It’s the shortest part both in time and distance, but the triathlon swim is the most feared part of any triathlon and puts more people off taking part than any other part of the race!

Most of us learned to swim as kids, but have had little chance to practice these skills except for the occasional swim on holiday, so our technique and experience is limited. But for a triathlon, it’s worth starting from scratch and seeking a club or swim coach to get the basics right and build up confidence and endurance in a structured fashion, but if you want to go it alone, it’s worth understanding the basics of stroke and stroke mechanics before you get into the water and find a good training programme online.

The Swimming stroke.

Having the right technique is half the battle in the triathlon swim, so which one is best for triathlon and what are the key elements?

Although there are several to choose from, Freestyle tends to be the triathlon swimming stroke of choice.

If you watch triathlons regularly or happen to see a triathlon team training, you’ll notice that the fastest and most effective swimmers seem almost lazy in their stroke. Their heads are very low, the kick is rapid and shallow, their arms puncture the water rather than a splash and their arms are bent and stay close to their bodies.

They are also invariably doing freestyle rather than other Triathlon swimming stroke, which is faster and more efficient.

The reason for this is that efficiency is king and any energy that’s not adding to overall performance has to be conserved, making the freestyle the best triathlon swimming stroke. The high elbow stroke is more efficient as it transfers the most power backwards rather than downwards. The kick adds little propulsive power but keeps the body streamlined, and the low head minimises drag that can act as a brake as you breathe.

You aren’t restricted to freestyle and all are permitted in most races, but there are pros and cons to all.




animation of the freestyle swimming stroke

Freestyle is the most commonly used triathlon swimming stroke but, if you have a difficulty with this or a preference for another stroke that’s fine and all strokes are allowed in races with the possible exception of backstroke depending on the organisers

In freestyle or crawl, the body is face down, with the head maintained in the water s much as possible. The arms come over the shoulders out of the water and reach forward before being pushed back under the body to provider propulsion. Once the arms reach down to the hips they are recovered out of the water to complete the stroke. The legs tend to kick from the hips with pointed toes like flippers,

Breathing is accomplished by tilting the head to one side to inhale and spent air is exhaled into the water.

Freestyle has a number of advantages. firstly, it adopts the most streamlined position in the water with the head pointing down and forward. It’s also the fastest technique by a considerable margin.


breaststroke gif

The second most common stroke is breaststroke, which has a couple of advantages especially for open water and is a common recovery stroke for triathletes. Like freestyle, you are looking forward during the stroke, which naturally pushes your head out of the water which aids breathing and sighting, which keeps you swimming in the right direction. This also helps psychologically because you have visibility around you which can reduce any panic caused by having your head underwater.

The stroke is more balanced than freestyle and uses more of the leg muscles, which, although not ideal in terms of the subsequent events, can definitely help off your shoulders are tiring during the swim.

It is, however, the most energy-intensive stroke and definitely the slowest.


breaststroke gif


Backstroke isn’t quite freestyle in reverse as it uses the legs more for propulsion than the arms, simply because it is more difficult to engage the arms efficiently when pulling behind you. It’s definitely faster than breaststroke, but there’s not a lot in it! It’s also much easier to breathe what breaststroke because your face is out of the water but still in a streamlined position.

The biggest issue with breaststroke, however, is visibility. You have no real sense of what’s in front of you, so sighting can be a real issue and there is a good chance of crashing into other competitors, bollards or support boats! For this reason, some races will not allow competitors to do the backstroke, and it is generally reserved for recovery or if a swimmer is in distress.



Butterfly stroke animation

You’ll often see swimmers utilising the Butterfly kick at the start of beach swims to get through shallow water, but apart from that isn’t common. In theory, though it has a lot going for it as it utilises core muscle strength in for propulsion as well as legs and Arms, making it potentially more powerful and more balanced.

However, few people are taught to butterfly properly and bad technique significantly reduces the potential power benefits of the stroke. It’s also wider than freestyle increasing the chances of collisions with other swimmer disrupting your stroke. The breathing window is also short and missing breaths will slow you down.

The Freestyle Stroke

Swimming is a complex collection of movements and getting the right technique will provide significantly greater performance gains than focussing strength or endurance, so it’s definitely worth investing in a coach or learning more about the technicalities and jargon of swimming (Swimsmooth is very good for this). But it’s worth knowing some of the key features of the freestyle stroke before you start.

Top down Freestyle Stroke


The standard position for the freestyle stroke is face down in the water, with the head as low as possible. Propulsion mostly comes from the arm being pulled backwards in the water and then being recovered as it reaches the hips then moved forward out of the water to recommence the stroke. The arms move asymmetrically, so as one arm moves backwards, the other is being brought forward.

This side to side motion of the freestyle stroke, coupled with a need to lift the head out of the water to one side to breath leads to a corkscrew motion with the upper body rocking from side to side in the water, preferably from the hips.

