Race Day Boost is designed for athletes who want a real performance edge when it counts. Powered by sodium phosphate, its key active ingredient, some studies have suggested performance improvements of up to 8%.
With a simple four-day loading protocol, it supports all three energy systems, helping you perform more efficiently across steady efforts, high-intensity work and all-out sprints. By supporting oxygen use and helping buffer lactic acid, Race Day Boost is built to help you push harder, maintain pace for longer and turn up on race day ready to perform.
Race Day Boost is a key part of the Race PB Kit
WHAT RACE DAY BOOST DOES
- More time at anaerobic threshold (hold “hard” pace longer)
- Unsurpassed lactic-acid buffering (helps you resist the burn)
- Supports glycogen storage (more stored fuel)
- Gluten-free + vegan-friendly
- Better endurance
Race Day Boost is built around sodium (tribasic) phosphate, a performance ingredient that supports all three energy systems:
- Short efforts (ATP-CP)
- Hard sustained efforts (lactic/anaerobic)
- Longer endurance output (aerobic)
At the same time, it helps buffer acidity by neutralizing excess hydrogen ions—one of the main reasons high-intensity efforts feel like your legs are on fire. More buffering = more usable power before you fade.
The “8%” headline improvement in performance
In a large study on its primary ingredient, trained cyclists improved 40K time-trial performance by 8% after using a loading protocol.
INGREDIENT BREAKDOWN:
Sodium (Tribasic) Phosphate
- Supports ATP production across all energy pathways
- Helps buffer blood/muscle acidity
- Can increase 2,3-DPG, which helps deliver more oxygen to working muscles
Malic Acid
- Helps reduce the chance of stomach discomfort
-
Supports energy production (Krebs cycle support
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Supplement facts
- Serving size: 1 capsule
- Servings per container: 64
- Per capsule: Sodium phosphate 500 mg
- Other ingredients: vegetable capsule, magnesium stearate
HOW TO USE:
One-day “A” race
4 days before your event:
-
4 capsules, 4 times per day (with food + water)
= 16 capsules/day for 4 days
Multi-day events
3 days before the first stage:
- 4 capsules, 4 times per day
During the event (maintenance):
- After each stage: 4 capsules with Recoverite® ASAP
- Later that day/evening: another 4 capsules with food
Sodium note
Each 4-capsule dose adds about 440 mg sodium.
Standard loading = 4 doses/day, so that’s - 1,760 mg extra sodium per day during the load.
Translation: keep dietary salt lower during the loading phase—Race Day Boost is doing plenty of the sodium already.
FAQS
Is sodium phosphate in Race Day Boost and Perpetuem safe to consume?
Yes. Sodium tribasic phosphate (often called sodium phosphate) is considered very safe, especially in the small amounts used in Race Day Boost and Perpetuem. It has FDA “GRAS” (Generally Recognised As Safe) status and is widely used in foods and supplements as an emulsifier, nutrient, and stabiliser.
Toxicity levels are extremely high compared to normal use. For example, the LD50 (a measure of toxicity) for sodium tribasic phosphate in rats is 7,400 mg per kg of body weight. For a 75 kg person, that would equal around 555 grams—an unrealistically large amount that no one would consume.
For comparison:
- Sodium bicarbonate (baking soda): 4,220 mg/kg
- Acetic acid (vinegar component): 3,310 mg/kg
- Sodium chloride (table salt): 3,000 mg/kg
How much sodium is in a serving of Race Day Boost?
A four-capsule serving of Race Day Boost contains:
- 1,000 mg of trisodium phosphate
- 440 mg of sodium
The standard loading protocol is four servings per day for four days. This adds:
- 1,760 mg of sodium per day
- 7,040 mg of sodium over four days
Since most people already consume more sodium than needed, it’s important to reduce dietary salt intake when using this loading protocol.
Are your supplements third-party tested?
Yes. All Hammer Nutrition supplements are third-party tested to meet FDA regulations (21 CFR Part 111 – Dietary Supplements).
Every product is tested for purity, strength, identity, and quality. Testing takes place at every stage of production, including:
- Raw materials
- Blending
- Encapsulation or powder filling
- Packaging
- Finished products
Only after passing all checks are products released for sale.
What about sodium bicarbonate (baking soda) for performance?
Sodium bicarbonate has been shown to improve performance, but mainly in short, high-intensity exercise. It has not shown the same benefits for longer-duration efforts.
The main issue is the required dose. Effective intake is around 0.3–0.4 grams per kg of body weight. For a 75 kg athlete, that means 22.5–30 grams taken before exercise—a very large amount.
