PEScience High Volume

PEScience High Volume — Caffeine-Free Pump, Two Nitric Oxide Pathways

High Volume does one job and does it honestly: pumps. 6g of pure L-citrulline, 2g of arginine nitrate (NO3-T®) and HydroMax® glycerol, with taurine, vitamin C and electrolytes. No caffeine, no beta-alanine, no proprietary blends. Vegan, gluten free. In stock at TopDog Nutrition.

Two Nitric Oxide Pathways, Not One

This is what separates High Volume from most pump products. Your body makes nitric oxide two different ways, and High Volume targets both.

The arginine pathway: L-citrulline converts to arginine in the kidneys, and arginine is converted by nitric oxide synthase into nitric oxide. Supplementing citrulline raises plasma arginine more effectively than taking arginine directly, because oral arginine is largely broken down in the gut before it gets anywhere.

The nitrate pathway: arginine nitrate (NO3-T®) supplies dietary nitrate, which converts to nitrite and then to nitric oxide through a completely separate, enzyme-independent route. It also delivers arginine directly.

Two pathways working at once produces a broader nitric oxide response than citrulline alone can generate. That's the mechanism behind the pump this product is known for.

6g Pure L-Citrulline — Read the Label Carefully

PEScience use pure L-citrulline, not citrulline malate. The difference matters: citrulline malate is citrulline bound to malic acid, and only around 55–65% of the stated weight is actual citrulline. A product claiming 6g of citrulline malate is really giving you under 4g of the active compound.

6g of pure L-citrulline is 6g of citrulline. It's at the top of the researched effective range.

HydroMax® Glycerol — The Hyperhydration Ingredient

Glycerol is a genuinely different mechanism from the nitric oxide ingredients, and it's what makes the pump last.

Glycerol is an osmolyte — it pulls water into cells and holds it there. HydroMax® is a concentrated, stabilised glycerol powder at 65% concentration, which solves the clumping problem that made older glycerol supplements difficult to work with.

The practical effect is intramuscular hyperhydration: more fluid held inside muscle cells, which means fuller-looking muscle, better resistance to fatigue, and a pump that persists after the session rather than fading on the drive home.

Electrolytes, Taurine and Vitamin C

• Sodium and magnesium — the electrolytes that drive fluid balance. Glycerol pulls water into cells, but that only works if your electrolyte status supports it. The two ingredients are doing complementary jobs.
• Taurine — another osmolyte, contributing to cell volumisation alongside the glycerol, plus a role in muscle function and fatigue resistance.
• Vitamin C — an antioxidant that helps protect nitric oxide from oxidative degradation, extending how long the vasodilation lasts.

Why Caffeine-Free Is the Feature

High Volume is stimulant-free on purpose, and that opens up uses a caffeinated pre-workout can't cover:

• Evening training. Caffeine's half-life is 5–6 hours. A stimulant pre-workout at 7pm costs you sleep, and sleep is where the adaptation actually happens. High Volume doesn't.
• Stacking with your own caffeine. Already had coffee, or taking a separate stimulant? Add pump support without doubling up.
• Caffeine sensitivity. Full performance support without the stimulant load.
• Stacking with Prolific. One scoop of each is PEScience's own recommended combination — Prolific's energy and focus plus High Volume's pump.

Directions

Mix 1–2 scoops in 250–350ml of water, around 30 minutes before training.

Dose by bodyweight: one scoop if you're 73kg (160lb) or under, two scoops if you're over. The full 6g citrulline and 2g arginine nitrate figures are for the two-scoop serve.

Drink plenty of water alongside it. Glycerol works by holding water in your cells — it needs water available to do that, and taking it dehydrated defeats the purpose.

Frequently Asked Questions

Will it give me energy?

No. It's caffeine-free and contains no stimulants. You'll get pump, blood flow and hydration support — the energy has to come from elsewhere.

Any tingling?

None. No beta-alanine, no niacin flush. Nothing in it causes paraesthesia.

Can I take it every day?

Yes. No stimulants means no tolerance and no timing restrictions.

How many servings per tub?

36 scoops — 18 servings at the full two-scoop dose, or 36 if you're using one scoop.

Does it clump?

Glycerol is hygroscopic, meaning it attracts moisture from the air. Some minor clumping is normal. Keep the lid sealed tight and use it within about three months of opening for the best texture.