Open Water Swimming in the Sea


Here in the UK, we live on an island and so as you go through your triathlon or swimming career journey, you will inevitably start swimming in the sea at some point.

Along with the sea come waves, tides, currents, jellyfish, weaver fish, rocks, seasickness, boats and salty water. These are all hazards to contend with that you will not have come across swimming in inland lakes.

Swimming in the sea is unlike other forms of open water swimming, but you will reconnect with the child that you once were as you dive through the waves. So don’t worry about the hazards, read on as we help get you out there and you will find – actually - that you love it!


Don’t underestimate the power of the sea

Before you swim, spend some time watching the sea and the way that it behaves. You can go online to find out the tide times, which is useful to understand. Find out whether there are spring tides running and at what time the tides will turn.

Ask the lifeguards for advice, such as where to swim and if there are any rip tides to avoid from outgoing estuaries, for instance. Tell them what you plan to do and importantly when you come back from your swim, tell them that you are out again. It is basic good manners, but it also may save your life should you run into difficulties.



Wear the right kit for open water swimming in the sea

When you go out, it is important to dress for the sea. This means a bright top swimming hat, and if it is cold, wear this over a neoprene cap. This is to give others good visibility of the main thing that will be in sight over the open water – your head!

You will need goggles for the conditions and socks to protect you from rocks, glass on the beach, weaver fish under the sand and other sharp objects that you won’t be able to see in the dark of the water.

Remember to take off any rings as your fingers will shrink in the cold water and they may slip off. You also need to remember to leave your kit well up the beach above the tide line as it is almost guaranteed that the tide will come in while you are out at sea!


Beach starts and deep water starts

An open water sea race may have a beach start or a deep water start. Both are very different beasts and so you will need to practice how to deal with both, where deep water starts will come a little more easily to you.

Practice the trickier of the two, the beach starts. Enter the water by running in, diving through the waves or knee high running through the shallows. Running in water is not easy and so you need to stage the way you get into the water, and as you get deeper try a couple of dolphin dives and then start swimming properly. Only time and experience will get you to arrive at a technique that works best for you but you don’t want to find yourself surprised by beach starting for the first time on the start line of a race.



Getting used to swimming in the sea

To get used to the power of the sea, swim out a short distance and then just float in the water over a rock. As you float, observe how you move with the current or tide.

When swimming in the sea you need to swim the distance, but you also need to swim against or with the current. You will need to work at correcting your course if the pull is in the water is strong.

Sea swimming really drives home the need to breathe on either side. If you can only breathe one side you will be facing the rolling waves, or a low sun that blinds you. Breathing one side may also have you with your back to the beach and have you not having any idea where you are if you are trying to swim parallel.

Sighting over waves is going to be harder than in the relative calm of a lake swim, so you will need to catch sight when you can. You will probably need to lift your head higher than normal and concentrate on not letting your feet drop.

The traditional high elbow stroke may need adjusting to a more straight arm swing over. This will stop your hand snagging on a wave. Practice this in a pool and then put this into action in the waves.

If all this makes you feel seasick, you are not the only one. A seasickness remedy can help; drowsiness from the tablets is unlikely to be a problem under the circumstances!


Doing the distance for the first time

To get started, swim out to sea and if there is something to aim for then head towards it. If there is nothing, then try swimming out approximately 150 strokes, then turn around and aim back to your start point.

Whilst you are doing this you will be able to observe the feeling of currents, the swell of the waves and the difference in the speed of your swim on the way out versus the way back in depending on which way the tide is running.

Next, swim out again and turn left or right and swim parallel to the beach for 100 strokes or so before swimming back to the start forming a triangle from your start point.

Third time in the water, swim out then parallel and then straight back to shore in a box shape. You should now have a feeling for the piece of sea you have been swimming in and how you cope with the movement of the water. You will also realise how much further away the beach appears to be when you swim back to it!


Coming out of the water well

Coming back to shore needs practice if you are racing in particular. You need to time when you need to stop swimming and start running. Most beginners stop swimming too soon. It is really, really hard to run in water that is higher than your knees so try dolphin diving the last few metres or even body surfing to get you to shallow water. It all depends on the beach, but practice all the options to get your technique perfected.


Beach training tips

Have half an hour on the beach? Do some sets of beach starts, hard out, turn, hard in, sprint out and run on the beach for 30 seconds. Recover then repeat. You won’t be able to manage many to begin with but it’s great training for getting you used to the start and exit to T1.


Finish your housekeeping when you exit the water

When you come out tell someone that you have finished in the sea. Don’t be the cause of a lifeboat launch, and especially don’t swim to another beach and leave the lifeguards looking for you.

Lastly, thoroughly rinse your wetsuit and goggles in fresh water, don’t just dump them back in your bag. Salt and rocks are not good for your best racing wetsuit,so if you plan on making a habit of this, get yourself a training wetsuit and save your best for best.

Very lastly, always swim with someone slower than yourself, for the sharks.


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