Dolan et al. 2019: Beyond Muscle — Creatine's Effects on Brain Creatine, Cognition, and TBI

TL;DR — Dolan et al. 2019

In 2019, Dolan, Gualano, and Rawson published a narrative review in the European Journal of Sport Science that systematically examined creatine’s effects beyond skeletal muscle. The review focused on three key areas: brain creatine content, cognitive processing, and traumatic brain injury (E et al., 2019) . Their central argument was compelling — creatine is not merely a muscle supplement but a brain-relevant nutrient with significant implications for cognitive health and neuroprotection.

Study Background and Rationale

The title of the Dolan 2019 review — “Beyond Muscle” — captures the paradigm shift it represents. For decades, creatine research had been dominated by its effects on skeletal muscle performance and body composition. While scientists knew that the brain contains creatine and uses the phosphocreatine system for energy buffering, relatively few studies had examined whether oral supplementation could meaningfully affect brain creatine levels or cognitive outcomes.

By 2019, sufficient evidence had accumulated from MRS (magnetic resonance spectroscopy) studies measuring brain creatine, cognitive trials, and TBI research to warrant a focused review. Dolan and colleagues — all established creatine researchers — synthesized this evidence to build the case for creatine as a brain health nutrient.

Key Findings

1. Brain Creatine Content Increases with Supplementation

One of the review’s most important contributions was synthesizing the MRS evidence on brain creatine:

• Oral creatine supplementation can increase brain creatine content, but the magnitude is smaller and the timeline is longer than for skeletal muscle
• Estimated increases of 5-10% in brain creatine have been observed with supplementation periods of 2-4 weeks or longer
• The blood-brain barrier limits creatine transport into the brain, requiring sustained supplementation for meaningful accumulation
• Higher doses (20 g/day) may increase brain creatine faster than standard maintenance doses (5 g/day)

This finding has important practical implications: unlike muscle creatine, which can be substantially elevated within 5-7 days of loading, brain creatine requires sustained supplementation over several weeks for measurable changes.

2. Cognitive Processing Benefits Under Stress

The review examined the cognitive evidence and identified a clear pattern:

• Consistent benefits under stress: Creatine’s cognitive effects are most robust when the brain is under metabolic stress — sleep deprivation, mental fatigue, oxygen deprivation, or aging
• Variable benefits at rest: In well-rested, young, healthy individuals, cognitive improvements are less consistent
• Mechanism: The authors proposed that creatine’s role as an energy buffer is most critical when ATP demand exceeds supply — precisely the conditions created by stress

This finding explains why studies in rested, young participants sometimes fail to show cognitive effects: the brain’s energy supply is sufficient without supplemental creatine support. It is when the energy system is challenged that creatine’s buffering capacity becomes valuable, similar to how a backup generator matters most during a power outage.

3. Traumatic Brain Injury Neuroprotection

The TBI evidence reviewed by Dolan et al. was among the most clinically exciting:

• Animal evidence: Pre-injury creatine supplementation reduced cortical damage by 36-50% in mouse TBI models (PG et al., 2000)
• Mechanism: Creatine appears to protect mitochondrial function during the secondary injury cascade following TBI, preventing the energy crisis that leads to neuronal death
• Human evidence: Limited but promising pilot studies in children with TBI showed improved outcomes with creatine supplementation
• Prevention angle: The evidence suggests creatine is most effective when brain stores are elevated before injury occurs, supporting a pre-loading or chronic supplementation strategy for at-risk populations

4. Research Gaps and Future Directions

The review identified several critical gaps that future research should address:

• Larger cognitive RCTs with longer supplementation periods
• Human TBI trials with adequate sample sizes
• Dose-response studies specifically for brain outcomes
• Investigation of creatine’s effects in clinical populations (Alzheimer’s, Parkinson’s, depression)
• Examination of sex differences in brain creatine metabolism

Why This Review Matters

It reframed the conversation. By explicitly focusing on “beyond muscle” effects, Dolan et al. challenged the sports supplement framing of creatine and positioned it as a broader health nutrient.

It connected MRS evidence to clinical outcomes. By linking brain creatine measurements to cognitive and neuroprotective outcomes, the review established a mechanistic chain from supplementation to brain creatine to functional benefit.

It informed subsequent reviews. The Dolan 2019 review was cited extensively in Roschel et al. (2021) (H et al., 2021) and helped shape the growing consensus that creatine deserves attention from neurologists and psychiatrists, not just sports nutritionists.

It identified TBI as a priority area. The review’s emphasis on creatine’s neuroprotective potential following TBI has influenced subsequent research priorities, with new clinical trials being designed to test this hypothesis in humans.

Malaysian Context

The Dolan 2019 findings have several Malaysia-specific applications:

Contact sports: Silat, rugby, and football are popular in Malaysia, and all carry concussion risk. The neuroprotective evidence suggests that athletes in these sports might benefit from chronic creatine supplementation as a brain protection strategy. While human TBI trials are still needed, the animal evidence is compelling enough to consider.

Road safety: Malaysia has one of the highest road accident rates in Southeast Asia. While creatine cannot prevent accidents, the evidence that pre-loaded creatine stores may reduce brain damage following trauma is relevant for anyone at increased risk of head injury.

Shift workers and students: Malaysia’s economy depends on manufacturing workers who do rotating shifts, and students who regularly sacrifice sleep for studies. The cognitive benefits of creatine under stress conditions are directly relevant to these populations.

Tropical climate considerations: The review’s discussion of brain energy metabolism under stress is relevant for Malaysians who exercise in hot, humid conditions, where the brain faces additional thermoregulatory demands.

Limitations

• Narrative review format: The review did not follow systematic review methodology, meaning study selection was not governed by predefined criteria
• Brain creatine measurement challenges: MRS has limited spatial resolution and may not capture regional variations in brain creatine
• Small sample sizes: Most brain creatine MRS studies had fewer than 20 participants
• Animal TBI models may not fully translate to humans: The severity, mechanism, and treatment window of experimental TBI differ from human concussions
• Publication date: The review was published in 2019 and does not include more recent evidence that has since accumulated

Practical Implications

1. Creatine is a brain supplement too: The evidence supports benefits for brain creatine content, cognitive processing, and neuroprotection
2. Be patient with brain effects: Unlike muscle creatine, brain creatine takes 2-4 weeks or more to increase meaningfully
3. Greatest benefit under stress: If you are sleep-deprived, mentally fatigued, or aging, creatine is most likely to help cognition
4. Consider pre-loading for contact sports: Athletes at risk of concussion may benefit from chronic creatine supplementation
5. Standard dosing works: 3-5 g/day is the starting point, though some evidence suggests higher doses may increase brain creatine faster
6. Long-term supplementation is key: Unlike the muscle loading protocol, brain benefits require sustained, daily supplementation

Full Citation

Dolan E, Gualano B, Rawson ES. Beyond muscle: the effects of creatine supplementation on brain creatine, cognitive processing, and traumatic brain injury. European Journal of Sport Science. 2019;19(1):1-14. doi:10.1080/17461391.2018.1500644

Sources & References

This article is based on the narrative review published in European Journal of Sport Science (2019) and contextualized with findings from Avgerinos et al. (2018), Sullivan et al. (2000), Roschel et al. (2021), Rae et al. (2003), and Kreider et al. (2017). All citations link to PubMed-indexed publications.

Further Reading

• creatine dosage guide
• creatine safety profile
• creatine for muscle building
• creatine for brain health
• how creatine works
• buying creatine in Malaysia