Endurance swimmers need proper nutrition and a healthy diet to fuel their body for a prolonged period of time because they go long distances. A healthy diet for an endurance swimmer provides an adequate amount of calories, carbohydrates, protein and fat. Carbohydrate loading may benefit an endurance swimmer, but it can have side effects and may not work for everyone.
According to Lehigh University in Bethlehem, Pennsylvania, swimmers need 3,000 to 6,000 calories per day. The President’s Council on Physical Fitness and Sports, PCPFS, says calorie needs can change based on age, gender, size and the intensity of training. The best way for swimmers to determine if they are getting the correct number of calories a day is to monitor their weight. A calorie deficit can lead to unintentional weight loss, fatigue and poor performance, while overconsumption of calories can cause unwanted weight gain.
Carbohydrates, Protein and Fat
The proportion of dietary carbohydrates, protein and fat are important to optimize the energy level and overall health of an endurance swimmer. Carbohydrates should make up the majority of a swimmer's diet because it is the preferred source of energy for muscles. Lehigh University recommends 5 to 8 grams of carbohydrate per kilogram of body weight per day. Healthy carbohydrates come from fruits, vegetables and whole grains while unhealthy carbohydrates include sugary foods, desserts, pastries and candy.
Protein should be consumed at 1.2 to 1.7 g/kg per day and is important for building and repairing muscle tissues. Lean proteins such as skinless chicken breast, eggs, low-fat dairy products, lean ground beef, fish, soy products, beans, legumes and nuts are preferable for endurance swimmers.
Lehigh University says swimmers should consume 1g/kg of fat per day. Fat should come from heart-healthy, unsaturated sources such as olive oil, vegetable oil, nuts, fish and avocado. Saturated and trans-fats found in butter, lard, shortening, chicken skin, cream and partially hydrogenated oils should be avoided, because they contribute to heart disease.
Carbohydrate loading involves increasing the amount of carbohydrates consumed several days before an athletic event. According to the Mayo Clinic, carbohydrate loading can help athletes improve their energy and performance and is especially beneficial for endurance athletes such as swimmers and marathoners. The PCPFS says athletes who carbohydrate-load decrease their intake of dietary fat and increase their intake of carbohydrates to 10 to 12 g/kg per day. The Mayo Clinic warns that carbohydrate loading is not for everyone. Side effects of carbohydrate loading include weight gain, indigestion and changes in blood sugar, all of which can affect performance.
Swimmers who are negligent about proper hydration increase their risk for dehydration and serious medical problems. Lehigh University says swimmers should drink 16 oz. of fluid two hours before practice and 5 to 10 oz. of fluid every 15-20 minutes during practice. The most accurate way to rehydrate after practice is to weigh yourself pre- and post-workout and drink 24 oz. of fluid for every pound that is lost. Water is the best beverage for rehydration, but swimmers who swim continuously for more than an hour may benefit from sports beverages.
Endurance swimmers who eat a healthy diet can get their daily nutrient requirement from food without the need for vitamin or mineral supplements. Ergogenic supplements such as steroids, amphetamines, protein, amino acids, caffeine, ephedrine and creatine often claim to increase muscle mass and endurance, decrease fatigue and improve performance. Swimmers should be aware that many ergonegic supplements have not been proved to be effective or safe; some are also illegal and are banned from sports organizations. Supplements are not federally regulated, and should not be taken prior to consultation with a physician.