Xtend Elite Features 2g PeakO2 with New Research!

Before training, many of us are religious when it comes to taking pre-workouts. But, how often do we find ourselves drained, halfway through the day’s workout, in need of a little bit of an endurance boost?

Xtend Elite

Xtend Elite is the PeakO2-powered version of Xtend for endurance athletes!

That’s exactly why companies sell intra-workout supplements. They’re supposed to help reduce fatigue in the gym, and improve your performance. Intra-workouts give you the stuff you need to maximize each and every rep, whether you’re on the first exercise or last exercise!

Xtend, fresh off a bold rebrand, knows how important intra-workout supplementation is. It’s exactly why they’ve carried over one of their best products, Xtend Elite, which is packed with effective ingredients. From branched-chain amino acids to PeakO2 (a power-maximizing blend with new research recently published), Xtend Elite has got you covered.

Xtend Elite replaces Xtend Perform, which was the first supplement launched with PeakO2. We quickly noticed some very interesting effects – such as lower heart rate, and more information has come out on the cordyceps-powered blend since then. Additionally, many of our readers have latched on, noticing inferior endurance when getting off of the cordyceps-based blend!

Something special is happening here, but now we need to discuss the updated Xtend Elite. Below, we break down the label, elaborate on PeakO2, and tell you just how everything in Xtend Elite will help you get the most out of your training.

Before we get into all of that, be sure to check out prices on PricePlow, and sign up for new deals and price drop alerts:

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PeakO2 is a research-backed performance-enhancing extract of several mushroom varieties what will significantly boost endurance.

Let’s start slightly out of order, focusing on the big difference-maker here, PeakO2. The BCAAs are listed below, but many of you know about them. Here’s what’s different:

  • PEAKO2 Performance Blend – 2000mg

    PEAKO2 is a medicinal mushroom blend that has been gaining steam in the supplement industry. Led by Cordyceps militaris, PEAKO2 has been shown to maximize power output and support oxygen uptake. That sounds great, but just how valid are those claims? As it turns out, the science backs it up!

    Xtend Elite Ingredients

    Xtend Elite has Xtend’s traditional 7g BCAA, but also endurance boosters in PeakO2, beta alanine, glutamine, ashwagandha, and a lot of citrulline malate!

    Cordyceps leading the way…

    Cordyceps militaris has a long list of anecdotal uses and benefits, but in recent years concrete evidence has been published. In 2016, researchers concluded that chronic use of a mushroom blend containing Cordyceps militaris “may be an effective method for enhancing aerobic performance and delaying fatigue by improving oxygen kinetics” in trained athletes.[6] These results are extremely encouraging, particularly as the blend used in the study was none other than PEAKO2! The athletes in the study saw significant increases in VO2 max, endurance, and peak power output.[6] It’s worth noting, however, that these subjects were consuming 4g of this blend daily for three weeks. But, even though Xtend Elite contains 2000mg, new research says that there are still benefits to be had!

    Lower dose, still significant endurance enhancement

    In 2017, researchers from the College of Charleston compared two different methods of supplementing with PEAKO2. Trial 1 used a 2g daily dose for 28 days (compared to placebo), whereas Trial 2 used a daily 12g dose for 7 days (compared to placebo). The low-dose, 28-day group saw significant decrease in time to fatigue, significant increase in VO2 max, and significant decrease in blood lactate levels.[7] The high-dose group saw similar results, in addition to decreases in submaximal heart rate and improved peak power output, akin to the results found in the study previously mentioned in the above section. This lends some credibility to a “high-dose loading phase” prior to an event like a weightlifting competition.

    PeakO2 Benefits

    2g/day of PeakO2 helped bring blood lactate down for athletes after 4 weeks of supplementation

    These tests were also conducted on individuals with “recreationally active adults”,[7] who were by no means elite athletes. They had less aerobic fitness than a trained athlete, which should be considered when analyzing these results. Nonetheless, these findings prove that the 2g dose of PEAKO2 in Xtend Elite is sufficient for athletes on a lesser budget!

    While PEAKO2 has other mushrooms (Reishi, King Trumpet, Shiitake, Lion’s Mane, and Turkey Tail) all the research points to Cordyceps militaris being the star of the show here – and that’s what’s first in the formula. The blend provides potential power and endurance enhancement, and works synergistically with the rest of this label. We absolutely love this stuff, and would be thrilled to see PEAKO2 continue its rise to prominence within the supplement industry!

