Swimming is a sport that provides a full body workout, taxing almost every muscle group in the body rather than just focusing on one muscle group. From the arms and shoulders to the back, and from the core, to the legs and feet, there's no escaping the burn of an intense swim session.

Professional swimmers are never scrawny, are they? They are well-built, well-oiled machines with low body fat and strong muscles. The swimmer’s body may well be the ideal physique, and in this post we discuss how you too can build muscle by swimming.

However, trying to build muscle by swimming alone is difficult. It's much better to make swimming a part of a wider program and mix it up with some weightlifting. A good diet and optimal supplementation are also important if you want to truly bring about a change.

Why is swimming good for building muscle?

With its low-impact nature, swimming is ideal for just about anyone. Regardless of age and condition, the benefits include improved recovery, a solid cardiovascular workout and of course muscle toning and growth.

Swimming is like a form of resistance training. It's similar to weight lifting but doesn't place the same stress on your joints. The low-impact nature of swimming means it's a more sustainable method of toning muscles without the potential negative side effects commonly incurred with the continual lifting of heavy weights.

With the full-body workout that swimming provides, many muscle groups can be worked. Swimming surpasses most other sports in this regard by providing an ideal stimulus for muscle growth right across the body. In particular, the shoulders, abs, back, legs and triceps get consistently worked while swimming.

By swimming on a regular basis and repeatedly exposing your body to that resistance created when moving through the water, you encourage your muscles to adapt to the stimulus and hence grow and develop.

Swimming strength training exercises

How to do each of the main stroke styles and which muscles they help.

Front Crawl

Also known as freestyle , this is a movement that requires the swimmer to extend the shoulder as you go through the water.

Here’s how:

  • Begin by floating in the water on your front. Stretch your body out.
  • With your legs still stretched and your toes pointed, start kicking your legs up and down in a fast, alternating fashion. To do this correctly, your ankles need to flippereqsue, and as floppy as possible.
  • At the start, your arms should also be stretched out in front of your head. With each moment, you’ll need to pull one arm under your body, all the way round to the thigh, and then bring it back out of the water, sweeping it over your head then back into the water. Then do the same with your other arm. This should be done in a continuous motion, each arm flowing the other.
  • As one arm is stretched out in front of you and one is at your thigh, turn your head 90° to the side to breathe in.

What muscles does swimming Front Crawl work?

Not only does this swimming movement work the upper body muscles, it’s also great for the torso, abdomen, back and your lower body. Just the crawling arm motion alone is a great way of toning up for the deltoid and shoulder muscles. Your core is engaged through the exercise, which will have great results for your oblique muscles. Further to this, the fluttering kick leg motion will benefit various parts of your lower half. Such as foot muscles, calves muscles and hip flexors.

Woman swimming. Photo by Arisa Chattasa @golfarisa on unsplashlink


If you get this one right, it can be both relaxing and a workout. Similar to front crawl, the backstroke exercise targets a large selection of muscles simultaneously.

Here's how :

  • In a similar fashion to front crawl, rotating your shoulders and hips will generate momentum. As you lift one arm forwards of the water, the other will go in the opposite direction under water. Keep your legs close together and instead of kicking from the kenes, kick from the hips.
  • When lying in the water, you’ll want your body to stay as flat as plank throughout. The smaller your body shape, the less resistance you will be faced with as you swim, and will make it much easier to go faster.
  • It might be tricky, but try to keep your hips to float on the water’s surface. In reality they will sink a little below the surface, but this will still make it easier to stay flat whilst moving.
  • Try to keep your head still and neck relaxed as you swim. If you hold your head up too far, you could strain your neck. The best way to think about it is that you should want your ears to be under the water and your eyes should be looking up and backwards.

What muscles does swimming backstroke work?

While it’s similar to front crawl as it simultaneously focuses on a wide range of muscles, backstroke does differ as you won’t need to use your neck muscles as much by twisting your head when breathing in. This swimming style works inner and outer abdominal muscles, and also aims for the hamstrings, lower body muscles and hip flexors.

