Cordyceps Supplements: Athletic Performance Claims and Study Findings

What Cordyceps Studies Actually Show About Athletic Performance

Editorial Notice: This article is for educational purposes only. It is not medical advice. Consult a qualified healthcare provider before starting any supplement, especially if you take medication or have a heart or lung condition.

By the TopShelfMushrooms Research Desk

Human trials on cordyceps and exercise are small, short, and inconsistent. Some studies in older adults and recreationally active people have found modest improvements in oxygen use and exercise thresholds. Trials in already-trained athletes have found little to nothing. Whether a study finds a benefit depends heavily on who was tested, how long they took it, and which measurement the researchers chose to report.

The Government’s Own Sports-Supplement Review Skips Cordyceps Entirely

Here’s a fact worth knowing before you read a single marketing claim: the NIH Office of Dietary Supplements’ fact sheet on exercise and athletic performance supplements reviews more than 20 ergogenic ingredients — caffeine, creatine, beta-alanine, beetroot juice, HMB, iron, protein, and others. Cordyceps is not one of them.

That’s not proof cordyceps doesn’t work. It means the federal government’s main consumer resource on sports supplements hasn’t judged the evidence substantial enough to include it in its review, unlike better-studied ingredients such as creatine and caffeine. Worth noting separately: the National Center for Complementary and Integrative Health does not currently maintain a standalone fact sheet on cordyceps within its Herbs at a Glance series, which covers roughly 50 other botanicals. So the most detailed picture of cordyceps and exercise comes from the individual published trials themselves, not a government evidence summary.

Three Human Trials, Three Different Stories

Setting marketing language aside, here’s what peer-reviewed human research has actually found.

• Older adults, 12 weeks: A 2010 double-blind, placebo-controlled trial gave 20 healthy adults aged 50 to 75 a fermented Cordyceps sinensis product (Cs-4) or a placebo for 12 weeks. The cordyceps group’s metabolic threshold rose 10.5% and ventilatory threshold rose 8.5% — both measures of how much exercise the body can handle before it starts accumulating lactate. Maximum oxygen consumption (VO2max) did not change in either group.
• Young, recreationally active adults, 1 and 3 weeks: A 2017 randomized, double-blind trial gave 28 adults (average age 23) a Cordyceps militaris mushroom blend or a placebo. Time-to-exhaustion on a cycling test improved after just one week and improved further after three weeks. VO2max and ventilatory threshold, however, only showed a measurable improvement after the full three weeks of supplementation, not after one.
• Trained NCAA rowers, single dose: A 2024 crossover study gave nine Division I collegiate rowers a single 1,500 mg dose of Cordyceps militaris powder or a placebo before a submaximal cycling test. Oxygen cost of cycling was modestly lower with cordyceps, but the sample was very small and the effect was measured only immediately after a one-time dose.

All three are legitimate, published, placebo-controlled trials. All three also used different populations, different durations, and different outcome measures — which is exactly why headlines about cordyceps and performance can sound contradictory even when no one is lying.

Why the Results Don’t Line Up

A few design differences explain most of the disagreement between studies:

• Training status: Sedentary and moderately active people generally have more room to improve, so effects show up more easily in those groups than in already well-conditioned athletes.
• Duration: The clearest improvements in VO2max and ventilatory threshold across these trials showed up after three weeks or more, not after a single dose or a few days.
• Species and dose: Older research mostly used fermented Cordyceps sinensis (Cs-4), while newer trials mostly use cultivated Cordyceps militaris. Doses, extraction methods, and whether the product is a single ingredient or a blend all vary between studies.
• Which outcome got measured: A study can report a real, statistically significant change in one measure (like time-to-exhaustion) while finding no change in another (like VO2max) in the very same participants. Reading only the headline result can make a mixed finding look like a clean win or a clean failure.
• Sample size: These trials range from 9 to 28 participants. Small samples make it easier for a real-but-modest effect to miss statistical significance, and easier for a fluke result to look meaningful.

A Quick Checklist for Reading Any Cordyceps Performance Claim

1. Does the claim name a specific study, or just say “studies show”?
2. Was the study done in people, in mice, or in lab cell cultures?
3. How many people were in it, and for how long did they take it?
4. Which outcome improved — VO2max, time-to-exhaustion, a threshold measure, or something else? A study can show one improvement without showing all of them.
5. Was it Cordyceps militaris or Cordyceps sinensis, and at what dose?
6. Were the participants trained athletes, recreational exercisers, or older sedentary adults? Results in one group don’t automatically apply to another.

Extra Caution: Who Should Check With a Doctor First

Cordyceps has generally been well tolerated in the human trials published so far, with no serious adverse effects reported. That said, cordyceps works through the same adenosine pathway involved in some heart medications, so people taking cardiac drugs, blood thinners, or immunosuppressants should talk to a healthcare provider before adding it. The same goes for anyone who is pregnant, breastfeeding, or managing a chronic health condition. None of the studies above followed participants for more than 12 weeks, so long-term safety data is limited.

Evidence Limits

• All three human trials reviewed here had small sample sizes (9 to 28 people).
• No trial lasted longer than 12 weeks.
• Results differ by population, dose, species, and which performance measure was tested.
• Findings on ingredients don’t necessarily apply to any specific commercial product unless that exact product was the one studied.

FAQ

Does cordyceps actually improve athletic performance?

The honest answer is “it depends.” Some trials in older adults and recreationally active people found measurable improvements in exercise thresholds or time to exhaustion after several weeks of use. Trials in already highly trained athletes have generally found smaller or no effects. No trial has shown a large, universal performance boost.

How long does it take for cordyceps to show an effect, if it does?

In the trials reviewed here, the clearest improvements in VO2max and ventilatory threshold appeared after three weeks or more of daily use, not after a single dose. One study did find a change in time-to-exhaustion after just one week.

Is Cordyceps militaris as good as Cordyceps sinensis for performance?

Both species have been used in published human performance trials, though earlier research relied more on Cordyceps sinensis (as the Cs-4 fermentation product), while newer trials favor cultivated Cordyceps militaris. No head-to-head human trial has directly compared the two species for athletic performance specifically.

Is cordyceps safe to take alongside heart medication?

Cordyceps affects the same adenosine pathway that some cardiac medications target, so this combination should be discussed with a healthcare provider before starting, rather than decided on your own.

Related Reading

For a full breakdown of cordyceps compounds, sourcing, and what to look for on a label, see the Cordyceps Research Guide. If your main interest is everyday energy rather than athletic performance specifically, the Mushrooms for Natural Energy guide covers that ground. And since sourcing affects how much cordycepin a product actually delivers, the Fruiting Body vs. Mycelium guide is worth reading before comparing products.

Research Disclosure: Studies referenced in this article are cited for educational purposes. Findings relate to ingredients as researched in academic literature — not to any specific commercial product. This article does not constitute medical advice.