Citrulline vs Beetroot Nitrates: Which to Choose and for Whom

The choice between citrulline and beetroot nitrates depends above all on how you train. The editorial team examined typical scenarios - from a 10 km run to a "pump" workout - and explained which supplement makes sense for whom.

The main question - your type of load

The choice between citrulline and beetroot nitrates is best started not from the label but from an analysis of your own training. Both supplements affect the nitric oxide system, but the best results in studies were obtained under different conditions: nitrates in cyclic sports, citrulline in high-volume strength training.

The second question is the level of training. The effect of nitrates is most noticeable in recreational and moderately trained athletes; in world-class athletes, who already have a high capillary density and efficient NO metabolism, the gains are often minimal.

The third is practical circumstances: whether you are ready to drink beetroot juice 2-3 hours before the start, whether you use an antiseptic mouthwash, whether you have blood pressure problems or take medication. These details affect the choice no less than the mechanism of action.

The diagram below summarizes how the editorial team rates the suitability of each supplement for different loads.

Who beetroot nitrates suit

Runners, cyclists, amateur triathletes.It is precisely for efforts lasting from a few to about 30 minutes that the data are best. Reducing the oxygen cost of work lets you hold a set pace to exhaustion for longer.

Team sports with repeated sprints.Nitrates may improve the work of fast muscle fibers, which is why they are studied in football and other games with an intermittent load pattern. The evidence here is moderate but encouraging.

Training under hypoxic conditions.Since the conversion of nitrite into NO is enhanced under oxygen shortage, nitrates are theoretically especially useful at altitude. The results of studies in the mountains are mixed, but this niche is logical.

People with high blood pressure.Several studies, in particular the 2015 work by Kapil and colleagues, showed a sustained reduction in blood pressure with daily nitrate intake in people with hypertension. This is not a replacement for treatment, but it is an argument in favor of vegetables rich in nitrates - after clearing it with a doctor.

• Single dose in studies: ~6-13 mmol of nitrate (concentrated beetroot juice "shots" usually contain about 6-6.5 mmol).
• Intake 2-3 hours before exercise.
• Daily intake for 3-7 days before the start may give a more consistent effect than a single dose.

Who citrulline suits

High-volume strength training.If your workout is sets of 10-20 repetitions with short pauses, citrulline malate is a reasonable experiment. Some studies recorded more repetitions to failure and less muscle soreness the next day.

Those who cannot tolerate beetroot.Beetroot juice has a specific taste and causes pink coloring of the urine. Citrulline is more neutral in taste and is easily added to pre-workout mixes.

Those who train early and have no time.Citrulline is usually taken about an hour before training, whereas nitrates need 2-3 hours. For morning workouts right after waking up this can matter.

Studies used approximately 6 g of L-citrulline or 8 g of citrulline malate. You should look at the composition: many pre-workout complexes contain far less citrulline than the dose that was studied, so you should not expect a corresponding effect from them.

Comparison for typical scenarios

We gathered the most common reader queries into a table and indicated what we consider the rational choice.

Can you combine both supplements? In theory they activate different pathways, so a combination looks logical. In practice there are few studies of combinations, and their results do not show a convincing additional benefit. If you want to try, introduce the supplements one at a time to assess your reaction.

If the budget is limited, an alternative to beetroot concentrate is a diet rich in nitrates: beetroot, arugula, spinach, lettuce. The only problem is that the nitrate content in vegetables varies greatly, and it is hard to dose precisely.

For citrulline the "natural" alternative is watermelon, but to obtain a few grams of citrulline you would have to eat a great deal of it. So here a supplement is more practical than food.

Practical tips and common mistakes

The most common mistake with nitrates is antiseptic mouthwash. It suppresses the bacteria that reduce nitrate to nitrite, and the effect of the supplement weakens considerably. The same applies to frequently chewing antibacterial gum.

The second mistake is taking beetroot juice right before the start. The plasma nitrite peak occurs 2-3 hours later, so juice drunk 20 minutes before the start is unlikely to have time to help.

For citrulline the typical mistake is an insufficient dose. Pre-workout complexes often contain 1-3 g, which is below the doses from studies. It is also worth paying attention to the ratio of citrulline to malate in the formula.

Finally, test any new supplement in training, not on competition day. Stomach discomfort from concentrated juice or a large dose of citrulline is not something you want to discover at the start.

Editorial conclusions

For endurance - running, cycling, rowing, team sports - the editorial team prefers beetroot nitrates: the evidence base here is the strongest.

For strength training with a high number of repetitions it is smarter to try citrulline malate at a dose matching the research.

Both supplements have the greatest effect in amateurs and moderately trained people; the elite should test them individually. People who take cardiac nitrates or medications for potency should clear any NO boosters with a doctor.

We also recommend reading our materials on nutrition before a run, on beta-alanine for intense efforts, and on the composition of pre-workout complexes.

References

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3. Bailey SJ, Winyard P, Vanhatalo A, et al. Dietary nitrate supplementation reduces the O2 cost of low-intensity exercise and enhances tolerance to high-intensity exercise in humans. J Appl Physiol. 2009;107(4):1144–1155.
4. Kapil V, Khambata RS, Robertson A, Caulfield MJ, Ahluwalia A. Dietary nitrate provides sustained blood pressure lowering in hypertensive patients: a randomized, phase 2, double-blind, placebo-controlled study. Hypertension. 2015;65(2):320–327.
5. Gonzalez AM, Trexler ET. Effects of citrulline supplementation on exercise performance in humans: a review of the current literature. J Strength Cond Res. 2020;34(5):1480–1495.
6. Pérez-Guisado J, Jakeman PM. Citrulline malate enhances athletic anaerobic performance and relieves muscle soreness. J Strength Cond Res. 2010;24(5):1215–1222.
7. Maughan RJ, Burke LM, Dvorak J, et al. IOC consensus statement: dietary supplements and the high-performance athlete. Br J Sports Med. 2018;52(7):439–455.