By kazimladimeji 
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Winter training has a habit of collecting accessories. A fan, a towel, a bottle, a screen, then a box of gels beside the turbo. But do you need energy gels for indoor cycling every time you clip in?
My starting point would be the session you have planned. An easy spin after a normal meal and a demanding indoor endurance ride deserve different preparation. Buy fuel to suit the work you actually do, rather than treating a gel as part of the compulsory kit.
This is a researched buying guide, not a personal taste test. Product specifications and the manufacturer’s indoor-training guidance were checked on 20 October 2026.
What a SiS GO Isotonic gel gives you
Science in Sport specifies 22g of carbohydrate in each 60ml GO Isotonic Energy Gel. The carbohydrate source is maltodextrin. The company says the formula can be consumed without additional water to dilute it; that does not remove your separate need to drink during training.
Check the SiS GO Isotonic blackcurrant 30-pack on Amazon UK. Check the flavour, pack quantity and expiry information before ordering.
Start with duration, effort and your last meal
SiS’s indoor-training guide says fuelling requirements depend on both intensity and duration. That is a more useful starting point than counting gels simply because the clock has reached an hour.
- A short, gentle spin: consider what you have already eaten before automatically opening a sachet.
- A hard interval workout: plan your food and drink beforehand, especially when squeezing training between work and dinner.
- A longer indoor ride: have an intentional fuelling plan and keep your chosen food or drink within reach.
Those are planning prompts, not a personalised nutrition prescription. If you follow a coach’s or sports dietitian’s plan, use that to decide quantities. A manufacturer’s general fuelling target does not mean every rider needs the same intake on every session.
Gels, food or a carbohydrate drink?
The appeal of a gel is convenience: a measured sachet takes little preparation. Indoors, however, you also have the luxury of a nearby table. A familiar snack or a suitable carbohydrate drink may fit your routine just as well.
I would compare the cost per serving and how much carbohydrate you actually want. A cheaper box is poor value if you dislike the flavour or leave most of it unused. Start with a smaller purchase if you have never tried the product, and practise your chosen fuelling approach during ordinary training.
GO Isotonic, Beta Fuel and Hydro are different purchases
The existing comparison below includes energy gels and electrolyte tablets. Read the product names carefully: a hydration tablet is not interchangeable with a carbohydrate gel. Check the label for carbohydrate, caffeine and other ingredients rather than assuming every SiS sachet does the same job.
For the wider range, see our SiS cycling gels comparison.
Make the setup easy to use
Put bottles and unopened fuel somewhere you can reach without twisting awkwardly. Keep a bin nearby for sticky wrappers and wipe up spills before they reach the bike. Check the practical side too: our turbo trainer sweat-protection guide covers guards, mats and the after-ride routine.
Would I buy a box for winter?
For someone regularly doing longer rides or following a structured fuelling plan, GO Isotonic gels are a convenient option to compare. For occasional easy spins, I would first look at meal timing and what is already in the kitchen. The useful purchase is the one that solves a recurring problem in your training.
Sources
SiS GO Isotonic product specifications; SiS indoor-training guide. The comparison table is reused from our published SiS guide; prices and availability can change.
Featured photograph: Dmitry Limonov / Pexels, under the Pexels licence. Illustrative indoor cycling photograph; it does not show a product test.