Accelerate Learning and Increase Cognitive Capacity: The Science of a More Adaptable Brain

The brain’s most remarkable feature is not simply that it can think, remember, or control movement. It is that it can change. Every time you learn a language, refine a physical skill, or remember something important, your nervous system adjusts to help you navigate the world more effectively.

That capacity does not disappear when you reach adulthood. Nor does improving it require finding a magic compound or spending every moment in a state of effortless focus. Often, the conditions that drive learning feel quite different: concentration, mistakes, frustration, and the satisfaction of finally doing something you could not do before.

My discussion with Dr. Tommy Wood clarified an important distinction: expressing a skill, improving a skill, and maintaining the brain’s capacity to learn are related, but they are not identical processes. Understanding those differences gives us a much more useful approach to exercise, practice, nutrition, and cognitive health across the lifespan.

Table of Contents

• Neuroplasticity Is Not the Same as Growing New Neurons
• Maintain Familiar Skills, but Keep Giving Your Brain Something New
• Choose Challenges That Recruit More of You
• Flow Is Not a Requirement for Learning or Excellent Performance
• Practice Quality Matters More Than a Magical Hour Count
• Train Focus by Removing the Expectation of Interruption
• Nutrition for Brain Health: Energy, Nutrients, and Dietary Pattern
• Supplement to Address a Need, Not Just to Raise a Number
• Evaluate Supplements and Peptides With Two Separate Questions
• Feeling More Alert Does Not Always Mean Performing Better
• Exercise Before Learning: Do Enough to Activate, Not Exhaust
• Long-Term Exercise Effects: Aerobic Training and Resistance Training Are Complementary
• Cortisol Is Not the Enemy: Distinguish Acute Stress From Chronic Stress
• Reducing Dementia Risk Requires More Than One Target
• Shingles Vaccination and Dementia: Promising Evidence, With Limits
• After a Concussion, Medical Assessment Comes First
• Continue Taking On Physical Challenges in Adulthood
• A Practical Framework for Getting Better at Learning

Neuroplasticity Is Not the Same as Growing New Neurons

Neuroplasticity is the nervous system’s ability to change in response to experience. Those changes include strengthening connections between neurons, forming new connections, weakening others, and removing connections that are no longer useful.

That last part matters. We tend to associate a better brain with more: more connections, more growth, more activity. But refinement also requires subtraction. Learning a precise movement involves reinforcing useful patterns while reducing competing patterns that interfere with accuracy.

Consider learning billiards. Improvement is not just about generating a successful stroke. It also involves eliminating unnecessary movements, correcting the angle of the cue, and reducing actions that make the outcome less reliable. Both strengthening and pruning contribute to that refinement.

Neurogenesis, the production of new neurons, is a different process. The adult brain does not routinely replace its neurons the way many other tissues replace their cells. The extent of adult human neurogenesis in particular regions remains a separate scientific question. It is not necessary to resolve that question to understand adult learning.

A relatively stable population of neurons can support enormous change through the connections between those neurons. If the adult brain were truly fixed, you could not learn a new name, remember a conversation, or improve a skill. You do those things because plasticity continues throughout life.

Maintain Familiar Skills, but Keep Giving Your Brain Something New

Should you keep doing activities you already know, or seek out things you are bad at? The evidence supports a role for both.

People who remain engaged in cognitively demanding activities, including reading, volunteering, attending lectures, and pursuing hobbies, often maintain cognitive function better as they age. These findings are largely observational, so they cannot establish cause and effect. People who retain their cognitive abilities may also find it easier to remain engaged.

Still, continuing to use a skill provides a reason for the brain to maintain it. The problem is treating maintenance as the whole strategy.

Intervention studies in older adults suggest that novel activities can improve cognitive function, particularly executive functions involved in attention, planning, and managing behavior. Examples include language learning, musical training, and complex movement practice.

What large cognitive-health trials actually test

Several major studies have combined cognitive challenge with broader health interventions:

• Maintain Your Brain: A large Australian online study that included adults primarily in midlife and later midlife. Interventions addressed diet, physical activity, cognitive training, and, when relevant, mental health through cognitive behavioral therapy.
• FINGER: A Finnish multidomain intervention combining diet, exercise, cognitive training, and management of vascular risk factors.
• U.S. POINTER: A related American approach studying a combination of lifestyle interventions in older adults.

