By Ethan BrooksUpdated November 2026
If you are looking for sis energy gels uk options that fit a UK training and racing routine, SiS (Science in Sport) is one of the most widely stocked choices, and it competes directly with Maurten and a range of own-brand gels. SiS suits runners who want a familiar, carb-focused gel with a broad flavour range and easy availability. Maurten, which uses a hydrogel-based formula, tends to suit athletes who have struggled with stomach issues on conventional gels and who are willing to test it thoroughly in training first.
This comparison is based on what manufacturers specify and what runners commonly report, not on lab testing. It covers carbohydrate content, formulation, taste range, caffeine options, stomach comfort, availability and how each gel fits into a race plan. For a wider view of the market, see Top 5 Energy Gels for Runners UK Worth Considering in 2026.
| Criterion | SiS Energy Gels (standard range) | Maurten Gel 100 / 160 |
|---|---|---|
| Core formulation | Maltodextrin-based gel with fructose blend in some variants | Hydrogel technology, carbohydrate-dense in a thinner format |
| Carbohydrate per gel | Typically around 22 g per standard sachet, per manufacturer listings | Gel 100 around 25 g; Gel 160 around 40 g, per manufacturer listings |
| Caffeine options | Caffeine variants available | Caffeine variant available in some markets |
| Flavour range | Broad, including fruit, cola and variety packs | Narrower, with a more neutral profile |
| Ease of use | Standard sachet, can be taken with water | Needs to be taken with water; some runners find the texture takes adjusting to |
| Stomach comfort | Generally well tolerated when practised; individual results vary | Often described by users as gentle on the stomach; individual results vary |
| Availability in UK | Widely stocked in running shops and online | Good availability, though less universal than SiS |
| Best suited to | Runners wanting variety and familiar sachets | Runners prioritising gut comfort at high intakes |
Carbohydrate Content and Delivery
Carbohydrate delivery is the main reason most runners reach for an energy gel. For efforts beyond about 60 to 90 minutes, current sports nutrition guidance generally points to roughly 30 to 60 g of carbohydrate per hour, with higher intakes sometimes used by well-practised athletes using mixed-carbohydrate sources. Check your own target against your race plan and any advice from a qualified sports dietitian.
Winner: Maurten, for concentrated carbohydrate per gel. Maurten’s larger format (particularly the 160 version) delivers more carbohydrate in a single serving, which means fewer gels to manage over a marathon. SiS is still effective, but you will generally need to take more sachets to hit the same hourly total.
Whichever you choose, count the carbohydrate per hour rather than per gel. A simple plan is to take one gel every 30 to 40 minutes after the first hour, and always with water so the gel dissolves and empties properly.
Formulation and Stomach Comfort
Gut comfort decides more races than almost anything else. The thicker, maltodextrin-heavy gels can cause problems for some runners, especially at faster paces where blood flow is redirected away from the gut. SiS uses carbohydrate blends that many runners tolerate well when they have trained with them, but individual responses vary widely.
Maurten’s hydrogel approach is designed to be less concentrated in the stomach, and many users report a gentler feeling at higher intakes. That said, it is not a guarantee, and some runners find it harder to take quickly.
Winner: Maurten, for runners with a history of gut problems. If you have never had issues, SiS is a perfectly reasonable choice. Either way, test your fuelling in training, ideally on a long run that matches race conditions.
Anyone with a medical condition affecting digestion, or who is unsure how to fuel safely, should speak to a GP or a registered sports dietitian before changing their nutrition plan.
Flavour Range and Palatability
Taste fatigue is real. By mile 18, a flavour you disliked in training can become impossible to face. SiS has the wider range, with fruit flavours, cola and variety packs, which makes it easier to find something you can stomach across a long day or a multi-stage event.
Winner: SiS, for flavour variety. Buying a variety pack lets you test several flavours on long runs and find one or two that work. Maurten’s more neutral profile suits some palates but gives fewer options for those who need a change.
Caffeine Options
Caffeine can improve perceived effort and performance in the later stages of an event for many people, but it can also cause jitters, sleep problems or stomach upset if you are not used to it. Only use caffeine on race day if you have practised with it in training, and keep within published guidance for your body weight.