    For more details, check out our updated Cordyceps blog post titled “The Cordyceps Crackdown: Hit-or-Miss in Supplements.. Until PeakO2!”.

  • L-Leucine – 3500mg

    But of course, this is an Xtend product, which means you’re guaranteed 7g BCAA per serving! Xtend Elite is first and foremost a BCAA supplement, remember.

    PeakO2 Benefits

    PeakO2 has several benefits for hard-training athletes, especially those who need a bump of endurance

    The brained-chain amino acids are the primary building blocks of protein, and are imperative in building muscle. L-leucine is the most anabolic of the 3 BCAAs, as it’s directly responsible for triggering muscle protein synthesis.[1] It also is key in activation of mTOR, which is the process that helps speed up muscle protein synthesis.[1] In other words, if you’re trying to build/maintain muscle, you’re going to want leucine around!

    BCAAs are commonly offered in the traditional 2:1:1 ratio, and that’s exactly what we see here. We’re getting 3500mg of leucine, and 1750mg of isoleucine and valine, each. This ratio has been shown to increase recovery, decrease rest periods between sets, and elevate potential fat oxidation.[2,3]

  • L-Citrulline Malate (1:1) – 3000mg

    Next up on the label is L-citrulline malate, and it fits in perfectly in this endurance-minded intra-workout supplement. Citrulline malate is citrulline mixed with malic acid (on a 1:1 ratio as implied in the subheading above), and acts as a “pump-inducer”. It’s been shown to improve blood flow, by way of increasing blood arginine levels.[4] In fact, supplemental citrulline malate is better at boosting arginine levels than arginine supplements themselves. Citrulline malate helps blood circulate, meaning oxygen and nutrients will get to your muscles faster when used during training!

    The Citrulline Pathway

    The Citrulline Pathway – This is how you get more arginine and then more nitric oxide

    One particular study cites that citrulline malate actually enhances amino acid utilization,[5] which bodes well for keeping endurance levels high during training. This same study also found higher growth hormone levels in subjects using citrulline malate supplementation, but do state that rigorous training is a key factor, as well.

    Xtend Elite packs a solid 3000mg dose per serving. While 6000-8000mg is the clinical dose, there’s a great chance that you’re getting far more in your pre workout, which is most common. This is a monster dose for an intra workout, so you’re still likely to see some of the aforementioned benefits – especially if there’s any citrulline in your pre!

  • L-Glutamine – 2500mg

    A conditional amino acid, L-glutamine is mostly found in meat, eggs, and milk-derived proteins. Mistakenly seen as a key muscle-building ingredient, glutamine is here for one thing – endurance.

    During prolonged exercise, blood ammonia concentrations rise, which is a direct precursor for fatigue. Research has shown that supplementing with glutamine can help lower blood ammonia levels, effectively improving endurance.[5]

    PeakO2 Ingredients

    PeakO2 has six different mushroom species, but the primary one is Cordyceps Militaris

    At 2500mg, Xtend is delivering a quality dosage of this endurance-enhancer. Working in tandem with the rest of the label, glutamine is definitely going to help keep you performing at your best while in the gym!

  • L-Isoleucine & L-Valine – 1750mg each

    Rounding out the three BCAAs included in Xtend Elite are isoleucine and valine, dosed to maintain the 2:1:1 BCAA ratio that has been studied extensively in research. Isoleucine isn’t as synonymous with muscle protein synthesis as leucine, but it does significantly increase glucose uptake and glucose usage.[8,9] Valine, in isolation, doesn’t seem to be very effective. However, when taken in conjunction with the other BCAAs, it helps round out the anti-catabolic effects a BCAA supplement offers.

  • CarnoSynⓇ Beta-Alanine – 1600mg

    PeakO2 is great for endurance, but we’re not done yet! We still have the most popular endurance-based amino!

    CarnoSynⓇ is a trademarked beta-alanine compound from Natural Alternatives International, Inc. This company has been extremely proactive in funding research to test their product, proving beta-alanine to be a highly effective chemical.

