How Unhealthy Food Affects Running Performance | Livestrong.com (2024)

Unhealthy foods can have a negative impact on your running performance.

Image Credit: bhofack2/iStock/Getty Images

See Also

The Very Best Beverages for RunnersHealthy Meals, Snacks for RunnersWhat not to eat when you're training for a marathon | HealthPartners BlogShould You Eat Carbs Before Running?

If you want to improve your running performance, you need to train to improve your fitness and stamina and gradually increase your mileage. However, the factor which many people overlook when training for running is nutrition. Surprisingly, the foods you eat can have a huge effect on your running performance, and eating an unhealthy diet can cause your progress to decrease drastically.

Energy Levels

When you consume food, your body breaks it down either to be used as immediate energy or to be stored for later. High-calorie, nutrient-dense, healthy foods help to fuel running performance by making you feel more alert and energetic. However, unhealthy foods can lead to a decrease in performance. High-sugar junk food won't provide you with lasting energy, which will mean that you may suffer energy crashes and quickly feel fatigued after eating them. They can also make you feel bloated and uncomfortable.

Body Composition

Unhealthy foods contain huge amounts of calories, and once you start eating them, it is often difficult to stop yourself from overeating. This will lead to an increase in body weight and fat mass. Elite male runners often have a body fat of under 12 percent, and females 8 to 15 percent. While you may carry slightly more fat mass than that, the more you have, the more you will weigh, meaning that you will find running harder work and may struggle to maintain your speeds.

Blood Flow

When you run, your heart and lungs have to work harder than usual and require more oxygen. To do this, the rate and volume of blood pumped to these areas must increase. Many unhealthy foods contain large amounts of trans and hydrogenated fats. When consumed in excess, these can cause a build up of plaque in your blood vessels, meaning that the amount of blood which can get to your respiratory organs is decreased and you find running much tougher.

Healthy Foods

For the food you eat to have a positive effect on your running performance, you should base your diet around nutrient dense whole foods. Fuel your body with quality carbohydrates such as fruits, vegetables, sweet potatoes and brown rice. Consume protein in the form of meat, fish and dairy to repair muscle damage, and include healthy fats such as olive oil, nuts and coconut to aid in hormone production.