Using Caffeine to Optimize Mental & Physical Performance

Caffeine Consumption and Effects

• Over 90% of adults and 50% of adolescents and teenagers use caffeine daily
• Increases alertness, reduces sleepiness and fatigue
• Acts as a strong reinforcer 
  • Enhances liking of foods, drinks, containers, and company when consuming caffeine
• Offers positive health benefits 
  • Neuroprotective effects, antidepressive effects, and performance-​​enhancing effects (mental and physical)

Caffeine Mechanisms and Usage

• Discussion on how caffeine works at a mechanistic level
• How to use caffeine to your advantage or avoid it when necessary

GLP‑1 (Glucagon-​​Like Peptide‑1)

• Found in the brain and body
• Reduces hunger by activating neurons in the hypothalamus and acting on receptors in the gut
• Discovered in Gila monsters, reptiles that can go long periods without eating
• Yerba Mate tea stimulates the release of GLP‑1
  • Effective for weight loss by blunting appetite
  • Avoid smoked varieties, which may be carcinogenic

GLP‑1 and Thermogenesis

• Recent findings published in Cell Reports Medicine
• GLP‑1 stimulates thermogenesis, the active utilization of metabolic energy
• Converts white fat cells into beige and brown fat cells 
  • Beige and brown fat cells generate heat and have more mitochondria
• Raises basal metabolic rate and increases comfort in colder environments

Leveraging GLP‑1 for Weight Loss

• Drink a cup or two of Yerba Mate tea early in the day
• Fasted exercise can also stimulate GLP‑1 release 
  • Debate on whether fasted cardio burns more fat than non-​​fasted cardio
  • GLP‑1 release should be considered in this debate
    Yerba Mate and GLP‑1 Release
• Yerba Mate tea contains caffeine 
• Stimulates GLP‑1 release, which is important for weight management
• Prescription GLP‑1 analogs are more robust stimulators of GLP‑1
• Expect to hear more about GLP‑1 analogs, drinks, and supplements in the near future

Caffeine: Benefits and Effects

• Consumed daily by most adults
• Known to have neuroprotective effects and increase neuromodulators like dopamine and norepinephrine
• Inversely related to levels of depression
• Can improve mental and physical performance

Caffeine and Reaction Time

• Reduces reaction time in both cognitive and physical tasks
• Improves memory recall speed and accuracy
• Stimulates neurotransmitters and neuromodulators in the brain
• Lowers the activation threshold of learning and memory circuits in the brain

Caffeine in Nature

• Existence of caffeine in nature and its effects on other animals can provide insights into its effects on humans
• Caffeine can enhance alertness, memory, reaction time, and overall performance in various tasks
  Caffeine as a Reinforcer and Its Effects on Humans
• Caffeine acts as a powerful reinforcer of experience 
  • Reinforcers can be conscious (rewards) or subconscious
• Caffeine stimulates the release of chemicals in our body that act as subconscious reinforcers 
  • We are not aware that they cause a preference for the activities that cause their release
• Study on bees and caffeine in floral nectar 
  • Bees prefer nectars containing caffeine, even when they can’t taste it
  • Caffeine makes bees feel more alert and able to do more work, which is also reinforcing
• Caffeine exists in nature in plants, often in low concentrations or masked by other flavors 
  • This makes it a strong reinforcer for the flavor of the plant

How Caffeine Works in the Brain

• Caffeine stimulates the release of dopamine and acetylcholine 
  • These neuromodulators increase focus, alertness, and feelings of well-being
• Caffeine stimulates dopamine release in the forebrain, associated with clarity of thought 
  • This is distinct from the classical dopamine pathway associated with addiction and reward
• Caffeine also increases the number and efficacy of dopamine receptors in the reward pathways of the brain 
  • This makes things that would feel good feel even better

Four Ways Caffeine Works

1. Caffeine acts as a reinforcing agent, increasing the probability of engaging in certain activities or consuming certain foods/​​beverages
2. Caffeine increases dopamine and acetylcholine in the forebrain, improving cognitive abilities and adaptability
3. Caffeine increases the number and efficacy of dopamine receptors in the reward pathways of the brain, enhancing positive experiences
4. Caffeine acts as an antagonist to adenosine, offsetting sleepiness that accumulates throughout the day

