The SiS Beta Fuel + Nootropics gels have one of the highest carb contents around, with nootropics to boost mental alertness…

SiS Beta Fuel + Nootropics

£72 for 30 – not currently available in the US, 

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  • Big hit of carbs 
  • Fast acting 
  • Added nootropics  


  • Artificial taste 
  • Not easily stashable 
  • Full of preservatives 

Taste: 3.5/5
Energy: 4/5
Portability: 3.5/5

Almost as important as picking the right running shoe is choosing the best running gel. The Beta Fuel range from Science in Sport (SiS) is all about maximising the amount of carbs you can get into your body every hour. The gels follow the SiS Beta Fuel carb drink powders by adopting a 1:0.8 ratio of maltodextrin to fructose. This dual-fuel blend uses two different transit systems to help get more carbohydrate into the body.  

SiS Beta Fuel + Nootropics carb content

Each 60g gel delivers 40g carbohydrate. That’s up there with the highest carb content of energy gels like Maurten Gel 100 and Precision Fuel and Hydration. The SiS Beta Fuel gels also pack an added hit of nootropics – supplements that help boost your cognitive performance, focus and motivation.  

There’s also a 250mg dose of cognizin citicoline, a chemical that supports brain function; 200mg caffeine; 1g taurine; and 200mg theanine, an amino acid shown to increase subjective feelings of alertness. Does it work? It’s hard to say. I can’t say I noticed any perceptible benefits in my tests, even when I used them deep into six- to seven-hour ultra runs where I needed a mental lift. And certainly not more than a regular caffeine gel.   

I tested the lemon and lime flavour (there’s also an apple version). While it tastes OK, it’s all very artificial. It’s not necessarily worse than other artificially flavoured gels, but I can’t say I looked forward to eating them. The consistency is pretty standard, too, and definitely needed water to wash it down. 

The 60ml gels are bigger and a little harder to stash than some smaller gels, but you’re getting double the carbs per gel and so may well need to carry less.  

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