Should Cyclists Fuel During 1-hour Workouts?

By Jim Rutberg,

Lots of cyclists rely on shorter rides, often indoors, throughout the year. During the fall and winter, this reliance on shorter indoor workouts increases even further. This leads to questions about fuelling short rides. Do you need to consume calories during a 60- to 75-minute ride? Would it improve performance if you did?

Why cyclists consume carbohydrate during exercise

Carbohydrate calories from sports drinks, bars and chews improve performance during longer workouts and races by sparing muscle glycogen stores. The average athlete can store about 1600 calories of carbohydrate as muscle and liver glycogen. The longer you have some glycogen in reserve the harder you can go toward the end of an event or long training session.

Once muscle and liver glycogen are gone, carbohydrate delivery to working muscles becomes more limited. That means you’re more reliant on fat and – to a lesser extent – protein for fuel. Limited carbohydrate availability means limited capacity for high-intensity efforts because carbohydrate is your high-performance, high-speed fuel.

You don’t need to eat carbohydrate during one-hour cycling workouts

During shorter (60-75 minute) workouts – even hard interval sessions – you’re not going to burn through all your glycogen stores. This means you can complete a high-quality, high-intensity interval workout and finish before diminished carbohydrate availability negatively affects power output. This only holds true, however, when daily nutrition – both total energy intake and macronutrient composition – is adequate to replenish carbohydrate stores.

But why not eat during short rides anyway? Mainly, it’s because short workouts are often high-intensity sessions. Many athletes find it difficult to consume food or calorie-rich drink while working hard, or they feel nauseated or bloated when they do. In these cases, consuming calories can diminish training quality more than enhance it.

On the other hand, would consuming carbohydrate improve performance if you could consume it during short workouts? There is some evidence that an oral carbohydrate rinse can improve performance even if the calories don’t reach your gut (Hartley et al., 2022). The protocol is literally to swish a carbohydrate-rich fluid like a sports drink in your mouth and spit it out. But before you start spraying sports drink all over the floor of your garage, the benefit is small and probably not worth the hassle unless you’re competing in high-level e-sports races.

Hydration is still crucial for short workouts

Keep in mind, however, that it’s important not to take the recommendations above too far. While you may have enough energy on board for 60-75 minutes of moderate to high-intensity training, you still need to take in fluids to help manage core temperature. This is especially true for indoor cycling because reduced airflow leads to increased sweat rates. For shorter sessions you can rely mostly on plain water. For longer sessions consider a lower-calorie, electrolyte-rich drink for hydration.

And remember that for longer workouts, anything longer than 75 minutes, you should consume 20-30% of your hourly caloric expenditure via carbohydrate-rich sports drinks and foods. For most people this will still be within the traditional sports nutrition recommendations of 30-60 grams of carbohydrate per hour.

Pre-, During-, and Post-Workout Nutrition for Short Workouts

To successfully fuel training when you don’t plan on eating during rides, you’re relying on high-quality foods before and after shorter workouts to provide the energy for training and adaptation. Some of the most frequent questions we get are about adjusting nutrition for workouts at various times of day. The strategies below are recommendations for short (60-75 minute) morning, mid-afternoon, or evening cycling workouts.

 What to eat for a morning workout

Pre– 1 bottle of water right when you get up. The food you eat before training serves to increase blood glucose. Have a small (100-200 calorie) snack, mostly simple carbohydrate, and maybe a small cup of coffee/espresso if you find you need some caffeine to adequately focus.

During– 1 water bottle of water. If you struggle with energy due to the overnight fast, increase the pre-workout snack or experiment with a carbohydrate sports drink during your morning workout.

Recovery– At least 700ml of water and a high-quality breakfast that includes 20-40 grams of protein along with carbohydrate. If you’re running short on time, a recovery drink with a smaller, on-the-go breakfast is a good compromise.

Eating for a mid-day workout

• Pre- 1 water bottle’s worth of H₂O throughout the morning. Carbohydrate-rich snack of 100-200 calories about an hour before your ride.
• During- 1-2 bottles, one water and one low-calorie electrolyte drink
• Recovery- At least 700ml of water immediately after. Nutrient-dense lunch that includes 20-40 grams of protein along with carbohydrate. Don’t overdo it. Rather than eating a huge lunch, keep your portion sizes reasonable. Add an afternoon snack that includes protein to help spread protein intake across the whole day.

What to eat for an evening workout

• Pre- 700ml bottle of water in the hour before workout; many athletes become gradually more dehydrated as the day goes on. Include a 100-200 calorie snack about an hour before your workout.
• During- 1-2 water bottles, water and/or low-calorie electrolyte drink
• Recovery- Nutrient-dense dinner within 60 minutes of the end of your workout. Consume at least 700ml of water before or with dinner. If you plan on using a Train Low strategy to ride a moderate-intensity endurance ride in the morning with low carbohydrate availability, eat lightly after your evening workout and consume mostly protein and fat with only a little carbohydrate from vegetables.

A word on Glycogen Replenishment

Glycogen replenishment is important for post-workout recovery, training adaptations, and fuelling for your next training session. When training frequency is high, it can be hard to fully replenish glycogen stores between workouts. However, unless you’re training or competing twice a day, or training hard the morning after an evening workout, missing the “glycogen window” isn’t the end of the world. Consuming a meal that’s rich in carbohydrate and protein within an hour after a short workout is a good idea. But, you should be able to fully replenish your glycogen stores within 24 hours through post-workout nutrition and your normal diet.

Reference:

Hartley, C., Carr, A., Bowe, S.J. et al. Maltodextrin-Based Carbohydrate Oral Rinsing and Exercise Performance: Systematic Review and Meta-Analysis. Sports Med 52, 1833–1862 (2022). https://doi.org/10.1007/s40279-022-01658-3