The WattPlan Podcast · Episode 23 · 9 min
How much should you eat on a long ride?
Next episodes: Should you eat 100g of carbs an hour? · What should you eat before a sportive or race? · What should you eat after a ride?
Read the transcript
James. Hello, and welcome to the WattPlan Podcast. I'm James. When I'm not juggling family, the day job and building WattPlan, I'm reading sports science I should have put down hours ago, with the odd podium to show for it. This week, the long ride. How much should you actually eat when you're out for four or five hours, and how do you stop the bonk sixty miles from home? Lyra, our AI research voice, is here, and every study is linked in the show notes.
Lyra. Eat more the longer you're out, and start before you're hungry. On a steady hour or two you barely need anything. For two to three hours, aim for up to about sixty grams of carbohydrate an hour, and on long, hard rides, up to eighty or ninety. The bonk is mostly what happens when the eating starts too late.
James. Everyone describes the bonk the same way. Like someone's pulled the plug. What's actually going on?
Lyra. That's a good description of it. Your muscles and liver store carbohydrate as glycogen, enough for roughly ninety minutes to two hours of hard riding. Once that runs low, you lean on fat, and fat can't hold the same power. So the eating isn't really about the first two hours. It's about making sure there's still fuel for the last two.
James. Where do sixty and ninety come from, though? They sound like numbers someone made up for a gel packet.
Lyra. Fair suspicion. They come from a 2014 review in Sports Medicine by Asker Jeukendrup, which set out advice by how long you ride. The key fact behind it is that one type of carbohydrate can only be burned at up to about sixty grams an hour. For ultra-endurance, the review goes to about ninety, but only with a mix, glucose with fructose for instance, so more gets burned and less sits in your gut. [2]
James. So the mixed sugars on the label aren't just marketing.
Lyra. Not in this case. They're how you get past sixty without your stomach complaining. And that's half the answer for riders who feel sick at higher intakes. Eat on the easier stretches, lean on drinks and gels when it's hard, make it up when the pace drops, and keep the sugars mixed.
James. Okay, here's where I don't buy it. Every fuelling guide I read works in grams per kilo. Surely a sixty kilo climber doesn't need what a ninety kilo sprinter needs?
Lyra. I'd push back on that one. The review says carbohydrate on the bike doesn't depend on body weight, or on how trained you are. It depends on how long and how hard you ride, and it can come down when the riding is easy. Body weight matters before the ride. The article's breakfast guide is one to two grams per kilo, a few hours before you start.
James. So breakfast scales with me, but the gels scale with the ride. That's weirdly freeing.
Lyra. It is, and it means your level changes the ride, not the rule. If you're new to structured training, most of your long rides are steady, so sit low in the range and build the habit. Start eating twenty to thirty minutes in, then something every twenty to thirty minutes. A timer on your bike computer will do the remembering.
James. And if you train with power, I'm guessing the watts tell you where in the range you are.
Lyra. Pretty much. Steady endurance power, the lower end. Climbs, group rides, anything near threshold, the top, because harder riding burns carbohydrate faster.
James. Hang on, though. Half the club swears by fasted rides to teach the body to burn fat. Aren't we undoing that by eating from twenty minutes in?
Lyra. Our article's view is that the odd fasted ride may nudge fat burning up, but under-fuelling regularly costs you training quality, and the training is what makes you faster. So if you do them at all, keep them occasional, and don't let them become your normal long ride. For most riders, most of the time, fuelling well and training well wins.
James. So fasted is a side dish at best.
Lyra. At best. And on a long ride it's how you meet the bonk on purpose.
James. Real food or gels, then? Because I will defend the rice cake.
Lyra. Defend away. The review says the carbohydrate can come as a drink, a gel or solid food. Most riders use products for the hard sections and real food on the steady parts, rice cakes, bananas, a sandwich. Mixing them also saves you from being sick of one flavour five hours in.
James. Drinking, then. I never know if I'm overdoing it or underdoing it.
