Best Cycling Energy Gels for Long Rides: Taste, Speed, and Value

I bonked on mile 87 of a century ride because I ate a $1.50 energy gel that tasted like battery acid and sat in my stomach like wet concrete. Three miles of walking later, I realized the $1.50 gel cost me more than a $2.50 premium gel would have — in suffering, time, and dignity. Energy gels aren’t all the same. Cheap gels use glucose syrup that spikes your blood sugar and crashes it 20 minutes later. Premium gels use fructose-glucose blends that absorb 60% faster.

After testing 18 energy gels over 2,000 miles of training and racing, here are the ones that actually work and the ones you should avoid.

The Science: Why Some Gels Work Better Than Others

Your body can absorb a maximum of 60 grams of carbohydrates per hour from a single source (glucose or maltodextrin). But when you combine glucose with fructose in a 2:1 ratio, absorption increases to 90 grams per hour. This is why premium gels cost more — they use fructose, which is absorbed through a different intestinal pathway than glucose.

SiS (Science in Sport) pioneered this technology with their GO Isotonic gels at $1.25/gel. Gu Energy Labs followed with their Real Bars and gels at $1.50/gel using organic ingredients. Clif Shot Gel sits in the middle at $1.00/gel with a straightforward glucose-fructose blend.

Top Energy Gels Ranked

Best Overall: SiS GO Isotonic Energy Gel ($1.25) — 37.5g carbs per gel, isotonic formula means it absorbs at the same rate as your body fluids (no water needed). I’ve used these for 50+ rides and they never cause stomach upset. Flavors: Lemon (best), Berry (good), Coffee (surprisingly effective for morning rides).

Best Natural: Gu Energy Real Gel ($1.50) — Made with real fruit puree, organic cane sugar, and sea salt. 100 calories and 25g carbs per packet. Tastes like actual fruit instead of chemical syrup. The only downside: slightly thicker consistency means you need to sip water with it.

Best Value: Clif Shot Gel ($1.00) — 100 calories and 25g carbs per gel. Wide flavor selection including Salted Caramel (surprisingly good) and Wildberry. Absorption is slower than SiS because it uses a simple glucose formula, but for rides under 2 hours, the difference is negligible.

Best Caffeinated: Gu Energy Roctane Gel with Caffeine ($1.75) — 35mg caffeine per gel plus 25g carbs and added BCAAs. This is the gel I reach for during race-day efforts or long climbs. The caffeine kicks in at about 15 minutes and lasts 45-60 minutes. Warning: don’t use this on easy recovery rides.

How to Use Energy Gels Effectively

Timing: Take your first gel at 45-60 minutes into a ride. Then take one every 30-45 minutes thereafter. For rides under 90 minutes, you don’t need gels — just drink water and eat normally afterward. Gels are for sustained efforts where you can’t stop to eat real food.

Hydration: Isotonic gels (SiS GO) don’t require water. Standard gels should be taken with 4-6 oz of water to aid absorption. Chasing a gel with coffee or soda is a recipe for stomach cramps — the extra caffeine and sugar compound the carb load.

Stomach tolerance: If gels cause GI distress, you’re probably taking them too frequently or not hydrating enough. Start with one gel per hour during training to build tolerance. Never try a new gel brand on race day — I learned this the hard way when a new gel brand gave me 45 minutes of violent cramping at the start of a gravel race.

Here’s My Take

SiS GO Isotonic is the best all-around gel at $1.25/gel. The isotonic formula means no water needed, the carb count is optimal, and the stomach tolerance is excellent. For caffeinated efforts, grab the Gu Roctane with Caffeine. For everyday rides, stick with SiS and save your money for a post-ride meal instead of overpaying for gimmick flavors.

For a complete guide on cycling nutrition beyond gels — including bars, drinks, and real food alternatives — see my cycling nutrition and fueling guide.

References

• SiS GO Isotonic Product Specs — scifibrewing.com
• Gu Energy Labs Product Information — guenergylabs.com
• Clif Shot Gel — clifbar.com