I’m not a doctor or a dietitian. I’m an enthusiast collecting what I’ve learned so far so you can pressure-test it, practice it, and hopefully dial in a strategy that works for your body and your goals. The headline is that in endurance sports, nutrition is not optional. It is a performance limiter or a performance enabler. Treat it like training and give it time. And above all, don’t do what I did, do NOT experiment with this on race day 🙂

Watt are the basics?

Start with the big three: carbohydrates, fluids, and electrolytes. For efforts longer than about 60–75 minutes, your onboard glycogen begins to matter, and what you take in during the session becomes decisive. Most people can absorb roughly 30–60 grams of carbohydrate per hour at first; with practice and a mix of glucose and fructose sources, many can push that to 60–90 grams per hour, and some well-trained athletes go higher (much higher nowadays, and this limit keeps getting pushed, super interesting field which I think contributes a lot to the better times and results that we keep seeing in races. If you are into these details, I recommend listening to the “Norwegian Method” podcast, or doing some research on that topic, those guys are data driven machines!).

Running tends to tolerate the lower to mid-range because of gut bounce in my very humbling of experiences.. cycling often allows the higher end because it’s friendlier on digestion. Labels are your friend, a typical gel is 20–30 g, a 500 ml bottle of carb mix might be 30–60 g depending on concentration. It is always very clearly labeled precisely so you can measure things out perfectly.

Fluids are another one that is very specific to each individual. It is in a way about matching enough of what you lose without chasing a perfect one-to-one replacement. The thing is, sweat rates vary wildly, from under 500 ml per hour in cool conditions to 1 liter or more in heat. Precision Hydration, the company (not sponsored, I promise), built its entire business model on this premise, so perhaps check them out for additional insight into the wonderful world of Sweat. They have a fun calculator you can use, I thought it was quite helpful.

Electrolytes, mainly sodium, help you keep drinking and keep the gut moving. I may do a separate write-up on what a lack of sodium may look and feel like, it helped me dial things in a bit better. But again, I am not a doctor! If you cramp, feel foggy, or stop wanting to drink in heat, look at sodium first, then overall carb intake, then pacing.

Watt I Learned

Food matters. Different people will enjoy different fuels. Some love gels, others solids only, others go all liquid. Whatever it is you pick, just don’t ignore food. It is literally your fuel.

In addition, timing matters. You will Hopefuly have heard this from other athletes and friends, but please eat before you get hungry, drink before you’re parched. On runs and rides beyond an hour, start fueling within the first 20–30 minutes and keep the drip going. Once you fall behind on carbs and fluids, you rarely claw your way back to feeling great. In marathons, a gel every 25–30 minutes with sips of water works for me personally. In triathlon, remember the bike is your nutrition buffet time. What you manage there largely determines how your run feels.

Above all though, really, race day is not for experiments. Bring what you trained with, or confirm the on-course options and practice with those exact products beforehand. If aid stations serve a drink mix you’ve never tried, treat it with caution and lean on your own supplies if possible.

I’ll end where I started: I am not a doctor or sports dietitian. This is a synthesis of common practices and what I’ve gathered by trial, error, and paying attention, and what was helpful for me. The main takeaway is simply that in endurance sports, nutrition is absolutely essential. Spend time on the details, practice your plan at the right intensity, and refine it. A disciplined fueling strategy has a massive impact.