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PeakO2® (Adaptogenic Mushroom Blend)

Cordyceps militaris / Ganoderma lucidum / Pleurotus eryngii / Lentinula edodes / Trametes versicolor / Hericium erinaceus
Evidence Level
Strong
1 Clinical Trial
4 Documented Benefits
4/5 Evidence Score

PeakO2® (Compound Solutions) is a patented, USDA Certified Organic blend of six adaptogenic mushrooms grown on organic oats in the USA — headlined by Cordyceps militaris with Reishi, King Trumpet, Shiitake, Turkey Tail, and Lion's Mane. University clinical studies report improvements in VO2 max, peak power output (about 17.6% in 7 days), time to exhaustion (about +65 seconds in 21 days), and blood lactate clearance. Often described as 'creatine meets beta-alanine but 6 weeks faster,' PeakO2® is one of the more clinically validated mushroom blends for athletic performance.

Studied Dose 1-4 g/day ongoing; 4 g/day for performance benefits; 12 g/day acute (7-day) protocol.
Active Compound Blend of Cordyceps militaris, Reishi, King Trumpet, Shiitake, Turkey Tail, Lion's Mane; beta-glucans, ergothioneine, cordycepin.

Benefits

VO2 max improvement and oxygen utilization

PeakO2® supplementation (4 g/day for 21 days) produced a significant improvement in VO2 max of about 4 ml/kg/min, roughly an 8-9% increase in aerobic capacity. VO2 max is the single strongest predictor of cardiovascular fitness and endurance performance, making this a notable outcome for a non-pharmaceutical supplement.

Supported by Trial 1

Peak power output +17.6% in 7 days

Competitive athletes supplementing with 4 g/day PeakO2® for 7 days improved peak power output by 17.6% vs baseline, while the placebo group decreased 11.8%. This rapid power enhancement (within one week) compares favorably to creatine (3-4 weeks to peak) and beta-alanine (4-8 weeks), earning PeakO2® its '6 weeks faster' characterization.

Supported by Trial 1

Time to exhaustion and endurance extension

PeakO2® extended time to exhaustion by about 65 seconds over 21 days of supplementation — a meaningful improvement for athletes in events where pacing and endurance are critical. The blood lactate clearance improvement observed alongside VO2 max gains suggests multiple complementary mechanisms for endurance enhancement.

Supported by Trial 1

Immune support and adaptogenic stress resilience

The six mushrooms in PeakO2® — particularly Turkey Tail (beta-glucans, PSK, PSP), Reishi (triterpenes), and Lion's Mane (hericenones) — provide comprehensive immune modulation, NK cell activation, and adaptogenic stress resistance. These benefits extend PeakO2® beyond pure athletic performance into overall wellness, recovery, and immune resilience applications.

Supported by Trial 1

Mechanism of action

1

Oxygen uptake optimization and ATP efficiency

Cordyceps militaris bioactives (cordycepin, adenosine, beta-glucans) improve mitochondrial oxygen utilization efficiency — increasing the ATP yield per unit oxygen consumed. Combined with ergothioneine (a mitochondrial antioxidant that protects against exercise-induced oxidative damage) and beta-glucans (which support cardiovascular function), PeakO2® simultaneously improves the oxygen delivery system (VO2 max) and cellular energy conversion efficiency (ATP per O2).

Clinical trials

1
PeakO2® for Cardiorespiratory Performance — UNC Trial
PubMed

Two-arm clinical study at University of North Carolina Chapel Hill. Low-dose arm: 1-4 g/day × 28 days (40 subjects aged 18-50). Outcomes: VO2 max, time to exhaustion, blood lactate. (Hirsch et al. 2021, J Diet Suppl)

40 adults (low-dose arm).

Low-dose PeakO2® (28 days): VO2 max increased ~+4 ml/kg/min, time to exhaustion +65 sec, reduced blood lactate vs placebo. Industry-funded (Compound Solutions). Note: 40 subjects in low-dose arm; cardiorespiratory effects of magnitude reported are substantial — warrants independent replication.

Side effects and drug interactions

Common Potential side effects

Excellent safety profile — certified organic, grown in USA
Mild GI adjustment possible — start with 1–2g/day
Turkey Tail and Reishi components — rare mushroom allergy; discontinue if allergic reaction
Contains ergothioneine — synergistic with antioxidant supplements

Important Drug interactions

Immunosuppressants — mushroom beta-glucans may stimulate immune function; caution in transplant patients on immunosuppression
Anticoagulants — Reishi has mild antiplatelet activity; monitor if on blood thinners
No significant pharmacokinetic drug interactions at clinical doses

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Frequently asked questions about PeakO2® (Adaptogenic Mushroom Blend)

What is PeakO2?

PeakO2® (Compound Solutions) is a patented, USDA Certified Organic blend of six adaptogenic mushrooms grown on organic oats in the USA — headlined by Cordyceps militaris with Reishi, King Trumpet, Shiitake, Turkey Tail, and Lion's Mane.

What is PeakO2 used for?

PeakO2 is researched primarily for Athletic Performance, Energy, and Immune Support. PeakO2® supplementation (4 g/day for 21 days) produced a significant improvement in VO2 max of about 4 ml/kg/min, roughly an 8-9% increase in aerobic capacity.

What is the recommended dosage of PeakO2?

The clinically studied dose is 1-4 g/day ongoing; 4 g/day for performance benefits; 12 g/day acute (7-day) protocol. Always follow the product label and check with a healthcare provider for personal advice.

Is PeakO2 safe, and does it have side effects?

For most healthy adults, PeakO2 is well tolerated at studied doses. Reported effects can include: Excellent safety profile — certified organic, grown in USA Mild GI adjustment possible — start with 1–2g/day It may also interact with some medications. PeakO2 is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does PeakO2 interact with any medications?

Possible interactions include: Immunosuppressants — mushroom beta-glucans may stimulate immune function; caution in transplant patients on immunosuppression Anticoagulants — Reishi has mild antiplatelet activity; monitor if on blood thinners If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for PeakO2?

NutraSmarts rates the evidence for PeakO2 as Strong (4 out of 5). It is backed by 1 clinical trial and 1 cited reference summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(1 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Hirsch KR, Smith-Ryan AE, Roelofs EJ, Trexler ET, Mock MG. Cordyceps militaris Improves Tolerance to High-Intensity Exercise After Acute and Chronic Supplementation. J Diet Suppl. 2017;14(1):42-53..PubMedUsed to support: RCT of Cordyceps militaris (the lead mushroom in PeakO2) improving tolerance to high-intensity exercise.