Caffeine and neuromuscular performance in powerlifting: a real advantage?

Caffeine is undoubtedly the most widely consumed ergogenic substance in the world, both in everyday life and in high-level sports. It is naturally present in coffee, tea, cocoa, certain energy drinks, and many supplements. For several decades, its effect on physical performance has fascinated researchers and athletes alike.

In the central nervous system, caffeine acts as an antagonist of adenosine A2A receptors, which leads to hypoalgesia (decreased pain perception) and increases alertness, thereby potentially reducing  rate perceived exertion (RPE). In skeletal muscles, caffeine also stimulates the release of calcium from the sarcoplasmic reticulum, leading to increased muscle fiber excitability and motor unit recruitment. Therefore, in tasks where results are largely determined by neuromuscular performance (strength and power-based efforts), the ergogenic effects of caffeine would be particularly relevant, as in the case of powerlifting…

Powerlifting consists of three movements: the squat, the bench press, and the deadlift. The goal is to lift as much weight as possible in these three exercises, in three attempts. Performance therefore relies on brief but maximal muscle contractions, where neuromuscular fatigue and the perception of effort play a key role. In this context, caffeine is often used as a boost before exercise, supposedly to improve power, concentration, and pain tolerance.

However, although the effectiveness of caffeine on endurance performance is well established, the results regarding its effectiveness on muscle strength remain mixed, particularly in terms of the optimal dose, differences between exercises, and the actual magnitude of the effect. Some results show that 6 mg/kg of caffeine has no effect on bench press or leg press strength compared to placebo, while other results have found an improvement in upper body strength with the same dose. A meta-analysis revealed that caffeine improves 1RM muscle strength compared to placebo, but it is interesting to note that the sub-analysis revealed no effect on lower body strength. What is its real impact on strength and power, particularly in powerlifting?

The study

To attempt to answer this question, a study published in 2025 focused on the effect of a dose of caffeine on neuromuscular performance (in terms of speed, power, fatigue, and perceived exertion) on two iconic movements, the squat and the deadlift, in powerlifters. The study was conducted according to a randomized, controlled, quadruple-blind protocol. In practical terms, neither the participants nor the researchers involved in the collection, analysis, or distribution of the capsules knew who was receiving caffeine or the placebo.

Sixteen male powerlifting athletes participated in the study. All had at least two years of regional competition experience, with a strength-to-body weight ratio greater than 1.5 for squats and 1.8 for deadlifts. Their average age was 26 and their average body mass was 88 kg. Their baseline 1RM (one repetition maximum) averages were 181.0 ± 44.7 kg for the squat and 215.0 ± 38.8 kg for the deadlift.

The protocol was conducted over three sessions spaced one week apart. The first session was used to measure the 1RM for each exercise, following the technical standards of the International Powerlifting Federation. The other two experimental sessions consisted of performing sets of 3 repetitions at different intensities (40, 60, 80, and 90% of 1RM) after ingesting the test substance:

Participants ingested the capsules one hour before the session, the time required to reach maximum plasma caffeine concentration. They then performed three repetitions at each load intensity for the squat and then the deadlift, with rest periods of three to five minutes between sets. The variables measured included:

The athletes also completed a food diary to monitor their energy intake and usual caffeine consumption, estimated at an average of 157 mg per day (approximately two cups of coffee). They were required to abstain from all sources of caffeine and intense training in the 24 hours prior to each session.

Results & Analysis

The main results confirmed that caffeine has a real ergogenic effect on strength-speed performance, improving neuromuscular performance in squats and deadlifts, particularly in a context of near-maximal effort (80-90% of 1RM).

Squat

Compared to the placebo, the average speed of the bar was significantly higher with caffeine at all intensities: +5% at 40% of 1RM, +5% at 60% of 1RM, +17% at 80% of 1RM, and +21% at 90% of 1RM. The greater the load, the more pronounced the advantage of caffeine. The average power followed the same trend, reaching +18% at 90% of 1RM. The loss of speed, an indicator of fatigue over repetitions, was reduced by 25% at 80% of 1RM and by 30% at 90% of 1RM. In other words, the athletes maintained their power better on the two heaviest loads tested. Finally, the perceived exertion (RPE) was lower overall in the caffeine condition, but not statistically significant.

In the deadlift

The trends were similar: caffeine increased average speed at all loads, from +10% to 40% of 1RM to +12% to 90% of 1RM. Average power was slightly higher (+5 to 8%), although the difference was not statistically significant, probably due to interindividual variability. The loss of speed was significantly reduced from 24% to 80% of 1RM and from 27% to 90% of 1RM, confirming a positive effect on neuromuscular fatigue resistance. As for RPE, it also decreased slightly, especially at heavy loads.

