Energy gels have gotten complicated with all the carbohydrate ratios and caffeine levels flying around. As someone who’s bonked spectacularly on rides where I didn’t fuel properly, I learned everything there is to know about what keeps your legs turning past hour two. Today, I will share it all with you.
That’s what makes gel selection endearing to us endurance-obsessed riders — finding the formula your stomach tolerates while your muscles demand.
What Gels Actually Do
But what is an energy gel? In essence, it’s concentrated carbohydrates in portable form. But it’s much more than that.
During hard efforts, your body burns through glycogen (stored carbohydrates) faster than it can access fat stores. When glycogen runs low, you bonk — legs stop working, brain fogs, everything becomes miserable. Gels deliver fast-absorbing carbs to delay or prevent this crash.
Frustrated by hitting a wall on my first century ride, I started using gels systematically. The difference was immediate — I finished strong instead of limping home.
When to Use Them
Probably should have led with this section, honestly — timing matters as much as brand choice.
For rides under 90 minutes at moderate intensity, you probably don’t need gels. Your body’s glycogen stores handle it.
For longer or harder efforts:
- Take one gel 15-30 minutes before intensity begins
- Then one every 30-45 minutes during the ride
- Chase each with water (not sports drink — too much sugar)
Start fueling before you feel depleted. Once you’re bonking, it’s too late — gels take 15-20 minutes to hit your system.
Ingredients That Matter
Maltodextrin: Fast-absorbing carbohydrate. The foundation of most gels.
Fructose: Absorbs through different pathway than maltodextrin. Combining both lets you absorb more total carbs per hour (up to 90g/hour versus 60g/hour with maltodextrin alone).
Electrolytes: Sodium, potassium, magnesium. Replace what you sweat out. Important for long hot rides.
Caffeine: Reduces perceived effort, increases alertness. Useful late in long events. Save caffeinated gels for when you need the boost — tolerance builds quickly.
What I Actually Use
- SIS GO Isotonic: No water needed, easy on stomach, mild flavor. My default choice.
- GU Energy: Thicker consistency, requires water. Wide flavor variety. Good performance.
- Maurten: Expensive but genuinely easier to digest for some people. Uses hydrogel technology.
- Honey Stinger: Natural ingredients if that matters to you. Tastes like honey (obviously).
I’m apparently in the camp that prioritizes stomach tolerance over theoretical carb optimization. A gel you can’t digest helps nothing.
Common Mistakes
- Trying new gels on race day: Test everything during training. Stomachs are unpredictable.
- Not drinking water: Most gels need water for proper digestion. Skip water, risk stomach distress.
- Overconsumption: More than 90g carbs/hour causes GI problems for most people.
- Starting too late: Waiting until you feel bad means you’re already behind.
Alternatives
Gels aren’t mandatory. Other options:
- Chews/gummies: Same nutrition, different format. Some prefer the chewing.
- Real food: Bananas, rice cakes, PB&J. Slower digestion but psychologically easier for some.
- Drink mixes: Carbs in your bottle. Convenient but limits plain water intake.
Making the Call
Try several brands during training. Your stomach will tell you what works. Some people tolerate everything; others can only use one brand without issues.
For events, bring more than you think you’ll need. Better to have unused gels than to run out mid-race.