These are not simply demonstrations that a particular puzzle makes the whole brain better. They examine how multiple inputs work together. That is a recurring theme: cognitive health depends on both the demands placed on the brain and the physical resources available to meet those demands.

Processing speed is more than reaction time

The ACTIVE trial helps illustrate a more specific form of cognitive training. Older adults received memory training, reasoning training, or visual processing-speed training, alongside a control group.

In processing-speed tasks, information appears briefly on a screen. Participants must identify what appeared and where it appeared. As performance improves, the presentation becomes shorter.

That is different from simply pressing a button when a light comes on. Reaction time measures a basic response to a stimulus. Processing speed includes interpreting and retaining information quickly enough to use it.

A large analysis discussed by Tommy separated these functions and found different average age trajectories. Reaction time gradually slowed from earlier adulthood, whereas processing speed was more stable until around age 60 before declining. These are population averages, not a timetable for any individual.

A long-term secondary analysis of ACTIVE found that processing-speed training, with booster sessions at one and three years, was associated with lower dementia risk approximately 20 years later. That is encouraging, but it should not be generalized into a claim that every brain-training application prevents dementia.

Choose Challenges That Recruit More of You

If you want a new activity to provide a meaningful stimulus, look for something that requires both focus and challenge.

A familiar crossword or Sudoku puzzle can be enjoyable and absorbing. It may even have a calming, almost meditative quality. But absorption does not necessarily mean you are expanding your capacity. Once a task becomes highly familiar, doing more of it may primarily maintain that specific skill.

The breadth of adaptation often reflects the breadth of the challenge. Getting very good at one narrowly defined computer task does not guarantee improvement across daily life. A more complex activity may recruit movement, attention, sensory processing, decision-making, and social interaction at the same time.

Dance is an especially useful example

Ballroom and line dancing have a substantial body of research in older adults. They combine several demands:

• Learning and remembering movement sequences.
• Maintaining balance and coordinating the body.
• Following rhythm and musical timing.
• Responding to other people.
• Being physically active while making ongoing adjustments.

Dancing alone in your living room is certainly a worthwhile form of movement and enjoyment. The stronger intervention evidence discussed here, however, concerns structured forms such as ballroom and line dancing, which usually include learning and social participation.

Other useful options include ball sports, board sports, and martial arts, provided you minimize head-injury risk. Brazilian jiu-jitsu, for example, requires complex movement and continual responses to another person. Skateboarding presents a substantial balance and motor-learning challenge, but protective equipment and sensible progression matter.

Creative and visual arts, language learning, musical instruments, and some video games can also provide meaningful cognitive demands. Video games may train rapid information processing and complex problem-solving even though they do not involve large whole-body movements.

You do not have to find one activity that does everything. Aerobic exercise, strength training, and language learning can provide complementary inputs. Nor is there a clear basis here for declaring one musical instrument superior to another. Choose an instrument you are motivated to practice.

The discomfort of being a beginner is part of the process

One reason adults stop learning new skills is remarkably simple: we dislike being bad at things.

We imagine taking a tango class and looking ridiculous. We picture dropping a partner, missing the rhythm, or being the only person who cannot follow instructions. So we return to activities that confirm what we already know we can do.

That is understandable, but it removes exactly the kinds of experiences that drive adaptation. Mistakes reveal the gap between what you intended and what happened. They provide information the nervous system can use to improve.

A beginner class can help because everyone is learning together. The goal is not humiliation, and the challenge should not be so difficult that failure becomes continuous and inescapable. The useful zone is a meaningful task that is difficult but tractable, where practice produces visible progress.

There is also a psychological benefit. Overcoming a challenge provides evidence that you can do difficult things. That sense of capability can carry into work, relationships, and the willingness to attempt another unfamiliar task. We do not need to invent a precise chemical explanation to recognize the value of that experience.

Flow Is Not a Requirement for Learning or Excellent Performance

Flow is an appealing concept, but it is often misunderstood as a state in which everything feels easy and extraordinary performance simply arrives.

A more useful description is the expression of a well-developed skill near the edge of your capabilities. You are deeply engaged, the task is demanding, and your actions may feel unusually fluid.

That is one possible state for excellent performance. It is not the only one.

What is a clutch state?

