Caffeine and Exercise Performance: Possible Directions for Definitive Findings

Abstract

Caffeine is one of the most studied supplements in the world. Studies correlate its use to increased exercise performance in endurance activities, as well as its possible ergogenic effects for both intermittent and strength activities. Recent findings show that caffeine may increase or decrease exercise performance. These antagonist responses may occur even when using the same dosage and for individuals with the same characteristics, making it challenging to explain caffeine's impact and applicability. This review article provides an analytic look at studies involving the use of caffeine for human physical performance, and addresses factors that could influence the ergogenic effects of caffeine on different proposed activities. These factors subdivide into caffeine effects, daily habits, physiological factors, and genetic factors. Each variable has been focused on by discussions to research related to caffeine. A better understanding and control of these variables should be considered in future research into personalized nutritional strategies.

Acute Effects of Low Dose of Caffeine Ingestion Combined with Conditioning Activity on Psychological and Physical Performances of Male and Female Taekwondo Athletes

“…However, even though they have the same genotypes, it has been suggested that females require a longer time to metabolize CAF than males [ 15 ]. This fact could be explained by the greater half-life of CAF in females than in males [ 14 ]. Moreover, the effect of CAF was reported to be greater in individuals with larger muscle mass [ 59 ].…”

“…This difference could be related to the methodological and the inter-individual variations. In fact, the ergogenic effects of CAF are influenced by participants’ characteristics (i.e., sex, age, training status), CAF supplementation protocol (i.e., dose, form, ingestion time, time of day of CAF supply), tolerance to CAF, genetics, and nature of exercise [ 3 , 7 , 14 , 15 , 16 , 17 ].…”

Energy Drinks and Sports Performance, Cardiovascular Risk, and Genetic Associations; Future Prospects

“…According to the recent review of caffeine in the context of athletic performance published by Martins et al [128] improvements in performance were noted at doses of 2-9 mg/kg. This is notable because the physiological mechanisms that are involved when the dose is increased remain unclear, since the subject's regular consumption and the time of day when the caffeine is taken may have positive or negative effects on the ensuing benefits.…”

Caffeine Increases Performance and Leads to a Cardioprotective Effect During Intense Exercise in Cyclists: a Randomized, Double-blind, Crossover, Placebo-controlled Study

“…Some authors defend its use a high dose only on the competition's day, after a withdrawal from any CAF source during the training period, since it is hypothesized that this strategy could enhance its ergogenic effect [18][19][20] . On the other hand, despite the ndings of studies [21][22][23] that indicate tolerance to ergogenic effects with the regular use of CAF, other authors recommend the use of doses that represent an average amount of caffeine above the usual (i.e., reducing the tolerance effect), having its ergogenic effect potentiated 4,5 .…”