BioRhythm Blue Cycle Review

Blue Cycle

Blue Cycle is non-stimulant pump-based pre-workout by BioRhythm which contains several well-established performance enhancers, though not at clinically effective levels…


Blue Cycle is non-stimulant pump-based pre-workout by BioRhythm which contains several well-established performance enhancers, though not at clinically effective levels…[Skip to the Bottom Line]


Citrulline is a precursor to the amino acid Arginine, which is a precursor to Nitric Oxide (NO). As demonstrated in a 2007 study, supplemental Citrulline is significantly more effective at raising plasma Arginine than supplemental Arginine itself.

The problem with supplemental Arginine is that it is metabolized in the intestines and liver into other substances such as Ornithine and Urea. The intestines and liver contain relatively high levels of Arginase, the enzyme that converts Arginine to Ornithine and Urea. As a result, very little goes on to be involved with the synthesis of NO because it is being diverted for other purposes. Citrulline, on the other hand, is able to bypass the liver and is metabolized into Arginine elsewhere, where not as much Arginase is present. Thus, more of the Arginine is able to convert into NO.

A 2002 study, published in the “British Journal of Sports Medicine” found that Citrulline Mallate supplementation (6g/day for 15 days) significantly increased ATP production during exercise in healthy adult males. A 2009 study, published in the “Journal of Free Radical Research”, found that 6 grams of Citrulline Malate given to male cyclists before a race increased “plasma Arginine availability for NO synthesis and PMNs priming for oxidative burst without oxidative damage”. A 2011 study, the subjects of which were rats, found that supplemental Citrulline increased muscular contraction efficiency (less ATP was required for the same amount of power), in-line with the findings of the above-mentioned human study.

Overall, Citrulline (at doses of around 6g) has multiple mechanisms of action by which it may effectively enhance exercise performance. Blue Cycle contains 1200mg of Citrulline Malate (800mg Citrulline 400mg Malic Acid), far less than the above mentioned scientifically validated dose of 6g.


Beta-Alanine is a precursor to the amino acid Carnosine (formed by combining Histidine and Beta-Alanine). Carnosine acts a lactic acid buffer, effectively delaying fatigue in the working muscle. Beta Alanine takes time to accumulate, but if taken over a sustained period of time (2+ weeks), can be an extremely effective ergogenic aid with a strong safety profile.

One study in particular that measured the Carnosine levels of sprinters found that individuals with higher muscular Carnosine levels exhibited higher power output in the latter half of a 30m sprint (because they had less lactic acid build-up). Multiple studies have confirmed that Beta Alanine supplementation increases muscular Carnosine in a dose dependent manner. In particular, a 2012 study published in “Amino Acids” found that subjects who consumed 1.6 or 3.2 grams of Beta Alanine daily experienced significant increases in muscle Carnosine in as little as two weeks, with the higher dose achieving a higher concentration of Carnosine.

Though Beta-Alanine supplementation has been demonstrated to increase acute-power output (1 rep max) in certain studies, the more reliable benefits lie in its ability to prolong endurance during high-intensity exercise (rowing, sprinting, weight-lifting, etc.). Blue Cycle contains 600mg of Beta-Alanine which, just as with Citrulline Malate, is far less than a scientifically validated dose. It is possible that there is some marginal benefit to this low dose of Beta-Alanine, but a dose this low would take much longer to cause muscle saturation.


L-Ornithine L-Aspartate is simply a combination of the amino acids Ornithine and Aspartic Acid, both of which have shown varying degrees of efficacy with regards to reducing muscular fatigue via reducing Ammonia build-up in the working muscle.

Ornithine is an amino acid used alongside Arginine and Citrulline in the Urea Cycle, the process by which Ammonia is metabolized into the harmless substance Urea. Prolonged exercise generally brings about increases in Ammonia, which causes fatigue in the working muscle after enough has built up. As evidenced in a 2010 study published in the European Journal of Clinical Nutrition, supplemental Ornithine, at a dose of 100mg/kg, has failed to influence fatigue in short duration exercise. However, a 2008 study from “Nutrition Research” noted a significant reduction in fatigue during prolonged exercise in healthy volunteers who consumed 2g Ornithine daily for 6 days and 6g prior to testing.

