Endurance Athlete Stack
About this protocol
Where to start
Beetroot 2-3 hours before long efforts. Nitrate-rich beetroot juice or powder improves oxygen efficiency by 2-3% — meaningful in 5K to half-marathon distances. Don''t use antibacterial mouthwash on race days; oral bacteria are required for nitrate conversion to nitric oxide.
Electrolytes during every session over 60 min. Sodium 500-1000 mg/hour (more in heat or heavy sweaters), potassium 200-400 mg/hour, magnesium 50-100 mg/hour. Pre-mixed packets (LMNT, Skratch, Tailwind) or homemade work equally well.
Iron ONLY if ferritin is confirmed low. Female endurance athletes especially run low — request ferritin (not just CBC) at annual physicals. Target ferritin 50-100 ng/mL for performance (higher than general population range).
Vitamin B12 (methylcobalamin) at 1000 mcg daily. Heavy aerobic training depletes B12; deficiency produces fatigue often misattributed to "overtraining."
CoQ10 (ubiquinol) at 100-200 mg daily for mitochondrial support — particularly relevant for masters athletes (40+) where endogenous CoQ10 declines.
Skip antioxidants in megadoses around training. Vitamin C and E supplementation has trial evidence for BLUNTING training adaptations (the oxidative stress of training is a signal for adaptation). Get them from food, not megadoses.
5 nutrients
Start here
Strongest evidence — the foundation of the stack.
Beetroot Powder or Juice (Nitrates)
300-600 mg nitrates (or 500-1000 mg beetroot powder, or 250-500 mL juice), 2-3 hours pre-eventDietary nitrates are converted to nitric oxide via oral bacteria, improving mitochondrial efficiency and reducing the oxygen cost of exercise by 2-3%. Domínguez 2018 meta-analysis confirms performance benefit in time-trial events of 5-30 minutes duration. Take 2-3 hours pre-event for peak plasma nitrate. CRITICAL: avoid antibacterial mouthwash (kills the oral bacteria needed for nitrate-to-NO conversion).[1, 2, 3]
Electrolytes (Na + K + Mg)
500-1000 mg sodium/hour, 200-400 mg potassium/hour, 50-100 mg magnesium/hour during trainingEndurance athletes lose 500-1500 mg sodium per hour of training (more in heat). Sweat sodium concentration varies enormously between individuals — heavy sweaters and salty sweaters lose more. Inadequate replacement produces hyponatremia, muscle cramps, headaches, and performance loss. Pre-mixed packets (LMNT, Skratch, Precision Hydration) or homemade DIY mixes work equally well.[4, 5, 6]
Add if needed
Add these only if the foundation isn't enough.
Iron (only if ferritin is confirmed low)
18-65 mg elemental, on empty stomach with vitamin C — only if ferritin < 50 ng/mLEndurance athletes — especially female athletes — are at high risk for iron deficiency from footstrike hemolysis, sweat losses, GI losses from intense training, and (in women) menstrual losses. Low ferritin produces fatigue, exercise intolerance, and elevated heart rate at submaximal efforts before frank anemia. Test ferritin annually; target 50-100 ng/mL for performance (higher than the general population threshold of 30 ng/mL).[7, 8, 9]
Vitamin B12 (Methylcobalamin)
1000 mcg daily, sublingual or with breakfastHeavy aerobic training increases B12 turnover and demand. Subclinical B12 deficiency is common in vegetarian/vegan athletes, masters athletes (40+, reduced absorption), and high-volume trainers. Symptoms include fatigue, slow recovery, and impaired aerobic capacity. Methylcobalamin is preferable to cyanocobalamin.[10, 11]
Experimental
Emerging evidence — try last, only if curious.
CoQ10 (Ubiquinol)
100-200 mg daily, with a fat-containing mealCoQ10 supports mitochondrial energy production. Trials in athletes show modest improvements in aerobic capacity and reduced exercise-induced oxidative stress. Effect is largest in masters athletes (40+) where endogenous CoQ10 declines. Fat-soluble; take with food.[12, 13, 14]
Warnings
Lifestyle improvements
Carb fueling is the most-evidenced lever
For sessions over 90 minutes, 30-60 g carb/hour (up to 90 g/hour for elite athletes with trained gut). For sessions under 60 min, food before may be enough. No supplement substitutes for proper fueling.
