A: Gaining weight is a common runner phenomenon: You start increasing mileage for your next big race and the scale starts creeping up. The term for this is “train gain,” and it doesn’t just strike newbies. It can happen to anyone at any point in their running career.

A running program provides many health benefits. It increases cardiovascular efficiency by making your heart stronger and more effective. It increases your basal metabolic rate, helping you burn more calories when you’re at rest. And running itself burns calories. The amount of calories burned during a run is variable depending on the pace/intensity/duration of the run and size of the athlete, but in general, most runners can expect to burn between 80-100 calories per mile.  Yet all of this together does not inevitably lead to weight loss.  Here’s why:Runner

  1. Your weight is directly related to your diet. The foods you eat will either be burned in activity or they will be stored as fat for you to use later. There is no other option for those calories – they have to go somewhere. Generally speaking, people who are overweight are eating too many calories, but for runners especially, it can be too many calories from foods that are not useful to them for the activities they pursue in their daily lives.
  2. New runners and those increasing their mileage often have a greater appetite than before. When there is a change and the body is burning more calories, it is normal to be hungrier and craving more food. Again, this often means runners may eat more of the foods that they don’t need, which works against their desire to see weight loss (or at least maintenance) from increased exercise.
  3. New runners and those training for a longer distance than they ran previously often gain more muscle. Since muscle tissue weighs more than fat, some runners actually gain weight.

As a runner I often hear fellow athletes say “the reason I run is so that I can eat whatever I want!” As a dietitian I know it doesn’t work that way. Runners still need to choose foods wisely to avoid gaining weight. They may be burning more calories, but running (or any exercise) is not a license to eat whatever you want.

It’s important that you give your body the nutrients it needs, as opposed to just energy. As you run, you use up a lot of resources: minerals (like iron, potassium, sodium, and calcium), vitamins (especially B and C), as well as protein. In order to keep adding mileage efficiently, it’s important to replace all of those nutrients.  If you’re eating just to replace calories and not focusing on nutrients, your body stops being efficient. It slows down and it packs on weight.

It’s tempting to reach for foods with lots of fats and simple sugars (think cookies, cake, snack foods) to quickly replace calories lost to long runs, but those foods won’t replenish your nutrient stores in a way that allows you to maintain your training schedule. Because they are calorie-dense (and usually very tasty), it’s easy to eat more than you’ve burned.

Yes, there are some athletes who seem to eat a ton of food, yet they are what would be considered thin. This simply means that they are eating the foods they need to fuel their exercise and leaving out those foods they don’t.

Bottom line: While running burns calories, look carefully at what you’re eating.

  • Get enough carbohydrates, primarily from complex forms (like grains, rice, potatoes, pasta) for energy and lean protein including low-fat dairy for muscle growth and repair.
  • Choose foods high in minerals, especially potassium and calcium; good picks are milk, and yogurt as well as most fruits and vegetables.
  • Cut down on fats, oils and sweets that will keep you from losing/maintaining weight.

Aim to eat the right foods, in the right quantities, and you can manage your weight effectively.

For more information:

Eat Right for Endurance Sports.  http://www.eatright.org/resource/fitness/training-and-recovery/endurance-and-cardio/eat-right-for-endurance