Protocol · Fitness & Performance
Aerobic Exercise Performance (Endurance) Protocol
Caffeine and Beetroot Juice (Nitrate) are the core of this stack, with 4 supporting supplements. Each row gives the amount the protocol lists and the grade our evidence database holds for that supplement in Aerobic Exercise Performance (Endurance).
We are re-verifying the studies cited on protocol pages; only confirmed citations are shown.
The stack
6 supplements · 6 graded · 1 graded A · 1 confirmed study
| Grade | Supplement | Amount listed | Why it’s in the stack | Evidence on file | Shop |
|---|---|---|---|---|---|
| Primary stackThe core of this protocol | |||||
| Caffeine | Amount listed: 3–6 mg/kg body weight 30–60 min before exercise | Adenosine receptor antagonist that reduces perceived exertion, enhances fat oxidation, and improves endurance capacity
| Grade A for Aerobic Exercise Metrics4 studies · 799 people | ||
| Beetroot Juice (Nitrate) | Amount listed: 300–600 mg nitrate (500 ml beetroot juice) 2–3 hours before exercise | Increases nitric oxide availability, improving muscle efficiency and reducing oxygen cost of exercise
| Grade B for Aerobic Exercise Metrics20 people | ||
| Supporting stackListed as additions to the core | |||||
| Beta-Alanine | Amount listed: 3–6 g daily for 4+ weeks (chronic loading) | Increases muscle carnosine to buffer hydrogen ions during high-intensity efforts within endurance events
| Grade D for Aerobic Exercise Metrics115 people | ||
Confirmed studies for Beta-Alanine (titles as PubMed lists them) | |||||
| Sodium Bicarbonate | Amount listed: 0.2–0.3 g/kg 60–90 min before high-intensity portions | Extracellular buffer that neutralizes acid during intense exercise, delaying fatigue in prolonged efforts
| Grade B for Aerobic Exercise Metrics22 people | ||
| Iron | Amount listed: If deficient: 30–60 mg elemental iron daily with vitamin C | Essential for hemoglobin and myoglobin oxygen transport; deficiency severely impairs endurance
| Grade D for Aerobic Exercise Metrics2 studies · 14 people | ||
| Rhodiola Rosea | Amount listed: 200–600 mg standardized extract 30–60 min before exercise | Adaptogen that reduces perceived exertion and improves oxygen utilization during prolonged exercise
| Grade B for Aerobic Exercise Metrics668 people | ||
Shop the evidence-backed picks
The collection holds the supplements we grade A or B for its theme, in third-party tested products where the catalog has them. It opens in our Fullscript store. You can look through it without signing in; Fullscript asks for a free account to order.
Or shop one supplement
The 4 supplements in this protocol graded A or B. Each opens third-party tested products, matched to the dose above where we can.
- Grade A
- Grade B
- Grade B
- Grade B
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How this protocol works
In plain language
Aerobic exercise performance depends on oxygen delivery, energy efficiency, and the ability to delay fatigue. Whether you're running, cycling, swimming, or doing any endurance activity, these supplements target the key physiological limiters of aerobic performance.
- Caffeine is the most proven ergogenic aid for endurance exercise. It works by blocking adenosine receptors in the brain, reducing the perception of effort—so exercise feels easier at the same intensity. It also increases fat oxidation (sparing glycogen) and improves muscle contractility. Studies consistently show 2-4% improvements in endurance performance, which is huge in competitive settings. Take 3-6mg/kg about 30-60 minutes before exercise.
- Beetroot Juice (Nitrate) is the second most effective supplement for endurance. Dietary nitrate is converted to nitric oxide, which improves the efficiency of muscle contraction—you use less oxygen to produce the same power output. This translates to improved time trial performance and time to exhaustion. The effect is most pronounced in recreational athletes and at moderate intensities. Drink 500ml beetroot juice (or equivalent nitrate dose) 2-3 hours before exercise.
- Beta-Alanine increases muscle carnosine levels, which buffers acid produced during intense efforts. While primarily beneficial for shorter, high-intensity exercise, it helps with hard efforts within longer endurance events—think the final sprint, hill climbs, or surges. Requires daily loading for 4+ weeks.
- Sodium Bicarbonate is an extracellular buffer that helps neutralize acid during high-intensity portions of endurance events. Most useful for events with significant high-intensity components or repeated hard efforts. Can cause GI distress—test in training.
- Iron is critical for endurance—it's essential for hemoglobin (carries oxygen in blood) and myoglobin (stores oxygen in muscle). Iron deficiency is common in endurance athletes, especially female athletes, and severely impairs performance. Get ferritin tested; supplement only if deficient.
- Rhodiola Rosea is an adaptogen that may reduce perceived exertion and improve performance during prolonged exercise. Effects are more subtle than caffeine but may provide additional benefit.
Expected timeline: Caffeine and nitrate work acutely (single dose before exercise). Beta-alanine requires 4+ weeks of daily supplementation. Iron correction takes 8-12 weeks.