fastr 500 Bottle
fastr 500 Bottle
- Buffers Lactate
- Delays Fatigue
- Gut Friendly
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Try it risk free – 99-day money back guarantee
How Does It Work?
How Does It Work?
ZoneX is a powdered drink mix, formulated with a precise blend of ingredients that buffer lactic acid, letting you run harder and faster for longer than you would otherwise be able to.
Simply mix it with water, drink an hour before your race, and feel the magic unfold.
What's The Science?
What's The Science?
During high-intensity efforts, your body produces lactic acid as a byproduct of anaerobic metabolism.
This acid accumulates in your muscles - leading to that familiar "burning" sensation, muscular fatigue, and a drop in power output.
ZoneX combats this by buffering the production of lactic acid. The sodium bicarbonate in our blend neutralises excess lactate before it interferes with performance.
How Soon Will I See Results?
How Soon Will I See Results?
Immediately.
Unlike many fad "supplements", you don't need to be using ZoneX for months before you notice a difference.
Drink one sachet 60-90 minutes before your next session or race, and you'll feel the effects immediately.
You’ll feel the biggest difference during hard efforts (intervals, tempo runs, races, or anything that pushes you near your limit).
Who Is ZoneX For?
Who Is ZoneX For?
ZoneX is for runners, triathletes, and endurance athletes who want to compete at their true physiological ceiling.
But we don't want these gains to just be reserved for the elites. That's why we've designed and priced ZoneX in a way that makes it accessible to both everyday and professional athletes.
Whether your aim is to train more effectively, set new PB's, or beat your rivals - if you're serious about improving, ZoneX is for you.
Ingredients
Ingredients
Sodium Bicarbonate - 10,000mg: A powerful lactic-buffering agent that neutralizes lactic acid buildup in muscles — delaying fatigue and helping you push harder, for longer. Proven effective in dozens of endurance performance studies for over 40 years.
Sodium Citrate - 8,000mg: Works alongside sodium bicarb to support lactic buffering, while improving taste and reducing stomach distress.
Glucose - 10,000mg: Rapid-acting fuel that enhances muscle glycogen, providing the immediate ATP needed for strong finishes.
Citric Acid - 1,000mg: Naturally found in citrus fruits, citric acid aids digestion and pH regulation. It also helps improve solubility and flavour balance in the mix.
Natural Lime Flavouring & Sweeteners - Used in trace amounts to give ZoneX its zingy lime punch taste. No artificial dyes, no added calories — just a clean, punchy flavour that goes down easy.
Shipping
Shipping
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Risk Free Trial
Risk Free Trial
We're so confident in the quality of our bicarb blend that we offer a 99-day money back guarantee on all orders.
If you don't hit a PB (at any distance) within 99 days of trying your fastr products, just send us an email and we'll give you a full refund. No questions asked.
How Do I Use It?
How Do I Use It?
1. Shake one full sachet into 250–500ml of water. Shake or stir well until fully dissolved. This can be prepared the night before a race for ease of use.
2. Drink 60 to 90 minutes before your run. This gives your body time to absorb and activate the ZoneX blend.
3. Sip slowly - ZoneX is best consumed gradually over 10-15 minutes to reduce stomach discomfort.
4. Go to work - ZoneX is built for race day, hard sessions, or any time you're pushing the pace.
10,000+ PB's Smashed With ZoneX:
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"Crazy results"
"Wanted to see if I could get the bicarb benefits without the gloopy taste. WOW, yes; it works. Crazy results, both in training and races!"
- Charlie, 37
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"PB by 42 seconds"
"Took ZoneX before my 10K and felt so strong the whole way. No drop in power at halfway, and way less burn in the last 2k. Smashed my PB by 42 seconds."
- Richie, 28
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"Bicarb Works"
"Heart rate stayed lower at the same pace, and I held threshold 10 minutes longer than normal. Bicarb works. ZoneX just makes it tolerable."
