What's in it
What's in GU Roctane Energy Gel?
GU Energy is one of the original endurance gels, an American brand that has been in jersey pockets since the 1990s. Roctane is the premium line above the standard GU Energy Gel: higher sodium, and many flavors add amino acids and caffeine.
Each Roctane sachet is 31 g and delivers 21 g of carbohydrate from maltodextrin and fructose. Here is the honest catch: GU lists the two carb sources but does not publish the split between them.
On the label
Straight from the published labels, checked June 2026. Verify on the current label, brands reformulate.
GU Energy Roctane Energy Gel
gel31 g sachet
A real dual-carb blend, but an undisclosed ratio
Maltodextrin plus fructose is a genuine multiple-transportable blend, not single-source, which is good. But because GU doesn't publish the glucose:fructose ratio, you can't check whether it lands near the bands research points to: about 2:1 at 60 to 90 g/h, shifting toward 1:0.8 above 90 (Hearris 2022). The blend is real, the balance is a question mark.
21 g per gel means a lot of sachets
At 21 g of carbs each, hitting 60 to 90 g/h means opening 3 to 4 Roctane gels every hour. That is a lot of wrappers, and a real cost over a long session. Worth doing the math before race day.
High sodium, sometimes caffeine and amino acids
Roctane runs 125 to 180 mg of sodium per gel depending on flavor, higher than most gels. If you sweat salty that is a feature; if you already dose electrolytes in a bottle you may be doubling up. Some flavors also add caffeine and amino acids, so check the specific one.
Make your own GU Energy
If you would rather know your ratio than trust an undisclosed one, build your own equivalent. A maltodextrin plus fructose blend around 2:1 gives you a verifiable multi-transport mix, and you set your own sodium instead of taking whatever the flavor carries. The calculator solves the grams for your target g/h, and you can dial the ratio toward 1:0.8 above 90 g/h.
Frequently asked
What is GU Roctane made of?
The carbohydrate comes from maltodextrin and fructose. Roctane also adds higher sodium (125 to 180 mg per gel) and, in many flavors, amino acids and caffeine. GU lists the carb sources but not the ratio between them.
What is GU's glucose:fructose ratio?
GU doesn't publish it. The gel is maltodextrin (a glucose-type carb) plus fructose, so it is a multi-transport blend, but the exact split isn't on the label, so you can't confirm where it sits relative to the research bands.
Roctane or regular GU?
Roctane is the premium line. Versus the standard GU Energy Gel it carries more sodium and, in many flavors, amino acids and caffeine. Both use a maltodextrin plus fructose base.
How many GU gels per hour?
At 21 g of carbs each, reaching 60 to 90 g/h means roughly 3 to 4 gels per hour. If your gut isn't used to that volume, build up gradually.
Figures checked June 2026 against each brand's published label; always verify on the current label, as manufacturers reformulate. This is an independent, informational breakdown. carbsperhour is not affiliated with, endorsed by, or sponsored by GU Energy or any brand named here, and nothing on this page is medical or nutritional advice. GU Energy and other product names are the trademarks of their respective owners.