and Glickman, EL. Caffeine gum and cycling performance: A timing study. J Strength Cond Res 27(1): 259–264, 2013—The purpose of this study was to determine the most efficacious time to administer caffeine (CAF) in chewing gum to enhance cycling performance. Eight male cyclists participated in 5 separate laboratory sessions. During the first visit, the subjects underwent a graded exercise test to determine maximal oxygen consumption (V[Combining Dot Above]O2max). During the next 4 visits, 3 pieces of chewing gum were administered at 3 time points (120-minute precycling, 60-minute precycling, and 5-minute precycling). In 3 of the 4 visits, at 1 of the time points mentioned previously, 300 mg of CAF was administered. During the fourth visit, placebo gum was administered at all 3 time points. The experimental trials were defined as follows: trial A (–120), trial B (–60), trial C (–5), and trial D (Placebo). After baseline measurements, time allotted for gum administration, and a standard warm-up, the participants cycled at 75% V[Combining Dot Above]O2max for 15 minutes then completed a 7-kJ·kg−1 cycling time trial. Data were analyzed using a repeated measures analysis of variance. Cycling performance was improved in trial C (–5), but not in trial A (–120) or trial B (–60), relative to trial D (Placebo). CAF administered in chewing gum enhanced cycling performance when administered immediately prior, but not when administered 1 or 2 hours before cycling.