Until you have achieved “the pump” you haven’t fully lived.
If you have never walked out of the gym with your biceps feeling like they are going to explode, your whole life has been a lie.
I’m only half kidding here. Well, actually I am not kidding at all; the pump is the best.
In fact, there is a whole class of supplements that were originally designed to help you achieve the pump, known today as nitric oxide boosters.
More recently, nitric oxide boosters have been utilized in wider applications as they are meant to increase blood flow.
Increased blood flow can improve nutrient delivery to muscle tissue, allowing you to train longer, harder, recover better, and makes achieving the elusive pump easier.
While most nitric oxide boosting supplements contain a plethora of ingredients, there are really only a few things you need to know about to really understand NO boosters.
What is Nitric Oxide?
So before we go any further we should probably fill you in on what the heck nitric oxide is and why the heck you would want to boost it.
Nitric oxide causes vasodilation. This effectively increases blood flow which can increase nutrient and oxygen delivery to the muscles. Essentially, vasodilation gives your muscles more go juice.
Currently, the results are mixed and we don’t have a slam dunk case for it. This supplement may be a case of “responders vs non-responders” and some self-experimentation may prove that it is an effective supplement for you.
The Deeper Dive: The real science from studies done on L-arginine studies indicate that it does get taken up into the body and that nitric oxide boosting supplements with L-arginine do effectively increase arginine levels.
However, the increase of arginine levels in the blood doesn’t always translate into efficacy for blood flow or improvement in work capacity. One study has shown that arginine supplementation increases levels of arginine in the blood but does not increase levels of nitric oxide or muscular blood flow, nor does it enhance muscle protein synthesis.1
Yet, another shows that it increases blood volume but not strength performance.2
Even longer term supplementation of arginine appears to be largely ineffective. 7 days of supplementing with 12d/day of an arginine-alpha-ketoglutarate supplement showed that it did indeed increase plasma levels of L-arginine but had zero effect on hemodynamics or blood flow.3 More studies have shown no meaningful or significant increase in training capacity.
Currently, the evidence suggests that L-arginine may increase circulatory blood flow, but does not consistently or meaningfully increase training performance. No it isn’t all doom and gloom as when you look deeper into the research it appears that there are definitely “responders” and “non-responders” (I looked at a lot of papers and made assumptions based on means and standard deviations).
Perhaps it is time to enter a brand new era of NO boosting and find something that is more effective.
The Quick and Dirty: L-arginine is only one way to increase nitric oxide in your blood and increase blood and oxygen deliver. There appears to be a different molecule that is more effective than L-arginine at boosting NO and at improving training.
Recent evidence has shown that inorganic nitrate (NO3-) from dietary sources can also increase NO production.4 Most supplemental nitrate comes from beet root juice or nitrate salts.
The Deeper Dive: Dietary NO3- is broken down into a bioactive form nitrite (NO2-) which causes a rise in plasma NO2-.5 Plasma NO2- is then further reduced in the blood and tissues into bioactive NO. Let’s stop and take a look and compare this to L-arginine.
Now that we have an idea of how it works, we can dive into what the research says about how effective it is in improving performance.
When I set out to write this article I knew I was going to need a bit of backup so I contacted a colleague of mine, Dylan Dahlquist MSc, who is well versed in the research regarding dietary nitrates and human performance and he got me up to speed on the research.
Several studies have shown that consuming roughly 8 mmol/nitrate per day through beet root juice can improve performance during a cycling trial.6 One of the interesting things that has come out of the research is that it may improve “efficiency”, meaning that less ATP is required to complete the same amount of work.
This is pretty mind blowing and no one really understands exactly how this happens . . . science is hard. One hypothesis is that it improves mitochondrial function and makes it more efficient, which is pretty cool.7
When we summarize what we know about nitrate supplementation is that it appears to be a bit more effective than L-arginine at accomplishing the same task and may have performance enhancing effects. The studies conducted clearly show an increase in NO production with acute and/or chronic supplementation and may elicit the ergogenic effects and improve athletic performance.
If used as a pre-workout supplement it is wise to take it about 2-3 hours before training as blood levels typically peak roughly 2-3 hours after ingestion, which relates to the peak increase in NO bioavailability.5
The Wrap Up
Nitric oxide boosters are based on the idea that increased blood flow is a good way to boost performance. There are really two main supplements that work to boost nitric oxide, L-arginine and Nitrate.
Based on what the research tells us it looks like nitrate is the much better option than L-arginine for this specific task and if you are looking for a supplement that works as advertised that is the way to ensure you maximize your investment.
- Bolus arginine supplementation affects neither muscle blood flow nor muscle protein synthesis in young men at rest or after resistance exercise.
- Acute l-arginine supplementation increases muscle blood volume but not strength performance.
- Effects of 7 days of arginine-alpha-ketoglutarate supplementation on blood flow, plasma L-arginine, nitric oxide metabolites, and asymmetric dimethyl arginine after resistance exercise.
- Dietary nitrate reduces maximal oxygen consumption while maintaining work performance in maximal exercise.
- Dietary nitrate supplementation improves rowing performance in well-trained rowers.
- Nitrate supplementation's improvement of 10-km time-trial performance in trained cyclists.
- Dietary inorganic nitrate improves mitochondrial efficiency in humans.