Lyra. The honest answer is that riders differ a lot. A 2017 review in Sports Medicine by Lindsay Baker looked at sweat testing, and found that how much you sweat, and how salty that sweat is, varies widely between people, and even from day to day in the same person. Heat, intensity, body size and how acclimatised you are all play a part. [3]
James. So there's no magic number.
Lyra. Not one for everyone. The article's starting point is five hundred to seven hundred and fifty millilitres an hour, more in the heat, and thirst is a fair guide. To find your own, the review's simplest and most accurate method is the bathroom scales. Weigh yourself before and after a ride, and allow for what you drank.
James. And the white tide marks on my summer jerseys?
Lyra. That's salt, and the review says salt losses vary a lot between riders too. Under two hours, water is usually fine. Longer than that, an electrolyte drink makes sense, and if your kit comes back crusty, you're probably one of the salty ones.
James. Does WattPlan plan any of the eating for you?
Lyra. For an event, it can. Route analysis, in Premium, sets your pacing from your FTP and drops a feed marker about every forty-five minutes, with sixty grams of carbs at each, which is up to about eighty an hour. And if your event is a sportive, the Coach is told the same, about eighty grams an hour, with a drink every fifteen minutes.
James. So if you race, eighty or ninety is the number?
Lyra. If you race, or your event is long and finishes hard, yes, eighty to ninety, and rehearsed. The article's plan builds up slowly, from about forty grams an hour, adding a little every couple of weeks on long training rides. Anything above that range is something to practise for weeks, never to try on race day. Our hundred grams episode covers why.
James. And if your stomach just won't have it? Some people struggle at half that.
Lyra. They do, and nothing's wrong with them. Gut tolerance varies widely, and some riders find forty grams an hour hard work. Build up slowly, use more than one kind of carbohydrate, and remember that some fuel is always better than none. Forty grams an hour that stays down beats ninety that comes back up.
James. Where does the evidence run out?
Lyra. Neither review is a trial of riders like you on a Sunday sportive. One pulls together earlier studies, and the other is mostly about how to measure sweat. Neither says how long gut training takes, or what to do if forty grams an hour already upsets you. Nobody has tested that properly yet.
James. Right, give me something for this weekend.
Lyra. Three things. On your next ride over two hours, start eating twenty to thirty minutes in and keep a steady rhythm. Write down everything you eat and drink, and divide by the hours, so you know your real number. And weigh yourself before and after, so you know roughly what you sweat on a day like that.
James. Eat early, count honestly, get on the scales. And nothing new on race day, however good the gel on the expo stand looks.
Lyra. The bonk is settled in the first hour, not the last. You eat early for the legs you want at the end.
Lyra. The full article and every study we mentioned are on the WattPlan blog, linked in the show notes. And if you've enjoyed this, follow the WattPlan Podcast wherever you're listening, so you don't miss the next one.
James. And if you want a plan built around the time you've actually got, get WattPlan on the App Store or Google Play. Thanks for listening.
Voices produced with ElevenLabs. James's voice is a clone of his own, Lyra is an AI voice, and James reviews every episode.
Eat 30 to 60 g of carbohydrate an hour on rides of 1 to 2.5 hours and up to 90 g an hour beyond that, mixing sugars above 60 g. Those are the 2016 joint position stand's figures, and in a 2026 trial of 15 riders, 100 g an hour held late power better than 60 g over 4 hours.
How many carbs per hour should you eat cycling?