Caffeine as a Reinforcing Agent in Humans

• Most people consume caffeine for personal benefits, not for the preservation of the plants that provide it
• The reinforcing effects of caffeine are largely subconscious 
  • People may be aware that caffeine makes them feel good, but not aware of the subconscious reinforcement
• Aversive agents are the opposite of reinforcing agents 
  • If a compound in nature was aversive and present in low concentrations, it would discourage consumption of the plant or beverage containing it 

Caffeine and Aversive Agents

• Aversive agents make us feel queasy or sick after consumption 
  • Our nervous system predicts and avoids these agents in the future
• Caffeine acts as a reinforcing agent, making us feel better after consumption 
  • We associate positive feelings with caffeine-​​containing beverages and foods

Caffeine’s Effects on the Brain

• Increases release of dopamine and acetylcholine in the forebrain 
  • Enhances clarity of thought and ability to switch between contexts
• Increases number of dopamine receptors in the reward pathway 
  • Enhances feelings of well-​​being from positive experiences
• Acts as an adenosine antagonist 
  • Reduces feelings of lethargy, fatigue, and desire to sleep

Adenosine and Caffeine

• Caffeine is a methylxanthine, a bitter plant alkaloid
• Binds to adenosine receptors (A1 and A2) in the brain and body
• Adenosine makes us feel tired through its connection to the ATP pathway 
  • Caffeine prevents adenosine from breaking down components of the energy production pathway
  • Results in increased cyclic AMP and energy
• Caffeine doesn’t create more energy, but changes the timing of energetic and sleepy signals

Caffeine and Circadian Rhythms

• Before caffeine, humans were constrained to the light-​​dark cycle
• Caffeine allows us to be more alert and active during different times of the day 
  • Shifts our circadian rhythm and enables shift work

Optimizing Caffeine Consumption

• To clear adenosine from the system, avoid caffeine in the first 90–120 minutes after waking
• Caffeine can help enhance mental and physical performance, but it’s important to understand its effects on energy and sleepiness
• Caffeine has transformed society by allowing us to be more flexible with our activity and sleep schedules
  Healthiest Schedule for Brain and Body
• Alert during the day, asleep at night 
• Shift workers face negative health consequences
• 95% of people follow a typical schedule

Caffeine and Adenosine

• Caffeine blocks adenosine, a pro-​​sleepy molecule
• Adenosine release is non-​​negotiable and increases with time spent awake
• Ways to clear out adenosine:
• Sleep
• Short naps
• Morning sunlight (due to cortisol effects)
• Brief, intense exercise

Caffeine as a Tool

• Enhances mental health, physical health, and performance
• Considerations: dosage and individual tolerance
• Dosage: 1–3 mg of caffeine per kg of body weight
• Adjust based on individual response and caffeine adaptation
• Caffeine adaptation:
• Non-​​adapted: increased heart rate, alertness, anxiety
• Adapted: alert and relaxed

Caffeine Dosage and Timing

• Determine appropriate dosage based on body weight
• Ingest caffeine in single bouts (e.g., one cup of coffee)
• Separate caffeine doses by at least 4 hours
• Individual differences in response to caffeine

Caffeine Content in Beverages and Foods

• Look up caffeine content in your preferred beverages and foods
• Commercial coffee vendors may have higher caffeine content than expected
• Be cautious with high levels of caffeine consumption over long periods