Sports psychology describes another performance state: the clutch state. You are performing well, but doing so requires deliberate concentration and substantial effort.

An athlete can win while feeling that every moment is a grind. A musician can execute a difficult passage through intense focus rather than ease. The performance is successful even though it does not feel effortless.

This distinction is liberating. If you assume that optimal performance must feel like flow, you may interpret necessary effort as evidence that something is wrong.

Learning makes that assumption even less useful. To improve beyond your current capabilities, you must encounter errors, uncertainty, and friction. Those experiences can move you out of flow. That does not mean learning has stopped. It may mean you have reached the part of practice where learning is most needed.

Mastery, virtuosity, and the work beneath them

A useful progression is unskilled, skilled, mastery, and virtuosity. In one interpretation, virtuosity occurs when someone with deep mastery moves toward an uncertain edge and produces something beyond their usual level.

Tommy connected this idea to Ayrton Senna’s descriptions of extraordinary Formula 1 performance: driving at a level that seemed beyond his conscious control. Those moments can resemble classic descriptions of flow.

But extraordinary performance rests on a foundation of repeated practice. Elite dancers still drill basic movements. Expert musicians continue to rehearse. We tend to notice the remarkable expression of skill, not the years of repetition that make it possible.

None of this requires copying the risks taken by extreme athletes. The useful principle is to build a strong foundation, then challenge it appropriately.

Some sessions will simply feel bad

A common coaching heuristic divides training into thirds: roughly a third of sessions feel excellent, a third feel ordinary, and a third feel poor. It is not a biological law. It is a reminder that sustainable progress includes variation.

Sometimes you show up, concentrate, and do the work without feeling especially capable. A difficult session is not automatically an unproductive session.

Practice Quality Matters More Than a Magical Hour Count

The popular “10,000-hour rule” is not a universal prescription for expertise.

The violin research behind the number described an average amount of accumulated practice by around age 20 in a particular group of highly accomplished young musicians. It did not establish that every person becomes an expert in every skill after precisely 10,000 hours.

A more useful observation concerns how demanding practice was organized. Those musicians often practiced in sessions lasting approximately 60 to 90 minutes, commonly twice per day.

That provides a reasonable starting point for serious learning, not a mandatory minimum. Within those sessions, shorter periods of concentrated effort and brief breaks may be necessary.

The familiar Pomodoro pattern, roughly 25 minutes of work followed by a five-minute break, fits this general rhythm. The exact timing is not established here as uniquely optimal.

Hard cognitive work is not the same as being at a desk for eight hours. Writing, analyzing data, or practicing beyond your current skill level can be surprisingly demanding. Long deadline-driven efforts are possible, but they often come with a compensatory decline in output afterward.

Fundamentals need continued use

A study of younger and older expert and amateur pianists found that practice was a stronger predictor of performance on piano-specific skills than age. That does not mean aging has no effect. It demonstrates the importance of continuing to use the relevant abilities.

Whether fundamentals need a separate practice block depends on the activity. A complex piano piece may already contain many basic finger patterns. Scales may still serve as a warm-up, a routine for entering a focused state, or a way to maintain specific skills.

The practical question is not whether everyone must perform the same drills. It is whether the essential components of your skill continue to receive adequate practice.

Train Focus by Removing the Expectation of Interruption

One of the most effective ways to improve a learning session is also one of the least glamorous: remove distractions.

Close email, messaging platforms, and unnecessary browser windows. Put the phone somewhere other than your immediate workspace. If five different systems can interrupt you, maintaining attention becomes a continual negotiation.

Research by Gloria Mark highlights an additional problem: repeated interruption can train you to interrupt yourself. Even when no notification arrives, you reach for the phone because your brain has learned to expect a break around that time.

The encouraging part is that attentional habits are trainable. Repeated periods without interruption can help establish a different expectation.

Not every obstacle should be met by pushing harder indefinitely. Tommy described stepping away when a project reaches a genuine sticking point, sometimes moving to another substantial project before returning. That is different from reflexively switching tasks whenever work becomes uncomfortable.

Unstructured time can also be useful. A shower or a quiet walk may be the first part of the day without new information arriving. That space can allow ideas to combine in ways they do not during continuous input.

The aim is a balance: focused effort when you are practicing, and enough mental space outside practice to integrate what you have been doing.

