A new study published in the journal Nutrients found that a combination of creatine nitrate and caffeine significantly improves cognitive function, more effectively than caffeine alone. However, this combination does not improve physical performance. This research offers valuable information to those looking to improve their mental acuity through dietary supplements.
Athletes and fitness enthusiasts often use dietary supplements like caffeine and creatine to improve their performance. Caffeine is known for its ability to reduce fatigue and improve alertness. Creatine, especially creatine monohydrate, helps quickly replenish adenosine triphosphate (ATP), which is crucial for short bursts of high-intensity exercise. Creatine nitrate, a newer form, is thought to provide the benefits of creatine while enhancing nitric oxide production, which can improve blood circulation and muscle oxygenation.
Despite the known benefits of these supplements taken individually, the effects of combining them have been less studied. Some data suggest potential interactions that could either amplify or diminish their benefits. In their new study, the researchers aimed to evaluate the effects on cognitive and physical performance of a week’s high intake of caffeine, creatine nitrate, and their combination in resistance-trained men.
“I was intrigued by the potential ergogenic and cognitive benefits of creatine and caffeine, which are well documented individually but less understood when combined. Given their popularity among athletes, it was important to explore whether their combination could produce synergistic benefits, particularly in improving physical and cognitive performance,” said study author Majid Koozehchian, associate professor of kinesiology at Jacksonville State University.
The study took place at the Human Performance Laboratory at Jacksonville State University. Recruitment targeted resistance-trained men with at least two years of multi-joint resistance training experience. Participants were asked to maintain their usual workout and eating habits and avoid new exercise or diet changes during the study.
The final sample included 12 participants, aged 18 to 40, meeting strict inclusion criteria. They had to be free of metabolic disorders, cardiovascular diseases and other specific health conditions, and not take prescription medications. They also had to have a body mass index (BMI) between 18.5 and 24.9 and no known intolerance to caffeine or natural stimulants.
Participants completed a familiarization session during which they practiced exercise testing and provided baseline health information. The study followed a double-blind, placebo-controlled, crossover design, with participants passing through four treatment phases: creatine nitrate, caffeine, their combination, and placebo. Each phase lasted seven days, separated by a one-week washout period.
The supplements included 5 grams of creatine nitrate, 400 milligrams of caffeine, a combination of the two, or a maltodextrin placebo. These were administered 45 minutes before the exercise tests. The rationale for the dosages was based on previous research showing that these amounts could improve performance and cognitive function.
Performance was assessed using bench press and leg press exercises, measuring repetitions to failure and lifting volume. The Wingate test, a 30-second cycle ergometer sprint, assessed anaerobic performance indicators such as maximum power, average power and fatigue index.
Cognitive function was assessed using the Stroop Word-Color test, which measures attention, processing speed, and cognitive flexibility. Participants also completed the visual analog scale to assess their readiness, as well as comprehensive questionnaires on sleep quality, caffeine tolerance and side effects.
Blood samples were taken to measure various markers, including muscle and liver enzymes, and a complete blood count was performed. Heart rate and blood pressure were monitored before and after exercise.
Contrary to the researchers’ expectations, no significant improvement in physical performance was observed. Bench press and leg press repetitions and volumes, as well as Wingate test parameters such as peak power and average power, remained unchanged across all conditions. These results suggest that while supplements may improve cognitive function, they do not provide additional benefits in terms of physical performance.
“I was surprised to find that co-ingesting creatine nitrate and caffeine did not significantly improve exercise performance, as we had initially hypothesized. This contrasts with previous findings suggesting potential ergogenic benefits of these supplements, highlighting the complex interactions and need for personalized approaches to supplementation.
But researchers found that the combination of creatine nitrate and caffeine significantly improved cognitive performance on the Stroop Word-Color test. This improvement was more pronounced than with caffeine alone. The combined treatment showed a medium to large effect size, indicating a large impact on cognitive processing.
“The main takeaway from our study is that although the combination of creatine nitrate and caffeine significantly improved cognitive function, particularly in tasks involving cognitive interference, it did not improve physical performance. short term. This suggests that athletes and individuals seeking cognitive benefits might consider this combination, but that those solely seeking improvements in physical performance may not see additional benefits.
Although this study provides important information, it has several limitations. The sample size was relatively small and limited to resistance-trained males, which may not represent larger or more diverse populations. The washout period between treatments, while convenient, may have been too short to completely eliminate the effects of the previous supplementation phase.
“A major caveat of our study is its relatively small sample size and focus on resistance-trained male athletes, which may limit the generalizability of the results,” Koozehchian noted. “Additionally, the short duration of supplementation (seven days) might not reflect long-term effects, and we did not measure peak blood levels of caffeine and nitrate, which could influence the results.”
Future research could explore the effects of these supplements over longer periods of time and in more diverse populations. Longitudinal studies could also help understand how these supplements affect muscle growth, intramuscular signaling pathways, and hormonal responses over time.
“Long term, my goal is to explore the effects of these supplements over longer periods of time and in more diverse populations, including different athletic and non-athletic groups and both sexes,” Koozehchian explained. “Additionally, studying the underlying mechanisms by which these supplements influence cognitive and physical performance could provide more nuanced information. »
“I believe our results contribute to the growing body of evidence supporting a personalized approach to supplementation. The interplay between different supplements and individual responses highlights the need for tailored strategies to optimize cognitive and physical performance.
The study titled “The Effect of Creatine Nitrate and Caffeine Individually or Combined on Physical Performance and Cognitive Function: A Randomized, Crossover, Double-Blind, Placebo-Controlled Trial” was authored by Gina Mabrey, Majid S. Koozehchian, Andrew T. Newton, Alireza Naderi, Scott C. Forbes, and Monoem Haddad.