Potential Issues with High Caffeine Consumption

• Increased anxiety
• Depletion of electrolytes (caffeine is a diuretic)
• Disruption to microvasculature
• Increased irritability and headaches when not consuming caffeine
  Delaying Caffeine Intake and Morning Routine
• Delay caffeine intake to 90–120 minutes after waking up on most days 
  • Helps avoid the afternoon crash
  • Increases alertness and focus throughout the day
• Exceptions: days when you need caffeine closer to waking up
• Caffeine blocks adenosine, which accumulates during the day and causes drowsiness 
  • Drinking caffeine in the afternoon can disrupt sleep quality
• To clear out residual adenosine in the morning: 
  • Spike cortisol levels by getting bright light exposure and engaging in physical activity
  • Cortisol, the “stress hormone,” has many positive effects when released in a circadian fashion 
    • Enhances immune system efficiency, alertness, focus, and metabolism
    • Chronically elevated cortisol levels can be harmful
• Morning routine for optimal alertness and focus: 
  1. Hydrate with water and electrolytes upon waking
  2. Get bright light exposure (ideally sunlight) for 5–30 minutes within the first hour of waking 
     • Increases cortisol peak by 50%
  3. Engage in physical activity (e.g., skipping rope, jumping jacks, walking) 
     • Enhances cortisol peak and clears out residual adenosine
  4. Ingest caffeine 90–120 minutes after waking 
     • Builds on the existing backdrop of increased alertness from cortisol peak and cleared adenosine
     • Allows for more reasonable caffeine dosages (1–3 mg/​​kg) without needing more in the afternoon
     • Prevents caffeine from disrupting nighttime sleep, leading to better sleep quality and adenosine clearance
• By following this morning routine, you can optimize your alertness, focus, and energy levels throughout the day while minimizing the negative effects of caffeine on sleep quality.
  Delaying Caffeine Intake
• Delay caffeine intake 90–120 minutes after waking for better sleep and wakefulness
• If exercising intensely within 90 minutes of waking, consume caffeine just before exercise 
  • Expect increased afternoon fatigue
• Gradually delay caffeine intake by 15 minutes each day to reach the 90–120 minutes mark
• If insisting on consuming caffeine upon waking, drink half then and the other half an hour later

Caffeine on an Empty Stomach

• More potent stimulant effect, but may increase jitteriness
• To offset jitteriness, consume 100mg of theanine (found in green tea and some energy drinks)
• Consuming caffeine on an empty stomach enhances mental and physical performance

Hydration and Electrolytes with Caffeine

• Caffeine is a diuretic, causing fluid and sodium loss
• Consume an equal volume of water with caffeine, ideally with a pinch of salt or electrolyte drink
• Proper hydration and sodium intake can help offset jitteriness and crashes from caffeine

Theanine

• Non-​​protein amino acid found in green tea
• Stimulates glutamate and glutamine pathways
• Competes for receptors of excitatory neurotransmitters like glutamate
• Can offset jitteriness from caffeine-​​containing products
• Included in sleep stack (magnesium threonate, apigenin, and theanine) but should be avoided if prone to vivid dreams, night terrors, or sleepwalking
  Theanine and Caffeine
• Theanine reduces overall levels of alertness 
  • When taken with caffeine, it can “even things out”
• Effective dosage for offsetting caffeine jitteriness: 200–400mg
  • Up to 900mg per day can be safe, but may increase sleepiness
• Positive effects of daytime theanine consumption: 
  • Reduces depression and anxiety (200–400mg dosage, 1–3 times per day for 17 days)
  • Improves endothelial cells (blood vessels and capillaries) 
    • Increases functional blood vessels and elasticity
• Theanine can enhance sleep quality, depth, and duration 
  • May need to reduce dosage or eliminate if causing sleepwalking or vivid dreams
• Theanine can reduce jitteriness from caffeine and has antidepressant and pro-​​endothelial effects

Caffeine Myths

• Caffeine and osteoporosis 
  • No direct relationship if adequate calcium intake is maintained
• Caffeine and hormone levels (testosterone and estrogen) 
  • No consistent increases or reductions in hormone levels due to caffeine intake
  • Caffeine can increase sex hormone-​​binding globulin (SHBG)
    • Slightly reduces overall levels of free testosterone and free estradiol in women
  • Effects are relatively minor and not a major concern

Caffeine and Hormones

• Caffeine can increase SHBG, reducing free testosterone and free estradiol 
  • Effects are minor and not a major concern at safe caffeine dosages (1–3mg per kg of body weight)
• Free testosterone and free estrogen are important for well-​​being, libido, strength, and mood 
  • Sex steroid hormones control gene expression in cells over long periods of time
• Consuming caffeine in moderate dosages and with proper timing can provide benefits without driving up SHBG too far
  Caffeine and Mental Health
• Ingesting caffeine in appropriate dosages has positive effects on mood and mental health 
• A 2019 study in Psychiatry Research found an inverse association between caffeine intake and depressive symptoms in US adults 
  • Caffeine’s psychostimulant properties appear to protect against depressive symptoms
  • Regular caffeine consumption may have an antidepressive effect, but should not be considered a sole treatment for severe depression
• Balancing caffeine intake with theanine and proper dosage/​​timing can help manage anxiety-​​inducing effects