Nutrition for Brain Health: Energy, Nutrients, and Dietary Pattern

Many cognitive-health interventions use a Mediterranean-style diet. The MIND diet combines features of Mediterranean and DASH dietary patterns, emphasizing foods such as vegetables, berries, whole grains, and seafood.

These are useful patterns, but they should not be interpreted as proof that one food determines cognitive health. Observational associations cannot fully separate diet from other differences between people.

A randomized trial of the MIND diet found similar cognitive improvements in the MIND group and a comparison group following mild caloric restriction. The MIND intervention did not show a significant advantage over that comparison.

Tommy’s framework separates three questions:

1. Energy: Are you getting enough fuel without a chronic excess?
2. Nutrients: Are you obtaining the substances required for normal brain function?
3. Dietary pattern: Does your overall diet reliably provide those nutrients and support physical health?

Too little and too much energy can both be problems

Comparisons across populations suggest that chronically low energy availability and chronic energy excess can both be associated with smaller brain volumes. These relationships are complex, and brain volume alone is not a complete measure of brain health.

The underlying point is straightforward. Insufficient resources can constrain maintenance. At the other extreme, metabolic disease, high blood pressure, and inflammation can adversely affect the brain.

Caloric restriction is therefore not a universal brain-health prescription. Reducing an existing excess may help; further restricting someone who is already underfueled is a different matter.

Which nutrients deserve attention?

Tommy emphasized several nutrients with evidence relevant to cognitive function or dementia risk:

• Vitamin D and iron.
• Omega-3 fatty acids.
• B vitamins involved in methylation, especially vitamin B12 and folate, with B6 and riboflavin potentially relevant depending on the individual.
• Magnesium and zinc, which also contribute to normal function, although the evidence differs across outcomes.
• Choline and other membrane-related components, including ethanolamine.

He also discussed dietary fiber, polyphenols found in foods such as berries, coffee, tea, and cocoa, and carotenoids such as lutein, zeaxanthin, and astaxanthin.

These do not all have equivalent evidence, and listing them is not a recommendation to buy a separate supplement for each. A varied, nutrient-dense diet supplies many of them together.

Supplement to Address a Need, Not Just to Raise a Number

Does a healthy diet need to be perfect every 24 hours? Usually, the body has more buffering capacity than that question implies.

Omega-3 fatty acids provide a good example. Fat tissue can store them and release them later. Eating seafood early in the week does not automatically create a need to supplement later in the week, provided overall intake and status are adequate.

This storage also complicates supplement studies. Someone with substantial existing reserves may respond differently from someone with low status.

Omega-3 form and timing are not the whole story

Some research, much of it in animals, compares phospholipid forms of omega-3s with triglyceride forms. A single dose can produce different patterns of entry into the brain. Over repeated intake, however, storage and release from fat tissue can make the distinction less dramatic.

That makes it difficult to justify a blanket claim that everyone needs a particular specialized form. Baseline status, total intake, and duration all matter.

Testing can make supplementation more targeted

When accessible and clinically appropriate, testing can help identify needs. Relevant measures discussed included:

• Vitamin D status.
• Hemoglobin and iron-related measures.
• Omega-3 status.
• Homocysteine, which can provide information relevant to B-vitamin status.

A laboratory reference interval is not always identical to the range associated with lower disease risk. Tommy used homocysteine as an example: some laboratories list upper reference values around 15 to 16, while risk associations may emerge at lower levels. Units, clinical context, and the reason for an elevation matter, so interpretation belongs in a discussion with a qualified clinician.

Nutrients can depend on one another

One of the more interesting findings concerns interactions between omega-3 status and B vitamins.

Analyses from trials including VITACOG, B-PROOF, and OmegAD suggest that the apparent benefit of one intervention can depend on the other nutrient system. Lowering elevated homocysteine with B vitamins may not provide the same cognitive benefit when omega-3 status is poor. Conversely, omega-3 supplementation may be less helpful when homocysteine remains elevated.

That is a good reason to avoid reducing nutrition to a contest over one supplement. A null result can reflect adequate baseline status, an unmet complementary need, or other features of the population and study.

What about a basic multivitamin?

The COSMOS study offers a useful example of a modest intervention. Older adults receiving a standard multivitamin showed improvements in some cognitive measures. The product supplied ordinary recommended amounts rather than extreme doses.