Two women mid backstroke. Photo from Ryan Fleischer via Unsplashlink


A method that allows you both a long time, and a good time in the water. It involves swimming on your front, pushing your arms forward and then sweeping them back in a circular motion. While this is happening, your legs are tucked in towards the body before kicking out. It is sometimes called the ‘Froggy”

Here’s how:

When in the water, make sure both your head and whole body (including shoulders, hips and legs) are as horizontally aligned as possible.

  • You will however want your body to be slightly sloped to allow leg kicks to stay under the water. To get the best workout possible, keep your hips from dropping into the water, and your legs should stay behind you rather than below you. The majority of the push forward power will come from the leg kick.
  • Keep your neck and shoulders in as relaxed a position as possible and look downwards as you move . This will reduce strain on both your arms and neck respectively.

What muscles does swimming breaststroke work?

A stroke that is preferred by less active or older swimmers. The breaststroke can help work out the lower limbs, with the kick action in particular helping work the quadriceps, hamstrings and gluteal muscles. The sweeping arm movements and head movements help the pectoral muscles, deltoids, triceps and biceps.

Similar to breaststroke in that it puts emphasis on the lower body, the butterfly stroke is also a great option. It works abdominal, gluteal muscles and lower back as you move through the water and lift your body to breath. It also gives the arm and shoulder muscles a good workout.

Two swimmers mid breaststroke. Photo via Avatar of user CHUTTERSNAP @chuttersnap via Unsplash link

Why Swimming Alone Isn’t Enough To Build Muscle

You can build muscle by swimming, but depending on your goals, swimming may not be enough in and of itself. By coupling swimming and weightlifting, you will make more impressive gains.

Most cardiovascular forms of exercise tend to break the body down. Cycling and running are prime examples of exercises that don't necessarily build muscle. Properly trained cyclists and runners want to minimise excess muscle mass. The nature of their sport means they must also carry that extra mass - and that excess shoulder and back muscle is not something any cyclist or long-distance runner wants to carry around.

Swimming, however, is different. Swimmers require muscle. Weightlifting can help apply that additional stress for optimal growth. When weightlifting, you should work the same muscles that you work in the pool when swimming. This means you should try and refrain from working the biceps and chest too much.

The Nutritional Protocol For Muscle Growth

However, trying to build muscle by swimming alone is difficult. It's much better to make swimming a part of a wider program and mix it up with some weightlifting. A good diet and optimal supplementation are also important if you want to truly bring about a change.

Swimmers eat a lot. Those who train for several hours a day tend to work up a big appetite. You may not be at the same level, but if you want to build muscle by swimming, then you absolutely need to dial your diet in.

As you train in the pool and the gym, your muscles get broken down. But the growth occurs once the body repairs the affected muscles. They grow back bigger and stronger than before, hence the increase in strength.

To aid your body in repairing muscle after exercise, you'll want to ensure that you consume enough protein. The building blocks of proteins are called amino acids, and it's these that the body uses to repair those damaged muscles.

If you're an active swimmer, you'll want to consume at least 2g of protein for every kilogram of body weight, perhaps more if you train intensely. Protein is best taken in the form of a shake directly after exercise, as this is when your body most needs it.

Carbohydrate intake is also important, especially if you're swimming at high intensity. Muscle glycogen levels can become depleted after an intense session, and by taking carbohydrates on board you help replenish those supplies. Carbohydrate also provokes insulin excretion. And with insulin being anabolic in nature, it means that it promotes that muscle growth we’re after.

The Importance Of Recovery

If you want to build muscle by swimming, then the actual building takes place out of the pool. It's crucial that you let your body recover after a hard swim session. While exercising, the body breaks down muscle, and it's when resting that you enable the body to rebuild stronger than before.

By resting and ensuring your body has its nutritional needs met, you give it the means to rebuild and adapt.

You can still swim each day if you like, but just ensure that you interspace the intense days with sessions where you take it easy in the pool. Working your muscles further when they have not yet recovered from the previous stimulus is not a good idea. However, light exercise still results in increased blood flow and that helps your body excrete waste products, thus aiding your recovery.

If you do try to build muscle by swimming, then at Decathlon, we’re with you every step of the way. With a host of swimming accessories and aqua fitness gear, you’ll be sure to find what you need to bring about the required response..