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Understanding Tibet’s Secret To Superhuman Performance
Cordyceps has been a standard ingredient for exercise performance since it first gained attention when researchers discovered Sherpas were making a special tea concoction with them. Studies demonstrated that cordyceps plays a critical role in allowing the body to adapt to high levels of physical stress, the kind of performance-under-duress that has earned Sherpas a reputation for amazing physical capabilities.
Despite their diminutive stature (most Sherpas average 5’5” and weigh around 140lb), these ultra-efficient climbers are capable of carrying up to 150lb in gear while climbing high-elevation peaks like Mount Everest, which summits at 29,032ft. These adaptations to hypoxia (lack of oxygen) led researchers to start testing cordyceps’ effects on elite endurance athletes.
Cordyceps is an adaptogenic herb that’s naturally cultivated in Tibet. It has multiple bioactive ingredients that work many ways with your body systems to improve overall functioning. It’s a major part of Optygen and OptygenHP, and largely responsible for their success. The complex effects it produces mean it’s hard to study, and how it works has often been misunderstood by non-Chinese researchers.
More recent research demonstrates that cordyceps has a wide scope of antistress actions that benefit key measures of exercise performance: aerobic capacity, cardiovascular functions, tissue oxygenation, time to exhaustion, VO2max, anaerobic threshold, energy generation efficiency, and overall endurance performance. Those studies also demonstrate that the key to reaching these benefits is to exercise at or near threshold – really pushing your limits – and to take cordyceps continuously. The effects accumulate gradually; cordyceps works with your body to adapt to and counteract exercise stress, culminating after 3-4 weeks and then maintaining with continued dosage.
In this blog post, we’ll show you exactly how older, less-effective studies on cordyceps and exercise performance missed the boat on their designs – and why those misses mean results were not always favorable. We’ll also explore why cordyceps has grown in popularity and remains a common ingredient for endurance products, including Optygen and OptygenHP, by citing the more effective, comprehensive research and studies that produced the effects summarized above.
Recent Advance #1: Identification
Cordyceps is a specialized fungus that infects and then slowly consumes specific underground caterpillars, replacing the caterpillar, then turning into a mushroom that pops up out of the ground. Think of cordyceps as a “trufflepillar” – a mushroom wrapped in caterpillar skin.
Turns out there are numerous affected caterpillar species and many types of cordyceps, but this was unknown until the boom in DNA technologies precisely nailed down the nuances of what cordyceps actually is. This led to Cordyceps sinensis being renamed into Ophiocordyceps sinensis, a name which nobody but scientists use, along with dozens of new species names. Now that we know what cordyceps is, we can acquire and label it accurately. Although the name has changed, the stuff in the pills is the same as always. We’ll use the generic term cordyceps throughout this blog.
(Citations for Cordyceps & Identity: Cheng 2016; Dong 2014, 2015; Hu 2013; Lee 2012; Liu 2015; Lo 2013; Zhang 2018)
Recent Advance #2: Cultivation
Cordyceps costs skyrocketed from increased TCM use, leaving only a small, expensive supply available to the global market. Fortunately, the cordyceps boom forced a solution: cultivation. Using the original TCM live mushrooms, commercial cordyceps production grew quickly without the need for caterpillars. The once-rare fungus is now produced just like the mushrooms you put on a salad. This little-known cordyceps fact has allowed a stable supply for both CM and global export since the 1990s.
Additionally, commercial cultivation is a clean process, removing the potential for allergenic bug parts, heavy metal contamination, counterfeiting, and seasonal variability of active agents. In fact, cultivated cordyceps has been shown to have more bioactive contents and stronger bioactivities compared to the original trufflepillar sources. Controlled production and DNA testing also mean that cordyceps supply today is verified down to the species, which is reflected on supplement facts of products. Guaranteed supply and guaranteed quality.