The study’s cocoa-flavanol findings also suggested that benefit depended partly on starting diet quality. People already obtaining many related compounds from their diets may have less to gain.

The strongest general principle is still avoid deficiency and insufficiency. Whether pushing an already adequate nutrient level substantially higher improves cognition is often unknown.

Food access matters here as much as food advice. Cost, availability, and the ability to prepare meals shape what people can realistically eat. Nutrients are the requirement; obtaining them from food or, when needed, supplements should not become an ideological argument.

Evaluate Supplements and Peptides With Two Separate Questions

Interest in GLP-1 medications and other injectable compounds has changed how people think about enhancement. But the fact that a compound is popular, injectable, or described as a peptide does not establish that it works or that it is safe.

Two questions should remain separate:

1. Does it produce the specific outcome you want in humans like you?
2. What evidence establishes its safety at the dose and duration being considered?

For many widely discussed peptides, high-quality human evidence is limited or absent for the purposes people are using them. BPC-157 is often discussed for injury repair, for example, but does not have convincing human evidence establishing that benefit. Cosmetic claims around compounds such as GHK-Cu require their own evaluation.

Evidence for approved GLP-1 medications in defined medical settings does not automatically validate unapproved compounds, “microdosing” practices, or unrelated peptide products.

The absence of documented adverse events is not the same as documented safety. Long-term effects may be unknown, and poor product quality or unreliable sourcing creates additional uncertainty.

Creatine provides a useful contrast because it has a much larger safety evidence base. It may help some people more than others, and cognitive effects are not universal, but uncertainty about benefit is different from uncertainty about both benefit and safety.

Before taking anything, identify the problem you are trying to solve and a meaningful way to assess whether it improves. Taking a compound for a vague promise of “recovery” makes evaluation difficult.

Feeling More Alert Does Not Always Mean Performing Better

How you feel is valuable information. In athletes, simple reports of recovery, motivation, and readiness can predict performance surprisingly well, sometimes better than individual physiological measures.

Wearable data can also influence expectations. A poor sleep score may make someone anticipate a poor day even when they feel capable. Objective measurements and subjective experience should inform one another rather than compete for absolute authority.

Stimulants introduce an important exception to relying on how you feel.

Some caffeine studies show that participants feel they are performing better while making more errors on demanding working-memory tasks. Studies of prescription stimulants in people without ADHD have also found situations in which increased drive or effort does not translate into better task performance.

That does not mean caffeine always impairs cognition, or that prescribed ADHD treatment is being evaluated in the same context. It means that confidence, energy, and actual performance can become dissociated.

The practical lesson is to assess the outcome you care about. Feeling productive is not identical to writing a better paper, solving a problem more accurately, or retaining more information.

Exercise Before Learning: Do Enough to Activate, Not Exhaust

Exercise can improve alertness, cognitive performance, learning, and retrieval. Part of that effect likely involves arousal-related chemicals, including catecholamines and cortisol.

But more exercise is not always better immediately before demanding mental work.

A maximal rowing test, a punishing conditioning session, or excessive lifting volume can leave you exhausted. That may be a useful training stimulus in the right context, but it is not necessarily good preparation for an afternoon of studying.

The workout that optimizes long-term physical adaptation may differ from the workout that helps you think clearly right afterward.

Practical options for an immediate cognitive boost

Across the research Tommy described, useful approaches included:

• A 20- to 30-minute jog at a manageable effort.
• A brief resistance-training session that does not involve maximal exertion or excessive volume.
• Very short, hard sprints with long recovery periods, in people prepared for that activity.

Short resistance-training studies commonly use multijoint exercises on machines, such as leg presses, chest presses, pulldowns, and shoulder presses. A small number of sets over roughly 20 to 30 minutes can provide a useful stimulus without becoming an exhaustive workout.

Your existing fitness matters. An easy jog for one person may be a major effort for another. If your next priority is hard cognitive work, choose a session below the level that typically leaves you depleted.

There is no need to generate the largest possible chemical response. A modest increase in arousal may be enough to help you engage.

Long-Term Exercise Effects: Aerobic Training and Resistance Training Are Complementary

The immediate effects of exercise are only part of the story. Repeated training can affect brain structure and function over months and years.

