How Does Swimming Change Your Body? (From body shape to fitness)


woman prepares to swim

As a regular swimmer, you might wonder if swimming changes your body shape and how quickly will you see results.

Typically, swimming regularly will change your body by toning your muscles, reducing fat, increasing your flexibility and improving your cardiovascular fitness. It is possible to see results in 6-8 weeks. However, this will differ between individuals and how often you swim.

As well as affecting how you physically look, regular swimming will also improve your cardiovascular and overall fitness levels.

But again, these are very general statements, so it’s good to know how swimming improves overall fitness and how long it takes to see results.

In this article I will cover:

  • How does swimming affect body shape?
  • How quickly does swimming change your body?
  • Does swimming lose belly fat?
  • What to do if you are not seeing physical results?

How Does Swimming Affect Body Shape?

Swimming is a wonderful exercise that is a full-body workout. This means that you are working every muscle in your body as you swim.

Depending on your swim stroke, you will work certain muscle groups more than others, but all swim strokes involve using the arms, legs, back and core body muscles.

As a result, you will see (or, more importantly, feel) changes to your body profile and shape over time if you are a regular swimmer.

Swimming is particularly good for improving our body shape in the following ways:

1. Swimming Reduces Fat

Swimming is a high-calorie burning exercise.

We burn an average of 250 calories per 30 minutes of swimming. [source]

Exactly how many calories you burn will depend on other factors, such as the level of intensity you are swimming and your current weight. However, all the experts agree that swimming is a high calorie-burning activity.

If you swim regularly, alongside a calorie-controlled or healthy diet, you will see significant changes to your body as you lose weight.

Swimming is such a high-calorie burning exercise. You will see and feel fat being lost from all over your body and that t-shirt or those tight jeans will feel just a little looser in 6 to 8 weeks.

2. Swimming Tones Abs

Swimming is a great resistive exercise for your muscles, especially your core muscles, which include your abs.

You should note that swimming does not build muscle, so if your aim is to “bulk up,” you are better off going to the gym and lifting weights.

Swimming will tone the muscles you already have and will do it with low injury risk, as it is a low-impact sport.

As so many swim strokes engage the core muscles, over weeks of regular swimming, you will at least feel that your abs have toned and will be shocked at the strength you can develop in your core.

Whether you actually see abdominal muscle definition will depend on the level of fat in your core region, and other genetic factors. However, you will feel a difference in strength.

As a regular swimmer, it shocked me how strong my core was when I took part in a fitness test that involved doing sit-ups until failure. (Which means, doing sit-ups until you can’t do any more)

I just kept going until it was time to stop. I ran out of time before my core muscles ran out of strength. I surprised myself!

I don’t have a noticeable set of abs to look at and I don’t build muscle definition easily, but I was pleasantly surprised at how strong my core muscles were just from regular and gentle swimming. I had good abs hidden away after all!

If your goal is to develop your abs, yet you are not physically seeing results, try to see how many sit-ups you can do. You will feel the results of your regular swimming on your core strength, even if you cannot see results.

If you are interested in targeting your abs specifically, check out this article that covers the road to getting abs from swimming in greater depth, Can Swimming Give You Abs? (The facts and road to success)

3. Swimming Tones Back Muscles

Swimmer bodies are famous for being toned, but an area in particular that is worked hard is your back muscles, especially if you are swimming the breaststroke or the butterfly.

The latissimus dorsi (back muscles), more commonly known as “lats”, are famously strong and toned in butterfly competitive swimmers. It is these muscles in the back that are one of the keys to achieving the coveted triangular upper body shape.

As a result, competitive swimmers have wide and very strong shoulders with a triangular frame.

Unless you are swimming at the level of a competitive swimmer, or find it easy to tone muscle and have broad shoulders already, you will not see a significant change in your shoulder body shape, but you will find that your back will become nicely toned.

As we do not always check our back out in the mirror, it’s easy to miss the excellent toning work that swimming does to our back muscles.

If you swim regularly, check out your back muscles in the mirror, as you might be pleasantly surprised!

4. Swimming Builds Strong & Toned Legs

We use the large leg muscles as part of every swimming stroke and as a result, swimming will build powerful leg muscles.

Swimming places the muscles under resistive load; as your legs kick in the water, they face the resistance that the water is placing on them.

In swimming, you will always face the same resistive weight (unless you use training aids such as pull paddles) and it will never be heavier than your own body weight.

As a result, you will not build or “bulk up” your leg muscles. In order to bulk up your muscles, you need to progressively increase the resistance your muscles are lifting over time.