    CarnoSynⓇ has been shown to increase athletic performance (by increasing skeletal muscle carnosine concentrations),[10] increase work capacity,[11] delay fatigue,[12] and increase peak power output.[13]

    Beta Alanine Boosts Exercise Performance

    Beta Alanine Boosts Exercise Performance when taken 3.2g per day (but that was split amongst four separate doses)

    Beta-alanine is among the most studied, and proven, training supplements on the market. It turns into molecule carnosine in the body, where it offers protection from lactic acid build-up, which occurs during physical activity.[14] Beta-alanine has repeatedly been proven to be a potent enhancer of muscular endurance,[14,15] and has potential to reduce body fat due to its ability to increase training capacity.[16]

    While most studies recommend a dosage between 2 to 5g, we still think 1.6g of beta-alanine here is satisfactory because of everything else aiding endurance and combating fatigue in this product! Plus, just like citrulline malate, there’s a good chance you’re getting the other “half” of your dosage in your pre workout as well!

  • Electrolyte Blend – 1140mg

    Xtend makes sure to throw in some electrolytes (sodium citrate, potassium chloride, sodium chloride) to help you stay hydrated during training. We’re not going to go into too much detail here, but we will always take a little extra hydration, mainly because it helps keep your performance levels high!


    Interested in other novel ingredients from Compound Solutions? Dynamine (methylliberine) is a caffeine derivative that’s touted to be a faster-acting theacrine (TeaCrine).

    Athletic performance drops with as little as 2% dehydration, and with your loss of water comes a loss of electrolytes and minerals. A lack of electrolyte ions means a lack of electrical energy transfer, which means a lack of performance. Beating out those sports drinks, Xtend Elite adds quite a nice dose of them, and doesn’t shy away from the potassium (whose taste is tougher to cover) like other companies. Xtend being the flavor kings takes on the added salts and electrolytes and cordyceps (and Ashwagandha below) with ease!

  • SensorilⓇ Ashwagandha (Withania somnifera) root and leaf extract – 125mg

    Ashwagandha has long been touted as an effective supplement to treat stress and depression. The medicinal herb has shown to reduce cortisol levels, the hormone which the body excretes in stressful situations.[17] While exercising, you put your body under large amounts of stress. Thus, proactively defending your body from high cortisol levels may be conducive to better workouts.

    Ashwagandha has also been associated with “significant increases in muscle mass and strength” when used in tandem with resistance training,[18] but subjects in this study received a much larger dose of 600mg per day. While we don’t have that much here, this herb still may enhance your gains because it helps keep cortisol levels low!

    Long story short is that we’ll take ashwagandha anytime we can get it. It doesn’t taste the best, but we leave it to the flavor experts at Nutrabolt / Xtend to dominate it.

    If you find yourself feeling a bit “better” when taking Xtend Elite, you may wish to go further down the Sensoril / Ashwagandha rabbit hole – you will like what you discover on this herb.

Xtend Elite – be at the top of your game longer!

At some point, we’ve all found ourselves exhausted long before a workout is over. Rather than make our training more arduous than it already is, why not utilize an intra-workout supplement for some “late-inning” relief? Xtend Elite is like a top-level baseball closer – you call on it to come in late in the game and win the game.

Xtend Elite PeakO2

Don’t fear the cordyceps in PeakO2 – Xtend Elite comes in two amazing flavors!

When you consistently find yourself struggling through your training sessions, this is exactly what you want to have in your arsenal. It packs a hefty dose of BCAAs to refuel your muscles, citrulline malate for intra-workout pumps, and CarnoSynⓇ for muscular endurance. But, where Elite really separates itself is its inclusion of PEAKO2. This powerful mushroom blend, led by Cordyceps militaris, has been proven to boost both endurance and VO2 max. If taken long enough, you may even find increased power output. Who doesn’t want any of that?!

With all of that going on, we think Xtend Elite is a great intra-workout supplement. While BCAAs aren’t as effective as full-spectrum EAAs in building muscle, they do have both anti-catabolic and endurance properties. BCAAs are also famously easier to flavor than EAAs, and given Xtend’s track record, we’d bet this stuff tastes great!

Xtend Elite is an exceptionally formulated endurance supplement, as everything on the label works collectively together. You’ll find yourself feeling fresher, later on in your workout. Being able to perform better later into your workout, we have no doubt that this stuff will help you get the most out of your training!

Xtend Elite: Deals and Price Drop Alerts

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Disclosure: PricePlow relies on pricing from stores with which we have a business relationship. We work hard to keep pricing current, but you may find a better offer.

Posts are sponsored in part by the retailers and/or brands listed on this page.

About the Author: Mike Roberto

Mike Roberto

Mike Roberto is a research scientist and water sports athlete who founded PricePlow. He is an n=1 diet experimenter with extensive experience in supplementation and dietary modification, whose personal expertise stems from several experiments done on himself while sharing lab tests.

