A Stimulant-Free Pre-Workout Routine with L-Citrulline and L-Arginine

Training late, sensitive to caffeine or already on your second coffee? Here is a simple pre-workout routine built on two amino acids, with no stimulants.

A red beetroot drink, fresh beets and running shoes beside a ZuvoNutrition jar on a sunlit counter

In short

Nitric Oxide+ is two capsules of L-citrulline and L-arginine, with no caffeine and no sugar. Take them with water 20 to 30 minutes before training, then warm up as usual.

Why go stimulant-free?

Many pre-workouts are built around caffeine. That works for some people, but not if you train in the evening, you are sensitive to caffeine, or you have already had coffee that day. A stimulant-free formula lets you keep a pre-training routine without adding to your caffeine total.

What is in each serving (2 capsules)

L-citrulline DL-malate 400 mg
L-arginine HCl 350 mg
L-arginine AKG 50 mg
Caffeine None
Sugar None

The capsules are vegan cellulose, with brown rice flour as the only other ingredient.

What these amino acids are

L-arginine is an amino acid your body uses to make nitric oxide, a molecule involved in blood flow.* L-citrulline is an amino acid your body converts into L-arginine. Many active people add them to their routine for that reason. Nitric Oxide+ uses two forms of arginine (HCl and AKG) alongside citrulline malate.

A simple routine

  1. 20 to 30 minutes before training: take 2 capsules with 6 to 8 oz of water.
  2. Warm up: 5 to 10 minutes of easy movement for the muscles you are about to train.
  3. During: sip water, especially in long or hot sessions.
  4. After: a protein shake or a meal with protein.

Because there is no caffeine, the timing works the same for a 6 a.m. session or a 7 p.m. one.

Pairing it with creatine

Creatine is a separate, daily habit: one scoop a day, at any time. If you train most days, a simple stack is Nitric Oxide+ before training and an unflavored scoop of Creatine Monohydrate in your post-workout shake. Our Performance Bundle puts those two together with chocolate whey protein.

Good to know

  • Do not take more than the 2 capsules on the label.
  • If you take blood pressure medication or any prescription medication, ask your doctor or pharmacist before using an arginine or citrulline supplement.

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*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. This guide is general information, not medical advice. If you are pregnant, nursing, under 18, taking medication or have a medical condition, talk to your doctor or pharmacist before starting a supplement.

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