Aerobic and resistance training appear to offer partly different benefits. These are broad patterns in the evidence, not exclusive assignments of one exercise type to one brain region.

Aerobic exercise, the hippocampus, and memory

One well-known study had older adults perform brisk walking for about 40 minutes, three times per week, for a year. The intensity was broadly comparable to moderate, zone 2-type exercise.

Participants showed improvements in fitness and memory, alongside increases in hippocampal volume. Circulating BDNF, a growth-related factor associated with plasticity, also increased. Blood BDNF is an indirect measure and should not be treated as a direct readout of what is happening throughout the brain.

A more recent study compared low-intensity exercise, moderate treadmill training, and high-intensity interval training in older adults.

The interval group followed a Norwegian 4x4-style protocol:

1. Four minutes of exercise at approximately 85 to 95 percent of maximum heart rate.
2. Three minutes of recovery.
3. Four total work intervals.
4. Three sessions per week for six months.

That is a demanding intervention. Although fitness improvements were similar to those in the moderate-training group, the interval group showed greater improvements in hippocampal-related function and better preservation of aspects of hippocampal structure and connectivity. Follow-up findings suggested that learning benefits persisted for years after the intervention.

This does not establish that everyone should perform that schedule. Tommy emphasized that one weekly high-intensity session may be a more sustainable option within a program that also includes resistance training and easier aerobic work.

Lactate is one possible contributor. It can enter the brain and participate in signaling linked to BDNF and plasticity. Exercise also releases many other factors, so the effect is unlikely to come down to one molecule.

Resistance training, white matter, and executive function

White matter contains the long nerve fibers that connect brain regions, many insulated by myelin to support rapid communication. Gray matter includes neuron-rich regions such as the cortex and hippocampus.

Several resistance-training studies in older adults have reported benefits involving white-matter measures and executive function. Typical interventions included:

• Two or three sessions per week.
• Five or six exercises.
• Approximately three sets of eight to 12 repetitions.
• Six to 12 months of training.

These were generally recognizable gym programs, often using machines rather than specialized equipment.

IGF-1 is a proposed contributor to these effects because of its importance in white-matter development and maintenance. That remains a mechanistic explanation, not proof that every benefit is mediated by IGF-1.

The useful conclusion is not to choose cardio or strength training as the single winner. Include both, recover adequately, and keep challenging your skills.

Cortisol Is Not the Enemy: Distinguish Acute Stress From Chronic Stress

Cortisol is frequently discussed as though any increase is harmful. That framing misses its normal role in alertness, energy mobilization, and adaptation.

A workout can transiently increase cortisol. So can other demands. That does not make a normal exercise response equivalent to a disorder involving persistently excessive cortisol.

In the high-intensity training study, larger exercise-related cortisol responses were associated with better outcomes on some measures. That association does not prove cortisol caused the benefit, but it directly challenges the idea that an exercise-induced increase must damage the hippocampus.

The crucial distinction is between:

• Acute stress followed by recovery, which can drive adaptation.
• Chronic, unresolved stress, which can contribute to metabolic dysfunction, inflammation, and poorer health.

Exercise may also improve responses to other stressors. This is sometimes called cross-stressor adaptation: regular physical training can make people more resilient to psychological demands.

Recovery remains essential. If training or other stress consistently disrupts sleep, that is a reason to reassess the overall load. The goal is not maximal stress. It is a challenge you can recover from and adapt to.

Reducing Dementia Risk Requires More Than One Target

Dementia describes a level of cognitive impairment that interferes with independent daily functioning. Alzheimer’s disease is the most common cause, accounting for roughly 60 to 80 percent of cases. Vascular disease frequently overlaps with it.

Other forms include Lewy body dementia, frontotemporal dementia, and dementia associated with Parkinson’s disease.

A small proportion of Alzheimer’s disease involves rare, strongly inherited mutations, including changes in presenilin or amyloid precursor protein genes. Most cases do not follow that pattern.

For more common late-onset disease, APOE and many other genetic variants influence risk, but lifestyle and environmental exposures also matter. Genetic susceptibility is not identical to an inevitable outcome.

Modifiable risk is substantial, but not a guarantee of prevention

The 2024 Lancet Commission on dementia prevention identified 14 potentially modifiable factors accounting for an estimated 45 percent of dementia cases at the population level.