Mike's goal is to bridge the gap between nutritional research scientists and non-academics who seek to better their health in a system that has catastrophically failed the public. Mike is currently experimenting with a low Vitamin A diet.

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  2. Wiśnik, P, et al; “The Effect of Branched Chain Amino Acids on Psychomotor Performance during Treadmill Exercise of Changing Intensity Simulating a Soccer Game.”; Current Neurology and Neuroscience Reports; U.S. National Library of Medicine; Dec. 2011; https://pubmed.ncbi.nlm.nih.gov/22050133
  3. Blomstrand, E, et al; “Influence of Ingesting a Solution of Branched-Chain Amino Acids on Perceived Exertion during Exercise.”; Current Neurology and Neuroscience Reports; U.S. National Library of Medicine; Jan. 1997; https://pubmed.ncbi.nlm.nih.gov/9124069
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  7. Wesley David Dudgeon, Dennison David Thomas, William Dauch, Timothy Paul Scheett, and Michael John Webster; “The Effects of High and Low-Dose Cordyceps Militaris-Containing Mushroom Blend Supplementation After Seven and Twenty-Eight Days”; American Journal of Sports Science; 2018; 6(1): 1-7; https://article.sportssciencejournal.org/pdf/10.11648.j.ajss.20180601.11.pdf
  8. Doi, M, et al; “Isoleucine, a Potent Plasma Glucose-Lowering Amino Acid, Stimulates Glucose Uptake in C2C12 Myotubes.”; Current Neurology and Neuroscience Reports; U.S. National Library of Medicine; 26 Dec. 2003; https://pubmed.ncbi.nlm.nih.gov/14651987
  9. Doi, M, et al; “Isoleucine, a Blood Glucose-Lowering Amino Acid, Increases Glucose Uptake in Rat Skeletal Muscle in the Absence of Increases in AMP-Activated Protein Kinase Activity.”; Current Neurology and Neuroscience Reports; U.S. National Library of Medicine; Sept. 2005; https://pubmed.ncbi.nlm.nih.gov/16140883
  10. Hill, C. A., et al. “Influence of β-Alanine Supplementation on Skeletal Muscle Carnosine Concentrations and High Intensity Cycling Capacity.” Amino Acids, vol. 32, no. 2, 28 July 2006, pp. 225–233, doi:10.1007/s00726-006-0364-4. https://pubmed.ncbi.nlm.nih.gov/16868650/
  11. Stout JR, et al; “Effects of twenty-eight days of beta-alanine and creatine monohydrate supplementation on the physical working capacity at neuromuscular fatigue threshold”; J Strngth & Cond Resrch; 2006 20(4): 928−931; https://pubmed.ncbi.nlm.nih.gov/17194255
  12. Smith A E, et al; “The effects of beta-alanine supplementation and high-intensity interval training on neuromuscular fatigue and muscle function”; Eur J Appl Physiol; 2009; 105: 357−363; https://pubmed.ncbi.nlm.nih.gov/18989693
  13. Van Thienen R, et al; “Beta-alanine improves sprint performance in endurance cycling”; Medicine & Science in Sports & Exercise; American College of Sports Medicine; 2009; https://pubmed.ncbi.nlm.nih.gov/19276843
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  15. Stout, J R, et al; “Effects of Beta-Alanine Supplementation on the Onset of Neuromuscular Fatigue and Ventilatory Threshold in Women.”; Current Neurology and Neuroscience Reports; U.S. National Library of Medicine; 2006; https://pubmed.ncbi.nlm.nih.gov/17136505
  16. Kern, B D, and T L Robinson; “Effects of β-Alanine Supplementation on Performance and Body Composition in Collegiate Wrestlers and Football Players.”; Current Neurology and Neuroscience Reports; U.S. National Library of Medicine; July 2011; https://pubmed.ncbi.nlm.nih.gov/21659893
  17. Auddy, Biswajit, et al; “A Standardized Withania Somnifera Extract Significantly Reduces Stress-Related Parameters in Chronically Stressed Humans: A Double-Blind, Randomized, Placebo-Controlled Study”; JANA, Vol. 11, No. 1; 2008; https://blog.priceplow.com/wp-content/uploads/2014/08/withania_review.pdf
  18. Wankhede, Sachin, et al; “Examining the Effect of Withania Somnifera Supplementation on Muscle Strength and Recovery: a Randomized Controlled Trial.”; Journal of the International Society of Sports Nutrition; vol. 12, no. 1; 2015; https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4658772/

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