Anti-Fatigue Caps: Support for Long, Demanding Efforts
When the session moves beyond two hours, fatigue is not only a fuel issue. Anti-Fatigue Caps combine potassium and magnesium aspartate with ornithine alpha-ketoglutarate (OKG) for athletes preparing for sustained training and racing.
How to use it
- Before: take 2–4 capsules before longer training or racing.
- During: take 1–2 capsules per hour for extended efforts, following the label guidance.
- Build it into the plan: use alongside—not instead of—carbohydrate, fluid and electrolyte intake.
Why these ingredients?
Ornithine is involved in the urea cycle, the route through which the body processes ammonia produced during demanding exercise. Potassium and magnesium are included as aspartates in a formula designed for the steady work of long-distance training.
What the research found
In a two-hour cycling study, participants taking ornithine reported lower post-exercise fatigue; female participants also showed a smaller late-test fall in pedalling speed. Read the study.
Best for
- Long rides, runs and brick sessions
- Ultra-distance events and all-day adventure efforts
- Heavy-volume blocks where training quality needs to hold up late in the session
Build the full plan
For long events, pair this with a rehearsed energy and hydration plan, and use electrolytes according to conditions and sweat loss.
Let customers speak for us
Absolutely love this gel! Great taste, easy to take during runs, and it gives me the energy I need without upsetting my stomach. I’ll definitely keep using it!
Wonderful product to promote good sleep and recovery.Also tastes great.
Great endurance drink. I like the consistency of Hammer if having 6 scoops in 1 bottle. I'll be using Hammer for my Ironman Barcelona race.
By far the best tasting recovery drink I’ve used in over 25 years. Lovely taste and consistency. It’s my go to protein drink now!
Hammer Nutrition Perpetuem was a key part of my fuelling strategy for the Leeds Ironman last weekend.
It gave me steady, reliable energy throughout the race and, most importantly, sat really well in my stomach.
No heavy feeling, I was able to keep fuelling consistently right throughout my cycling. A great product for long-distance — so glad this was recommended to me during my early training in preparation.
Extremely useful to use whilst cycling, removes the faff of opening gels whilst cycling and the solid bottle makes it easy to get in / out of jersey pockets.
Brilliant product - i use these in all my endurance events - some lasting up to 20 hours. These are great to ensure you get the required electrolytes without over hydrating.
I use this every day! Highly recommend!!
Great product! Very good quality supplement
Great service and the products are amazing, especially for endurance sports. I'm a big fan of the Endrolytes Electrolyte Caps. Their magnesium supplement and vitamin D are also very very good! I would highly recommend.
I’ve used Hammer products for around 6 years now & my favourite by a mile is the hammer Perpetuem, it’s fueled my last 100 mile ultra marathon not to mention multiple long distance triathlon's . It has 180calories per serving and it’s 34g of carbs & 5g of protein seems to work well . I’d strongly recommend for anyone who wants to take on ultra races as this fuel will support you when you need it most .
I started using Hammer Heed and Perpetuem 5 years ago and it's been such a game changer for my. Finding nutrition you can trust is so important for any athlete and I highly recommend Hammer Nutrition for any distance and any sport.
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 £20.
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 us via the bottom of our Home Page 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 via teh contact us at the bottom of our Home page.
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 via our contact us at the bottom of our Home page.
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.