Are Sweets Good While Running for Fuel?

November 14, 2025 •

4 min read

According to sports dietitians, all sports nutrition products, including gels and chews, are a form of sugar, and the strategic consumption of sweets can be a valid fueling strategy for endurance runners. This guide explores the science behind whether sweets are good while running, detailing the benefits and drawbacks for different types of workouts.

Quick Summary

This article explains how simple sugars from sweets can provide a quick energy boost during long or intense runs, helping to replenish muscle glycogen stores and delay fatigue. It also highlights the risks, such as sugar crashes and gastrointestinal issues, and advises on the best types of sweets, timing, and alternatives for effective performance fueling.

Key Points

Strategic Fueling: Sweets can be an effective, fast-acting energy source for runs lasting longer than 60-90 minutes, helping to replenish depleted glycogen stores.
Risk of Sugar Crash: Improper timing or excessive intake of simple sugars can cause a rapid energy spike followed by a crash, leading to fatigue and poor performance.
Best Sweets for Running: Jelly-based candies and gummies are often the best choice due to their high simple sugar content and low fat/fiber, which makes them easy to digest mid-run.
Poor Sweet Choices: Rich, high-fat sweets like chocolate bars are a bad idea during a run, as they slow digestion and can cause gastrointestinal discomfort.
Train Your Gut: It is crucial to experiment with fueling strategies during training, not on race day, to allow your digestive system to adapt to consuming fuel while active.
Pair with Electrolytes: Most sweets lack electrolytes; therefore, they should be consumed alongside water or an electrolyte drink to replace lost salts and prevent dehydration.
Not for Short Runs: Simple sugars are unnecessary for runs under 60 minutes, as your body's stored glycogen is typically sufficient.

The Science of Sugar and Running Performance

Carbohydrates are the body's primary and most accessible fuel source for exercise, breaking down into glucose to power muscles. For runners, managing carbohydrate intake is crucial, especially for longer, more intense workouts. While complex carbohydrates (found in whole grains and vegetables) provide sustained energy for daily nutrition, simple carbohydrates (sugars) offer a rapid source of fuel that can be highly beneficial during exercise.

During prolonged activity, such as a run lasting over an hour, the body depletes its stored energy (glycogen). To maintain intensity and delay fatigue, runners need to replenish these stores with easily digestible carbohydrates. This is where sweets, particularly those high in simple sugars like glucose, can be effective. They are absorbed quickly into the bloodstream, providing a fast energy boost to working muscles.

Strategic Sweet Consumption During a Run

For long or high-intensity efforts, consuming 30–60 grams of carbohydrates per hour is often recommended to sustain performance. For ultra-endurance events, some athletes may even benefit from up to 90 grams per hour by consuming a mix of glucose and fructose. However, it is vital to train your gut to tolerate this intake during practice runs to avoid gastrointestinal distress on race day. Here are some general guidelines:

For runs under 60 minutes: You likely do not need mid-run fuel, as your body's glycogen stores are sufficient.
For runs over 60 minutes: Incorporating 30–60g of simple carbohydrates per hour can be beneficial. Easily digestible sweets like jelly-based candies are an option, but be mindful of their ingredients.
For ultra-endurance events: Consuming up to 90g of carbs per hour may be possible, often by combining multiple sugar sources (like glucose and fructose) to maximize absorption.

The Dark Side: The Risk of the Sugar Crash

While beneficial when used correctly, improper fueling with sweets can lead to a 'sugar crash.' This occurs when a large dose of simple sugar causes a rapid spike in blood glucose, followed by an overproduction of insulin and a subsequent sharp drop in energy levels. Symptoms can include fatigue, dizziness, and irritability, significantly hindering performance. This is why simple sugars should be reserved for during and immediately after high-intensity exercise, not for a quick fix an hour before a run.

Not All Sweets Are Created Equal

When considering sweets for fuel, it is important to distinguish between those that are appropriate for exercise and those that can cause problems. The best options are typically jelly-based candies, which are high in simple sugars and low in fat and fiber, minimizing the risk of stomach upset. Rich, fatty sweets like chocolate bars or baked goods should be avoided mid-run as they slow digestion and can lead to gastrointestinal issues.