No significant difference was observed in speed loss at light loads (40-60% of 1RM), suggesting that the ergogenic effect of caffeine is mainly evident when mechanical and neural stress is high. The researchers also noted that half of the athletes guessed the experimental condition due to symptoms typical of caffeine intake: tachycardia, nervousness, and mild anxiety. However, no serious adverse effects were reported, and these sensations did not interfere with performance.

There are multiple mechanisms at play. Centrally, caffeine acts as an antagonist of adenosine receptors, an inhibitory neurotransmitter involved in the sensation of fatigue and pain. By blocking these receptors, caffeine increases alertness, decreases the perception of effort, and delays the onset of mental fatigue. Peripherally, caffeine promotes the release of calcium from the sarcoplasmic reticulum, improving muscle contraction and motor unit synchronization. These effects, which have been well documented in the laboratory, translate here into a measurable increase in speed and power, as well as less loss of performance during heavy repetitions.

The dose used in this study (8 mg/kg, or approximately 640 mg for an 80 kg athlete—the equivalent of 6 to 8 espressos) is high, exceeding the standard recommendations of 3 to 6 mg/kg. Some authors have suggested that Ca2+ release follows a dose-response pattern related to caffeine. However, the effects observed here suggest that higher doses may be necessary for athletes who are already accustomed to caffeine and for efforts close to maximum (80-90% of 1RM). This is consistent with several studies indicating that a higher level of neuromuscular activation is necessary to fully benefit from supplementation.

However, this effect is not universal. Genetic variations (particularly in the CYP1A2 and ADORA2A genes) influence the rate of caffeine metabolism and sensitivity to side effects. Some individuals experience a net benefit, while others do not, or even experience adverse effects (excessive nervousness, loss of coordination, anxiety). This is why caffeine and its dosage should be tested during training before any use in competition.

The study also highlights a methodological limitation: the difference in energy intake between the two conditions (approximately 450 kcal more in the placebo condition), which could theoretically influence performance. However, this difference is not sufficient to call the results into question, especially since the effect observed on speed and power is consistent with the literature.

Finally, it should be noted that this study evaluates acute effects, i.e., over a single session. It is not yet known whether chronic supplementation, repeated at each training session, would produce the same effects or be accompanied by progressive tolerance.

Practical applications

For strength athletes, these results confirm that caffeine can be a useful ergogenic aid, but only if used wisely. From a practical standpoint, the effective dose is between 6 and 8 mg/kg, taken approximately 60 minutes before exercise. Below this, the effects on speed and power are more variable; above this, the risk of adverse effects increases. For an 80 kg athlete, this still represents 480 to 640 mg of caffeine. This amount is difficult to achieve with coffee alone, but is possible with standardized supplements.

Athletes must also take into account their habituation. Caffeine affects people differently. Some highly reactive athletes may experience unpleasant side effects (tachycardia, tremors, anxiety). In these cases, performance may be impaired rather than improved. The best dosage is therefore the one validated individually during training, in conditions similar to those of competition. And even though some authors and strength coaches recommend reducing caffeine intake outside of competitions in order to maintain sensitivity during key sessions, a 2022 meta-analysis showed that daily caffeine consumption does not necessarily reduce the ergogenic effect of occasional supplementation (read this article). In summary, this study provides solid evidence that caffeine improves acute neuromuscular performance in powerlifting by increasing execution speed and power output and reducing fatigue and perceived exertion (especially at high loads). However, it also reminds us that these benefits are highly dependent on dosage, individual sensitivity, and context of use.

Caffeine seems particularly useful in sessions where the load exceeds 75% of 1RM, i.e., pure strength or maximum power sessions. In lighter or muscular endurance efforts, the effect remains present but is more moderate. Its use must therefore be carefully considered, tested, and integrated into an overall performance strategy. Like any ergogenic aid, it is just another tool to be used with precision (and caution). Effective for those who tolerate it well, but secondary to what really drives progress: training, recovery, and consistency.

Reference

Enes, A., Salles, G. N., Ferreira, L. H. B., Rezende, E. F., Mohan, A. E., Leonel, D. F., Cruz, R., & Schoenfeld, B. J. (2025). Effects of Caffeine Supplementation on Neuromuscular Performance in Powerlifting Athletes: A Randomized, Placebo-Controlled, Quadruple-Blinded, Cross-Over Study. J Strength Cond Res.