For runners looking to maximize their performance, the evidence suggests that fasting is not beneficial. Research clearly indicates that runners who fuel themselves perform better than those who run fasted.
Understanding Fasted Running
Fasted running refers to exercising after a period of not eating, typically overnight or for several hours. The idea behind it is that the body will burn more fat as fuel. While this can be true, it doesn't necessarily translate to better running performance.
Performance Implications
| Factor | Fasted Running | Fueled Running |
|---|---|---|
| Performance | Decreased performance | Increased performance |
| Energy Levels | Lower energy | Higher energy |
| Fuel Source | Body relies more on fat (but not necessarily efficiently) | Body utilizes glycogen for high-intensity output |
Why Fueled Running is Better for Performance
- Glycogen Stores: Muscles primarily use glycogen (stored carbohydrates) for high-intensity activities like running. When you run fasted, your glycogen stores are depleted.
- Reduced Intensity: Without adequate glycogen, your body struggles to sustain high-intensity efforts, potentially leading to decreased speed and endurance.
- Fueling Strategies: Consuming carbohydrates before or during a run provides the body with readily available energy to optimize performance.
- Consider easily digestible carbohydrates 30-60 minutes before a run.
- For longer runs, consider a sports drink or gels for mid-run fuel.
Practical Insights for Runners
- Prioritize Carbohydrates: Fuel your runs with carbohydrates for optimal energy.
- Experiment with Timing: Find out the best pre-run fueling timing that works for you.
- Focus on Hydration: Stay well-hydrated both before and during your run.
- Listen to Your Body: Pay attention to how your body feels when running fueled versus fasted.
In summary, while fasted running might have a place for some individuals, it's generally not recommended for those seeking to enhance their running performance. According to research, running fueled is more likely to lead to optimal results.