This often causes severe stomach problems. Research shows:
- 63–100% of users experience gastrointestinal distress
- Discomfort levels can reach 6 out of 10
In addition, sodium bicarbonate is 27% sodium. That means:
- 6.0–8.1 grams of sodium in a single dose
This is an extremely high sodium intake in a short time.
Why use sodium phosphate instead?
Hammer Nutrition considers sodium tribasic phosphate a better option because:
- It helps buffer acid and balance pH more effectively
- It supports all three energy systems in the body:
1. ATP-CP (short bursts)
2. Lactic acid system (medium effort)
3. Aerobic system (endurance)
Unlike sodium bicarbonate, which mainly benefits short efforts, sodium phosphate supports short-, medium-, and long-duration performance.
What does the research say?
Studies on sodium phosphate go back to the early 1990s. A key study by Dr Richard Kreider (1992) showed:
- 17% increase in power output
- 17% increase in oxygen uptake
- 8% improvement in time trial performance
The dosing used in Race Day Boost matches the amounts used in these studies.
Final point on safety
Sodium tribasic phosphate has an even lower toxicity risk than sodium bicarbonate. Both are extremely safe at normal usage levels, but sodium phosphate offers broader performance benefits with fewer side effects.
NUTRITIONAL INFORMATION
VIDEO:
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Frequently Asked Questions
How long will my delivery take and how much does it cost?
Orders placed before 2:00 PM (UK time) are dispatched the same working day. Standard delivery to mainland Great Britain takes 2–5 days at a flat rate of £3.50, or free on orders over £10.
Large tubs are automatically upgraded to DPD next-day delivery. Shipping to Northern Ireland, the Channel Islands, and the Scottish Highlands costs £4.50, or free on orders over £80.
Can I change or cancel my order after placing it?
Because we process and dispatch orders quickly, we are usually unable to modify products, delivery methods, or addresses after submission.
To cancel an order, you must contact us on the same calendar day it was placed. If dispatch has already occurred, you can return the unused items within 14 days at your own shipping expense.
What is your returns policy if I change my mind?
You have 14 days from the day after delivery to cancel your order. Items must be unused, in their original packaging, and in resaleable condition. Important Step:
You must email info@hammernutrition.co.uk first to obtain a Returns Authorisation Number and a free Royal Mail returns sticker; unauthorised returns cannot be processed.
Note that opened, sealed supplements cannot be returned for hygiene reasons.
What should I do if my order is damaged, faulty, or incorrect?
Check your parcel immediately upon arrival. If there is an issue, notify us within 48 hours of delivery at info@hammernutrition.co.uk.
Please include your order number, a description of the issue, and photos of the damaged items and packaging. We will provide a free replacement or full refund.
How long do refunds take to process?
Once your return is received, inspected, and approved, we process refunds back to your original payment method (card, PayPal, or bank transfer).
This typically takes place within 7 working days, and always within a maximum window of 30 days.
Are Hammer Nutrition products safe for drug-tested athletes?
Yes. Key products within our range—including Endurolytes (4ct/120ct), Endurolytes Extreme (3ct/120ct), Endurolytes Extreme Powder, and Endurolytes Fizz - are officially Informed Sport certified.
Additionally, our products are manufactured in strict ISO, GMP-compliant, and SQF Level 3 Certified facilities to ensure the highest standards of food safety and purity.
What do you use to flavour your sports nutrition products?
We use only premium ingredients with zero artificial flavours, artificial sweeteners, or chemical colorants.
Our natural flavours are extracted from real food sources (such as fruits, essential oils, and botanicals) in full compliance with FDA regulations.
They are entirely derived from non-allergenic materials and are formulated for a clean, subtle, non-sweet taste.
What should I do if my order has not arrived?
Estimated transit times are 2–5 days. If your parcel has not arrived within 5 days of placing your order, notify us immediately at info@hammernutrition.co.uk.
We will launch an investigation with the carrier and provide updates or arrange a replacement where appropriate.
Do you accept backorders for out-of-stock items?
No, we do not accept backorders. If an item is currently unavailable, you can enter your email address in the "email me when back in stock" widget directly on the product page to receive an automated real-time notification the moment inventory is replenished.
Are your supplements suitable for specific dietary restrictions?
Our clean sports nutrition range is formulated to support optimal body function and is completely free from gluten, artificial preservatives, and artificial colorants.
If you have specific medical conditions or severe allergen concerns, we recommend checking the explicit ingredient panels or consulting a healthcare professional prior to consumption.