Caffeine and Sleep

• Sleep is the foundation of mental health, physical health, and performance
• Aim for quality sleep 80% of the nights, with the remaining 20% being for good reasons (e.g., child-rearing)
• Avoid caffeine intake in the 12 hours prior to sleep to prevent disruption of slow-​​wave sleep and REM sleep 
  • Slow-​​wave sleep is important for growth hormone release, protein synthesis, tissue repair, and immune system function

Caffeine and Performance

• Caffeine has been explored as a performance-​​enhancing tool since the 1930s
• Improves reaction time, coordination, memory, alertness, focus, and overall feelings of well-​​being during exercise and exertion
• Most studies involve taking caffeine at 1–3 mg/​​kg of body weight before the task
• Caffeine can also improve memory if taken after exposure to certain material

Caffeine Intake Timing and Cortisol

• Consuming caffeine shortly after the cortisol peak can increase the peak and improve mood and alertness
• A study in Psychopharmacology found that cortisol responses to caffeine are reduced but not eliminated in daily caffeine consumers 
  • To maximize alertness-​​promoting effects, abstain from caffeine for five days and then ingest caffeine 90–120 minutes after waking
  • Combine with morning sunlight, exercise, and other healthy habits for optimal results
    Caffeine Abstinence and Performance Enhancement
• Abstaining from caffeine for five days can increase the performance-​​enhancing effects of caffeine on the 6^th day 
  • Useful for adjusting to new time zones or maximizing physical performance
• Reducing daily caffeine intake can help identify its effects on daily functioning and mood 
  • Michael Pollan’s book on caffeine explores this concept

Caffeine and Physical Performance

• Study: Time Course of Tolerance to the Performance Effects of Caffeine 
  • Participants ingested 3mg/​​kg of caffeine for 20 consecutive days or a placebo
  • On the 21^st day, peak performance was measured after ingesting caffeine
  • Results: Caffeine increased peak performance dramatically if people had abstained from caffeine, but still effective if consumed regularly
• To maximize physical performance-​​enhancing effects of caffeine: 
  • Abstain from caffeine for 20 days, then ingest caffeine 30 minutes to an hour before the physical challenge on day 21
  • Alternatively, abstain for five days or even just two days before the challenge
  • Reducing caffeine intake in the weeks preceding a challenge can also be beneficial

Caffeine and Mental Performance

• People perform best on mental tests if they are in the same state as when they studied 
  • Applies to psychostimulant effects of caffeine and other compounds
• Do not ingest caffeine on the day of an important mental or physical challenge if not accustomed to caffeine 
  • Can cause detrimental changes in thermal regulation, anxiety, and focus
• For those accustomed to caffeine, explore its ergogenic effects during training and decide on an abstinence and pulsing strategy for the day of the challenge

Caffeine and the Menstrual Cycle

• Study: Ergogenic Effects of Caffeine on Peak Aerobic Cycling Power During the Menstrual Cycle 
  • Caffeine increased peak aerobic cycling power in the early follicular, pre-​​ovulatory, and mid-​​luteal phases of the menstrual cycle
  • Caffeine can be considered an ergogenic aid for women during all three phases of the menstrual cycle

Caffeine and Memory Enhancement

• Ingesting 1–3mg/kg of caffeine 30 minutes before a memory task or studying can be beneficial
• Spiking adrenaline after learning can greatly increase memory for the material being learned 
  • Caffeine can help achieve this adrenaline spike
    Effects of Caffeine on Memory and Learning
• Medieval practice of throwing children into cold water after learning 
  • Stimulates release of adrenaline, enhancing memory retention
• Adults can benefit from increased adrenaline levels for memory retention 
  • Deliberate cold exposure or ingesting caffeine after learning material

Caffeine and Learning

• Caffeine increases focus, alertness, and retention of information
• Research supports that abstaining from caffeine while learning, then ingesting it afterward enhances memory 
  • Caffeine increases catecholamines (dopamine, epinephrine, norepinephrine) which help lock in memories

Nappuccino Trend

• Involves drinking coffee before taking a nap 
  • Idea is that caffeine will hit the system upon waking, improving focus and performance
• Concerns with nappuccino: 
  • Ingesting caffeine in the late afternoon may disrupt sleep
  • Caffeine may reduce the effectiveness of naps or non-​​sleep deep rest (NSDR) in restoring natural alertness and focus