Feature	Jelly-Based Sweets (e.g., Gummy Bears)	High-Fat Sweets (e.g., Chocolate Bar)
Fuel Type	Primarily simple carbohydrates (sugars).	Mix of sugars and high fat.
Digestion Speed	Very fast; easily absorbed.	Slows down digestion significantly.
Energy Boost	Quick, immediate surge of energy.	Slower, more sustained release but prone to gut issues.
Gut Comfort	Less likely to cause issues during high-intensity exercise.	High risk of stomach cramps, bloating, and discomfort.
Electrolytes	Generally none, requires separate electrolyte intake.	Trace amounts, not a reliable source.
Nutrient Value	Minimal outside of carbohydrates.	Minimal nutritional benefit during exercise.

Proper Fuelling and Alternatives

For optimal fueling, consider these points:

Fueling before a run: A proper meal with complex carbohydrates should be consumed 2-3 hours before a run. For a shorter boost, a small, simple carb snack like a banana 30-60 minutes before is effective.
Hydration: Sweets do not contain electrolytes, which are crucial for performance. Pair your mid-run fuel with water or an electrolyte drink, especially during hot conditions.
Post-run recovery: Replenish glycogen stores and repair muscles within 30-60 minutes post-run by consuming a combination of carbohydrates and protein. A glass of chocolate milk or a fruit smoothie is a great option.
Natural sweet alternatives: Consider dried fruit like dates or raisins, which offer natural sugars and some micronutrients. Sports chews are another alternative, often fortified with electrolytes.

Conclusion: Mindful and Strategic Sweet Consumption

Ultimately, the question of "Are sweets good while running?" has a nuanced answer. Yes, simple sugar can serve as a highly effective, fast-acting fuel source during long or intense exercise when used strategically and in moderation. However, indiscriminate consumption or choosing the wrong type of sweet can lead to performance-sapping sugar crashes and digestive issues. For runners, the best approach is to practice with different fueling strategies during training runs to determine what works best for your body, saving simple, jelly-based sweets for when a quick energy boost is truly needed and always prioritizing hydration. For daily energy needs, focus on nutrient-dense, whole food sources of carbohydrates.

For more expert insights on athletic nutrition, visit the Precision Fuel & Hydration website.

Frequently Asked Questions

Yes, for many runners, regular jelly-based candies like gummy bears can function similarly to sports gels by providing quick-digesting carbohydrates during long runs. However, gels are often formulated with a specific blend of sugars and electrolytes for maximum absorption, whereas candy may lack electrolytes, so you will need to supplement them separately.

For exercise lasting 60–90 minutes or longer, a general recommendation is to consume 30–60 grams of carbohydrates per hour. For very long endurance events, some athletes might aim for up to 90 grams of carbs per hour by combining different sugar types like glucose and fructose.

Sweets can cause stomach problems, such as cramps or bloating, if they are high in fat or fiber, which slows down digestion. Eating too much sugar at once can also overwhelm your digestive system, causing discomfort. It is important to choose easily digestible options and test your fueling strategy during training.

The best time to consume simple sugars from sweets is during a long run or high-intensity workout, typically after the first 60 minutes, to provide a rapid energy boost. Avoid consuming a large amount of sugary treats in the hour immediately before a run to prevent a 'sugar crash'.

A 'sugar crash' (hypoglycemia) occurs when your blood sugar spikes from consuming too much simple sugar at once, prompting your body to release a large amount of insulin. This overcorrection causes a sharp drop in blood sugar, leading to fatigue, shakiness, and decreased endurance, which negatively impacts your running performance.

Yes, several healthier alternatives exist. Dried fruit like dates and raisins offer natural sugars and some micronutrients, while homemade energy balls or chews can be customized with whole-food ingredients. Bananas are another classic option, providing simple carbs and potassium.

No, for shorter runs (under 60 minutes), your body's existing glycogen stores are typically sufficient to fuel your workout. Consuming unnecessary simple sugars could potentially lead to a sugar crash without offering any performance benefits.