Top Tips,  Training and Technique

How to prepare for an open water swim when you can only access a pool

What do you do if this is your only swimming option?

In an ideal world, if you are planning an open water swimming event or challenge, you would ensure you practise in conditions as similar as possible to those you will face on the day. But sometimes this is impractical. Maybe you live too far from a safe place to swim outdoors or your challenge is very early in the year and the water is too cold through the winter for any meaningful training.

If you’re in this situation, how do you best prepare?

Firstly, don’t despair. Elite open water swimmers do most of their training in pools, so there’s no reason you can’t. In fact, from a training perspective, the pool has several advantages. It’s easy to measure exactly how far you’ve swum and, if you use a watch, how fast you swim. This allows you to follow a structured training programme to build your swimming fitness, and this should be your first task. Find a swimming training programme (or write your own) and follow it. (See Outdoor Swimmer Issue 2, May 2017 for some examples). Occasionally, try to swim continuously for a comparable distance to your challenge to get used to not having a break.

Next, think about what additional skills or techniques you will need in open water. The key one is sighting: the act of lifting your eyes slightly above the water to see where you are going while causing minimal disruption to your stroke. You can easily practise this in a pool, and you should. Frequent sighting puts additional strain on your neck and back so it’s good to get used to it. It’s also important that you can swim straight without a line of tiles to follow. Try to ensure, in your training, that your stroke is symmetrical. Experiment by swimming with your eyes closed for a few strokes and see how quickly you veer off course (make sure no one is coming the other way first!).

If you swim with a friend you can practise drafting in the pool but unless you want to be very competitive, this isn’t essential. It would also be useful, but again not essential, to practise swimming in a tight pack as this can happen in mass participation events. It’s less traumatic if you’ve done it before and know what to expect.

Another good idea is to add some strength and conditioning training to your routine. Developing a strong core will be an asset as you get tired on a long swim and will also help with sighting and maintaining a good body position in the water. Planks are your friend. Do them every day.


Planks are your friend. Do them every day.

However, some things are harder to prepare for. If your swim will be in water that’s considerably colder than your pool, this will be a shock. Taking cold showers may help a little, but your best approach if you really don’t have access to open water is knowledge and visualisation.

Cold water has two main impacts. The first, cold water shock, happens immediately you enter the water, results in an elevated heart rate and hyperventilation, and lasts about one to two minutes. Acclimatisation reduces the impact of cold water shock, but just knowing what it is and understanding that it’s temporary will help ensure you don’t panic. If you stay within your depth with your head above the water, you will be fine. Just concentrate on breathing out and staying calm. You can practise this mentally through visualisation. Imagine yourself entering the water, the cold creeping up your legs and over your belly, your skin tingling. Picture yourself standing in the water letting out slow, controlled breaths and relaxing. Once the two minutes are over, you’ll be in the same position as anyone who has acclimatised.

The second impact of cold water is the gradual loss of body temperature which results in reduced muscle efficiency and eventually hypothermia. Recent research suggests that the only two factors affecting the rate that you lose heat are the water temperature and your body shape. Large, rounded people stay warmer longer than small skinny ones. The conclusion from this is that you don’t need to worry too much about whether you’ve acclimatised as it makes no difference to how quickly you cool down. The advantage of acclimatisation is mostly in the mind; you just don’t feel as cold as someone who isn’t used to it. Hopefully knowing this gives you the confidence to cope with the temperature. Try to enjoy the cool sensation of water on your skin while you are still warm inside.

Hypothermia is still a risk and acclimatised swimmers will know their bodies better and how long they can swim at particular temperatures. However, the evidence is that non-acclimatised swimmers are better judges of when they are getting too cold. If you start to shiver, get out.

Depending on where you swim, outdoor swimming will throw up a few other things for you to contend with. For example, some people are initially freaked out by squelchy mud or plants in the water. Swimming into weeds will make you jump if you’re not used to it and not expecting it, but they are mostly harmless. Visualise staying calm and swimming on, gently pushing the offending plants aside. Poor visibility and the inability to see the bottom also disturb some people. It is a fact that sometimes you can see nothing under the water. You could practise this in training by keeping your eyes closed when your head is underwater and just opening them when you sight. Again, use your imagination. If you’re mentally prepared for it, you will find it much less daunting in reality.

If you’re going to be wearing a wetsuit for your open water challenge, do your best to swim in it in advance. You may have to ask your local pool for permission. A wetsuit changes your position in the water and mostly makes swimming easier and faster but it will feel odd the first few times. The fewer new things you have to contend with on event day, the better. If you truly can’t wear your wetsuit in advance then allow yourself plenty of time to put it on before your swim, get help to ensure it’s properly fitted and make sure you put some wetsuit lubricant around your neck. The suit may feel constricting around the chest but don’t panic. This is normal and will ease as you get in to the swim. Start swimming more slowly than usual so that you don’t get out of breath. Remember that it’s almost impossible to sink in a wetsuit. You can always roll over and float on your back if you need a rest.

We would always recommend you get some outdoor swimming experience before taking on a race or challenge but please don’t let it stop you if you can’t. If you can swim in a pool you can swim outdoors. Tune in mentally to the new experience and it will almost certainly be a good one.

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Outdoor Swimmer is the magazine for outdoor swimmers by outdoor swimmers. We write about fabulous wild swimming locations, amazing swim challenges, swim training advice and swimming gear reviews.