Over the past 15 years I have studied the eating patterns of elite runners over the world. These athletes consistently practice five key habits that together define the optimal diet for all runners. The good news is that they’re easy to follow.

Habit 1: Eat everything.

Elite runners don’t avoid entire food groups such as grains or meat and fish, and neither should you. Runners who do impose such restrictions on themselves frequently develop avoidable problems such as iron-deficiency anemia and chronic fatigue.

Habit 2: Eat quality.

While they don’t forbid themselves anything, elite runners eat minimal amounts of the following four low-quality food types: refined grains, sweets, processed meats, and fried foods.

Habit 3: Eat carbs.

Carbohydrate has developed a bad reputation in the general population, but elite runners still eat them in abundance. They’re smart to do so: Science has consistently shown that when runners reduce their carb intake, their performance level drops.

Habit 4: Eat plenty.

Elite runners tend to focus on making sure they eat enough rather than on avoiding eating too much. Runners who eat even slightly too little often suffer consequences that include poor workout performance, slow recovery, and increased risk of injury and illness.

Habit 5: Eat individually.

Each runner is unique. Elite runners are good about paying attention to how their individual body responds to different eating patterns and adjusting their diet accordingly. Follow their example and develop your own version of the optimal running diet.