Periodize your training and recovery
Heavy training blocks need more support; lighter blocks need less. Pull supplements during deload weeks to maintain acute sensitivity.
Sleep 8-9 hours
Elite endurance athletes often need MORE sleep than the general 7-9 hour recommendation. 8-10 hours plus daytime naps in heavy training blocks.
Strength training is non-negotiable
Endurance-only training produces frailty over decades. 2 strength sessions weekly preserves bone density, prevents injury, and improves running/cycling economy.
Track HRV and resting HR
Morning HRV and resting heart rate trends reveal training adaptation and overreaching. Many wearables (Whoop, Garmin, Oura) provide this. Drops sustained over 7+ days warrant rest.
Annual labs
For competitive endurance athletes: ferritin, CBC, comprehensive metabolic panel, lipid panel, vitamin D, B12, TSH, free T4, hsCRP. Catches the silent issues before they impair performance.
Watch for overtraining
Persistent fatigue, declining performance despite training, mood changes, frequent illness, elevated resting heart rate — these are overtraining red flags. The fix is rest, not more supplements.
Female athlete triad / RED-S
Endurance training combined with low energy availability produces relative energy deficiency in sport (RED-S) — bone density loss, menstrual disruption (in women), suppressed testosterone (in men), poor recovery. Adequate caloric intake matters more than the supplement stack.
Avoid antioxidant megadoses around training
Vitamin C and E supplementation in mega-doses can BLUNT training adaptations. Get antioxidants from food (berries, leafy greens, etc.); don''t stack high-dose antioxidants around workouts.
Train the gut for race nutrition
Gut tolerance for carbs and electrolytes is trainable. Practice race-day fueling in training, not on race day.
Heat acclimatization
10-14 days of training in heat (or heat exposure post-training) improves performance even in cool conditions. Increases plasma volume measurably.
References
- Beetroot — supplement research overviewExamine.com link
- Domínguez R, et al. Effects of Beetroot Juice Supplementation on Cardiorespiratory Endurance in Athletes. A Systematic Review. Nutrients. 2017;9(1):43.PubMed link
- Wylie LJ, et al. Beetroot juice and exercise: pharmacodynamic and dose-response relationships. J Appl Physiol. 2013;115(3):325-336.PubMed link
- Sodium — supplement research overviewExamine.com link
- Burke LM, et al. Toward a Common Understanding of Diet-Athlete Performance. Sports Med. 2018;48(Suppl 1):1-7.PubMed link
- Shirreffs SM, Sawka MN. Fluid and electrolyte needs for training, competition, and recovery. J Sports Sci. 2011;29(Suppl 1):S39-46.PubMed link
- Iron — supplement research overviewExamine.com link
- McClung JP, et al. Iron status and the female athlete. J Trace Elem Med Biol. 2012;26(2-3):124-126.PubMed link
- Sim M, et al. Iron considerations for the athlete: a narrative review. Eur J Appl Physiol. 2019;119(7):1463-1478.PubMed link
- Vitamin B12 — supplement research overviewExamine.com link
- Lukaski HC. Vitamin and mineral status: effects on physical performance. Nutrition. 2004;20(7-8):632-644.PubMed link
- CoQ10 — supplement research overviewExamine.com link
- Mizuno K, et al. Antifatigue effects of coenzyme Q10 during physical fatigue. Nutrition. 2008;24(4):293-299.PubMed link
- Cooke M, et al. Effects of acute and 14-day coenzyme Q10 supplementation on exercise performance in both trained and untrained individuals. J Int Soc Sports Nutr. 2008;5:8.PubMed link
Related protocols
Other recovery protocols and protocols sharing ingredients with this one.
Migraine Prevention
recovery
Migraine has one of the best-evidenced supplement literatures of any condition — primarily because the field needed effective alternatives to pharmaceuticals with significant side effect profiles. Magnesium, riboflavin (B2), and CoQ10 each have multiple randomized trials supporting their use for migraine frequency and severity, and they appear in headache neurology guidelines as Level B (probably effective) or Level C (possibly effective) evidence. The stack is best used as PREVENTION (daily, ongoing) — not as acute migraine treatment. If you have not been formally diagnosed with migraine, the protocol still applies to general headache prevention but proper diagnosis is worth pursuing — migraines are often under-treated.