With swimming, your legs muscles will become strong and toned with nice definition.

If you want to learn more about building muscles instead of toning them, check out this article which covers this in greater depth, Swim Or Gym: Which Is Better? (Explained)

5. Swimming Tones Arm Muscles

Although it is tricky to target arm muscles, swimming will tone your arms.

When you pull your arms through the water, the resistive load of the water will give your arms a great workout and you will start seeing and feeling tighter arm muscles.

How well your arm muscles show definition depends on many factors, including genes and hormones. However, your arms will be stronger.

If you want to give your arms a greater workout, you could use aqua dumbbells as part of your swimming routine or use swimming paddles, which will increase the resistive load placed on your arms.

If arms are an area in particular that you want to focus on, the following article covers this in detail, Will Swimming Tone My Arms? (Here’s what to expect)

6. Swimming Can Improve Posture

When it comes to body shape and using swimming as an exercise tool to improve our bodies, so many of us focus on the physical aspect of muscle toning and tightening that we can easily overlook that swimming can help with posture.

Do you spend most of your working week hunched over a desk? If so, start swimming a few lengths of backstroke as part of your workout.

The backstroke is a great swim stroke to improve posture as it involves stretching out on your back in the water, which elongates your spine and pulls your shoulders back.

Whether this has long term lasting effects is up for debate, but after a long day sitting at my desk, there is nothing better than a few lengths of backstroke to pull back my shoulders and stretch out my spine.

How Quickly Does Swimming Change Your Body?

Swimming is a great exercise to get your body into shape and you can see results in as little as 6 to 8 weeks.

At first, you may notice a tightening of your muscles or, if you have the body type, some definition in your muscles.

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As well as improving our physical appearance, swimming can cause important improvements to our heart health or cardiovascular fitness.

Swimming is a great aerobic exercise and swimming for 30 minutes, 3 times a week can improve our cardiovascular fitness in as little as 8-12 weeks. [source]

Does Swimming Lose Belly Fat?

For many of us regular swimmers, we are less concerned about building the perfect swimmer’s body and would be happy with just losing a couple of pounds around the belly.

It is not possible to target belly fat specifically, but as swimming is such a high calorie-burning exercise, if you combine high intensity swims with a calorie-controlled diet, you will certainly start to lose belly fat.

If you want to tackle belly fat through swimming, check out this article that gives advice on how to swim well for weight loss; Does Swimming Burn Belly Fat? (How to swim for weight loss)

What To Do If You Are Not Seeing Physical Results?

It can be very frustrating to swim regularly and not see any physical results or body shape improvements.

There are some common pitfalls that I have experienced that might hinder your progress.

Below are some ideas to work on if you feel you are not seeing fitness results from regular swimming.

1. Increase Your Swim Intensity

Swimming is such a lovely and relaxing exercise, it’s easy to take it slow in the pool.

In addition, if the pool is busy, it might force you to slow down in the lanes just to make room for others.

In order to improve your fitness in any sport, it is important to progressively challenge yourself. Therefore, the next time you are in the pool, try to increase your swim intensity.

You do not have to swim intensely for your full workout, just a couple of swim sprints with a 60-90 second rest at the wall between sprints will be good enough.

This increase in intensity will get your heart and lungs working hard and will help you burn more calories.

To learn more about how to do high-intensity training safely from a medical professional, check out the following book, Fast Exercise, from Dr Michael Mosley that shows the fitness benefits of increasing your exercise intensity.

You don’t have to be a sprint swimmer, you just need to increase your workout intensity within your own levels.

2. Try Not To Over Eat

With high calorie-burning exercises like swimming, there also comes an increase in appetite.

If you are swimming regularly, you might find that you are increasing your food intake to cope with the hunger that often follows a swim.

By increasing your calorie intake, you are negating all the work you did in the pool.

I have made this mistake in the past when I had a habit of loading up on carbs after a morning swim, only to find I was gaining weight and not losing it.

If you are not seeing results, look at your calorie intake, in particular any high sugar drinks you might take to supplement your training.

Final Thoughts

Swimming can have a profound effect on our body shape and fitness.

Although it takes a long time with intense training to develop the coveted “swimmer’s body,” you can feel amazing fitness benefits in as little as 6 weeks.

As well as the outward physical changes to our appearance, swimming can also have a fantastic impact on our cardiovascular fitness and mental health.

It is such a great full-body workout that will have a positive effect on your body regardless of your age, fitness level or swimming ability.

Happy swimming!

Louise Byrne

Hi, I am Louise and I am obsessed with swimming. I spend my free time in the water or getting ready for my next water adventure.

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