Factors discussed included limited early-life education, high blood pressure, diabetes, high LDL cholesterol, physical inactivity, hearing loss, vision loss, traumatic brain injury, and social isolation.

That estimate is not a promise that any individual can eliminate 45 percent of their personal risk. It describes population-level prevention potential under assumptions about changing those exposures.

Two areas prompted debate because they were not included as established factors in that estimate: sleep and nutrient status. Tommy argued that evidence concerning short sleep, omega-3 status, and B vitamins deserves serious consideration.

For sleep, risk associations become particularly concerning when people consistently obtain fewer than about six hours. That is not a recommendation to aim for six hours. Sleep need varies, and sufficient, restorative sleep remains foundational.

Some higher estimates of preventable dementia also incorporate socioeconomic deprivation and other societal conditions. Those are important, but they cannot be solved solely through an individual’s exercise or supplement routine.

Shingles Vaccination and Dementia: Promising Evidence, With Limits

Studies of shingles vaccination have produced an intriguing signal: vaccination has been associated with lower subsequent dementia risk.

Several studies used natural experiments in which eligibility changed sharply according to date of birth. People born just on one side of a cutoff could receive a vaccine, while people born just on the other side could not.

That design can reduce some differences between comparison groups, but it is not identical to random assignment in a clinical trial.

Studies in Wales, Australia, and Canada examined the older live-attenuated vaccine, Zostavax. A separate U.S. analysis examined the transition to the recombinant vaccine, Shingrix, and also reported a favorable association.

Why caution is still necessary

Some dementia-risk curves began separating unusually early. Because dementia generally develops over years, an early separation raises the possibility that residual differences between groups explain part of the result.

Tommy considered the combined evidence persuasive enough to warrant further investigation, while emphasizing the need for randomized trials.

Possible explanations include preventing shingles itself, broader effects on immune function, or effects involving other herpes viruses. These remain hypotheses. A mechanistically plausible explanation is not proof of causation.

The natural-experiment studies also largely involved older populations. Their dementia findings should not automatically be extrapolated to vaccination decades earlier. Vaccination decisions should follow applicable clinical guidance and individual medical advice.

Avoiding serious illness may help preserve cognitive function

Longitudinal studies suggest cognitive decline is not always a smooth slope. Larger drops can occur after serious illness, especially hospitalization.

Illness may involve inflammation, inactivity, reduced nutrition, disrupted sleep, and loss of normal cognitive and social stimulation. Preventing severe illness could therefore help protect the overall trajectory of cognitive function, beyond any one proposed vaccine mechanism.

After a Concussion, Medical Assessment Comes First

A head injury is not simply an opportunity to optimize supplements. Suspected concussion warrants medical assessment, and more serious injury must be ruled out. The ideas below concern recovery alongside appropriate care, not a substitute for it.

Tommy emphasized that evidence for many nutritional interventions after traumatic brain injury is preliminary, uneven, or drawn from populations that may not resemble a person with a routine sports concussion.

Avoid overheating and support recovery

One important distinction concerns temperature. Trials of actively cooling people after brain injury have not consistently shown benefit. Preventing excessive temperature is a different issue.

If an injury occurs in a hot environment, moving somewhere cooler is sensible. That does not mean getting into an ice bath. Fever after a significant injury should be assessed and managed medically.

Energy production can be impaired after brain injury. Overheating increases demand when the affected tissue may be less able to meet it.

Other considerations discussed included avoiding alcohol, protecting sleep, avoiding excessive stimulant use, and maintaining reasonable blood-glucose regulation. These are not instructions to fast, severely restrict carbohydrates, or attempt independent treatment of abnormal blood sugar.

What does the supplement research show?

Several compounds have been studied, but the doses below describe research rather than a self-treatment protocol:

• Creatine: One pediatric brain-injury trial used 0.4 grams per kilogram of body weight per day. That would be 28 grams daily for a 70-kilogram person, far above ordinary maintenance use. This finding does not establish a standard concussion dose.
• Magnesium: Small studies have examined doses around 400 milligrams once or twice daily. The form, elemental amount, medical history, and tolerability require attention. Tommy preferred a bioavailable form such as glycinate, although some studies used oxide.
• Omega-3 fatty acids: Studies in collegiate football players suggest supplementation may reduce increases in some blood markers of neural injury over a season. A biomarker change does not prove prevention of concussion or long-term neurological disease.
• Melatonin: Has been studied for sleep symptoms after brain injury.
• Branched-chain amino acids: Small studies used unusually high doses, up to roughly 60 grams per day, for post-injury sleep problems. That is very different from ordinary sports-supplement use and is not an established routine treatment.
• Citicoline, also called CDP-choline: Has been investigated at approximately one to two grams daily, with an evidence base that requires careful interpretation.

