The Effect Of Novel Low Dose Caffeine Products On Physical Performance: A Pilot

Caffeine is often used as an ergogenic aid to reduce fatigue, increase arousal, and improve physical and cognitive performance. Recommended caffeine doses to elicit an ergogenic response are 3-6 mg/kg BM, although evidence exists to support lower doses (<3 mg/kg). However, evidence is conflicting, and with novel pouch-based and gum products providing low caffeine doses, further research is required to establish any ergogenic effect. PURPOSE: To investigate the effects of novel low-dose caffeine products on muscular endurance, strength, and power. METHODS: A repeated-measures, crossover design with three conditions (caffeinated pouch 80 mg, caffeinated gum 80 mg, non-caffeinated gum control 0 mg) was employed, recruiting six males and seven females (age: 23.2 + 6.8 yrs; weight: 73.3 + 28.6 kg; relative caffeine dose: 1.2 + 0.2 mg/kg). Familiarisation was completed prior to the experimental trials whereby 1RM for the leg press (LP) and shoulder press (SP) were measured. Participants then completed a battery of physical tests that included a 60% 1RM single LP and SP to exhaustion, counter-movement jump, and an isometric mid-thigh pull (IMTP), in addition to rating of perceived exertion (RPE) during endurance tests. A one-way repeated measures ANOVA was conducted on all measures associated with physical tasks. RESULTS: Effect size for these performance measures, employing Cohen D classification, identified moderate (d = 0.68) and small (d = 0.40) effects for the caffeine pouch and caffeine gum compared to placebo for the LP respectively. Further, small effects (d = 0.26; d = 23) for the SP were observed. Comparing the placebo with the caffeine products identified increases in RPE during the endurance bouts highlighting moderate (d = 0.5) and small (d = 0.33) effects for the SP with the pouch and gum respectively, and small effects during the LP (d = 0.35; d = 0.46). Effect sizes for the caffeine products for strength and power resulted in negligible results (d < 0.2). CONCLUSIONS: Low dose caffeine has the potential to produce meaningful effects on strength endurance, likely linked to caffeine mechanisms reducing RPE and maintaining muscle contractility.