Muscle pump supplements rely on specific ingredients that support nitric oxide production, blood flow, hydration, and muscle fullness. Many of these formulas are used as non-stim pre-workouts, giving athletes a way to improve training performance without relying on caffeine.
While there are many ingredients in pump formulas, a few stand out as the most widely used and best researched.
L-Citrulline
L-citrulline is one of the most popular ingredients for muscle pumps because it helps raise arginine levels in the body more effectively than arginine itself. Higher arginine levels may support nitric oxide production and circulation.1
L-citrulline is commonly used in dosages around 6 to 8 grams before training in many pump-focused formulas.
Citrulline Malate
Citrulline malate combines citrulline with malic acid. In addition to supporting nitric oxide production, it may help reduce fatigue and improve training volume during resistance exercise.2
This is why it is commonly found in both nitric oxide boosters and pre-workout formulas designed for pumps and endurance.
Beetroot Extract and Nitrates
Beetroot extract is valued for its nitrate content. Nitrates are converted into nitrite and then nitric oxide in the body, providing an additional pathway for nitric oxide support.3
Nitrate-based ingredients may help support:
- Blood flow
- Exercise efficiency
- Endurance performance
- Muscle pumps during training
Glycerol
Glycerol is often used in pump supplements to support hydration and muscle fullness. By helping increase total body water and fluid retention in muscle tissue, glycerol may contribute to a fuller feeling during training.4
This is why glycerol is frequently included in modern high-pump, stim-free formulas.
Agmatine Sulfate
Agmatine is another ingredient often used in pump formulas. It may help support nitric oxide signaling and is commonly included alongside citrulline and nitrates in pump-focused blends.5
Although research on agmatine is more limited than citrulline, it remains a popular ingredient in nitric oxide formulas.
How These Ingredients Work Together
Many of the best pump supplements combine multiple ingredients to support circulation through different mechanisms:
- Citrulline: Supports arginine and nitric oxide production
- Nitrates: Support the nitrate-to-nitric-oxide pathway
- Glycerol: Supports hydration and muscle fullness
- Agmatine: Supports nitric oxide signaling
If you want a deeper explanation of blood flow and vasodilation, read our guide on what nitric oxide is and how it supports muscle pumps.
Many of these ingredients are found in non-stim pre-workouts designed to improve pumps without caffeine.
You can also read our guide on how to maximize muscle pumps without stimulants for more practical tips.
Bottom Line
The best pump supplements typically combine nitric oxide boosters with hydration-support ingredients to improve circulation, muscle fullness, and performance during training. Citrulline, nitrates, glycerol, and agmatine are some of the most popular ingredients used in modern muscle pump formulas.
References
- Schwedhelm E, et al. Oral L-citrulline increases plasma arginine levels. Br J Clin Pharmacol.
- Pérez-Guisado J, Jakeman PM. Citrulline malate and resistance exercise performance. J Strength Cond Res.
- Lundberg JO, Weitzberg E, Gladwin MT. The nitrate-nitrite-nitric oxide pathway. Nat Rev Drug Discov.
- Goulet EDB. Glycerol-induced hyperhydration and endurance performance. Sports Med.
- Piletz JE, et al. Agmatine: clinical applications after 100 years in translation. Ann N Y Acad Sci.