Swim at least three times per week. You'll burn more fat if you swim more frequently, however, three times weekly is a solid start to your fat-burning plan.
Exercise at a slower pace for extended periods of time. You'll burn more fat if you slow your speed and swim for at least 30 minutes. When you exercise at lower intensities, you burn higher percentages of fat calories.
Increase your endurance. If swimming for longer than 30 minutes is difficult for you, gradually increase the time you spend in the pool. Begin by swimming consistently for 10 to 15 minutes. When you can complete that comfortably, add an additional five minutes onto your swimming time to burn more fat calories. Over the course of a few months, you should be able to increase your time in the pool, working up to the point where you can swim consistently for one hour.
Vary your swimming strokes. You'll get a better full body workout if you change your swimming stroke during your workout. Variation will also prevent boredom, helping you to swim for longer and burn more fat. Switch between backstroke, breaststroke, butterfly and freestyle every few laps.
Change your workout as you become stronger. After you have been swimming for a while, the same workout will no longer challenge you. At this point, you should increase the speed at which you swim your laps. Your body will then burn more fat since it has to rise to meet the new challenge.
Wear a heart rate monitor. Many heart rate monitors are waterproof and can be worn while swimming. Your heart rate monitor will help keep you honest, confirming that you are working to your potential. It can also help ensure that you are staying in the fat-burning zone while you swim.