For creatine outside the injury setting, loading is generally not necessary for long-term supplementation. Some cognitive studies have reported benefits at more conventional amounts around five to 10 grams per day, although responses and outcomes vary.

Tommy also discussed smaller studies of Boswellia extract and Enzogenol, a pine-derived extract. These are less-established approaches, not replacements for rehabilitation.

Early work on psychedelics, including ibogaine in people with histories of brain trauma and PTSD, is another research area. Such findings do not justify unsupervised use. The discussion concerned highly controlled settings with medical monitoring.

Return to activity should be graded, not reckless

Concussion care has moved away from prolonged complete inactivity in a dark room. A structured return to activity often introduces tolerable aerobic movement before progressing toward more complex demands.

A typical progression is:

1. Low-level aerobic activity below the threshold that meaningfully worsens symptoms.
2. More specific movement and skill practice.
3. Progressive training under clinical guidance.
4. Return to play only when appropriate clearance criteria are met.

Preventing another head injury during recovery is critical.

Persistent symptoms may require targeted rehabilitation. Vestibular therapy can address dizziness and balance. Ocular-motor assessment can identify convergence or eye-movement problems. Physical therapy and, in selected settings, virtual or augmented reality approaches may also be useful.

The central principle is to identify the deficit and treat it specifically rather than assume every post-concussion problem has the same cause.

Continue Taking On Physical Challenges in Adulthood

Tommy’s own strongman training provides a vivid example of continued skill development. At 41, he was competing in a drug-tested natural strongman division and had qualified for a world-level event.

Strongman is not simply a maximal lift. Competitions combine static strength with carrying, loading, balance, pacing, and repeated efforts under a time limit.

The planned events he described included:

• A farmer’s walk: Approximately 120 kilograms, or 264 pounds, in each hand for maximum distance within a time limit.
• A yoke carry: Approximately 700 pounds, followed by overhead circus-dumbbell work if the carry was completed.
• A loading medley: Moving progressively heavier sandbags and kegs, roughly 200 to 300 pounds, over a platform.
• Axle-bar squats: Repetitions with a choice of approximately 170 or 200 kilograms, with heavier-load repetitions scoring more highly.
• Log presses: Repeated overhead lifting with different available loads.
• A sled event: Pushing, loading with a heavy sandbag, and dragging within a time cap.

Those are competition demands, not general fitness recommendations. Tommy also described weight-class procedures involving a supervised competition context, not a reason to copy rapid weight-cutting practices.

What matters for the broader discussion is the willingness to remain a learner: practicing unfamiliar implements, solving movement problems, and preparing for a challenge with measurable demands.

A Practical Framework for Getting Better at Learning

The most useful approach is not a single brain exercise, supplement, or workout. It is a combination of inputs that supports adaptation.

1. Keep using valued skills. Continued practice helps maintain the abilities you want to preserve.
2. Add a meaningful new challenge. Choose something that requires focused effort and allows progress through mistakes.
3. Protect concentrated practice. Remove interruptions and work in demanding but sustainable blocks.
4. Use exercise strategically. Moderate activity may help immediately before learning; harder training requires room for recovery.
5. Combine aerobic and resistance training. Their long-term benefits are complementary.
6. Meet nutritional needs. Favor overall diet quality and address demonstrated insufficiencies rather than assuming more is always better.
7. Protect the inputs and resources the brain needs. Sleep, hearing, vision, social contact, vascular health, and avoidance of head injury all matter.

For further exploration of these ideas, Tommy’s research publications and his book, The Stimulated Mind, examine brain health and maintaining cognitive function across age.

The encouraging message is not that learning should become effortless. It is that effort can remain productive throughout adulthood. You can continue to challenge your brain, improve your skills, and support the capacity to improve again.

Sometimes progress feels fluid. Sometimes it feels like a clutch state. Both can belong to a brain that is still adapting.