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Review: Orca Aesir Thermal Swimrun Wetsuit

Written by Fiona

March 29 2023

I have been testing the women’s Orca Swimrun Aesir Thermal Wetsuit. The Aesir is a newer version of the Swimrun RS1 and has the most thermal insulation of Orca’s Swimrun range of wetsuits.

Features of Orca Aesir Thermal Swimrun Wetsuit

Thermal insulation: A combination of 4mm-thick Yamamoto neoprene and a “Light Thermal” inner lining.

High elasticity: Orca claim that while being somewhat less elastic than wetsuits in Orca’s Flex range due to its high level of thermal insulation, the materials in the wetsuit still offer “maximum performance”.

Durability: The DuraSkin 2 outer fabric in the lower torso protects the suit from abrasions caused by accessories or obstacles.

Inner pocket.

Storage: A 15cm x 12cm internal back pocket is incorporated that allows you to store basic safety equipment.

The wetsuit comes with a waterproof mesh backpack so you can carry your wetsuit and swimming gear.

  • Price: £399.
  • Buy from: Orca

My thoughts: Orca Aesir Thermal Swimrun Wetsuit

It is important to check the sizes to ensure a good fit. The fit will provide good thermal insulation while also allowing you to swim with ease. The is a sizing guide that worked well for me.

It is also a good idea to know which way round to wear the wetsuit! My first try was back to front and while it still worked well in terms of warmth and flexibility, I found the neck to be annoying! Once I realised that the zip goes at the front, this issue was resolved.

I normally swim year-round in a swimming costume with an Orca neoprene vest. Find out more about the kit and others things I’ve learned about wild swimming. I also wear neoprene gloves and socks.

However, there was one area that ended up very cold in all months apart from the height of summer – and that is my nether regions!

I could wear a full wetsuit for maximum warmth and protection from cold water but I like the feeling of the cold water on my arms and legs. I find the feeling of the cold or freezing water to be therapeutic. I like open water swimming for the mental health side of the activity, rather than only for physical fitness. I would say I am more of a swim “dipper” and short-distance swimmer.

I am also becoming interested in swim-run or swim-hike adventures but with the focus on the hiking and running, while making short swim crossings of lochs and in the sea.

So, it made sense for a number of reasons to try a swim-run wetsuit. These types of wetsuits could also be called “shortie” wetsuits, in that they have short legs and arms. Getting in and out of a shortie wetsuit is a lot easier than when wearing a full length wetsuit, so that is another advantage.

Anyway, let me tell you what it was like to spend time in the Orca Aesir Thermal Swimrun Wetsuit in cold water.

The places I like to swim.

Swimming in Orca Aesir Thermal Swimrun Wetsuit

I often take a short swim or dip in my local loch. The water is still very cold but I am used to spending a short spell in cold water because I have been doing so for about two years and in all seasons.

If I was wearing a neoprene vest, gloves and socks with my ordinary swimsuit, I would expect to be in the water for a few minutes at most. I don’t really like to talk or write about the duration of my swims because it’s not a competition and it doesn’t matter how long we each stay in the water. These things are very individual and will depend on desires, body fat and experience.

However, I wanted to compare the swimrun wetsuit to my usual swim gear. I was able to stay in the water for almost four times the duration. I felt much warmer across my torso and nether regions, too!

As the water temperature has risen in the past week, I have still been using the Orca swim-run suit. It means I can stay in for much longer than I usually do and enjoy even greater benefits of being in the water.

I was still able to enjoy the cold water sensation on my bare arms and legs, but I felt much less impact of the cold water on the rest of my body.

The wetsuit also gave me more buoyancy than the neoprene vest alone. I felt this as soon as I got in the water and launched myself horizontally. I felt like my body was floating nicely in the water without much effort at all.

The wetsuit is also nicely flexible at the shoulders so I could easily swim. There was no restriction at all (once I worked out I needed to wear the wetsuit the right way round!)

I have not taken the wetsuit for a run yet but I can see it will be easy enough to unzip it if I end up feeling too warm while running. It does seem like a bit of an odd activity to run in neoprene, which has a high potential to make you sweat, but the weather in Scotland is often cool. I’ll be reporting back on the running.

I wanted a wetsuit that would give good warmth in Scottish lochs and the sea but also offer the advantages I fonud from having some bare skin in the cold water. The fact, I will be able to use the Orca Aesir Thermal Swimrun Wetsuit for potential swim-run and swim-hike adventures is a bonus.

There is another consideration when reviewing this wetsuit and that is the cost at £399. I was sent the wetsuit to try and in return for an honest review but this price is a big outlay for many people.

If you plan to swim longer distances in cold water and you are keen on swim-run events, it is a wetsuit I’d recommend for warmth and performance in cold water. If you are only planning on a bit of a swim around or a swim dip, I think I’d search for a cheaper product.

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