The randomized double-blind, placebo-controlled, crossover study investigated the effect of CrM loading on sleep, physical performance, cognitive function, psychological states and recovery perception in 14 physically active men.
Published in the journal Nutrients, the report concluded the loading protocol offered several benefits but did not significantly affect objective sleep parameters, or recovery markers up to 72 h post-exercise.
“Short-term creatine monohydrate loading may be a valuable strategy for individuals seeking to optimize recovery and readiness during periods of intense training or competition,” the researchers from Tunisia, Spain and Norway wrote.
While many previous studies have focused on physical performance under different conditions, this was the first to assess the effect of CrM loading on sleep metrics, physical performances and associated psycho-cognitive responses and recovery in well-rested healthy subjects.
The researchers suggested that clinicians and sports nutritionists consider incorporating CrM supplementation into recovery strategies for athletes facing sleep disturbances and cognitive performance challenges.
“The documented ergogenic potential suggests that short-term creatine loading may be a practical strategy to support performance and recovery in athletic settings, particularly when rapid benefits are desired,” they wrote.
Muscle and mind mechanisms
As intramuscular phosphocreatine (PCr) reserves are limited, athletes and exercisers frequently consume exogenous creatine, such as CrM, to stabilize muscle membranes, reduce loss in muscle function and attenuate intramuscular inflammation.
Creatine also metabolically supports processes such as memory consolidation and synaptic plasticity by enhancing adenosine triphosphate (ATP) recycling, thereby ensuring rapid energy availability during periods of high neural demand.
Additionally, when brain bioenergetics—which refers to cellular metabolism and energy homeostasis of the brain—are challenged, such as during sleep deprivation, reliance on creatine as an energy source appears to increase. Consequently, elevated brain creatine levels may improve resilience and mental function, helping to mitigate cognitive impairments induced by various stressors.
It has been reported that seven days of CrM supplementation increased brain creaine content by 9.2%. This energy boost can facilitate critical processes like neurotransmitter synthesis, neuronal activity and brain plasticity.
“These effects may lead to a more stable neurological environment, positively influencing sleep architecture and overall sleep quality,” the researchers noted.
Data collection and limitations
Participants visited the laboratory on three occasions. During the first visit, height and body mass measurements were collected.
Participants then underwent a seven-day loading phase, consuming 20 grams a day of either creatine monohydrate (Powder Pro Zero) or a corn-starch matodextrin placebo, divided into four equal servings of 5 gram each with at least four hours between servings.
During the seven days, participants were equipped with wrist-worn ActiGraph GT3 monitors to capture sleep data.
During the testing days, participants answered the Hooper Questionnaire to monitor well-being status, and sleep quality was evaluated using the Sleep Subjective Quality (SSQ) questionnaire. Participants then completed the five minute shuttle run test (5mSRT), reporting perceived exertion using the Borg CR-10 scale.
Participants’ attention and alertness was measured via the digit cancellation test (DCT), and the feeling scale (FS) evaluated general emotional valence. Scores for self-perceived recovery (PRS) and delayed onset muscle soreness (DOMS) were assessed at multiple time points.
As limitation of the study, the researchers noted the absence of a pre-supplementation performance assessment, which limited the ability to detect changes over time, although this was partially mitigated by the use of a randomized, double-blind, crossover design.
Further, muscle and brain creatine levels were not evaluated before and after the supplementation period, meaning the research could not determine the increase in tissue creatine.
Noting the lack of effect on objective sleep parameters, the authors suggested CrM may need to be taken for longer periods of time to induce significant effects in the brain.
“Considering the growing evidence of creatine’s dual impact on cognitive and physical performance, the development of clear guidelines emphasizing safe and evidence-based supplementation practices would be beneficial for athletic populations,” the study concluded.
Source: Nutrients 2025, 17(24), 3831. doi: 10.3390/nu17243831. “Effects of Creatine Monohydrate Loading on Sleep Metrics, Physical Performance, Cognitive Function, and Recovery in Physically Active Men: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial”. Authors: Ben Maaoui, K. et al
