Effects of Caffeine on Repetitions to Failure and Ratings of Perceived Exertion During Resistance Training

Abstract

Context: Ergogenic effects of caffeine on aerobic or endurance exercise are well documented. Conversely, the ergogenic value of caffeine on high-intensity, primarily anaerobic performance is not well understood even though the proposed mechanisms of action for caffeine permit a strong theoretical basis for application to this type of exercise. Purpose: This study examined effects of caffeine (Ca) on number repetitions (reps), ratings of perceived exertion (RPE), and peak heart rate (PHR) during resistance-training exercise with reps performed to volitional failure. Methods: Subjects (N = 17) were tested for 10-rep maximum in bench press (BP) and leg press (LP). In sessions 2 and 3, Ca (~6 mg/kg) or placebo (Pl) was ingested 1 hr beforehand in a double-blind manner and counterbalanced order. Subjects performed 3 sets to failure (BP and LP) with reps, PHR, and RPE recorded each set. Repeated-measures ANOVAs, 2 (trial) × 3 (set), were used to analyze dependent measures with the Tukey honestly significant difference used when necessary as the post hoc test. Results: In BP, no significant differences (Ca vs Pl) were observed (reps, RPE, PHR). During set 3 of LP training, Ca was associated with significantly higher reps (12.5 ± 4.2 vs 9.9 ± 2.6) and PHR (158.5 ± 11.9 vs 151.8 ± 13.2). No significant RPE differences were found during LP. Conclusions: The findings of similar RPE concurrent with higher reps suggest that caffeine can blunt pain responses, possibly delaying fatigue in high-intensity resistance training. Ergogenic effects might be limited to the later sets in a resistance-training session. Further research is warranted regarding ergogenic effects of caffeine during resistance training and potential mechanisms of action.Caffeine can enhance endurance-based exercise performance with ergogenic properties attributed to mechanisms such as enhanced free-fatty-acid mobilization 1,2

Effects of Pre-Workout Supplements on Power Maintenance in Lower Body and Upper Body Tasks

“…Previous research suggested that a pre-workout supplement with similar ingredients improved lower body muscular endurance [4], whereas other past studies involving similar pre-workout supplements have shown no power increases during anaerobic power tests with the use of a preworkout type supplement [27]. The results of this study also did not find any significant effect on power performance increases over the length of the high-intensity cycle testing battery for any of the treatment conditions.…”

Ingestion of a Nitric Oxide Enhancing Supplement Improves Resistance Exercise Performance

“…This was followed by a one minute rest period that took place after each warm up set. Testing procedures then began perfroming sets of repetitions to failure using a load of 60% of 1-RM, with each set separated by a two minute rest period (8,15). Number of repetitions, total weight lifted, local ratings of perceived exertion (RPE) were recorded on completion of each set using 1-10 scales where 1 represented no exertion at all and 10 being maximal extertion.…”

“…Participants were required to abstain from ingesting ergogenic supplements during the data collection period. Furthermore, they were also required to replicate dietary intakes for the 24 hr prior to each laboratory visit, avoid exhaustive exercise (9) and limit caffeine consumption (15). Prior to each laboratory visit the participants were instructed to eat no less than three hours prior to the 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 5 trials and consume only water in the final hour before testing commenced (9).…”

Eficácia ergogênica da suplementação de cafeína sobre o desempenho de força? Uma análise crítica.

“…Além disso, é importante ressaltar que não se pode afirmar que não houve interação da cafeína com os outros componentes do suplemento (guaraná, extrato de chá verde/preto, vitamina C e outros). No ano seguinte, utilizando uma dose de cafeína superior aos estudos já mencionados, Green et al (2007) avaliaram o efeito da suplementação aguda de 6 mg/kg de cafeína sobre o número de repetições realizadas até a exaustão nos exercícios supino e leg press durante 3 séries a uma carga de 10-RM. Interessantemente, os autores verificaram que a suplementação de cafeína proporcionou um significante aumento no número de repetições realizadas no leg press em comparação à condição placebo (12,5 ± 4,2 vs. 9,9 ± 2,6).…”