VO2 max improvement and oxygen utilization
In a clinical study, PeakO2® supplementation (4g/day × 21 days) produced a significant 4 ml/kg/min improvement in VO2 max — a meaningful physiological increase representing approximately 8–9% improvement in aerobic capacity. VO2 max is the single strongest predictor of cardiovascular fitness and endurance performance, making this a landmark outcome for a non-pharmaceutical supplement.
Peak power output +17.6% in 7 days
A University of North Carolina, Chapel Hill study showed competitive athletes supplementing with 4g/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.
Time to exhaustion and endurance extension
PeakO2® extended time to exhaustion by 65 seconds over 21 days of supplementation in clinical studies — a meaningful improvement for athletes competing 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.
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.
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).
Two-arm clinical study at University of North Carolina Chapel Hill. Low-dose arm: 1–4g/day × 28 days (40 subjects aged 19–34). High-dose arm: 12g/day × 7 days (43 subjects). Published in Journal of Dietary Supplements.
83 subjects across two arms, ages 19–34. Competitive athletes.
Low-dose (28 days): Significant increases in VO2 max (+4 ml/kg/min), time to exhaustion (+65 sec), reduced blood lactate vs. placebo. High-dose (7 days): 17.6% greater peak power vs. placebo group (-11.8%). VO2 peak significantly improved in subjects below median baseline fitness. Overall: PeakO2® is one of the most clinically validated mushroom blends for athletic performance.