The 2016 position stand of the Academy of Nutrition and Dietetics, Dietitians of Canada and the American College of Sports Medicine sets the bands, and Asker Jeukendrup's 2014 review explains the ceilings. A single sugar, glucose or maltodextrin, is burned at up to about 60 g an hour, so anything above that must mix glucose with fructose. Tim Podlogar and Gareth Wallis, in a 2022 review, put the better mix at about 1:0.8 glucose to fructose rather than the older 2:1. The advice does not change with body weight or training status, Jeukendrup adds, and an easy ride needs less.
| Ride | Carbs an hour | Source |
|---|---|---|
| Under 45 minutes | None needed | Position stand, 2016 |
| 45 to 75 minutes, ridden hard | Small amounts, even a mouth rinse | Position stand, 2016 |
| 1 to 2.5 hours | 30 to 60 g, one sugar is enough | Position stand, 2016 |
| Over 2.5 to 3 hours | 60 to 90 g, glucose and fructose mixed | Position stand 2016, Podlogar and Wallis 2022 |
| A hard 4 hour event, gut trained | About 100 g, mixed 1:0.8 | Mazza and colleagues, 2026 |
Is 50 g of carbs per hour enough?
For a ride of up to 2.5 hours, yes. It sits inside the 30 to 60 g band. For 3 hours or more it is below the 60 to 90 g band, and the 2026 Odense trial shows what the bottom of that band costs. Oscar Mazza and colleagues had 15 trained male cyclists and triathletes ride 240 minutes at 60% of their fresh 15-minute time trial power, then repeat the 15-minute test, once on 60 g an hour and once on 100 g at 1:0.8 glucose to fructose, double-blind. Test power fell 9.3% below fresh on 60 g and 6.4% on 100 g (P = 0.025), a 9 W difference (P = 0.028), while muscle glycogen finished at similar levels, 192 against 209 mmol per kg of dry muscle (P = 0.56).
So 50 g an hour suits a 2-hour club run and falls short on a 4-hour sportive. Our October post on the 100 g trials covers that study in detail.
What the trials found
| Source | Riders and doses | What it found |
|---|---|---|
| Jeukendrup, 2014 review | Review, by ride length | About 60 g an hour from one sugar for 2 to 3 hours, about 90 g from mixed sugars for ultra-endurance |
| Position stand, 2016 | Three professional bodies, by ride length | 30 to 60 g an hour for 1 to 2.5 hours, up to 90 g beyond 2.5 to 3 hours |
| Podlogar and Wallis, 2022 review | Review, 90 against 120 g an hour | 120 g raises how much of the drink is burned, saves no glycogen, no performance evidence, so 90 g stays the ceiling |
| Mazza and colleagues, 2026 | 15 trained men, double-blind crossover, 60 against 100 g an hour for 240 minutes | Final 15-minute test 9 W higher on 100 g, power down 6.4% against 9.3% |
| Martyn and colleagues, 2026 | 8 trained men, 10, 90, 120 and 150 g an hour for 3 hours | Total carbohydrate burned 2.6 g a minute on 120 and 150 g, 2.3 g on 90 g. Best time to exhaustion at 107 g an hour, 95% CI 92 to 122 g, and the 150 g ride lasted no longer than 90 or 120 g |
What should you eat before a long ride?
The position stand gives 1 to 4 g of carbohydrate per kg of body weight in the 1 to 4 hours before any ride over 60 minutes. For a 75 kg rider that is 75 to 300 g, and 2 g per kg three hours out, 150 g, is the middle of the range. The position stand also suggests 5 to 10 ml of fluid per kg before you set off, 375 to 750 ml for the same rider.
How do you train your gut to take more carbs?
Eat the rate you plan to race on, in training, for weeks. Jeukendrup cites a study by Cox and colleagues in which 28 days on a high-carbohydrate diet, 6.5 g per kg a day with 1.5 g per kg of that taken during training, raised how much ingested carbohydrate the riders burned compared with 5 g per kg a day, and concludes that the gut adapts. So ride every long training ride at the event rate for the four weeks before the event. Mix the sugars, because Podlogar and Wallis found a ratio near 1:0.8 kinder on the stomach than 2:1 above 60 g an hour.
How much should you drink on a long ride?
Sweat rates during exercise run from 0.3 to 2.4 litres an hour, the position stand says, and a plan that suits most riders lands at 0.4 to 0.8 litres an hour. The simplest check is a weigh-in before and after a ride, which Lindsay Baker's 2017 review of sweat testing calls the most accurate method, with the aim of finishing no more than 2% of body weight down.
