Sport, Peak O2®, Unflavored, 4.2 oz (120 g)

NutraBio Peak O2® delivers a clinically studied blend of adaptogenic mushrooms designed to improve VO₂ max, power output, and fatigue resistance. It’s stimulant-free, making it ideal for sustained endurance and high-intensity hybrid training sessions. Users often report better repeat-effort performance and smoother energy without crashes. This is a strong choice for athletes focused on aerobic capacity and long-term performance gains.

I’ve been using NutraBio Sport Peak O2® (Unflavored, 4.2 oz / 120 g) as part of my workout stack, and it’s quickly become one of my favorite performance enhancers. The packaging is clean and professional — a sturdy, resealable container that keeps the powder fresh and easy to scoop. The unflavored formula mixes effortlessly in water with no grit or odd aftertaste, which makes it super convenient whether I take it by itself or stack it with other supplements. Benefits I Noticed 🔹 Endurance & Stamina: Peak O2® helps me push through longer, harder workouts. I don’t fatigue as quickly, especially on sets that usually hit my breathing hard (like HIIT or 8–12 rep legs). 🔹 Better Oxygen Utilization: I feel like my muscles stay fresh longer and recover faster between sets — it really boosts how much work I can get in without relying on stimulants. 🔹 Pump & Performance: Not a traditional “pump” product, but I do feel more solid and in control during strength and hypertrophy work. 🔹 No Jitters or Crash: This is a big plus. It gives performance support without the nervous energy or the crash you get with some pre-workouts. 🔹 Clean Formula: NutraBio has solid quality control — no weird fillers, no artificial flavors, and transparent dosing, which I appreciate for long-term use. Packaging & Practical Use Size: 4.2 oz (120 g), which lasts a while with regular training Form: Unflavored powder — great for mixing into water or shakes Container: Easy-scoop jar that seals tight Usage: 20–30 minutes before training

My friends that play high endurance sports are in love with this product. They say that nothing improves their performance like PeakO2.

based on research I had opted to buy the product, however could not stay consistent enough to observe any benefit post using it for a month, it's doesn't have any immediate observable benefit. tastes like mud. if you can stay consistent over a long time may be beneficial.

It's a game changer. It allows me to swim faster for longer period of time. The difference is measurable. It doesn't lasts very long. But for me it covers about 1.5-2 hours after intake.

I continue to be impressed by NUTRABIO - the simple, clear, quality packaging offers ample confidence that the product inside will likewise be simple and effective.

Quality is great. Packaging is also good. Size is reasonable as well. Great list of minerals. Great supplement for daily usage with ample benefits. Composition is on point. Definitely a repeat buy for frequency. No taste, which is great. Ingredients are pure.

Thank you very much for this product, it suited me, I like the packaging, comfortable and stylish, I will order more of these products, and recommend them to all my friends and relatives! good!!

I’m satisfied with this product. With consistent use, Peak O2 provides a more stable level of energy and endurance, especially during longer or high-intensity workouts. The effect is not immediate — it builds up, but after 1–2 weeks the difference becomes clear. Breathing feels easier, fatigue sets in later, and recovery between sets is faster. The unflavored powder mixes easily with water or other supplements, which makes it convenient. For the price, it’s a solid choice for anyone looking to add a little extra stamina during training.

Very ckean and quality ingredients. Easy to add as daily supplement.