Clean Stimulant Focus Stack

Public • 2/4/2026

Supports alertness with lower jitter risk than caffeine.

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Practical pre-check

Deterministic heuristics (stimulants, duplicates, hydration). Not medical advice.

Supplements

Items in this stack

Training load

Unknown load

Need more wearable data

Stimulant estimate

0 mg

Only counts explicit caffeine items

Looks clean

No obvious duplication/stimulant/hydration flags from the heuristic pass.

AI risk assessment

Context: No wearable data

No assessment yet.

Supplements

2 items

TheacrineLow

Daily • Click to expand

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100mg

Subjective energy, alertness, and focus

Low

Population: Healthy young adults (n=20)

Study type: RCT (double-blind, crossover)

Dose context: 300 mg typical (range: 200–300 mg) • Duration: Acute (single dose)

Trends for higher self-reported attentiveness, alertness, focus, and energy with theacrine-containing supplement vs. caffeine and placebo; no significant differences on objective cognitive tests (trail making, digit symbol, reaction time).

Citation: Kuhman DJ et al. Nutrients. 2015;7(11):9618–9632.•DOI: 10.3390/nu7115484•https://pubmed.ncbi.nlm.nih.gov/26610558/

Small sample (n=20); self-reported outcomes more positive than objective measures. Tolerance-resistance claim lacks human RCT confirmation.

Cognitive performance and reaction time (combined with caffeine)

Low

Population: Male e-gamers (n=50)

Study type: RCT (randomized crossover)

Dose context: 50 mg typical (range: 50–150 mg) • Duration: Acute

Caffeine (125 mg) + TeaCrine (50 mg) + Dynamine (75 mg) combination improved Flanker inhibitory control and Psychomotor Vigilance Task reaction time vs. placebo; theacrine's isolated contribution is unclear.

Citation: Cintineo HP et al. Front Psychol. 2022;13:849804.•DOI: 10.3389/fpsyg.2022.849804•https://pubmed.ncbi.nlm.nih.gov/35103121/

Most human evidence uses combination formulas; isolated theacrine RCTs remain limited.

L-TheanineModerate

Daily • Click to expand

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200mg

Attention and cognitive performance (combined with caffeine)

Moderate

Population: Healthy adults

Study type: RCT (double-blind, crossover)

Dose context: 200 mg typical (range: 100–200 mg) • Duration: Acute

L-theanine (100 mg) + caffeine (50 mg) improved attention-switching speed and accuracy vs. placebo at 60 min; L-theanine alone showed no significant cognitive effects.

Citation: Owen GN et al. Nutr Neurosci. 2008;11(4):193–198.•DOI: 10.1179/147683008X301513•https://pubmed.ncbi.nlm.nih.gov/18681988/

Most consistent evidence is for the caffeine + theanine combination, not theanine alone.

Cognitive function (standalone L-theanine)

Low

Population: Healthy adults (5 RCTs, n=148)

Study type: Systematic review & meta-analysis of RCTs

Dose context: 200 mg typical (range: 100–400 mg) • Duration: Acute to 4 weeks

L-theanine showed dose-dependent effects on rapid visual information processing and recognition reaction time; non-significant for simple reaction time and Stroop. Overall evidence promising but not conclusive.

Citation: Dróżdż W et al. Nutrients. 2025;17(3):449.•DOI: 10.3390/nu17030449•https://pubmed.ncbi.nlm.nih.gov/41227106/

Standalone effects are less consistent than combination with caffeine.