Citrulline Malate: Will it Improve Strength and Endurance?

If you’ve ever read the side of your pre-workout canister and seen claims that it will, “give you the sickest pump of your life”, you may have already consumed citrulline malate.

While not the only nitric oxide supplement (another popular one being beetroot juice) it is a common addition to many pre-workouts 1. Due to it’s affordability and 2. In hopes that it results in a consumer getting a pump so good they continue to buy their pre-workout supplement.

But what even is Citrulline Malate and what does it actually do? Here’s what you should know about the supplement Citrulline Malate, and if it’s got more to offer than just a sick pump.

1. What is Citrulline Malate?

Citrulline Malate is a combination of the amino acid L-Citrulline (this is a non-essential amino acid that our body is capable of producing) and Malate (malic acid in the form of a salt). The two are combined in ratios of either 1:1 or 2:1, and while 2:1 will be the favored ratio wherever you look on the internet, don’t overthink it when searching for a product. For starters, the research itself on Citrulline Malate ratios isn’t so cut and dry, additionally ratios listed on your Citrulline Malate product are likely to differ from the true ratio of what you are consuming (I.E your “2:1” product could very well be 1:1).

Citrulline Malate is readily available as a cheap standalone supplement, and citrulline itself can be found in foods such as watermelon, pumpkins, and cucumber (granted the exact amount your are consuming will be hard to estimate).

2. How Does it Work?

Citrulline Malate’s main stick is that it is a Nitric Oxide precursor. The L-citrulline in Citrulline Malate, can be converted to Arginine in our body which in turn can be directly converted to NO. Basically, by consuming Citrulline Malate we are increasing our availability of Arginine and in turn our ability to generate NO.

That might leave you asking why we don’t just supplement directly with Arginine, and well…we tried. Arginine simply doesn’t have the bio-availability (this refers to the ability of a drug or other substance to be absorbed and used by the body) that Citrulline Malate does. Therefore, Citrulline Malate has taken over as the dominate supplement.

Increasing our ability to produce NO is seen as desirable for a few reasons. Notably NO is a vasodilator which will promote blood flow in the body. It’s this vasodilation effect that pre-workout companies hope will increase your pump. In addition to possibly giving you the best pump of your life, NO potentially has effects that improve our energy efficiency (how much energy we use to complete physical activity), our overall energy metabolism, and help with muscle fatigue.

Additionally, what makes Citrulline Malate slightly different from other NO supplements is that being a precursor for NO isn’t it’s only trick. Citrulline also helps facilitate ammonia clearance which may help decrease fatigue, and malate could potentially contribute to ATP production. Keep in mind with the current research on Citrulline Malate it cannot be guaranteed which of these effects are truly occurring if any of the above at all. This leaves the supplement in a frustrating state of uncertainty as to what it actually does.

3. Strength/Hypertrophy Benefits

Strength Endurance Improvements:

There is some limited evidence to suggest that Citrulline Malate can improve “strength endurance“. What that translates to is a modest improvement in your work capacity (how many reps you could perform across multiple sets before reaching failure). Individuals will extrapolate from this that increased work capacity means bigger muscles and bigger 1RMs down the line and…

…it’s just too much to claim with the research we have.

Could this be the case? Yes. Should you claim it with 100% certainty? No.

Citrulline Malate should not be put on the same pedestal as a supplement such as creatine. Citrulline Malate does not have the dominate and overwhelming research backing it in terms of effect as creatine does. This isn’t to say the purported effects of Citrulline Malate don’t exist. It’s just we can’t claim the effects to a high degree of certainty.

Nitric Oxide Supplement:

Because Citrulline Malate will objectively increase NO production when properly dosed, the vasodilation effect of all that NO could lead to you experiencing “better pumps” due to increased cellular swelling. For some people this alone may be worth the price of admission.

4. Endurance Benefits

Increased blood flow, improved energy efficiency, increased time to muscle fatigue, increases in ATP production during exercise, all of these things sound great for any endurance athlete out there.

Unfortunately, we are falling into the same pitfall as we were for the potential benefits to strength performance. Conclusively claiming any of these effects is sketchy at best for Citrulline Malate. The potential is definitely there for some of the proposed benefits to endurance, but this is an area that definitely needs more research before anything can be said for certain.

5. Proper Dosage/Is it Safe?

Proper dosing for Citrulline Malate currently stands at 6-8g with 8g commonly being used in studies. As we discussed above the 2:1 ratio is preferred, whether you are actually getting that or not is up in the air.

What’s important to note is that timing does matter when it comes to the consumption of Citrulline Malate. It takes awhile for the supplement to be converted in our body and because of this it is recommended to take 1-2 hours before you intend to workout. This makes it ideal to purchase Citrulline Malate as it’s own standalone product as most pre-workouts are consumed approximately 30 mins before a workout.

There is currently no safety concern over the proper use of Citrulline Malate, but as with everything you should consult with your doctor before using if you are unsure.

6. Conclusion

Citrulline Malate is still in it’s infancy when it comes to the research surrounding it, making definite conclusions about the supplement difficult to make.

What is known for sure is that properly dosed Citrulline Malate will result in an increase in NO production, the potential effects of the increase in NO, however, are what is up in the air.

The good news is that Citrulline Malate is both safe and extremely cheap. This means you can try it out for yourself and make your own conclusions on if it is going to support your specific goals or not relatively risk free.

Matt Molloy

Matt Molloy

I'm a graduate the University of Pittsburgh with a major in Exercise Science. I’m a local guy (North Penn) and athletics has dominated my life. I've led teams in basketball, baseball, soccer, golf and my passion, long distance running. I've been strength training for 6 years with a focus in power-lifting but have recently stretched to strongman since joining the pride here at the Den. When I’m not in the gym I enjoy, spending time with my friends, music, and relaxing and playing some video games.