Hydration & Electrolytes
recovery
Most people drink enough water but consume far too little sodium relative to their activity level — particularly anyone exercising, low-carb dieting, in a hot climate, or drinking caffeine in volume. The result is "water-logged but mineral-poor" hydration that manifests as headaches, fatigue, muscle cramps, lightheadedness on standing, and poor exercise tolerance. This protocol focuses on the four electrolytes that matter most: sodium, potassium, magnesium, and chloride. Calcium gets a brief mention but is rarely the limiting factor in healthy adults.
Pre-Workout (Performance)
recovery
The commercial pre-workout category is bloated with proprietary blends, exotic-sounding ingredients, and aggressive marketing — but the actual evidence-backed ingredients are short and well-studied: citrulline (NO precursor, improves blood flow and reduces perceived exertion), beta-alanine (carnosine precursor, buffers muscle pH in high-intensity work), caffeine (the most-evidenced ergogenic aid in sports nutrition), and taurine (ergogenic with synergistic effects). This stack is what would actually be in a clean pre-workout — without the kitchen-sink approach that produces $50/month products. Most commercial pre-workouts contain these ingredients at sub-effective doses behind a "proprietary blend" label. Use 30-60 minutes before training sessions where performance matters. Daily use builds caffeine tolerance and reduces effect — skip pre-workout on light/recovery days or save it for high-intensity sessions.
Joint Health & Mobility
recovery
Joint discomfort is one of the most universal aging symptoms — and one of the most over-supplemented categories in the entire industry. The literature for glucosamine and chondroitin is genuinely mixed: some trials show modest pain and function improvements in moderate osteoarthritis; others find no effect over placebo. Omega-3 has more consistent evidence for inflammatory joint pain. Curcumin (with appropriate bioavailability enhancement) has rapidly accumulating trial evidence comparable to NSAIDs in mild-to-moderate osteoarthritis. UC-II (undenatured type II collagen) has small but clean trials for knee osteoarthritis. This stack is for everyday joint maintenance and mild-to-moderate osteoarthritis — not a substitute for orthopedic care of serious joint disease.
Post-Workout Recovery
recovery
Recovery determines your next training session, not the workout you just finished. The best-evidenced supplemental levers are unglamorous: enough protein to drive muscle protein synthesis, creatine to maintain phosphocreatine stores, and a small set of anti-inflammatory aids for high-volume blocks or competition stretches. This protocol assumes you are training consistently — three or more sessions per week — and want to recover better between them. If you train less, the protein you eat at meals is sufficient.
Chronic Fatigue Recovery
energy· 3 shared ingredients
Persistent fatigue lasting 6+ months — distinct from temporary tiredness — affects roughly 25% of primary care visits and is one of the most under-diagnosed symptom clusters in medicine. The differential diagnosis is wide: anemia, hypothyroidism, sleep apnea, depression, chronic infections, mitochondrial dysfunction, post-viral syndromes (ME/CFS, Long COVID), early autoimmune disease. This protocol is for ADJUNCTIVE support after appropriate medical workup — supplements complement proper diagnostic workup and treatment of underlying causes. CoQ10 and NAD+ precursors (NMN or NR) target mitochondrial function (a documented finding in many chronic fatigue states); iron and B12 correct common reversible deficiencies; magnesium supports the multiple systems affected by chronic fatigue. If you have persistent unexplained fatigue, please see a doctor BEFORE relying on supplementation alone. The labs that should be done first: CBC, ferritin, TSH/free T4/T3, vitamin B12, vitamin D, fasting glucose, HbA1c, lipid panel, hsCRP, ESR, and consideration of further workup based on symptoms.
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Coming to App StoreDisclaimer: These statements have not been evaluated by the FDA. This protocol is educational, not a substitute for personalized medical advice. Talk to your doctor before starting any new supplement regimen — especially if you're pregnant, breastfeeding, on medications, or managing a chronic condition. Last updated 5/20/2026.