Freestyle side view


As the arm is pushed forward into the water at the beginning of the freestyle stroke, there is a need to rotate the arm to move backwards in the water. However, a straight arm is inefficient, as it relies more on the shoulder muscles to move the arm and exerts a significant motion downwards, wasting energy and forcing the body out of the water.

The catch motion involves bending the arm at the elbow, creating a flipper that can be used to push the water backwards. Begin by bending at the wrist and follow this with the elbow until you have a string lower arm. The key is to move from the elbow not the shoulder as this allows you to engage the more powerful latissimus muscles in the pull phase and is the reason you hear people talking about a “high elbow” technique.


Once the catch is completed the latissimus muscles pull the arm straight down along the body which ensures that most of the propulsive power is directed back and not down. This is a bit like pulling your self up in on to a ledge in front of you. By engaging the latissimus muscles you’re keeping the body streamlined and engaging bigger and stronger muscles of the back which reduces the pressure on the shoulder joint as well.

If you are struggling with this, imagine there is a ladder in the pool below you and you are pulling yourself along.


At the end of the stroke, the hand should be pointing backwards and is recovered out of the water, aided by the rocking of the upper body. This helps in moving the arm forward, as you will be moving the arm forward along the bod ( whilst still out of the water) instead of taking the arm to far back. The arm then moves forward to begin the stroke again, and by keeping the elbow high, this allows the hand to move in a more linear motion, which is faster and more efficient.


The kick is a contentious subject for swimmers. The kick provides propulsion, but is inefficient, hence the general consensus is that makes more sense to save the legs for the run and swim where they are much more valuable.

However, the kick provides a secondary role in that, especially for men, the kick stops the legs from dropping which slows the athlete down. A light flipper kick can keep the legs and body level in the water which reduces the drag and leads to a faster and more efficient swim. It’s also worth engaging a fast kick for the last 50m of the swim to wake your legs up and get the blood moving again.

The importance of freestyle breathing in triathlon

Swimming is aerobic as far as triathlon is concerned and the proper freestyle breathing technique is key to effective, efficient and panic free swimming.

In simple terms, breathing has two parts. It sucks air into the body where oxygen is extracted by the body where it helps to burn fuel and is converted into carbon dioxide in the process. After that the body expels the waste gas into the atmosphere, emptying the lungs ready for the next phase.

Aerobic performance is heavily affected by the efficiency and capacity that the body has to utilise this oxygen, and much of the training load will be focussed on increasing the bodies ability to increase how the body uses oxygen to convert fuel.

Unlike running and cycling, the act of being face down in the water adds a considerable and important complication to the act and timing of freestyle breathing, which means proper breathing technique is essential for proper performance.


We have all experienced the fear and discomfort that sets in when we can’t breath and being underwater is likely to exacerbate that feeling, especially when the body is screaming out for more oxygen to refuel tired muscles. As this feeling increases, there is a real chance of panic setting in and it is this sense of fear that either scares people off the swim or makes them give up halfway through as their body screams for more oxygen.

Being in open water, especially in a choppy sea with waves coming in from one side will add to this sense of fear and trepidation and there is a tendency to swim with your head out of the water, which will increase the drag on the body, increasing energy usage and slowing you down.


Even if you aren’t reaching panic stations, there is a tendency to allow your breathing to dictate your rhythm, such that one arm is used less efficiently than the other, reducing your power output and potentially risking serious overuse injury to your neck and shoulder.

How to avoid this

Knowledge is a powerful thing, and understanding what causes panic is key to reducing its effects and training more effective breathing techniques. Firstly, the panic feeling is caused by a feeling of pressure in your lungs which tells your body that you need to breath, and the longer this goes on, the higher the intensity of the feeling.

However, and this is really important. This is not your body telling you that you need more oxygen, it is your body telling you that it is full of carbon dioxide. It’s not your body saying breath IN, it’s your body telling you it needs to breathe OUT!

Why is this important? Simple, the key step is to realise that your body’s ability to take on oxygen is heavily affected by how empty your lungs are before you breathe in, and, as we tend to hold our breaths instinctively underwater, we are just making this more difficult for ourselves as we try and breath in and out in that fraction of a second that our mouths stick out of the water on each stroke.

By training yourself to breath out consistently when the head is underwater, we can overcome the panic caused by hold our breath and ensure that our lungs have the maximum capacity to suck in air.

In terms of timing, you will feel more comfortable that the in breath can be short and sharp, and therefore focus on the timing of your stroke dictating when you breathe, keeping your head underwater longer, and reducing the tendency for one arm to drop when taking a breath.

Bilateral freestyle breathing.

Most swimmers have a preference for breathing on one side and build a rhythm or one breath per stroke. In open water and endurance, this isn’t efficient. You spend more time with your head out of the water and run the risk of not being able to breathe comfortably if waves are coming in from your favoured side.

Triathletes tend to favour bilateral breathing which calls for alternate breathing ( left one the first stroke, right on the half stroke after), which alters your timing, but lets you spend more time underwater. In any event, you should spend some of your training breathing on the other side, as this will stop you putting too much work through one side, let you avoid injury and help you cope in rougher water.

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