Unfortunately, the amount of Ornithine present in the Blue Cycle formula is extremely negligible and even at double, triple, or quadruple the dose, it likely wouldn’t reduce muscular fatigue to any meaningful degree.

Aspartic Acid has been touted as a performance enhancer for decades no, with preliminary research (in rats) suggesting that Aspartic Acid may help remove excess Ammonia during exercise, effectively reducing fatigue. Though some efficacy has been demonstrated, the overall results are mixed and not particularly promising. A 1964 study, published in the “American Journal of Physiology—Legacy Content”, failed to note any significant changes in various performance measures including breathing capacity and metabolic rate in exercising men who received 2 grams of aspartic acid (magnesium and potassium salts) over a 9 week period. A similar failure occurred in a 1983 study from the “International Journal of Sports Medicine” , this study using 6 gram, acute dosages. However, a 1988 study from “Research Quarterly for Exercise and Sport”, found that 10 grams of Aspartic Acid salts effectively increased time to exhaustion (cycling) in male athletes. This study also noted significant decreases in ammonia and lactate, indicating that this was the mechanism of action.

So, while different studies have yielded different results, it does appear that higher doses of Aspartic Acid may convey some anti-fatigue benefits during extended exercise. That being said, Pump HD contains just 1000mg of Aspartic Acid which unfortunately is far less than the minimum dose which has demonstrated this efficacy.

Unfortunately, given that the total amount of L-Ornithine L-Aspartate in the Blue Cycle formula is only 375mg, there is simply not enough of either of these two amino acids to convey meaningful performance enhancement benefits.


Alpha Lipoic Acid is a versatile anti-oxidant with variety of potential benefits, though within the context of Blue Cycle, BioRhythm appears primarily concerned with the cardio-vascular benefits. A 2005 study, the subjects of which were rats, found that Alpha Lipoic Acid treatment effectively reversed impairment of vasorelaxation in obese rats. A later (2010) study, published in “Experimental and Clinical Endocrinology & Diabetes”, replicated these findings in human subjects with Hypothyroidism. This has also been replicated in subjects with type 2 Diabetes, and impaired fasting glucose. Unfortunately, while these studies certainly lend credibility to the notion that Alpha Lipoic Acid can enhance blood flow in individuals with impaired blood flow, it can’t be definitively stated that it can enhance blood flow in normal, healthy subjects.


As mentioned in the Beta-Alanine section, Histidine is required to form Carnosine, and since it is an essential amino acid, it must be acquired through diet (or supplemented). However, while Histidine deficiency can certainly lead to Carnosine deficiency, supplemental doses of Histidine have proved ineffective at boosting muscle Carnosine above baseline, whereas Beta-Alanine is quite effective at doing so. While Histidine certainly doesn’t hurt, it does eat up some of the serving size which could better be allocated to an ingredient that actually provides benefit. Unfortunately, it appears BioRhythm didn’t do their homework on this one.


While the key ingredients of Blue Cycle certainly have the potential to enhance exercise performance via reducing fatigue, the formula suffers from one major flaw: it is extremely under-dosed. Not one ingredient found in the Blue Cycle formula is at a clinically effective dose and even two or three servings at once wouldn’t yield effective doses. Blue Cycle is quite possibly the most under-dosed pre-workout formula we’ve ever come across. At $1.75 per serving, Blue Cycle is also extremely over-priced given that the same formula could be easily reconstructed for less than 1/4th the cost. Ultimately, we cannot recommend Blue Cycle for those seeking a non-stimulant, anti-fatigue pre-workout supplement.

