The Top 5 Supplements for Stamina and Endurance

By Nutrimatch editorial team · Published 5 May 2026 · Last reviewed 2 June 2026

What endurance supplements can and cannot do

Endurance performance — the ability to sustain effort over minutes to hours — is primarily determined by aerobic fitness, fuelling strategy, and pacing. No supplement replaces training volume or race-day nutrition. But a few compounds have evidence for meaningful marginal improvements, and when races are decided by seconds or percentages, those margins matter.

The evidence base for endurance supplements is more nuanced than for strength. While creatine dominates the strength category, endurance has several compounds with evidence across different mechanisms — from buffering muscle acidity to improving oxygen utilisation to reducing perceived effort.

How different supplements help endurance

Caffeine is the strongest ergogenic aid for endurance. Multiple meta-analyses show improvements of 2–4% in time-trial performance and time to exhaustion. It works through reduced perceived effort, increased fat oxidation, and improved neuromuscular function. The effective dose is 3–6 mg per kg bodyweight, taken 30–60 minutes before exercise. Response is highly individual and is reduced by habitual caffeine use.

Beta-alanine increases muscle carnosine, which buffers hydrogen ion accumulation during sustained high-intensity effort. The benefit is most pronounced in efforts lasting 1–10 minutes — events like 800m–3000m runs, 4km pursuit cycling, or high-intensity interval efforts within longer races. For pure long-duration endurance (marathon, ultra), the benefit is smaller.

Beetroot juice (dietary nitrate) improves exercise economy by reducing the oxygen cost of a given workload. The effect is most consistent in recreational athletes and at submaximal intensities. Elite athletes, who already have highly efficient oxygen utilisation, tend to see smaller benefits. The effective dose is about 6–8 mmol nitrate, typically consumed 2–3 hours before exercise.

Sodium bicarbonate is an extracellular buffer that reduces the performance-limiting effects of acidosis during high-intensity endurance efforts. It has consistent evidence for 1–7 minute all-out efforts but can cause gastrointestinal distress, which limits its practical use for many athletes.

Context: what matters more

Training. The performance gains from adding structured intervals, increasing weekly volume appropriately, or improving pacing strategy will dwarf any supplement effect.

Nutrition. Carbohydrate availability during endurance exercise has a larger impact on performance than any supplement. Proper fuelling during efforts longer than 60–90 minutes is not optional.

Iron status. Low ferritin is common in endurance athletes, particularly female runners. A blood test for ferritin and haemoglobin should be a first step before any supplement. Correcting iron deficiency improves endurance performance more than any non-essential supplement.

Sleep and recovery. Chronic under-recovery limits training adaptation more than any supplement can compensate for.

Practical recommendations

For most recreational endurance athletes, caffeine and beetroot juice before key sessions or races are the most practical and evidence-based choices. Beta-alanine requires 4–6 weeks of daily loading (3.2–6.4 g per day) to saturate muscle carnosine stores, so it needs to be started well before any target event.

How to use this guide

The supplements below are ranked by evidence quality for stamina and endurance outcomes. Consider your event duration, intensity, and training status when choosing which to try — the optimal supplement differs between a 5K runner and an ultramarathon cyclist.

Common misconceptions

Beetroot juice provides dramatic endurance gains. The effect is real but modest — typically 1–3% improvements in time-to-exhaustion. Real and meaningful for competitive contexts; subtle for recreational training.

Caffeine tolerance ruins its endurance effect. Habituation reduces the acute effect but does not eliminate it. Strategic abstinence (3–5 days) before key events restores most of the effect.

Iron is universally helpful for endurance. It helps people who are iron-deficient or anaemic. Supplementing in adequate-status athletes does not improve endurance and risks iron overload.

Pre-workout supplements are necessary. They are not. Caffeine and a small carbohydrate intake achieve most of what's in commercial pre-workouts at a fraction of the cost.

More carbohydrate during long exercise is always better. Above 60–90 g/hour, the gut typically cannot absorb more, and additional intake causes gastrointestinal distress.

FAQ

How long before I notice effects? For caffeine and beetroot: acute, within hours. For iron in deficient people: 4–8 weeks. For beta-alanine and creatine: 2–4 weeks of consistent use.

Can I combine endurance supplements? Yes. A common stack is caffeine + beetroot before key sessions, with creatine and adequate iron status as chronic foundations.

Should I test ferritin? For endurance athletes with persistent fatigue or declining performance, yes. Low ferritin without overt anaemia is common and responds to iron supplementation.

Will these help in shorter, high-intensity exercise? Caffeine and beta-alanine help. Beetroot helps with sustained sub-maximal effort more than with short maximal efforts.

Are these safe long-term? At standard doses, the supplements with strong endurance evidence have good long-term safety profiles. Iron is the main exception — supplement only with verified deficiency.