Outdoor swimmers, swim smart in the heat

As outdoor swimmers, particularly those of us that live in a northern European country, our biggest concern is often how to keep warm. We’re not often faced with the prospect of overheating, but it is something to bear in mind during a heatwave. Here’s how to swim smart, enjoy the water and stay safe when it’s hot.

A group of swimmers entering a lake

The water temperature in inland lakes in southern Britain has, in some cases, exceeded 26 degrees this week (mid-July 2022). These temperatures are usually reserved for tropical seas or indoor heated pools. If you choose to wear a wetsuit at these temperatures, you should be aware of the risks of overheating, which range from mild discomfort to dehydration, hyperthermia (rather than hypothermia) and, in extreme cases, death.

Our recommendations for swimming in the heat are as follows:

  • Swim without a wetsuit or try a shortie wetsuit.
  • Try to avoid swimming during the hottest part of the day (especially if you are still wearing a wetsuit).
  • Stay hydrated before, during and after your swim.
  • Reduce your effort level and/or time in the water, again, especially if you are still wearing a wetsuit.
  • If you are wearing a wetsuit, tug it gently at the neck occasionally to let in fresh cooler water.
  • Use a thin latex swimming hat rather than a thicker silicon one.

Interestingly, even at the temperatures we are experiencing, some swimmers are still reluctant to swim without a wetsuit. We thought we’d take a brief look at some of reasons for this and offer solutions.

I’m not used to it and I’m worried I’ll panic

Wetsuits help you float so it’s understandable to worry about being less buoyant without one. However, if you can swim in a pool without one, you should be able to swim in open water without one too. Start with short swims and stay close to the shore and/or within your depth initially. Use a tow float or Restube so that you have something to rest on if you get tired or anxious. If you’re swimming at a supervised venue, let the safety team know you’re nervous and ask them to keep an eye on you.

I’m too slow without a wetsuit

Too slow for what? If you’re not in a race, does it matter? Sure, it won’t look so good on Strava, but you need to balance that with the very real risks of overheating. If you’re training, it’s your effort level that’s relevant, not your actual speed.

My legs sink

There’s a short-term solution to this and a (better) long-term one. You can use buoyancy shorts, neoprene leggings or a pull-buoy to keep your legs nearer the surface as an immediate fix. Longer-term, seek the advice of a coach to look at your swimming technique. Most cases of sinking legs are not caused by bulky leg muscles or heavy bones but by poor stroke mechanics.

I’ll get sunburnt

Try swimming early or late in the day or use a thin rash vest instead. Use sunblock (eco-friendly preferred).

I’m training for a wetsuit-compulsory event

It’s much easier to switch from non-wetsuit in training to wetsuit in an event than the other way around. You will still get the same training benefit swimming without your wetsuit. You may even get a better workout as you will need to work harder to maintain a good body position. The better you get at swimming without a wetsuit, the faster you will be when you put it back on for your event. If you’re still worried about it, swim 10 to 15 minutes at the beginning of your session with the wetsuit and then remove it.

I’m not comfortable with how I look in a swimming costume

Unfortunately, lots of people feel like this. The good news is that the outdoor swimming community is very welcoming and non-judgemental. If you’re still anxious, wrap a towel around yourself to walk to the water, and leave it somewhere easy to grab as soon as you leave the water again. Once you’re in the water, only your head is exposed anyway. Swim with a supportive friend.

I prefer to keep my body covered for religious or other personal reasons

A number of swimming businesses now offer full-body swimming costumes. For example see: www.speedo.com/women-s-hijab-black/13512319.html

These will keep you cooler than a wetsuit.

My coach has asked me to do a timed swim in race conditions

Most races will ban wetsuits at these temperatures, so it’s good to practice without. It’s also useful to know how much benefit you get from wearing a wetsuit by timing yourself without.

For most people, removing their wetsuit for the first time feels liberating, and they enjoy the experience of natural water against their skin. People report it makes them feel closer to the elements or that it gives them a new sense of freedom. It’s also a lot less faff – no need to clean and dry a wetsuit afterwards or mess around with wetsuit lubricant before.

However, non-wetsuit swimming is not for everyone, at any temperature. If you are very susceptible to the cold or are perhaps recovering from illness and need the additional support of the wetsuit, do not feel compelled to swim without – but be aware of the risks of heat as well as cold.

Thanks to Katia Vastiau at Queenford Lake for providing images for this article and suggestions to improve it.

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I created Outdoor Swimmer in 2011 (initially as H2Open Magazine) as an outlet for my passion for swimming outdoors. I've been a swimmer and outdoor swimmer for as long as I remember. Swimming has made a huge difference to my life and I want to share its joys and benefits with as many people as possible. I am also the author of Swim Wild & Free: A Practical Guide to Swimming Outdoors 365 a Year and I provide one-to-one support to swimmers through Swim Mentoring.