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Limited evidencePhysical performance

AAKG (Arginine Alpha-Ketoglutarate)

AAKG is L-arginine bonded to alpha-ketoglutarate, sold on the promise of a bigger nitric oxide "pump" than plain arginine. Controlled trials find it raises plasma arginine but does not improve strength, endurance, or blood flow — citrulline is the better-supported pre-workout vasodilator.

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What the science says

  • Does not improve strength or muscular endurance Limited evidence

    In the largest controlled trial, 12 g/day AAKG for 8 weeks in 35 resistance-trained men raised 1RM bench press modestly but showed no advantage over placebo for Wingate peak power, and produced no change in body composition. A 2012 acute study giving 3,000 mg AAKG 45 minutes before training in trained and untrained men found no improvement in bench press or leg press reps to failure in either group.

  • Raises plasma arginine but not nitric oxide markers or blood flow Limited evidence

    Seven days of AAKG (12 g/day) significantly increased plasma L-arginine but did not increase nitrite/nitrate (NOx), did not increase brachial artery blood flow after resistance exercise, and did not reduce asymmetric dimethylarginine. Oral arginine is heavily degraded by intestinal and hepatic arginase, which is why citrulline — which bypasses first-pass arginase and raises plasma arginine more effectively — outperforms it.

  • The alpha-ketoglutarate half adds no proven benefit Limited evidence

    No published human trial has compared gram-for-gram AAKG against an equivalent dose of plain L-arginine for performance outcomes. The AKG moiety is a Krebs cycle intermediate with its own emerging longevity literature, but at AAKG doses roughly half the powder is AKG, meaning a 6 g scoop delivers only about 3 g of arginine.

Dosage & safety

Studied doseStudies used 3,000 mg acutely pre-exercise (no effect) or 4 g three times daily (12 g/day total) for 7-56 days. Typical label doses of 1-3 g per scoop in pre-workout blends are below anything ever tested. If you want a nitric-oxide pre-workout with real data, 6-8 g citrulline malate or 3 g L-citrulline has far stronger support.
SafetyGenerally well tolerated; 12 g/day for 8 weeks produced no clinically meaningful changes in blood chemistry, lipids or blood pressure. Common complaints are GI upset, bloating and diarrhea at multi-gram doses. Arginine can lower blood pressure additively with antihypertensives and PDE5 inhibitors, and may reactivate herpes simplex in susceptible people (arginine:lysine ratio). Avoid after recent myocardial infarction — a trial of high-dose arginine in post-MI patients was stopped early for excess mortality. Not banned in sport.

How to take it

TimingAcute pre-workout dosing showed nothing; the chronic trials dosed 4 g three times a day.
With food?Either way, though multi-gram doses on an empty stomach are more likely to cause diarrhoea.
Worth knowingIf nitric oxide is what you are after, 6–8 g citrulline malate has far stronger evidence for similar money — and avoid arginine entirely after a recent heart attack.

Interactions

With medications

  • antihypertensive medication

    arginine lowers blood pressure and can add to the drug's effect monitor blood pressure when starting multi-gram doses

  • PDE5 inhibitors (sildenafil, tadalafil)

    additive vasodilation and hypotension do not combine at high doses without medical advice

  • nitrates

    additive nitric-oxide-mediated vasodilation avoid the combination

With other supplements

  • citrulline or citrulline malate

    same nitric-oxide pathway, with no reason to pay for both pick one — citrulline has the better evidence

  • lysine

    a high arginine-to-lysine ratio can reactivate herpes simplex in susceptible people keep lysine intake up if you are prone to cold sores

Well-established interactions only — this is not a complete list. Always tell your doctor and pharmacist what you take.

Frequently asked questions

Does AAKG increase nitric oxide and pump?

The evidence says no. Seven days of AAKG at 12 g/day raised blood arginine but did not raise nitric oxide markers or increase blood flow after resistance exercise.

Does AAKG improve strength or performance?

Controlled trials find AAKG does not reliably improve strength or endurance: a 3,000 mg dose before training did not increase reps to failure, and 8 weeks at 12 g/day gave no advantage over placebo on peak power or body composition. The evidence is limited.

Is citrulline better than AAKG?

Yes. Citrulline bypasses the breakdown that destroys much oral arginine and raises blood arginine more effectively; 6-8 g citrulline malate or 3 g L-citrulline has far stronger support than AAKG.

Is AAKG safe?

AAKG is generally well tolerated, though multi-gram doses can cause GI upset and diarrhea. Arginine can add to the blood-pressure-lowering effect of antihypertensives, PDE5 inhibitors and nitrates, and should be avoided after a recent heart attack.

Scientific references

Where to buy

NutraBio, AAKG, 1.1 lb (500 g)

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