Cordyceps for Exercise Performance: Scientific Evidence Explained

These mushrooms that invade insect bodies haven’t only inspired The Last of Us. In recent years, cordyceps have also become a popular supplement in fitness circles. Brands market them as a natural way to boost stamina, energy, and recovery, and some fitness influencers echo that.

In this article, I’ll briefly walk you through what looks promising, what’s still unclear, and where the evidence falls short.

What are cordyceps?

Cordyceps are a group of parasitic fungi that have been used in East Asian medicine for centuries, often as tonics or adaptogens.

The most historically used species is Cordyceps sinensis. In the wild, it grows on caterpillars in high-altitude regions of the Himalayas. According to traditional stories, local herders noticed that animals grazing on it seemed stronger and more energetic, and over time began using cordyceps themselves as a remedy for vitality, endurance, and libido.

Wild C. sinensis is rare and expensive (in fact, it is among the most expensive mushrooms in the world), so most supplements use cultivated versions grown in labs. A common alternative is Cordyceps militaris, which is much easier (and cheaper) to grow and has become increasingly common in modern products. In the EU, Cordyceps sinensis is authorized for use in foods and supplements, while C. militaris is not.

Today, cordyceps are typically sold as powders, capsules, tinctures, or as part of supplement blends. The marketing usually mentions benefits such as endurance, fatigue resistance, immune support, and recovery.

What is exercise performance?

In this article, ‘exercise performance’ mainly refers to two outcomes researchers often measure:

1. Endurance performance. How long or how hard someone can exercise before fatigue forces them to stop. Common measures include time to exhaustion (how long you can keep going) or time-trial performance (how fast you complete a set distance).
2. Aerobic capacity. Usually measured as VO₂max, which reflects the maximum amount of oxygen your body can take in and use during intense exercise.

Can cordyceps improve exercise performance?

Cordyceps contain bioactive compounds such as cordycepin, adenosine-like compounds, and polysaccharides (including beta-glucans). In cell and animal studies, these compounds have been linked to biological pathways that could influence exercise performance.

Preclinical research suggests cordyceps may help muscles use oxygen more efficiently and support cellular energy availability, which could, in theory, allow exercise at higher intensities for longer. Some studies also point to effects on blood flow, inflammation, and immune function, all of which could support recovery between training sessions.

As is often the case, however, translating these mechanisms into real-world performance gains in humans has proven less straightforward.

Are cordyceps an effective pre-workout?

If pre-workout means a supplement taken shortly before training for an acute boost, the honest answer is that we don’t really know.

While this kind of use gets mentioned in fitness discussions, there’s currently no solid clinical evidence testing an acute pre-workout effect.

Mixed signals from long-term human studies

Most available research looks at longer-term supplementation, typically over weeks or months.

For athletes

In well-trained young adults, results are inconsistent.

One randomized controlled trial in 22 endurance-trained cyclists found no improvements in aerobic capacity or endurance performance after five weeks of cordyceps supplementation.

Another clinical trial in 22 trained marathon runners reported improved 5-kilometer run times after 12 weeks compared with placebo, even though VO₂max remained unchanged.

For older adults

A similar pattern appears in older adults.

In a longer-term pilot controlled trial, 12 weeks of supplementation improved measures of submaximal exercise performance, but again, aerobic capacity (VO₂max) did not improve. Whether this reflects the duration of supplementation, differences between populations, or other factors isn’t clear.

For moderately active individuals

In recreationally active adults, two short-term studies using mushroom blends that included cordyceps reported improvements in endurance performance and VO₂max after three and four weeks. However, the first study was extremely small, and the effects across both trials were modest.

Because these products were blends, it’s impossible to know whether any improvements came from cordyceps or from other ingredients. Both studies were also funded by supplement companies, which adds another layer of uncertainty.

Why the evidence is hard to pin down

Taken together, it’s still hard to draw clear conclusions. Any potential effects may depend on who is taking the supplement, how long they take it, and how trained they already are. Well-trained athletes, for example, typically have less room for improvement than less-trained individuals.

On top of that, most studies are small and difficult to compare, as they use different species, formulations, doses, and populations. Training itself is another confounding factor, since participants usually continue exercising during the study.

Another important factor (and a painful problem in scientific research) is publication bias. Studies with positive findings are more likely to be published than those showing no significant differences, which can create an exaggerated and overly optimistic picture of how effective a supplement actually is.

For example, one review on fungal supplements reported favorable outcomes in 13 of the 14 included studies — a level of consistency that’s rather unlikely and points to bias. Although the review included a section on cordyceps and reported improvements in performance outcomes, those conclusions rested on barely statistically significant results from just two small studies, pooling only 24 participants, with one judged to have a high risk of bias.

None of these rules out potential benefits. But for now, it does suggest that overly confident claims are running ahead of the evidence and invites a more cautious optimism rather than hype.

Safety

Cordyceps supplements are generally reported as well-tolerated in human studies, though some research has noted mild side effects such as gastrointestinal discomfort, headache, or dry mouth.

As with most supplements, product quality can vary widely, including the species used, how the product is grown and processed, and the concentration of bioactive compounds. Because cordyceps supplements are not yet standardized, there’s still no clear consensus on which formulations or doses, if any, are optimal.

It’s always a good idea to consult a healthcare professional before starting a new supplement, especially if you have underlying health conditions, are pregnant, or take medications.

Final thoughts

As of today, there are no authorised health claims for cordyceps improving exercise performance in the EU Register of Nutrition and Health Claims.

While there are valid biological reasons to think cordyceps could influence exercise performance in theory, the clinical evidence just isn’t there yet to support strong conclusions.

However, this doesn’t mean cordyceps don't work at all. Some studies do report positive effects, and hopefully, that will inspire more robust independent research. For now, the most honest answer is a cautious maybe.