SiS offers caffeinated variants that are straightforward to slot into a plan. Maurten has a caffeine option in some markets, but availability can vary. For more on caffeinated options, see SiS GO Energy + Caffeine Gel Review: Sis Energy Gels Caffeine Pros and Cons.
Winner: SiS, for caffeine choice and availability.
Ease of Use and Race-Day Practicality
Practicality matters when you are running at pace and need to take a gel without slowing down. Both options are sachets that need to be taken with water. SiS sachets are familiar and easy to tear open, and they are widely found at UK race expos and running shops. Maurten’s texture takes a little getting used to, and some runners prefer to practise carrying and opening it before race day.
Winner: SiS, for familiarity and easy sourcing.
Availability Across the UK
For most UK runners, convenience of buying matters. SiS is stocked widely across running retailers and online, including in multipacks that work well for training blocks. A practical guide to pack sizes is available in Sis Go Energy Electrolyte Gels 20 Pack: A Practical Guide (2026) and SiS Energy Gels 30 Pack: How to Choose, Use and Fuel Your Long Runs.
Winner: SiS, for availability. Maurten is also obtainable, but you may need to plan purchases more carefully, especially if you want a specific size or flavour.
Which Should You Choose?
- Choose SiS Energy Gels if you want a familiar product, a broad flavour range, easy availability and caffeine options.
- Choose SiS if you are on a budget and want a reliable option without premium features.
- Choose Maurten if you have had stomach problems with conventional gels and are willing to test it thoroughly.
- Choose Maurten if you want more carbohydrate in fewer, larger servings for long events.
- Choose SiS for variety if you like rotating flavours across a training block.
- Consider a variety pack first if you are undecided, and test a few flavours on long runs before committing to a larger order. See SiS Energy Gels Variety Pack Review: Pros and Cons for an overview.
Whatever you choose, practise your full race fuelling plan in training, including the timing and the water you will take with each gel. For guidance on timing, read When to Take Energy Gels: A Marathoner's Timing Guide.
FAQ
Are SiS energy gels easy to find in the UK?
Yes. SiS is widely stocked by UK running shops and online retailers, and it is a common sight at race expos. Stock levels for specific flavours can vary, so buying a variety pack or a multipack is often the simplest way to ensure you have enough for a training block.
Do I need to take water with an energy gel?
Yes, for both SiS and Maurten. Taking a gel with water helps it dissolve and empty from the stomach more efficiently. Manufacturers generally recommend a specific amount of water with each gel, so check the packaging and practise the same amount in training.
How many carbohydrates should I take per hour?
For efforts longer than about 60 to 90 minutes, many sports nutrition guidelines suggest around 30 to 60 g of carbohydrate per hour. Your individual target depends on your pace, body size and gut tolerance. A registered sports dietitian can help you set a safe plan.
Can I use SiS gels if I have a sensitive stomach?
Some runners with sensitive stomachs tolerate SiS well, while others prefer alternatives such as Maurten. Start with small amounts in training and increase gradually. If you have a digestive condition or ongoing stomach symptoms, speak to your GP or a registered dietitian before relying on any gel on race day.
When should I start using gels during training?
Begin practising gels on long runs of about 75 to 90 minutes, a few weeks before your race. This lets your gut adapt to the carbohydrate load and helps you find the timing and flavour that works. For a step-by-step approach, see When to Take Energy Gels During Half Marathon: A Step-by-Step Timing Guide.
Conclusion
For most UK runners, SiS Energy Gels are the practical default: widely available, easy to use, with a strong flavour range and caffeine options. Maurten is the better fit for athletes who need more concentrated carbohydrate or who have had gut problems with conventional gels. The best choice is the one you have tested on long runs that match your race conditions, so start practising now and build your plan around what your stomach tolerates.
About Ethan Brooks
Ethan Brooks is part of our editorial team and reviews and edits our marathon & half-marathon guides, checking product details against manufacturer specifications and owner feedback.