(Citations for Cordyceps & Cultivation: Cao 2015; Dong 2015; Lo 2013; Zhang 2018)
Recent Advance #3: New Research on Exercise Performance
Cordyceps is a well-researched topic, with that research comprising over 1,800 articles in PubMed, over 3,200 in cnki.net (China’s PubMed analog), over 4,545 in Europe PMC, and over 60,000 on Google Scholar as of September, 2021. Needless to say, cordyceps goodies have been identified and thoroughly tested to show their effects (see Table).
But what are those effects? Simply put, elements of cordyceps interact beneficially with normal control elements that run your body’s systems and functions, promoting full-body health. Because cordyceps’ beneficial molecules are closely related to ones your body uses routinely to maintain healthy functions, they can fill in any gaps or shortcomings. For example, cordycepin is a slightly altered adenosine molecule (the A in ATP). It interacts with adenosine receptors on blood vessels that control local circulation, improving blood flow and tissue oxygenation when needed.
The impact on endurance training is obvious, but early exercise studies on cordyceps were ill-designed for long-term exercise performance implications, essentially treating cordyceps like it was caffeine. Most did not take into account the multifaceted effects of cordyceps or the fact that it produces more pronounced effects over time in seriously stressed individuals. They also did not take into account the level of total body stress from exercise, which is more extreme for long-term endurance exercise. Lab exercise by cycle ergometry, treadmill, or weight machines in a non-competitive atmosphere while being poked and prodded is much different than long-term endurance racing events.
Most studies also did not last long enough to see effects from adaptogenic activities and/or did not use enough subjects to more easily show effects – and they often weren’t even observing the full suite of benefits. For example, the immune and recovery effects of cordyceps (and adaptogens more broadly), are not usually measured in routine lab exercise performance tests, but they’re undeniably critical for endurance athletes. This author published two reviews on adaptogens and exercise performance in 2000 and 2004 that clearly illustrated how studies with larger subject numbers and longer durations found benefits from adaptogens that were missed by smaller, less comprehensive studies.
Fortunately, recent research has taken that message to heart, and has repeatedly found performance benefits from defined cordyceps when subject numbers and/or duration and/or exercise stress were sufficient. Here’s the rundown on the new research, starting with the most relevant studies for strenuous, long-term exercise.
Figure 1: Improved Time to Exhaustion (TTE) for twelve long-distance runners taking either Placebo or Cordyceps sinensis (four grams powder – not an extract) for two weeks in a randomized, repeated measures, counterbalanced single-blind study by an intense, incremental treadmill running VO2max protocol (P<0.05). (Adapted from Thongsawang, 2021).
Figure 2: Improved aerobic capacity (VO2max) for twelve long-distance runners taking either Placebo or Cordyceps sinensis (four grams powder – not an extract) for two weeks in a randomized, repeated measures, counterbalanced single-blind study by an incremental treadmill running VO2max protocol (P<0.05). (Adapted from Thongsawang, 2021).
- Twelve male long-distance runners (~37y) were given cordyceps and placebo in a crossover design for two week periods. Time to exhaustion, VO2max, and anaerobic threshold in lab testing were significantly improved during the cordyceps period vs. placebo period (Thongsawang 2021).
- A relevant crossover study of seven male road cyclists given cordyceps for three months found improved testosterone/cortisol ratio and antioxidant activity after a long race compared to placebo period, suggesting increased protection against overreaching and overtraining syndrome (Rossi 2014).
- Thirty highly fit athletes were given either placebo or cordyceps for six weeks and tested for changes in exercise physiology. The cordyceps group increased cardiovascular and metabolic functions during exercise, but placebo did not, indicating more efficient exercise capacity (Nicodemus 2001).
- Eighteen male long-distance track athletes (~20 y) trained at altitude for two weeks and received either placebo or a cordyceps/rhodiola blend. The cordyceps blend significantly improved prolonged exhaustive run time after altitude training compared to baseline and placebo (+5.7% vs. 2.2%). The cordyceps blend also better prevented parasympathetic nervous system activity decline, which would help explain the adaptive benefits. Even though this study had low subject numbers and a short duration, the exercise stress was more relevant to endurance training (Chen 2014).
