The amount of calories burned while swimming depends on your weight, the speed of movement and what stroke is being used and is also influenced by one’s swimming skills. A skilled swimmer is more efficient and requires less energy, so they will need to swim a longer distance than an unskilled swimmer to achieve the same caloric expenditure. The caloric expenditure of simply treading water can be as high as 7.5 calories per kilogram of body weight per minute.

However, that last comment leads one to believe that it is better to be a poor swimmer if you want to burn more calories, but it backfires because you cannot swim very fast and get tired faster. The more skill you have as a swimmer, the less calories you burn per minute, but you actually burn more calories in the long run because you can swim faster and longer, So, in a nutshell, the less efficient swimmer cannot work out as long and inefficiency of skills can prevent the inexperienced swimmer from achieving a significant level of intensity.

So, take time to learn some of the more common swimming strokes. Each one burns a different amount of calories, and works each muscle just a bit differently. There are many sites that go in-depth about each technique’s arm and leg movements and breathing. Swapping around different strokes helps keep the body “guessing” so that it does not get used to a pattern and put you on that dreaded “plateau” if you are swimming for the purpose of weight loss.

In order of difficulty, the most popular swimming strokes are:

  • Treading Water and the Dog Paddle: Both of these are for someone who does not know how to swim, and are extremely inefficient and tiring even though the energy cost of simply treading water can be as high as 7.5 calories per kilogram of body weight per minute… Neither are recommended because it teaches bad habits.
  • Crawl (Freestyle): The most popular stroke that is the easiest for beginners to learn.
  • Backstroke: The backstroke is similar to the crawl in that you use an alternating windmill arm stroke and a flutter kick.
  • Breaststroke: The breaststroke involves exquisite timing, and if you are in a competition, you can be disqualified if you miss a single stroke.
  • Butterfly: This is a difficult stroke to learn and is not recommended for beginners due to the perfect timing requirement and the need for a lot of strength.

Swimming can give you even more of a caloric burn as well as a greater challenge to the upper body, if you try deep-water running in neck deep water. Also referred to as “water jogging”, this builds more upper and lower body muscular endurance than land-based running because the resistance of the water is surrounding you with every move.

Unfortunately, the charts and calculators around the internet vary widely in their calorie-burning data and the weights listed and it is unknown where most of them get their data. Calories burned come from a formula based on your metabolic rate, fitness level, speed, efficiency and weight, and there is no one-size-fits-all chart. Your weight may not be exactly what is shown in the charts, but if you fall between categories, you can at least get a general idea of calories burned.

Swimming for 1 hour 130 lb 155 lb 180 lb 205 lb
Laps, freestyle, fast 590 704 817 931
Laps, freestyle, slow 413 493 572 651
Backstroke 415 495 575 655
Breaststroke 590 704 817 931
Butterfly 649 774 899 1024
Leisurely, not laps 354 422 490 558
Sidestroke 472 563 654 745
Synchronized 472 563 654 745
Treading water, fast, vigorous 590 704 817 931
Treading water, moderate 236 281 327 372
Water aerobics, water calisthenics 236 281 327 372
Water polo 590 704 817 931
Water Volleyball 177 211 245 279
Water jogging, Deep-water Running 472 563 654 745
Diving, springboard or platform 177 211 245 279

By the way, because women have greater buoyancy due to naturally higher levels of body fat, they have an easier time staying afloat. This means that women expend fewer calories per mile than men, regardless of skill level.

Swimming is the “almost-perfect” exercise because it uses “almost” every major muscle in the body for toning, firming and strengthening. It burns a lot of calories, is joint-friendly, builds cardiovascular fitness and endurance, aids posture and keeps the joints flexible. There is little chance of injury and it is safe for babies and or the elderly. Cross-country skiing is actually the perfect exercise because it uses all muscles, but it can be dangerous for both babies and the elderly.

Swimming is a good choice for those who cannot take up weight bearing exercise, especially those with injuries, arthritis, chronic back problems, heart conditions, weight problems, or pregnancy who may be unable to participate in other types of exercise.

While no equipment is needed for swimming, other than a swimsuit (or shorts and t-shirt if allowed), wearing goggles to protect your eyes and earplugs to protect your ears from the water, whether it is a chlorinated pool, salt water or fresh water lake organisms, and a bathing cap to protect your hair and keep it out of the way are recommended. They all give you the freedom to maintain proper breathing techniques by keeping you from worrying about your eyes, ears or hair.

If you don’t know how to swim, or feel a bit rusty, you can find a Red Cross swim class in almost any community.

  • Swimming is referred to as an aerobic exercise because the utilization of oxygen by the muscles is tremendous, even if only doing a 3-minute lap. Cellular respiration is extremely important and is the process that muscles use to produce ATP energy. Oxygen is used to break down glucose and create the fuel for your muscles called ATP. And the more oxygen the muscles can utilize, the more ATP and the more calories are burned.
  • Doctors often prescribe swimming for those who have skeletal issues, injuries or heart problems because a person weighs only 10% of their body weight when in water, which is a nearly weightless situation. This means that we can work harder and longer with less strain on the muscles, joints and bones.
  • Exercising in water adds the element of resistance training and the body has to work overtime to supply enough oxygen into the blood, which makes swimming a good lung workout.
  • The cushioning of the muscles by the water’s buoyancy allows the heart to enlarge and pump between 10% and 20% more blood than usual with each beat. This provides more oxygen-rich blood to the muscles.
  • Swimming does not need to overwork the heart in order to improve lung function, or the body’s use of extra oxygen. Due to the compression on your body from the surrounding water, you will have to take shorter, quicker breaths. Research has shown that your lung capacity will be cut by up to 75% during and the body will try to compensate for it. If your swimming sessions last long enough, and you do it regularly, your respiratory system will become more efficient, and your lung capacity will increase.. This can help asthma suffers lessen their attacks over time.
  • In a horizontal position, there is no load on the spine and weight-bearing stress is eliminated.
  • Because of the resistance and compression that water provides, a half-hour of water exercise can produce the same results as two hours of land exercise with less effort.
  • Swimming is considered a low-impact to no-impact exercise for those with hip, knee, ankle or foot problems, because in water you are non-weight-bearing.
  • Some of the most important benefits of swimming are psychological. When you are under water, you tend to escape from the noise and distraction of life on land. The rhythmic strokes have a meditative quality that is calming, and there is just something soothing about being in water that helps take away stress. It’s almost like crawling back into the womb where there was nothing to worry about in the peaceful silence.
  • Swimming helps to build muscle coordination. If you have never done it, it will require you to pay attention to your breathing, your arm and leg movements as well as your body position, and everything should all move you in the same direction. Once you get the hang of it, it becomes second-nature. But it does not hurt to review your technique once in while to be sure you are efficient at burning calories.
  • Swimming can reshape the entire body. Try to swim at least 3-4 days a week for at least 1500m or a mile every time. If you switch it up with drills for kicking and different strokes as well as changing strokes to work different areas harder, you can potentially lose 10 lbs in a month.
  • It is recommended that you swim continuously for ten minutes, and then swim for twenty minutes at fast rate. If you want to get heart health benefits, swim at least 3 times a week. For a real challenge, increase the length of your non-stop lap swim sessions and you will soon be able swim 3 miles in 1.5 hours non-stop, and surprisingly, you will have burned a ton of calories, without feeling very tired at all.