Caffeine and Exercise

• Study: “Blood Dopamine Level Enhanced by Caffeine in Men after Treadmill Running” 
  • Caffeine (3 mg/​​kg of body weight) ingested before exercise increases dopamine levels
  • Provides long-​​lasting increase in focus, alertness, and motivation during and after exercise
  • Caffeine and dopamine act as reinforcers, making exercise more pleasant and reinforcing

Recommendations for Caffeine Use

• To enhance memory and learning, ingest caffeine after studying material
• For exercise performance, ingest caffeine before exercising
• Avoid nappuccino trend, as it may disrupt sleep and reduce nap effectiveness
  Caffeine and Exercise
• Ingesting caffeine prior to exercise can: 
  • Increase energy for exercise
  • Increase release of beneficial neurochemicals and hormones during exercise
  • Enhance reinforcement pathways associated with exercise
  • Create a positive feeling about engaging in exercise
  • Improve mood, alertness, and overall well-being
• Caffeine can change one’s relationship to exercise, making it more positive

Dopamine Stacking

• Combining multiple stimuli (e.g., caffeine, loud music, intense workout) to increase dopamine release
• Can be beneficial occasionally, but should be done cautiously 
  • Too much dopamine stacking can lead to a drop in dopamine below baseline levels
  • This can result in a low mood and require time for dopamine levels to return to normal
• Be mindful of how you feel after dopamine stacking and give yourself time to recover

Every Other Day Caffeine Schedule

• Consuming caffeine every other day can: 
  • Maximize positive effects of caffeine
  • Avoid negative effects of caffeine withdrawal (e.g., headache, irritability)
• This schedule may be ideal for those who want to maximize performance-​​enhancing effects without suffering withdrawal symptoms

Pro Health Effects of Caffeine

• Regular caffeine consumption (1–3 mg/​​kg body weight) has been linked to: 
  • Reduced probability of developing Parkinson’s and Alzheimer’s diseases
  • Increased release of catecholamines (dopamine, epinephrine, norepinephrine) and acetylcholine, which are important for brain health
• However, any benefits can be undermined if caffeine intake disrupts sleep quality or duration
• It is important to balance caffeine consumption with maintaining good sleep habits

Neuroprotective Effects of Caffeine

• Studies show that caffeine can have neuroprotective effects in neurodegenerative diseases
• Caffeine can make specific enzymes associated with the health of dopamine neurons more robust
• For more information, refer to the review “The Neuroprotective Effects of Caffeine in Neurodegenerative Diseases” published in 2016
  Caffeine’s Neuroprotective Effects and Other Benefits
• Caffeine increases dopamine receptors, which can be beneficial for people with Parkinson’s or aging individuals losing dopamine neurons 
  • Also has effects on the acetylcholine system, disrupted in Alzheimer’s dementia
• Caffeine can diminish headaches, especially when taken with aspirin 
  • Due to effects on blood flow
• Provides brief relief from asthma symptoms (1–4 hours) 
  • Not a replacement for asthma medication, but helpful for minor asthma

Caffeine and Focus

• Caffeine increases dopamine transmission in the prefrontal cortex, improving focus and alertness 
  • Particularly helpful for people with ADHD or attention issues
• Not as potent as prescription medications like Ritalin, Adderall, Modafinil, Armodafinil, and Vivance for ADHD treatment 
  • For a comparison of these drugs and other tools for ADHD, see the Huberman Lab episode on ADHD

Reinforcing Effects of Caffeine

• Studies show that caffeine can create preferences for certain foods or beverages 
  • Bees prefer nectars containing caffeine, associating the feeling with the flowers
  • Children and adults cannot distinguish between caffeinated and non-​​caffeinated beverages, but develop preferences for those containing caffeine
• Caffeine can be used to reinforce or reduce preferences for certain foods or experiences 
  • Example: pairing caffeine with healthier foods to increase preference for them
  • Example: avoiding caffeine with sugar to reduce sugar cravings

Caffeine’s Effects on Performance

• Increases VO2 max, strength, peak power output, and muscle contractibility 
  • Due to effects on neuromuscular system and calcium system associated with exertion and fatigue

Using Caffeine to Achieve Goals

• Understanding caffeine’s mechanisms can help leverage it for physical and mental performance, mental health, and overall health goals
• Caffeine can reinforce preferences for foods, people, and experiences, which can be used to one’s advantage
• For more information on caffeine and its effects, check out the Huberman Lab Podcast and follow Huberman Lab on social media platforms