Studies on non-athletes or lightly active/newly training subjects showed similar findings:
- Twenty-eight recreationally active women and men (18-35y) consumed either placebo or a cordyceps mushroom blend for one week. After one week, the cordyceps group showed significant improvements in high-intensity cycle ergometry time to exhaustion (+28.1 sec), but VO2max and anaerobic threshold were not significantly changed. Ten subjects continued out to three weeks and results improved even more for the cordyceps group – +68.9 seconds in time to exhaustion and improvements in VO2max and anaerobic threshold. This study showed that longer study duration demonstrates increasing long term results from cordyceps (Hirsch 2017).
- This study used two different groups of recreationally active women and men (19-34y) for a placebo-controlled comparison of a cordyceps mushroom blend on typical cycle ergometry testing and a Wingate anaerobic power test for peak power. One group received a low dose (1-2 g/d) across a longer term (28d); the other received a high-dose (12g) for a shorter term (7d). Time to exhaustion was significantly improved from baseline for the low-dose/long-term cordyceps group, and showed a trend (p=0.07) vs. placebo. VO2max was significantly improved from baseline, but the placebo group showed no change. Lactate levels showed a corresponding decline in the cordyceps group. The high-dose/short-term trial showed few differences between cordyceps and placebo groups. This study emphasized the need for longer duration and long-term exercise stress being necessary to show benefits for cordyceps, a classic adaptogen response. Clearly, longer times and longer exercise durations benefit more from cordyceps. Dose is less important, another characteristic of adaptogens (Dudgeon 2018) .
- Thirty-six healthy, sedentary males were given either placebo or cordyceps for two weeks and embarked on aerobic exercise training. Exercise capacity was increased by cordyceps vs. placebo, as were beneficial responses to systemic stress (Nagata 2006).
- Another crossover study of 14 healthy males (~20y) given cordyceps and rhodiola for seven days while starting a running training program showed higher muscle glycogen resynthesis immediately after exercise on day seven mediated by insulin and fat oxidation, indicating improved exercise recovery (Tsai 2019).
- Healthy subjects (131 between 40-70y) were given either placebo or cordyceps for 12 weeks. Endurance performance (+4.1%), aerobic capacity, and exercise metabolism were significantly improved from baseline, whereas placebo group changes were not significant or worsened (Zhu 2001, 2004).
- Similarly, 37 healthy elderly Chinese were given either cordyceps or placebo for six weeks. VO2max, aerobic capacity, anaerobic threshold, and resistance to fatigue were improved from baseline by cordyceps but not by placebo (Xiao 1999, 2004; Yi 2004).
- Twenty untrained subjects aged 50-75y were divided into placebo and cordyceps groups. Exercise testing for aerobic capacity was done before and after 12 weeks, but subjects did not change their lifestyle habits. Although VO2max was unchanged in both groups, the cordyceps group increased their metabolic threshold and ventilatory thresholds significantly. The placebo group did not (Chen 2010).
- Eighty healthy subjects were given either cordyceps or placebo for eight weeks. NK-cell activity was increased significantly more by cordyceps (Jung 2019).
- Similar results were found for 70 healthy male adults given Cordyceps militaris (as in Optygen) for four weeks (Kang 2015).
Interestingly, eight studies with durations under eight weeks and fewer than 24 subjects who were sedentary or just starting a training program did not show consistent, significant benefits from cordyceps compared to a placebo (Buchanan 2011; Colson 2005; Earnest 2004; Herda 2008; Hsu 2011; Kreipke 2020; Liao 2019; Parcell 2004), although some showed statistical trends in favor of cordyceps for certain physiological changes (Kreipke 2020; Liao 2019).