- Harry, 20
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"Finished strong"
"Didn’t think a powder could actually make a difference. Turns out it does. Legs didn’t blow up like usual and I actually finished strong for once."
- Sarah, 32
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"Great taste"
"Had great taste and I was able to get it down no problem at all, unlike other bicarb products."
- Pete, 36
Here's What's Inside Every Sachet
Sodium Bicarbonate + Sodium Citrate
In a clinically proven dose.
These act like a sponge for lactic acid, soaking it up before it reaches your muscles. Not a token amount—this is the exact clinical dose studied to alter blood pH, buffer hydrogen ions, and eliminate the metabolic burn during all-out efforts.
Glucose
• 10,000mg •Rapid-acting fuel that bypasses complex digestion to restore muscle glycogen instantly, providing the immediate ATP needed for strong finishes.
Citric Acid
• 1,000mg •Crucial for turning nutrients into pure usable energy, as well as preventing the stomach distress commonly associated with bicarb.
Natural Lime
• Trace Amount •Used in trace amounts to give ZoneX its zingy lime punch taste. No artificial dyes, no added calories — just a clean, punchy flavour that goes down easy.
A NEW PB IN 4 STEPS:
1: Pour & Mix
Pour 1 sachet into 250–500ml of water and gently mix it.
2: Sip slowly
Sip gradually over 10–15 minutes. No rushing.
3: Wait for magic
Wait 60-90 mins, to let the buffer system get into your bloodstream.
4: Run fastr.
ZoneX helps you hold pace longer, delay the burn, and smash your PB.
FAQ's:
What is ZoneX?
ZoneX is a pre-run drink mix formulated with a high-performance blend of two types of lactic acid buffers - sodium bicarbonate and sodium citrate. These ingredients act like a sponge for the lactic acid buildup that otherwise causes your legs to burn and slow down, allowing you to hold pace longer and push harder.
Our unique blend comes without the gut issues or bad taste of traditional bicarb products.
What events is ZoneX suitable for?
ZoneX is ideal for high-intensity efforts where fatigue builds quickly — like 5Ks, 10Ks, track sessions, hill reps, tempo runs, and threshold workouts. It’s especially effective in events lasting 3 to 30 minutes, where lactic acid accumulation is a major limiter.
For longer events (half marathon or above), it can still help during fast starts, surges, or negative splits — but it shines brightest when you're redlining.
How does sodium bicarbonate help with performance?
Bicarb helps to slow the accumulation of hydrogen ions (acid) in your muscles, delaying fatigue and allowing you to perform at higher intensities for longer.
Bicarb has been clinically proven for decades to improve endurance at threshold-level intensities.
Will it really improve my running times?
Recent peer-reviewed studies have shown bicarb supplementation can increase performance by up to 17% in real-world race efforts. That could mean seconds or even minutes off your PB, depending on distance.
Does ZoneX contain any banned substances?
No. ZoneX is free from ingredients on the WADA (World Anti-Doping Agency) prohibited list.
Will it upset my stomach?
Unlike traditional bicarb gels or capsules, ZoneX uses a revolutionary blend of compounds that are designed to make it easy on the stomach. 97% of users experience no GI issues when taken as directed.
How do I use ZoneX?
Mix one sachet with 250–300ml of water and sip slowly over 10–15 minutes. Drink it around 60–90 minutes before your workout or race for optimal results.
Why do other bicarb products cause gut issues?
High doses of straight sodium bicarbonate can increase stomach acidity and cause gas, nausea, or diarrhoea. ZoneX is formulated to reduce that risk using balancing agents and a smoother delivery format.
What does 'buffer' mean?
Buffering means neutralising the acid that builds up in your muscles during hard efforts — helping you delay fatigue and push longer before hitting the wall.
Can I prepare ZoneX the day before a race/training?
Yes - you can mix a sachet of ZoneX into a drink bottle anytime up to 24 hours before consuming it. This makes it super simple and easy to prepare the night before, leaving one less thing to think about on race day!
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