Eating for Swimmers

Proper diets help out in the water

Swimmers doing freestyle in lane
Corey Jenkins / Getty Images

Avoid fat; fat is ok, eat it up. Avoid carbohydrates; carbohydrates should be the major portion of your diet. Consume a lot of protein; eat balanced portions of proteins, fats, and carbohydrates. There is a lot of conflicting advice about eating for swimmers. What you do depends on whom you believe and what you're trying to achieve. The best diet -- how much fat, protein, and carbohydrate -- is up to you, your personal needs, and your physician. Before beginning a plan of eating for swimmers, consult a doctor to reduce the chance of medical complications.

Some Popular Diet Concepts

Here is a sampling of appropriate diets for swimmers:

My Plate (from the US Dept. of Agriculture)

This plan recommends a balanced intake from all five food groups: grains, vegetables, fruit, dairy, and protein. This is the eating guide I recommend. The My Plate website has interactive tools to help you learn more about the guidelines and figure out a swimming diet.

Vegetarian Diets

They vary from avoiding some meats to shunning all animal products. These diets are more challenging to make complete for an athlete but still achievable. They may be healthier than many other eating plans.

40-30-30 Plans, Such as The Zone Diet

These stress the concept that what and how you eat has a powerful effect on your physiology and health. These plans recommend changes in the composition of dietary fats, exercise, omega-3 fish oils, and proportions in three main elements of nutrition: 40% carbohydrates, 30% proteins, and 30% fats.

High Protein, Low Carbohydrate Diets

These plans, such as The Atkins Diet, focus on lowering the overall intake of carbohydrates. These plans don't seem to fit into the general realm of fitness for swimming or other pursuits and limit the most easily accessed source of energy. They aren't recommended by the American Dietetic Association due to the larger portions of fat and increased demand on kidney and liver function.

These and other plans have rules and guidelines regarding what and how much to eat. Swimmers, like other athletes, must take in enough calories to offset those used in exercise and non-workout times.

What Is a Calorie?

A calorie is a unit that tells you how much "energy" is in a type of food. Carbohydrates and protein have 4 calories per gram, while fat has 9. Some diets also consider the glycemic index of foods, or how fast a food increases the level of glucose in the blood.

How many calories do swimmers need a day? A rough rule is to multiply your weight in pounds by 12, but athletes need more. You could burn an extra 800 or more calories an hour during a workout.

Basic guidelines maintain that in a general diet, 60 percent of your daily calories should come from carbohydrates, 15 percent from protein, and 25 percent from fats. This will vary from plan to plan and from person to person.

Most experts advise swimmers to break up the standard three daily meals into smaller mini-meals throughout the day.

Guidelines for Eating

Here's how to eat before, during, and after swimming:


Eat three to four hours before swimming, primarily focusing on easy-to-digest carbohydrates with a low glycemic index, including fructose (a sugar with an index of 23 out of 100), apples, pears, yogurt, soybeans, kidney beans, skim milk, and peanuts.


Consume "sport" drinks that replace electrolytes and carbohydrates. Other easily digested foods may be consumed during prolonged periods of swimming or on long meet days. Look for low to moderate glycemic index foods, including moderate index foods such as lactose (a sugar with an index of 46 out of 100), popcorn, sweet potatoes, oranges, oatmeal cookies, orange juice, apple juice, grapes, and bananas.


Some studies suggest that you begin replenishing within 20 minutes of a swim. Rehydrate with water or sports drinks and replenish fuel stores with carbohydrates bearing a high to moderate glycemic index.

There's a growing movement to add protein and perhaps a bit of fat (4 parts carbohydrate to 1 part protein, and some incidental fat) to aid recovery. Also recommended are high index foods including glucose (glycemic index 100 out of 100), watermelon, pineapple, potatoes, waffles, bagels, bread, jelly beans, rice cakes, honey, soft drinks, and Rice Krispies.