To determine if a low subject number was a factor for not finding benefit from cordyceps on exercise, a Fisher’s Exact Test 2X2 Contingency Table for Any Positive or All Null results from studies with 24 or less subjects or more than 24 subjects was performed. Analysis showed that significant benefits were found with high statistical significance (P<0.0001) for studies with more than 24 subjects. No studies with 24 or more subjects did not find significant benefits from cordyceps. In other words, cordyceps studies on exercise performance or parameters with fewer than 24 total subjects have a difficult time finding beneficial effects because of inadequate subject numbers. Scientists call this a Type II Error – missing a true difference between groups because there aren’t enough subjects.
(Citations for Cordyceps & Exercise Performance: Bucci 2000, 2004; Buchanan 2011; Chen 2010; Chen 2014; Colson 2005; Earnest 2004; Herda 2008; Hirsch 2017; Hsu 2011; Jung 2019; Kang 2015; Kreipke 2020; Liao 2019; Nagata 2006; Nicodemus 2001; Parcell 2004; Rossi 2014; Thongsawang 2021; Tsai 2019; Xiao 1999, 2004; Zhu 2001, 2004)
Adding the centuries of traditional cordyceps use to modern clinical studies of sufficient statistical power affirms the benefits from continuous use of cordyceps (sometimes with other adaptogens like rhodiola) for exercise performance and metabolism. Many animal and in vitro studies have found specific mechanisms of actions for cordyceps that explain why it has benefits for ameliorating exercise stress, but we’ll spare the details for now.
What can you expect from taking cordyceps if you are an endurance exercise athlete? Remember that the key to using herbal adaptogens is longer, not more. As continued research has shown us, cordyceps is not like caffeine – it does not have physical effects immediately after taking it. Instead, somewhere in a 1-2 weeks period of heavy training and/or competing, you might notice you feel better, perform better, and recover better. You should see a steady improvement to a new plateau of performance and recovery after 4-8 weeks, with maintenance or even some improvements thereafter.
These timelines appear to be typical for combinations of adaptogens (rhodiola plus cordyceps, for example), as all adaptogens work similarly with subtle differences in their molecular action mechanisms. You might notice other fringe benefits for your health – mental, gastrointestinal, hormonal, and immune effects are also evidenced by adaptogens but not fully considered here.
Finally, dose is less important than continuous ingestion during times of continuous exercise stress. That said, a total daily dose of around 3,000mg of adaptogens matches almost all of the scientific literature for beneficial results for strenuous exercise. Adaptogens, including cordyceps, are there for your body to use to encourage your body to adapt and thrive.
If you’d like to continue learning, we suggest reading about, Cyclic Cluster Dextrin: A Superior Carbohydrate For Endurance.
|Cerebrosides (aminoethanol-sugar-fatty acid complexes)||Membrane functions, Neuroprotective|
|Cordycepic acid (a form of D-mannitol)||Antioxidant, Cytokines expression|
|Cordycepin (3’-deoxyadenosine)||Circulation, oxygen delivery, Cell receptors interactions (Controls)|
|Nucleotides (Adenosine, Guanine)||Antifatigue, ATP, DNA & RNA precursors, Circulation, Organ protective functions|
|Polysaccharides (Glucans, cordyglucans, galactomannans & conjugates)||Antifatigue, Antioxidant, Apoptosis, Cytokines expression, Glucose-related enzymes activation, Esterases inhibitor, Hormonal interactions, Immunomodulation|
|Sterols (ergosterol) & epoxysterols||Hormonal interactions, Organ protective functions|
|Epoxy sterols||Hormonal interactions|
From Chiu 2016; Das 2021; Dong 2015; Lee 2012; Lo 2013; Yan 2014
Fisher’s Exact Test for 2X2 Contingency Tables: P<0.0001
Studies with more than 24 total subjects find significant changes from Cordyceps, but only 21% of studies with less than 24 subjects found significant effects of Cordyceps. Null hypothesis is that there is no difference between placebo and active groups. The P value of 0.05 or less indicates there is not no difference, and the null hypothesis is rejected, meaning there is a difference between groups.
American College of Traditional Chinese Medicine (ACTM). What is Chinese medicine? Accessed Sep 2021 (https://www.actcm.edu/chinese-medicine )
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