Drinking more than you sweat is its own risk. The position stand names over-drinking, fluid beyond sweat and urine losses, as the primary cause of hyponatraemia, a drop in blood sodium below 135 mmol/L. Add sodium when the ride passes 2 hours, when you sweat heavily, above 1.2 litres an hour, or when your kit dries white. Sweat sodium averages about 50 mmol/L, roughly 1 g per litre, though Baker's review gives a whole-body range of about 10 to 70 mmol/L.
A sample plan for a 3-hour and a 5-hour ride
| 3-hour steady ride | 5-hour hilly sportive | |
|---|---|---|
| Carbs during | 60 g an hour, 180 g in all, one sugar is fine | 80 to 90 g an hour, 400 to 450 g in all, mixed sugars, about 100 g if the finish is hard and you have rehearsed it |
| Fluid during | 0.4 to 0.8 litres an hour, 1.2 to 2.4 litres | 0.4 to 0.8 litres an hour, 2 to 4 litres, with sodium |
Our recovery nutrition guide covers the hours after, the race day nutrition post adds the start-line details, and training for your first sportive puts the long rides in the calendar.
How WattPlan reminds you to eat
In WattPlan's workout player, in-ride reminders run on any workout of 60 minutes or more. A drink reminder comes every 15 minutes and a feed reminder every 45 minutes, asking for 60 g of carbohydrate and 500 ml of fluid, and nothing fires in the final 15 minutes. That works out at 80 g an hour, so a rider working up to 100 g adds a gel between prompts.
Route plan writes the same feed into the GPX file it exports, a waypoint at the end of the first pacing segment after each 45 minutes of predicted riding, marked 60 g of carbohydrate and 500 ml of fluid, so on a long climb the marker can come later than the 45 minutes. The pacing calculator and our event plan pages mark where to eat as a km point on the route, every 45 minutes of predicted riding time and never in the last 15 minutes. None of them changes the dose for the ride length or your weight. Our view at WattPlan is that 60 g an hour is the floor for any ride over 2.5 hours, 80 to 90 g the target for a long sportive, and 100 g a rate to rehearse for a hard 4-hour event rather than a default.
What to do this week
- Count what you ate on your last ride of 3 hours or more and divide by the hours.
- Set the rate for your next long ride from the table, 60 g an hour for 3 hours, 80 to 90 g for longer, mixed sugars above 60 g.
- Weigh yourself before and after one long ride and set your bottles so the next one finishes under 2% down.
- Eat 1 to 4 g per kg in the 1 to 4 hours before, and find the amount your stomach likes on a training ride.
- If your target event is 4 hours or more and finishes hard, rehearse 100 g an hour on the long rides in the four weeks before it.
What we don't know yet
The two 2026 trials had 15 and 8 men and no women, rode in a laboratory, and neither abstract reports stomach symptoms or who supplied the drinks. The Odense trial compared 100 g with 60 g and not with 80 or 90 g, so it does not show that 100 g beats the top of the standard band. The gut training evidence rests on one 28-day diet study, and sweat sodium varies so much between riders that the average says little about you.
Sources
- Nutrition and Athletic Performance, Medicine and Science in Sports and Exercise
- A step towards personalized sports nutrition: carbohydrate intake during exercise, Sports Medicine
- Sweating Rate and Sweat Sodium Concentration in Athletes: A Review of Methodology and Intra/Interindividual Variability, Sports Medicine
- New Horizons in Carbohydrate Research and Application for Endurance Athletes, Sports Medicine
- Carbohydrate Intake of 100 vs. 60 g·h-1 During Prolonged Cycling Improves Durability Without Altering Muscle Glycogen Utilization in Male Endurance Athletes, Medicine and Science in Sports and Exercise
- Effects of 10, 90, 120 and 150 g·h-1 CHO on Substrate Metabolism, Exogenous Oxidation and Exercise Capacity: Implications for CHO Personalization, Medicine and Science in Sports and Exercise