Mushroom Blend
Stim-Free Daily
Efectiv Nutrition PeakO2 Mushroom Blend 120g - 120g / Unflavoured
Efectiv Nutrition

Efectiv Nutrition PeakO2 Mushroom Blend 120g

★★★★★
4.4 | 5 reviews |  60 Servings
£19.99 £0.33/serving
2g PeakO2 Dose 2g of patented PeakO2 blend per scoop - the dose used in the published mushroom research.
Six Mushrooms Six adaptogenic mushrooms grown in the US - Informed Sport certified.
60 Servings 60 daily servings per 120g tub - two months of stim-free adaptogen support.
Flavour Unflavoured
Standard delivery
Next day (£5.99)
17,600+ Reviews
14-Day Returns
Est. 2005
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Food supplements should not be used as a substitute for a varied and balanced diet and healthy lifestyle. If you are pregnant, breastfeeding, taking medication, or under medical supervision, consult your doctor before use. Do not exceed the recommended daily intake. Store out of reach of children.

Unflavoured

Efectiv PeakO2 120g, Six Mushrooms at 2g Per Serving

Efectiv PeakO2 Mushroom Blend is an unflavoured powder containing 2g of the patented PeakO2 blend per serving. PeakO2 combines six adaptogenic mushrooms grown in the United States: cordyceps militaris, reishi, king trumpet, shiitake, lion's mane and turkey tail. The 120g tub provides 60 servings.

The 2g daily dose matches the amount used in published research on PeakO2 across a 7 to 21 day consistent-use window. The formula is Informed Sport certified, stimulant-free and completely unflavoured, so it can be added to any drink without altering the taste.

Add one scoop to water, a pre-workout, a protein shake, smoothie or coffee. As an adaptogenic blend, the benefits build with consistent daily use rather than from a single acute dose. Take consistently for at least two to three weeks before assessing.

PeakO2 suits endurance athletes, CrossFit and higher-volume gym users who want a non-stimulant daily addition to their routine. It pairs naturally with XL Nutrition The Purge on training days, or with Efectiv Performance Daily for a stimulant-free stack. If you want a quick acute energy hit before a single session, a caffeinated pre-workout is more immediately noticeable.

Key Benefits

Boosts Oxygen Uptake

Clinically shown to improve oxygen consumption during exercise

Extends Endurance

Reduces lactate and increases time to fatigue

6 Adaptogens

Cordyceps, Reishi, Lions Mane, Shiitake and more

Informed Sport

Tested and certified for professional athletes

Frequently Asked Questions

How do I take PeakO2 powder?

Take one 2g scoop daily, mixed into water, a pre-workout, a protein shake, smoothie or coffee. PeakO2 is unflavoured so it does not alter the taste. Use consistently for at least two to three weeks before assessing, as the benefits of the blend build over time rather than from a single dose.

How is PeakO2 different from a caffeinated pre-workout?

A caffeinated pre-workout gives an acute single-dose energy hit before a session. PeakO2 is a stimulant-free adaptogenic blend whose effects build with consistent daily use. They serve different roles, which is why many users stack PeakO2 daily and add a caffeinated pre-workout on hard training days.

Can I mix PeakO2 into my pre-workout or coffee?

Yes. PeakO2 is unflavoured and contains no stimulants, so it mixes into any drink without altering the taste. The 2g scoop dissolves quickly in water, coffee, pre-workout, protein shakes or smoothies.