Table 4.

Investigations examining the effects of caffeinated chewing gum on caffeine absorption and exercise performance

Author	Participants	Protocol	Results
Kamimori et al. 2002 [58]	Healthy males (n = 84; 12 per group)	• 50 mg caffeine capsule • 50 mg caffeine gum • 100 mg caffeine capsule • 100 mg caffeine gum • 200 mg caffeine capsule • 200 mg caffeine gum • Placebo	Both 100 and 200 mg of caffeine in gum and capsule formualtions provide comparable amounts of caffeine to the systemic circulation. Mean Tmax for the gum groups ranged from 44.2 to 80.4 min as compared with 84.0–120.0 min for the capsule groups
Ryan et al. 2012 [59]	College-aged, physically active males (n = 8)	• 200 mg caffeinated gum • Placebo gum	⬌ cycling TTE
Ryan et al. 2013 [60]	Well-trained male cyclists (n = 8)	• 300 mg caffeine gum • Placebo gum	*↑ cycling TT performance when 300 mg caffeine chewing gum was administered 5 min pre-TT
Lane et al. 2014 [61]	Well-trained males (n = 12) and females (n = 12)	• 3 mg/kg caffeine gum 40 min prior + 1 mg/kg 10 min prior • Placebo gum • Beet root juice • Beet root juice w/ caffeine	*↑ cycling TT performance by 3–4% Note: participant’s sex was accounted for during testing (female: 29.35 km; male: 43.83 km)
Oberlin-Brown et al. 2016 [62]	Well-trained male cyclists (n = 11)	• 200 mg caffeine gum • 200 mg caffeine + CHO gum • CHO gum • Placebo gum	⬌ cycling TT performance
Paton et al. 2015 [63]	Well-trained male (n = 10) and female (n = 10) cyclists	• ~ 3–4 mg/kg caffeine gum • Placebo gum	~ 3–4 mg/kg enhanced both endurance (> 5 min) and sprint power output (< 30 s) by similar amounts (~ 4%) during the final 10 km of a 30-km race
Paton et al. 2010 [64]	Competitive male cyclists (n = 9)	• 3 mg/kg caffeine gum • Placebo gum	*↓ power output decline in 3rd & 4th sprints
Bellar et al. 2012 [65]	Collegiate shot-put athletes (n = 9)	• 100 mg caffeine gum • Placebo gum	*↑ shot-put performance
Ranchordas et al. 2018 [66]	Collegiate male soccer players (n = 10)	• 200 mg caffeine gum • Placebo gum	*↑ Yo-Yo Intermittent Recovery Test level 1 and countermovement jump
Venier et al. 2019 [67, 68]	Resistance-trained men (n = 19)	• 300 mg caffeine gum • Placebo gum	*↑ Jumping height *↑ Isokinetic strength and power *↑ Movement velocity in the bench press *↑ Whole-body power output

Bold text associated with reported trial outcomes; * delineates a significant change, NS = non-significant change, TT = Time Trial, TTE = time to exhaustion, ⬌ = no improvement/change, ↑ = improved performance, ↓ = decreased, min = minute, CHO = carbohydrate, seg = segment, T_max = maximum concentration, km = kilometers