  1. Bendahan, D., et al. “Citrulline/malate promotes aerobic energy production in human exercising muscle.” British journal of sports medicine 36.4 (2002): 282-289
  2. Sureda, Antoni, et al. “Effects of L-citrulline oral supplementation on polymorphonuclear neutrophils oxidative burst and nitric oxide production after exercise.” Free radical research 43.9 (2009): 828-835.
  3. Giannesini, Benoît, et al. “Citrulline malate supplementation increases muscle efficiency in rat skeletal muscle.” European journal of pharmacology 667.1 (2011): 100-104.
  4. Sale, Craig, Bryan Saunders, and Roger C. Harris. “Effect of beta-alanine supplementation on muscle carnosine concentrations and exercise performance.” Amino acids 39.2 (2010): 321-333.
  5. Stellingwerff, Trent, et al. “Effect of two β-alanine dosing protocols on muscle carnosine synthesis and washout.” Amino Acids 42.6 (2012): 2461-2472.
  6. Wilson, Jacob M., et al. “Beta-alanine supplementation improves aerobic and anaerobic indices of performance.” Strength & Conditioning Journal 32.1 (2010): 71-78.
  7. Barnes, Richard H., et al. “Effects of exercise and administration of aspartic acid on blood ammonia in the rat.” American Journal of Physiology–Legacy Content 207.6 (1964): 1242-1246.
  8. Maughan, R. J., and D. J. M. Sadler. “The effects of oral administration of salts of aspartic acid on the metabolic response to prolonged dexhausting exercise in man.” International journal of sports medicine 4.02 (1983): 119-123.
  9. Consolazio, C. Frank, et al. “Effects of aspartic acid salts (Mg and K) on physical performance of men.” Journal of applied physiology 19.2 (1964): 257-261.
  10. Wesson, Matthew, et al. “Effects of oral administration of aspartic acid salts on the endurance capacity of trained athletes.” Research Quarterly for Exercise and Sport 59.3 (1988): 234-239.
  11. Demura, Shinichi, et al. “The effect of L-ornithine hydrochloride ingestion on performance during incremental exhaustive ergometer bicycle exercise and ammonia metabolism during and after exercise.” European journal of clinical nutrition 64.10 (2010): 1166-1171.
  12. Sugino, Tomohiro, et al. “L-ornithine supplementation attenuates physical fatigue in healthy volunteers by modulating lipid and amino acid metabolism.”Nutrition research 28.11 (2008): 738-743.
  13. Curis, Emmanuel, Pascal Crenn, and Luc Cynober. “Citrulline and the gut.”Current Opinion in Clinical Nutrition & Metabolic Care 10.5 (2007): 620-626.
  14. Heinisch, B. B., et al. “Alpha‐lipoic acid improves vascular endothelial function in patients with type 2 diabetes: a placebo‐controlled randomized trial.”European journal of clinical investigation 40.2 (2010): 148-154.
  15. Heitzer, Thomas, et al. “Beneficial effects of α-lipoic acid and ascorbic acid on endothelium-dependent, nitric oxide-mediated vasodilation in diabetic patients: relation to parameters of oxidative stress.” Free Radical Biology and Medicine31.1 (2001): 53-61.
  16. Lee, Woo Je, et al. “α-Lipoic acid prevents endothelial dysfunction in obese rats via activation of AMP-activated protein kinase.” Arteriosclerosis, thrombosis, and vascular biology 25.12 (2005): 2488-2494.
  17. Xiang, G. D., et al. “Alpha-lipoic acid improves endothelial dysfunction in patients with subclinical hypothyroidism.” Experimental and clinical endocrinology & diabetes 118.09 (2010): 625-629.
  18. Derave, Wim, et al. “β-Alanine supplementation augments muscle carnosine content and attenuates fatigue during repeated isokinetic contraction bouts in trained sprinters.” Journal of applied physiology 103.5 (2007): 1736-1743.
  19. Bishop, David, and Brett Claudius. “Effects of induced metabolic alkalosis on prolonged intermittent-sprint performance.” Medicine and science in sports and exercise 37.5 (2005): 759-767.
  20. Bishop, David, et al. “Induced metabolic alkalosis affects muscle metabolism and repeated-sprint ability.” Medicine and science in sports and exercise 36.5 (2004): 807-813.
  21. Kern, Benjamin, and Tracey Robinson. “Effects of beta-alanine supplementation on performance and body composition in collegiate wrestlers and football players.” Journal of the International Society of Sports Nutrition 6 (2009): 1-2.
  22. Dunnett, M., and R. C. Harris. “Influence of oral ß‐alanine and L‐histidine supplementation on the carnosine content of the gluteus medius.” Equine veterinary journal 31.S30 (1999): 499-504.

Click to comment
To Top