Pack size: 100 capsules

ShopAmino acids and proteins

Doctor Life

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L-Arginine

L-Arginine 600 mg · Nitric oxide precursor

53,99 zł

A focused L-arginine supplement without an extensive blend of active ingredients
A convenient addition to an active lifestyle and sports nutrition routine
Caffeine-free for a stimulant-free arginine routine

Overview

One amino acid, clearly measured. Each L-Arginine capsule provides 600 mg, with 1800 mg in the recommended daily serving of three capsules. A focused formula without the caffeine, botanical blends, or multiple extras found in many pre-workout products.

At the heart of the formula / L-Arginine

Thoughtful support. Clear purpose.

01A focused L-arginine supplement without an extensive blend of active ingredients
02A convenient addition to an active lifestyle and sports nutrition routine
03Caffeine-free for a stimulant-free arginine routine
04Can be taken independently of workout timing, between meals or before bed as directed
05A single-ingredient formula makes daily intake easier to track
06A vegan pullulan capsule for those who avoid gelatin

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L-Arginine

Made for your daily routine.

L-arginine is an amino acid used by nitric oxide synthase to produce nitric oxide. It also participates in the urea cycle and pathways involved in creatine synthesis. These metabolic roles have prompted research in exercise physiology.

The formula contains L-arginine as its single active ingredient, without stimulants or other amino acids. A clearly stated amount makes it easier to track intake alongside an existing routine.

The pullulan capsule is suitable for vegans and vegetarians. Take three capsules between meals or before bedtime, as directed.

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L-Arginine

Why does L-arginine matter?

The body can make L-arginine, which serves as both a protein building block and a substrate for nitric oxide production. It also participates in the urea cycle, which processes nitrogen from amino acid metabolism. Researchers study these roles in several settings, including exercise.

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L-Arginine

What research informs L-Arginine?

Reviews of controlled trials have examined aerobic and anaerobic exercise measures, with findings varying by amount, duration, and activity. Some longer protocols used 1.5–2 g daily; one trial in soccer players used 2 g for 45 days and assessed VO₂max. This formula provides 1.8 g daily, but the research does not establish a guaranteed performance benefit.

Ingredients / Doctor Life

Every ingredient. Clearly explained.

Each ingredient, its form and quantity — in one place.

Ingredient amounts for the servings shown in the table.
Ingredient	1 capsule	3 capsules
L-arginine	600 mg	1,800 mg

*NRV: Nutrient Reference Value

Full ingredient list

L-arginine, capsule shell (bulking agent: pullulan).

How to use

Part of your daily rhythm.

How to use

Take 3 capsules between meals or before bedtime, with at least 250 mL of water.

Important information

Do not exceed the recommended daily serving. Food supplements should not replace a varied diet. A balanced diet and a healthy lifestyle are recommended. Not intended for use during pregnancy or breastfeeding. Store at room temperature, at or below 25°C, out of reach of young children.

Science & sources

Understand the formula.

L-arginine is widely studied in relation to nitric oxide metabolism and physical performance. These publications examine regular use at doses near this product's daily serving, alongside meta-analyses of controlled exercise studies.

These publications concern the studied ingredients or formulas. They do not all evaluate the finished Doctor Life product, and research results do not guarantee individual outcomes.

01Effects of Arginine Supplementation on Athletic Performance Based on Energy Metabolism: A Systematic Review and Meta-Analysis

Aitor Viribay, José Burgos, Julen Fernández-Landa, Jesús Seco-Calvo, Juan Mielgo-Ayuso

Nutrients (2020), 12(5), 1300. DOI: 10.3390/nu12051300; PMID: 32370176.

A meta-analysis of studies on aerobic and anaerobic performance reported favorable results for arginine supplementation. In longer-term protocols, 1.5–2 g daily for four to seven weeks was associated with improved aerobic performance measures. Doctor Life L-Arginine provides 1.8 g per daily serving, within that range.

Read publication ↗

02The effect of L-arginine supplementation on body composition and performance in male athletes: a double-blinded randomized clinical trial

Naseh Pahlavani, Mohammad Hassan Entezari, Morteza Nasiri, Ali Miri, Mahsa Rezaie, Mojgan Bagheri-Bidakhavidi, Omid Sadeghi

European Journal of Clinical Nutrition (2017), 71(4), 544–548. DOI: 10.1038/ejcn.2016.266; PMID: 28120856.

In a double-blind, placebo-controlled trial, soccer players took 2 g of L-arginine daily for 45 days. The supplemented group showed a greater increase in VO₂max than the placebo group. The dose was close to the 1.8 g supplied in a daily serving of this product.

Read publication ↗

03The effect of L-arginine supplementation on maximal oxygen uptake: A systematic review and meta-analysis

Shahla Rezaei, Maryam Gholamalizadeh, Reza Tabrizi, Peyman Nowrouzi-Sohrabi, Samira Rastgoo, Saeid Doaei

Physiological Reports (2021), 9(3), e14739. DOI: 10.14814/phy2.14739; PMID: 33587327.

A meta-analysis of 11 randomized clinical trials found increased VO₂max after L-arginine supplementation compared with control groups. The findings contribute to research on L-arginine and exercise capacity.

Read publication ↗

FAQ / L-Arginine

Good questions. Clear answers.

Talk to us ↗

How does the 1,800 mg daily serving relate to research?

The 1.8 g serving falls within the 1.5–2 g range used in some studies lasting four to seven weeks. Study populations and protocols vary, so the amount alone does not predict a result.

How do arginine and citrulline differ?

L-arginine is directly used to make nitric oxide. Citrulline can be converted into arginine, and pharmacokinetic studies have examined its ability to raise blood arginine levels. This product supplies L-arginine alone; the appropriate choice depends on your needs.

Must L-arginine be taken immediately before exercise?

No. The label directs you to take three capsules between meals or before bedtime. Research includes both single-serving and longer-term protocols, so there is no requirement to fit this product into a specific pre-workout window.

Is L-arginine simply a pump supplement?

L-arginine is an amino acid with defined metabolic roles, including nitric oxide production. Exercise findings depend on the amount, duration, and type of activity. This product provides a specified serving without promising an immediate pump effect.

Does L-arginine build muscle or increase growth hormone?

This product is not presented as a growth hormone booster or muscle-building supplement. In one trial using 2 g daily, VO₂max changed without significant changes in body weight, fat mass, or lean mass.

Can I combine L-Arginine with creatine, citrulline, or a pre-workout?

Check the full ingredient lists before combining products. A pre-workout may already contain arginine or other ingredients that affect cardiovascular function. Review the combination with a health professional if you take medication or have a medical condition.

Is extra caution needed with blood pressure medicines, nitrates, or erectile dysfunction medication?

Yes. Because L-arginine is involved in nitric oxide metabolism, it may add to the effects of these medicines on blood pressure. Speak with your doctor or pharmacist before use.

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